Cluster headache suicidality: a systematic review with a meta-analysis

Cluster headache suicidality: a systematic review with a meta-analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Cluster headache suicidality: a systematic review with a meta-analysis Elise K Van Obberghen, Roxane Fabre, Michel Lanteri-Minet This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7221366/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Dec, 2025 Read the published version in The Journal of Headache and Pain → Version 1 posted 10 You are reading this latest preprint version Abstract Background: Suicide is considered as common in patients with cluster headache (CH) and is defined as ‘suicidal headache’. However, the exact level of suicidality is not known and is intuitively assumed to be correlated with the CH severity. Methods: This work is a systematic review of data accessible through PubMed and published up to July 25, focusing on the suicidality of CH according to the rates of suicidal ideation and suicide attempts. This meta-analysis was carried out with all selected studies then by considering studies with specialized recruitment and studies with non-specialized recruitment. A qualitative analysis was performed to identify determinants of CH suicidality. Results: Among the 53 publications identified, 12 were selected corresponding to 10 studies. These selected studies included a total of 34180 subjects (range 75-24131). Eight were performed in a specialized field (headache tertiary center, neurology clinic or via CH patients’ association) and 2 in a non-specialized field (via heath registry). The overall rate of suicidal ideation in CH was estimated at 8.0% (95%CI [7.7; 8.3] and overall rate of suicide attempts in CH was estimated at 1.2% (95%CI [1.1; 1.3]). In a non-specialized field, these rates were estimated at 5.2% (95%CI [4.9; 5.4]) and 1.1% (95%CI [1.0; 1.2]) respectively. In specialized field, these rates were estimated at 44.6% (95%CI [42.7; 46.6]) and 5.1% (95%CI [3.9; 6.7]) respectively. The qualitative analysis showed that few determinants have been considered but it appears that the risk is greater during CH attacks, and it involves psychological determinants such as demoralization. Conclusion: The overall suicidal risk in CH does not appear to be higher than that of the general population, but there is a suicidal risk increase among CH patients followed up in specialized field. This higher risk is indeed probably related to the severity of CH in terms of pain, but it is also probably related to other factors such as impulsive aggressiveness during CH attacks and psychological factors such as demoralization. Registration: The systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (number: CRD420251110095). cluster headache suicidal ideation suicide attempts burden Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Cluster headache (CH), which is the most common of the trigeminal autonomic cephalalgias (TACs), is characterized by attacks of severe to very severe unilateral (orbital, supraorbital and/or temporal) pain lasting from 15 to 180 minutes (when untreated) associated with ipsilateral autonomic symptoms and/or with restlessness or agitation [1]. Attacks occur once every other day to eight times a day with pain-free periods of at least 3 months in episodic CH (ECH) and without remission or with remissions lasting less than 3 months in chronic CH (CCH) [1]. Due to the severity and recurrence of attacks, this primary headache is referred to as a ‘suicidal headache’ [2] with tragic clinical observations such as that of a 56-year-old male with a history of CCH who, during a nocturnal attack, aimed a shotgun toward his symptomatic eye and fired [3]. It is therefore essential to estimate the rate of suicide attempts associated with the cluster headache. It is also essential to estimate the rate of suicidal ideations in this primary headache because, if most instances of suicidal ideation do not lead to suicide attempts [4], suicidal ideation is a predictor of suicide attempts [5]. Unfortunately, to date, the level of suicidality, considering the rate of suicidal ideation and the rate of suicide attempts, has not been reported in a large representative CH population [6]. It is also likely that suicidality differs according to the severity of the cluster headache, so that interpretation of the results of studies devoted to this component of the CH burden must consider the origin of the patients included in these studies (general population, healthcare claims data, primary care, CH patients’ association websites, neurology, headache tertiary care). The aim of our work was to perform a systematic review of data on suicidality associated to CH published up to July 2025. This systematic review includes a meta-analysis considering studies carried out in headache tertiary centers, neurology clinics or via CH patients’ association websites and those with a broader recruitment from the general population, primary care or via healthcare claims data. This systematic review also includes a comparison of the rates of passive and active suicidal ideation and an identification of determinants of suicidality in CH patients. Methods This systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines [7]. In accordance with these guidelines, our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (registration number: CRD420251110095). Search strategy A comprehensive search on PubMed database was carried out in July 2025. The search terms were ‘suicidality’ OR ‘suicide’ OR ‘suicidal ideation’ OR ‘suicidal tendencies’ OR ‘suicidal thoughts’ OR ‘suicidal plan’ OR ‘suicidal attempt’ OR ‘self-injury’ These were combined with a search for ‘cluster headache’. In addition to this electronic search, we screened the reference lists of the selected articles and relevant literature known by the authors. Inclusion criteria were: i) prospective and retrospective studies, case series and survey on suicidality and CH; ii) adult or children subjects with a diagnosis of cluster headache done by a physician or according to International Classification of Headache Disorders (ICHD) criteria or according to the International Classification of Diseases (ICD) ; iii) no restrictions by date; iv) no restrictions by geographical location; v) English language articles. Exclusion criteria were: i) case reports; ii) adult or children subjects with a CH self-diagnosis; iii) studies with less than 10 participants. According to these inclusion/exclusion criteria, two authors (VOE and LMM) independently assessed all title and abstracts for inclusion. Full-text papers were retrieved for articles meeting the eligible criteria and for articles for which these criteria could not be verified solely by the title and abstract. All full-text articles were assessed independently by two authors (VOE and LMM), and disagreement was resolved by discussion to reach consensus. Data extraction Data were independently extracted by two authors (VOE and LMM). Data extracted included date, country, study design, recruitment (general population, primary care, healthcare claims data, CH patients’ association website, neurology clinic, headache tertiary center), methods of data acquisition, population (number of participants, age, men: women ratio, percentage of participants with ECH and CCH), method of CH diagnosis, method to suicidality evaluation, rate of suicidal ideations (passive and active), suicidal plan and suicide attempts. The discrepancies were resolved by discussion to reach consensus amongst VOE and LMM. Risk of bias (quality) assessment Quality assessment of studies selected in this systematic review was performed using the Joanna Briggs Institute (JBI) Appraisal Checklist tool [7] for case series studies and the Oxford Centre for Evidence-Based Medicine (OCEBM) critical appraisal tool [8] for survey studies. The studies were independently assessed by two authors (VEO and LMM) and the discrepancies were resolved by discussion to reach consensus. Analysis This work involved two analyses, one quantitative and one qualitative Quantitative analysis The quantitative analysis was based on a meta-analysis. For this meta-analysis, we used the rate of suicidal ideation, considering passive suicidal ideation, and the rate of suicide attempts as indicators of suicidality in patients suffering from CH. The rates of suicidal ideation and suicide attempts with the respective 95% confidence interval (CI) were calculated on the combined numbers in the selected studies. Study heterogeneity was performed using I2 (less than 25% viewed as low heterogeneity, between 25% and 50% as moderate, and over 50% as high heterogeneity). We conducted a meta-analysis of all the selected studies, as well as two other meta-analyses, one including studies from specialized recruitment (CH patients’ association website, neurology clinic, headache tertiary center) and the other including studies from non-specialized recruitment (general population, primary care, health registry). The metaprop function in the meta package of R-4.3.0 software was used. Qualitative analysis For the studies in which data were available, the quantitative analysis compared the rates of passive and active suicidal ideation. Similarly, for the studies in which data were available, the quantitative analysis sought to identify possible determinants of suicidality in CH patients. Results Studies selected The search carried out on data related to suicidality and CH published up to July 2025 is summarized in the PRISMA flow chart presented in Figure 1. This search identified 53 unique articles published between February 1952 and April 2025. All articles were screened by title and abstract and 27 articles were excluded at this stage. Full-text articles were assessed for the remaining 25 articles and finally 12 articles, published between April 2011 and April 2025, were selected for the systematic review (Table 1). Among the selected articles, 3 were from the same study [11,12, 14] and 9 from other studies [10, 13, 15, 16, 17, 18, 19, 20, 21]. Studies were survey studies [11, 12, 13, 14, 16, 19, 20, 21], case series studies [10, 15, 18] and a clinical trial [17]. Two were international studies [17, 20] and the other studies were national studies of which 4 took place in USA [11, 12, 13, 14, 16, 19], 2 in Europe [10, 21] and 2 in Asia [15, 18]. Five of the study cohorts were recruited from tertiary headache centers and neurology clinics [10, 15, 17, 18, 21], 3 were recruited through CH patients’ association websites [11, 12, 14, 16, 20] and 2 were recruited through healthcare claims data [13, 19]. These selected studies included a total of 34180 subjects (range 75-24131). This whole population was composed of 27703 men, 6195 women and 282 subjects with sex not specified. The form of CH was indicated only 1028 subjects with 586, 331 and 111 corresponding to ECH, CCH and undetermined respectively. Data extracted Data extracted in the 12 selected articles related to the 10 considered studies are presented in Table 2. All the studies were considered for the quantitative analysis and among them all reported the rate of suicidal ideations [10-21] whereas only 7 studies reported the rate of suicide attempts [11-19]. The rates of passive and active suicidal ideation were specified in two studies [15, 16] and were considered for the qualitative analysis. Six studies presented data related to determinants of suicidality in cluster headache [10, 11, 12, 14, 15, 16, 18, 19] and were considered for the qualitative analysis. Risk of bias of individual studies Assessment of selected case series [10, 15, 18] using Joanna JBI Appraisal Checklist tool is summarized in Table 3 and assessment of selected surveys [11, 12, 13, 14, 16, 19, 20, 21] using OCEBM critical appraisal tool is summarized in Table 4. The clinical trial [17] was evaluated individually. Selected studies were not excluded based on their quality appraisal. Overall rates of suicidal ideation and suicide attempts in CH Considering the ten studies (34180 subjects) for which the rate of suicidal ideation was reported, and which were included in the meta-analysis [10-21], I 2 was estimated at 99.7%. A Forest-plot of the overall rate of suicidal ideation in CH is presented in Figure 2. The overall rate of suicidal ideation in CH was estimated at 8.0% (95%CI [7.7; 8.3]). Considering the seven studies (33807 subjects) included in the meta-analysis [11-19], for which the rate of suicide attempts was reported, the I 2 was estimated to be 93.8%. Forest-plot of the overall rate of suicide attempts in CH is presented in Figure 2. The overall rate of suicide attempts in CH was estimated at 1.2% (95%CI [1.1; 1.3]). Rates of suicidal ideation and suicide attempts in CH according to studies recruitment Specialized recruitment Considering the 8 studies in which the rate of suicidal ideation was reported, with a specialized recruitment (2460 subjects), and included in the meta-analysis [10-12, 14-18, 20-21], I 2 was estimated to be 97.2%. A Forest-plot of the rate of suicidal ideation in CH reported in specialized fields is presented in Figure 3A. The rate of suicidal ideation in CH reported in specialized field was estimated at 44.6% (95%CI [42.7; 46.6]). Considering the 5 studies with specialized recruitment (2087 subjects) for which the rate of suicide attempts was reported and included in the meta-analysis [11-12, 14-18], I 2 was estimated to be 77.5%. Forest-plot of the rate of suicide attempts in CH reported in specialized field is presented in Figure 3B. The rate of suicide attempts in CH reported in specialized field was estimated at 5.1% (95%CI [3.9; 6.7]). Non-specialized recruitment Considering the 2 studies with a non-specialized recruitment (31720 subjects) for which the rate of suicidal ideation was reported, and which were included in the meta-analysis [13, 19], I 2 was estimated to 99.6%. Forest-plot of the rate of suicidal ideation in CH reported in non-specialized field is presented in Figure 4A. The rate of suicidal ideation in CH reported in non-specialized field was estimated at 5.2% (95%CI [4.9; 5.4]). Considering the 2 studies with a non-specialized recruitment (31720 subjects) for which the rate of suicide attempts was reported, and which were included in the meta-analysis [13, 19], I 2 was estimated to 98.2%. Forest-plot of the rate of suicide attempts in CH reported in non-specialized field is presented in Figure 4B. The rate of suicide attempts in CH reported in non-specialized field was estimated at 1.1% (95%CI [1.0; 1.2]). Comparison of rates of passive suicidal ideation and active suicidal ideation Ji Lee et al showed that the rate of active suicidal ideation was lower than the rate of passive suicidal ideation (35.8% vs. 64.8%) in the ictal phase, whereas its rates were similar in the inter-ictal phase (3.8% vs. 4%) [15]. Regardless of ictal and interictal assessment, Koo et al also found a lower rate of active suicidal ideation than passive suicidal ideation (25% vs 47%) [16] Determinants of suicidality in CH The influence of gender on suicidality in CH has been evaluated in two studies [12, 19} with contradictory results. Rozen and Fischman found no statistically significant difference in the rates of suicidal ideation and attempted suicide between men and women [12], whereas Seng et al found significantly higher rates of both in men [19]. The influence of the CH form was evaluated in two studies [10, 16]. Jürgens et al suggested a higher rate of suicidal ideation in patients suffering from CCH but did not assess its significance [10]. Koo et al found no difference in the rate of suicide attempts according to the form of CH [16]. Kim et al found a significant association between the rate of suicidal ideation and the delay in diagnosis (≥ 7 years) but did not find such an association for the rate of suicide attempts [18]. In a detailed study of patients suffering mainly (almost 90%) from ECH, Ji Lee et al showed that the clinical expressivity of CH influenced the rates of suicidal ideation and suicide attempts, which were higher during attacks than between attacks or during periods of remission [15]. In this work, the authors carried out a study of factors associated with suicidality [15] showing that ictal suicidality was associated with the CH duration, the HIT-6 score and the PHQ-9 score, whereas interictal suicidality was associated with the cumulative number of painful bouts and the PHQ-9 score (detailed data in Table 2). In another association study, Koo et al [16] showed that the rate of suicidal ideation was linked to demoralization (according to demoralization diagnostic criteria for use in psychosomatic research and the Kissane Demoralization Scale) and not to depression (detailed data in table 2). Finally, Rozen showed an association between the rate of suicidal ideation of CH patients and smoking [14]. Discussion Suicide is considered as common in patients with CH, to the point that CH has been defined as ‘suicidal headache’. However, the exact level of suicidality is not known and is intuitively assumed to be correlated with the severity of CH. Our main objective was to specify the suicidality associated with CH and to evaluate whether it differed according to whether it was evaluated in a specialized field (with a selection bias in favor of the most severely affected patients) or in a non-specialized field (with a lesser selection bias due to the inclusion of patients of varying severity and being more representative of patients suffering from CH as a whole). To do this, we carried out a systematic review to studies that evaluated the suicidality of CH. We then performed a meta-analysis in three stages: i) for all the studies, ii) for studies carried out in a specialized field (studies with recruitment in a tertiary headache center, a neurological clinic or via the website of a CH patients’ association) and iii) for studies carried out in a non-specialized field (studies using medical records of heath registry). This meta-analysis assessed at the two extremes of suicidal behavior, i.e. suicidal ideation and suicide attempts. The overall rate of suicidal ideation in CH was estimated at 8% (95%CI [7.7; 8.3] and the overall rate of suicide attempts in CH was estimated at 1.2% (95%CI [1.1; 1.3]). Meta-analysis performed with studies related to a recruitment in a non-specialized field (which concerned more than 90% of patients included in all selected studies) shows similar results with rate of suicidal ideation and rate of suicide attempts estimated at 5.2% (95%CI [4.9; 5.4]) and 1.1% (95%CI [1.0; 1.2]) respectively. These figures do not seem to indicate a higher overall level of suicidality associated with CH when compared with available epidemiological data on suicidality in the general population. For example, in an analysis of World Mental Health Survey data from 17 countries, the reported cross-national lifetime prevalence (standard error) of suicidal ideation and the reported cross-national lifetime prevalence (standard error) of suicide attempts were 9.2% (0.1) and 2.7% (0.1) respectively [22]. Nevertheless, a recent Danish population-based cohort study, not included in our meta-analysis because it did not individualize patients with CH, showed a suicidal risk increase in subjects diagnosed with TAC (n=6872) compared to matched controls (n=597430) demonstrated by hazards for attempted suicide (HR, 1.97; 95% CI, 1.35-2.87) and for completed suicide (HR, 2.40; 95%CI, 1.23-4.66) [23] On the other hand, the meta-analysis carried out on the studies recruited from the specialized field revealed a much higher level of suicidality associated with CH with rate of suicidal ideation and rate of suicide attempts estimated at 44.6% (95%CI [42.7; 46.6]) and 5.1% (95%CI [3.9; 6.7]) respectively. As assumed by the background of our study, such results argue in favor of a suicidal risk which would concern the most severely affected CH patients. Surprisingly, our systematic review did not find any robust data comparing the suicidality of patients suffering from ECH with that of patients suffering from CCH. On the other hand, Ji Lee et al showed higher rates of suicidal ideation and suicide attempts during CH attacks [15]. Such ictal suicidality may be explained by the extreme severity of the pain, but it could also be part of the behavior observed during CH attacks. Beyond restlessness, which is a diagnostic criterion for CH [1], impulsive self-inflicted injuries have been reported during CH attacks [24]. Such self-aggressiveness could result from the activation of the posterior hypothalamus demonstrated during the CH attack [25]. There is basic evidence for the involvement of the ventro- and dorsomedial as well as the posterior hypothalamus in the pathophysiology of aggressiveness [26] and the posterior hypothalamus has been proposed as a target to treat patients with refractory aggressiveness using hypothalamotomy [27] or deep brain stimulation [28]. Given that the disruption of the hypothalamic–pituitary–adrenal axis plays a key biological role in stress reactivity associated with suicidal behavior [29] and that impulsivity is a component of most psychological models of suicide [30], the impulsive aggressiveness observed in CH attacks could be an important precipitating factor of suicidal behavior observed during the ictal phase of the CH [3]. Caution is also needed when interpreting the relationship between suicidal risk in CH patients and depressive comorbidity, which is three times more frequent in these patients [31]. Overall, the association seems obvious, especially as it has been well demonstrated that depression, like all other psychiatric disorders, increases the risk of suicide [32]. The results of Ji Lee et al point in this direction, showing a significant association between the PHIQ-9 score and suicidality, whether ictal or interictal [15]. However, in a more detailed study of the psychological determinants of suicidality in CH patients, Koo et al showed that the rate of suicidal ideation was linked to demoralization (according to demoralization diagnostic criteria for use in psychosomatic research and the Kissane Demoralization Scale) and not to depression [16]. Interestingly, Koo et al found that suicidal ideation was associated with depression and not to demoralization in controls [16], suggesting that demoralization may be particularly sensitive to suicidality in CH. Our qualitative analysis has shown that certain determinants of suicidal risk have not been evaluated in studies devoted to this topic. In particular, the association of suicidal risk with sleep disturbances and the use of illicit drugs was not considered, whereas both are pain-related risk factors for suicidality in chronic pain [33]. Sleep disturbances and illicit drug use should therefore be considered in association studies with suicidality, as they are more frequently observed in CH patients than in the general population [34, 35] Conclusion This systematic review showed an overall suicidal risk in CH that may not be significantly higher than in the general population. On the other hand, it showed a clear increase in this risk among CH patients followed up in specialized fields (tertiary care center patients, neurological clinic, patients linked to patients' associations), with almost half of these patients declaring suicidal ideations and more than 5% having made suicide attempts. These patients are a priori the most severely affected by CH, with the highest intensity of pain during attacks, the highest number of attacks and significant depressive comorbidity. Nevertheless, the qualitative analysis carried out in this systematic review suggests that the suicidal behavior observed in CH is more complex, probably involving impulsive aggressiveness during attacks and demoralization. Future studies aimed at clarifying the determinants of suicidal risk in CH will need to integrate all these elements, adding sleep disorders and illicit drug use, two potential determinants that have never been considered to date. Such an approach is essential if we are to develop effective suicide prevention for CH patients. Declarations Ethic approval and consent to participate This systematic review did not require the authorization of an ethics committee. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (registration number: CRD420251110095). Consent for publication Not applicable Available data and materials The datasets used and/or analysis during the current review are available from the corresponding author on reasonable request Competing interests VOE had received personal fees for consultancy activities from Abbvie FR had no conflict of interest. LMM received personal fees for consultancy activities from: Abbvie/Allergan, Amgen, Eli Lilly, IPSEN, Lundbeck, Medtronic, Novartis, Orion Pharma, Perfood, Pfizer, Reckitt-Benckiser, Savia, Bioelectronics, Teva, UPSA. . Funding This study was supported by FHU InovPain Authors’ contribution VOE and LMM conceived the study. EVO and LMM performed studies selection, data acquisition and data analysis. FR performed statistical analysis. EVO and LMM drafted the manuscript. A All authors revised and approved the final manuscript References Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018 Jan;38(1):1-211. doi: 10.1177/0333102417738202. PMID: 29368949. Horton BT. Histaminic cephalgia. J Lancet. 1952 Feb;72(2):92-8. PMID: 14908316. Rothrock J. Cluster: a potentially lethal headache disorder. Headache. 2006 Feb;46(2):327. doi: 10.1111/j.1526-4610.2006.00346.x. PMID: 16492244. Klonsky ED, Dixon-Luinenburg T, May AM. The critical distinction between suicidal ideation and suicide attempts. World Psychiatry. 2021 Oct;20(3):439-441. doi: 10.1002/wps.20909. PMID: 34505359; PMCID: PMC8429339. Franklin JC, Ribeiro JD, Fox KR, Bentley KH, Kleiman EM, Huang X, Musacchio KM, Jaroszewski AC, Chang BP, Nock MK. Risk factors for suicidal thoughts and behaviors: A meta-analysis of 50 years of research. Psychol Bull. 2017 Feb;143(2):187-232. doi: 10.1037/bul0000084. Epub 2016 Nov 14. PMID: 27841450. Kim SA, Choi SY, Youn MS, Pozo-Rosich P, Lee MJ. Epidemiology, burden and clinical spectrum of cluster headache: a global update. Cephalalgia. 2023 Sep;43(9):3331024231201577. doi: 10.1177/03331024231201577. PMID: 37728577. Shamseer L, Moher D, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P, Stewart LA; PRISMA-P Group. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015: elaboration and explanation. BMJ. 2015 Jan 2;350:g7647. doi: 10.1136/bmj.g7647. Erratum in: BMJ. 2016 Jul 21;354:i4086. doi: 10.1136/bmj.i4086. PMID: 25555855. Moola S, Munn Z, Sears K, Sfetcu R, Currie M, Lisy K, Tufanaru C, Qureshi R, Mattis P, Mu P. Conducting systematic reviews of association (etiology): The Joanna Briggs Institute's approach. Int J Evid Based Healthc. 2015 Sep;13(3):163-9. doi: 10.1097/XEB.0000000000000064. PMID: 26262566. CEBM - Centre for Evidence Based Medicine (2014) Critical AppraisalTools. https:// www. cebm. net/ 2014/ 06/ criti cal- appra isal. Accessed 20 Mar 2025. Jürgens TP, Gaul C, Lindwurm A, Dresler T, Paelecke-Habermann Y, Schmidt-Wilcke T, Lürding R, Henkel K, Leinisch E. Impairment in episodic and chronic cluster headache. Cephalalgia. 2011 Apr;31(6):671-82. doi: 10.1177/0333102410391489. Epub 2010 Dec 1. Erratum in: Cephalalgia. 2011 Apr;31(6):766. PMID: 21123629. Rozen TD, Fishman RS. Cluster headache in the United States of America: demographics, clinical characteristics, triggers, suicidality, and personal burden. Headache. 2012 Jan;52(1):99-113. doi: 10.1111/j.1526-4610.2011.02028.x. Epub 2011 Nov 11. PMID: 22077141. Rozen TD, Fishman RS. Female cluster headache in the United States of America: what are the gender differences? Results from the United States Cluster Headache Survey. J Neurol Sci. 2012 Jun 15;317(1-2):17-28. doi: 10.1016/j.jns.2012.03.006. Epub 2012 Apr 5. PMID: 22482825. Choong CK, Ford JH, Nyhuis AW, Joshi SG, Robinson RL, Aurora SK, Martinez JM. Clinical Characteristics and Treatment Patterns Among Patients Diagnosed With Cluster Headache in U.S. Healthcare Claims Data. Headache. 2017 Oct;57(9):1359-1374. doi: 10.1111/head.13127. Epub 2017 Jun 5. PMID: 28581025; PMCID: PMC5655925. Rozen TD. Cluster Headache Clinical Phenotypes: Tobacco Nonexposed (Never Smoker and No Parental Secondary Smoke Exposure as a Child) versus Tobacco-Exposed: Results from the United States Cluster Headache Survey. Headache. 2018 May;58(5):688-699. doi: 10.1111/head.13295. Epub 2018 Mar 14. PMID: 29536529. Ji Lee M, Cho SJ, Wook Park J, Kyung Chu M, Moon HS, Chung PW, Myun Chung J, Sohn JH, Kim BK, Kim BS, Kim SK, Song TJ, Choi YJ, Park KY, Oh K, Ahn JY, Lee KS, Cho S, Chung CS. Increased suicidality in patients with cluster headache. Cephalalgia. 2019 Sep;39(10):1249-1256. doi: 10.1177/0333102419845660. Epub 2019 Apr 24. PMID: 31018651. Koo BB, Bayoumi A, Albanna A, Abusuliman M, Burrone L, Sico JJ, Schindler EAD. Demoralization predicts suicidality in patients with cluster headache. J Headache Pain. 2021 Apr 20;22(1):28. doi: 10.1186/s10194-021-01241-7. PMID: 33879041; PMCID: PMC8056539. Láinez MJA, Schoenen J, Stroud C, Bardos J, Bangs M, Kemmer P, Wenzel R, Kuruppu DK, Martinez JM, Oakes TM. Tolerability and safety of galcanezumab in patients with chronic cluster headache with up to 15 months of galcanezumab treatment. Headache. 2022 Jan;62(1):65-77. doi: 10.1111/head.14234. Epub 2021 Nov 22. Erratum in: Headache. 2022 Apr;62(4):536. doi: 10.1111/head.14297. PMID: 34806783; PMCID: PMC9299588. Kim BS, Chung PW, Kim BK, Lee MJ, Chu MK, Ahn JY, Bae DW, Song TJ, Sohn JH, Oh K, Kim D, Kim JM, Park JW, Chung JM, Moon HS, Cho S, Seo JG, Kim SK, Choi YJ, Park KY, Chung CS, Cho SJ. Diagnostic Delay and Its Predictors in Cluster Headache. Front Neurol. 2022 Feb 10;13:827734. doi: 10.3389/fneur.2022.827734. PMID: 35222255; PMCID: PMC8866826. Seng EK, Burish MJ, Fenton BT, Schindler EAD, Zhou B, Phadke MA, Skanderson M, Best R, Lipton RB, Sico JJ. Characteristics of men and women with medically diagnosed cluster headache in a national integrated healthcare system: A Veterans Health Administration cohort study. Headache. 2024 Nov-Dec;64(10):1273-1284. doi: 10.1111/head.14842. Epub 2024 Oct 14. PMID: 39400858. Calandre EP, Ordoñez-Carrasco JL, Slim M, Rico-Villademoros F, Garcia-Leiva JM. Comorbidity of migraine and fibromyalgia in patients with cluster headache: psychological burden and healthcare resource utilization. A cross-sectional study. J Oral Facial Pain Headache. 2024 Mar;38(1):32-39. doi: 10.22514/jofph.2024.004. Epub 2024 Mar 12. PMID: 39788574; PMCID: PMC11774279. Göbel CH, Koch B, Heinze-Kuhn K, Heinze A, Cirkel A, Göbel H. Headache Phenotype and the Psychosocial Burden of Cluster Headaches: An Analysis of Patients Prior to Hospitalization. Pain Ther. 2025 Apr;14(2):753-767. doi: 10.1007/s40122-025-00715-9. Epub 2025 Feb 24. PMID: 39994092; PMCID: PMC11914562. Nock MK, Borges G, Bromet EJ, Alonso J, Angermeyer M, Beautrais A, Bruffaerts R, Chiu WT, de Girolamo G, Gluzman S, de Graaf R, Gureje O, Haro JM, Huang Y, Karam E, Kessler RC, Lepine JP, Levinson D, Medina-Mora ME, Ono Y, Posada-Villa J, Williams D. Cross-national prevalence and risk factors for suicidal ideation, plans and attempts. Br J Psychiatry. 2008 Feb;192(2):98-105. doi: 10.1192/bjp.bp.107.040113. PMID: 18245022; PMCID: PMC2259024. Elser H, Farkas DK, Fuglsang CH, Sørensen ST, Sørensen HT. Risk of Attempted and Completed Suicide in Persons Diagnosed With Headache. JAMA Neurol. 2025 Mar 1 ;82(3):276-284. doi: 10.1001/jamaneurol.2024.4974. PMID: 39899309; PMCID: PMC11791769. Blau JN. Behaviour during a cluster headache. Lancet. 1993 Sep 18;342(8873):723-5. doi: 10.1016/0140-6736(93)91713-v. PMID: 8103827. May A, Bahra A, Büchel C, Frackowiak RS, Goadsby PJ. Hypothalamic activation in cluster headache attacks. Lancet. 1998 Jul 25;352(9124):275-8. doi: 10.1016/S0140-6736(98)02470-2. PMID: 9690407. Canteras NS. The medial hypothalamic defensive system: hodological organization and functional implications. Pharmacol Biochem Behav. 2002 Mar;71(3):481-91. doi: 10.1016/s0091-3057(01)00685-2. PMID: 11830182. Sano K, Mayanagi Y. Posteromedial hypothalamotomy in the treatment of violent, aggressive behaviour. Acta Neurochir Suppl (Wien). 1988;44:145-51. doi: 10.1007/978-3-7091-9005-0_28. PMID: 3066130. Escobar Vidarte OA, Griswold DP, Orozco Mera J, Arango Uribe GJ, Salcedo JC. Deep Brain Stimulation for Severe and Intractable Aggressive Behavior. Stereotact Funct Neurosurg. 2022;100(4):210-213. doi: 10.1159/000521766. Epub 2022 Jan 31. PMID: 35100596. Turecki G. The molecular bases of the suicidal brain. Nat Rev Neurosci. 2014 Dec;15(12):802-16. doi: 10.1038/nrn3839. Epub 2014 Oct 30. PMID: 25354482; PMCID: PMC5293539. Fazel S, Runeson B. Suicide. N Engl J Med. 2020 Jan 16;382(3):266-274. doi: 10.1056/NEJMra1902944. Erratum in: N Engl J Med. 2020 Mar 12;382(11):1078. doi: 10.1056/NEJMx200005. PMID: 31940700; PMCID: PMC7116087. Louter MA, Wilbrink LA, Haan J, van Zwet EW, van Oosterhout WP, Zitman FG, Ferrari MD, Terwindt GM. Cluster headache and depression. Neurology. 2016 Nov 1;87(18):1899-1906. doi: 10.1212/WNL.0000000000003282. Epub 2016 Sep 30. PMID: 27694264. Chesney E, Goodwin GM, Fazel S. Risks of all-cause and suicide mortality in mental disorders: a meta-review. World Psychiatry. 2014 Jun;13(2):153-60. doi: 10.1002/wps.20128. PMID: 24890068; PMCID: PMC4102288. Chincholkar M, Blackshaw S. Suicidality in chronic pain: assessment and management. BJA Educ. 2023 Aug;23(8):320-326. doi: 10.1016/j.bjae.2023.05.005. Epub 2023 Jun 27. PMID: 37465233; PMCID: PMC10350556. de Coo IF, van Oosterhout WPJ, Wilbrink LA, van Zwet EW, Ferrari MD, Fronczek R. Chronobiology and Sleep in Cluster Headache. Headache. 2019 Jul;59(7):1032-1041. doi: 10.1111/head.13567. Epub 2019 May 31. PMID: 31148161; PMCID: PMC6771706. de Coo IF, Naber WC, Wilbrink LA, Haan J, Ferrari MD, Fronczek R. Increased use of illicit drugs in a Dutch cluster headache population. Cephalalgia. 2019 Apr;39(5):626-634. doi: 10.1177/0333102418804160. Epub 2018 Oct 5. PMID: 30290701; PMCID: PMC6484703. Tables Table 1 : Description of selected studies (* FF : face-face, I: internet, MR: medical records / **CHPAWS: cluster headache patients’ association website, HR: health registry, N: neurology clinic, THC: tertiary headache center / CCH: chronic cluster headache, ECH: episodic cluster headache / NR: not reported / SPAC: Spanish speaking America countries) Ref Authors Year Country Study design Data acquisition* Origin of recruitment** Number of subjects Age Men / Women ECH/CCH/ undetermined CH diagnosis 10 Jürgens et al 2011 Germany Case series FF THC and NC 75 NR NR 48/27/0 26 ECH in-bout ICHD-2 11 12 14 Rozen and Fischman 2012 2018 USA Survey I CHPAWS 1134 NR 816/318 NR neurologist 13 Choong et al 2017 USA Survey MR HR 7589 49.97±13.4 4356/3233 NR ICD-9 15 Ji Lee 2019 Corea Case series FF THC 175 38.4±11.1 149/26 154/8/13 all ECH in-bout ICHD-3 16 Koo et al 2021 USA Survey I CHPAWS 100 45.5±12.3 53/47 56/44 ICHD-3 17 Lainez et al 2022 International Clinical trial FF THC 233 44.9±10.9 365/80 0/445/0 ICHD-3 18 Kim et al 2022 Corea Case series FF THC 445 NR 365/80 328/19/98 ICHD-3 19 Seng et al 2024 USA Survey MR HR 24131 NR 21763/2368 NR ICD-9/10 20 Calandre et al 2024 Spain SPAC Survey I CHPAWS 91 44.8±10.8 32/59 NR physician 21 Göbel et al 2024 Germany Survey FF THC 207 48.16±13.6 n? 62.3%/n? 37.7% n 38.2%/n? 61.2% all ECH in-bout ICHD3 Table 2 : Data extracted in selected studies (CH: cluster headache, CCH: chronic cluster headache, C-SSRS: Columbia suicide severity rating scale, ECH: episodic cluster headache, EHR: electronic health records, HIT6: headache impact test, MA: meta-analysis, OR: odds ratio, PHQ9: patient health questionnaire 9 items, SBQ-R: suicidal behavior questionnaire revised) Ref Authors Year Number Subjects Suicidality evaluation Data reported Suicidal Ideation selected rate for MA Suicide Attempts selected rate for MA 10 Jürgens et al 2011 75 One question ‘whether you had thought about death and/or experienced suicidal tendencies’ Lifetime evaluation Response ‘yes’ Total 13/75 17,3% ECH outside-bout 3/22 13.6% ECH in-bout 4/26 15.4% CCH 6/27 22.2% 17.3% no data available 11 12 14 Rozen and Fischman 2012 2018 1134 Two questions ‘think about suicide’ ‘try to commit suicide’ Lifetime evaluation Responses ‘yes’ ‘think about suicide’ n? 55% tobacco exposed vs tobacco non-exposed 57% vs 43%, p=0.003 men vs women 57% vs 52%, NS ‘try to commit suicide’ n? 2% men vs women 2% vs 2%, NS 55% 2% 13 Choong et al 2017 7589 Suicidal-related claims Hospitalization with specific ICD9 codes Suicidal ideation (V6284) Self-inflicted injury (E950-E959) 1 year before 1 year after the first CH claim Claims Suicidal ideation (V6284) 89/7589 1.2% Self-inflicted injury (E950-E959) 15/7589 0.2% 1.2% 0.2% 15 Ji Lee 2019 175 Four questions ‘Have you thought that it was better to die… ?’ ‘Have you thought of killing yourself… ?’ ‘Have you planned suicide… ?’ ‘Have you attempted suicide … C?’ 3 clinical situations: ictal interictal between-bout (only 54 patients) Lifetime evaluation Responses ‘yes’ ‘Have you thought that it was better to die…?’ passive suicidal ideation ictal: 111/175 64.2% interictal: 7/175 4% between-bout: n? 0% ‘Have you thought of killing yourself…?’ active suicidal ideation ictal: 62/175 35.8% interictal: 6/175 3.5% between-bout: n? 1.9% ‘Have you planned suicide…?’ Suicidal plan ictal: 10/175 5.8% interictal:5/175 2.9% between-bout: n? 1.9% ‘Have you attempted suicide …?’ Suicidal attempt ictal: 4/175 2.3% interictal: 2/175 1.2% between-bout: n? 0% ictal suicidality associated with CH duration (10-y) OR 1.91 [1.29-2.83] HIT6 score (10-point) OR 3.42 [2.01-5.04] PHQ9 score (10-point) OR 3.37 [1.93-5.91] interictal suicidality associated with lifetime bouts (per 5) OR 1.20 [1.05-1.38] PHQ9 score (10-point) OR 4.62 [1.73-12.33] 64.2% 2.3% 16 Koo et al 2021 100 Suicidality evaluation tools SBQ-R / C-SSRS 4 items evaluated passive suicidal ideation active suicidal ideation suicidal plan suicide attempt Lifetime evaluation passive suicidal ideation 59/100 59% active suicidal ideation 47/100 47% suicidal plan 25/100 25% ECH vs CCH 16.1% vs 36.4%, p=0.02 Suicide attempt 8/100 8% ECH vs CCH 3.6% vs 3.6%, p=0.07 Suicidal ideation associated with demoralization (OR 6.66 [1.56,28.49]) but not depression (OR 1.89 [0.66,5.46]) 59% 8% 17 Lainez et al 2022 233 Suicidality evaluation tool C-SSRS 2 items evaluated suicidal ideation suicidal behavior Lifetime evaluation suicidal ideation 52/233 22.3% suicidal behavior 9/233 3.9% 22.3% 3.9% 18 Kim et al 2022 445 Two questions ‘ Have you ever thought that it was better to die? ’ ‘ Have you ever attempted suicide? ’ Lifetime evaluation Responses ‘yes’ ‘ Have you ever thought that it was better to die? ’ 93/445 20.9% ‘ Have you ever attempted suicide? ’ 4/445 0.9% suicidal ideation significantly associated with CH diagnostic delay (≥ 7 years) suicide attempts not associated with CH diagnostic delay 20.9% 0.9% 19 Seng et al 2024 24131 Veterans Health Administration EHR data 2 items evaluated suicidal ideation suicide attempt 5 years after CH diagnosis Positive data suicidal ideation 1556/24131 6.5% suicide attempt 335/24131 1.4% suicidal ideation men vs women 8.9% vs 6.2%, p<0.001 Suicide attempt men vs women 2.1% vs 1.3%, p<0.001 6.5% 1.4% 20 Calandre et al 2024 91 9 th item of PHQ9 ‘Thoughts that you would be better off dead or hurting yourself in some way?’ lifetime evaluation Response ‘yes’ ‘Thoughts that you would be better off dead or hurting yourself in some way?’ 62/91 68.1% 68.1% no data available 21 Göbel et al 2025 207 Data of center Kiel headache questionnaire 3 items evaluated occasional suicidal ideation regular suicidal ideation intention to commit suicide lifetime evaluation Responses ‘yes’ occasional suicidal ideation n? 40.5% regular suicidal ideation n? 7,6% intention to commit suicide n? 1.8% 40.5% no data available Table 3 : The Joanna Briggs Institute (JBI) critical appraisal tool for case series Ref Authors Were there clear criteria for inclusion? Was the condition measured in a standard reliable way for all participants? Were valid methods used for identification of the condition for all participants? Did the case series have consecutive inclusion of participants? Did the case series have complete inclusion of participants? Was there clear reporting in the demographic of the participants? Were the outcomes of follow-up results of case clearly reported? Was there clear reporting in the presenting site(s)/clinic(s) demographic information? Was statistical analysis appropriate? 10 Jûrgens et al (2011) yes yes yes yes yes no yes yes yes 15 Ji Lee et al (2019) yes yes yes no no yes yes yes yes 18 Kim et al (2022) yes yes yes yes yes no yes yes yes T able 4 : Oxford Centre for Evidence-Based Medicine (OCEBM) critical appraisal of survey studies Ref Authors (year) Did the study address a clearly focused question issue? Is the study design appropriate for answering the research question? Is the method of selection of subjects clearly described? Could the way the sample was obtained introduce selection bias? Was the sample of subjects’ representative with regard to the population to which the findings will be referred? Was the sample size based on pre-study consideration of statistical power? Was a satisfactory response rate achieved? Are the measurements likely to be valid and reliable? Was the statistical significance assessed? Are the confidence intervals given for the main results? Could there be confounding factors that haven’t been accounted for? Can be results be applied to your organization? 11 Rozen Fischman (2012) yes yes yes no yes no yes yes no no no yes 12 Rozen Fischman (2012) yes yes yes no yes no yes yes yes yes no yes 13 Choong et al yes yes yes no yes no yes yes yes yes no yes (2017) 14 Rozen (2018)) yes yes yes no yes no yes yes yes yes no yes 16 Koo et al (2021) yes yes yes yes yes no yes yes yes yes yes yes 19 Seng et al (2014) yes yes yes yes yes no yes yes yes yes yes yes 20 Calandre er al (2024) yes yes yes yes yes no yes yes yes yes no yes 21 Göbel et al (2024) yes yes yes yes yes no yes yes no no no yes Additional Declarations Competing interest reported. EKVO had received personal fees for consultancy activities from Abbvie RF had no conflict of interest. MLM received personal fees for consultancy activities from: Abbvie/Allergan, Amgen, Eli Lilly, IPSEN, Lundbeck, Novartis, Orion Pharma, Perfood, Pfizer, Reckitt-Benckiser, Teva, UPSA. . Cite Share Download PDF Status: Published Journal Publication published 04 Dec, 2025 Read the published version in The Journal of Headache and Pain → Version 1 posted Editorial decision: Revision requested 11 Aug, 2025 Reviews received at journal 11 Aug, 2025 Reviewers agreed at journal 11 Aug, 2025 Reviews received at journal 06 Aug, 2025 Reviewers agreed at journal 01 Aug, 2025 Reviewers agreed at journal 30 Jul, 2025 Reviewers invited by journal 28 Jul, 2025 Editor assigned by journal 28 Jul, 2025 Submission checks completed at journal 28 Jul, 2025 First submitted to journal 26 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7221366","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":492614467,"identity":"09efc5fd-1a77-4ba2-9948-b55170a436a4","order_by":0,"name":"Elise K Van Obberghen","email":"","orcid":"","institution":"UR2CA-PIN, CHU Nice and Côte d’Azur University","correspondingAuthor":false,"prefix":"","firstName":"Elise","middleName":"K Van","lastName":"Obberghen","suffix":""},{"id":492614468,"identity":"421f94e2-13f6-4180-80da-2306c97f555a","order_by":1,"name":"Roxane Fabre","email":"","orcid":"","institution":"UR2CA - RESPECT, CHU Nice and Côte d’Azur University","correspondingAuthor":false,"prefix":"","firstName":"Roxane","middleName":"","lastName":"Fabre","suffix":""},{"id":492614469,"identity":"a47ac51d-699a-4417-8459-a54edaf4d88a","order_by":2,"name":"Michel Lanteri-Minet","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABE0lEQVRIiWNgGAWjYBACPgglwcDADGHJgdgMDAZAzHwAqxY2BgbGBrgWoBpjhBa2BHxaoACoJbFBAi6HQwv72eMPPu6xYNBt5z34+APDtvT+2T0GzAUFdnIMbLwPsGrhyUtsnPFMgsHsMF+ywQGG27kz7pwxYJ5hkGwMNM4Au8NyDJt5DkjUbzvMYyYB0rJBIsf8N4/BgcQG+TbsDuN/Y9j85wDIFh7zH0At6QYSOQbMQC31DWxs2LVIAG1hgGgxA3r/dgJMSwIDTi1vDGf2QLQYS5wxuG0440ZaAVBLsmEbDi38/DkGH34cqGMwO3/G8ENFxW15/hnJG5h5/tjJ8+PQggaQg4goDaNgFIyCUTAKsAIAlSlR0gSRAZAAAAAASUVORK5CYII=","orcid":"","institution":"UR2CA-PIN, CHU Nice and Côte d’Azur University","correspondingAuthor":true,"prefix":"","firstName":"Michel","middleName":"","lastName":"Lanteri-Minet","suffix":""}],"badges":[],"createdAt":"2025-07-26 13:08:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7221366/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7221366/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s10194-025-02140-x","type":"published","date":"2025-12-04T15:57:34+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":88002434,"identity":"54493f9f-a1e4-4ed0-bdda-eca97d861c7d","added_by":"auto","created_at":"2025-07-31 10:27:37","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":28989,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePRISMA flow diagram studies selection (CH: cluster headache / TACs: trigeminal autonomic cephalalgias)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7221366/v1/29ae1b1cff8e997856863e5e.png"},{"id":88002435,"identity":"fb07dbce-f8ca-4470-8ade-a084cead9243","added_by":"auto","created_at":"2025-07-31 10:27:37","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":46422,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eOverall rates of suicidal ideation (A) and suicide attempts (B) in cluster headache\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7221366/v1/bb20799f56b1f3945c067a5e.png"},{"id":88004169,"identity":"04189dc9-9bb7-42e9-a16f-2d6c5c066ff8","added_by":"auto","created_at":"2025-07-31 10:35:37","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":40932,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eRates of suicidal ideation (A) and suicide attempts (B) in cluster headache with a recruitment in specialized field\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7221366/v1/a3c3424ea64b925c76c6219c.png"},{"id":88004170,"identity":"6ee61dbc-f337-48dc-acd1-652fcbcbd043","added_by":"auto","created_at":"2025-07-31 10:35:37","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":27550,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eRates of suicidal ideation (A) and suicide attempts (B) in cluster headache with a recruitment in non-specialized field\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7221366/v1/9f100e48050dc5808524c534.png"},{"id":97723843,"identity":"9253cefb-3128-4788-925b-b40a8516f238","added_by":"auto","created_at":"2025-12-08 16:08:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2260640,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7221366/v1/aae3e78e-a26b-432c-9c0b-0badf01039ce.pdf"}],"financialInterests":"Competing interest reported. EKVO had received personal fees for consultancy activities from Abbvie\nRF had no conflict of interest.\nMLM received personal fees for consultancy activities from: Abbvie/Allergan, Amgen, Eli Lilly, IPSEN, Lundbeck, Novartis, Orion Pharma, Perfood, Pfizer, Reckitt-Benckiser, Teva, UPSA. .","formattedTitle":"Cluster headache suicidality: a systematic review with a meta-analysis","fulltext":[{"header":"Background","content":"\u003cp\u003eCluster headache (CH), which is the most common of the trigeminal autonomic cephalalgias (TACs), is characterized by attacks of severe to very severe unilateral (orbital, supraorbital and/or temporal) pain lasting from 15 to 180 minutes (when untreated) associated with ipsilateral autonomic symptoms and/or with restlessness or agitation [1]. Attacks occur once every other day to eight times a day with pain-free periods of at least 3 months in episodic CH (ECH) and without remission or with remissions lasting less than 3 months in chronic CH (CCH) [1]. Due to the severity and recurrence of attacks, this primary headache is referred to as a \u0026lsquo;suicidal headache\u0026rsquo; [2] with tragic clinical observations such as that of a 56-year-old male with a history of CCH who,\u0026nbsp;during\u0026nbsp;a nocturnal attack, aimed a shotgun toward his symptomatic eye and fired [3].\u003c/p\u003e\n\u003cp\u003eIt is therefore essential to estimate the rate of suicide attempts associated with the cluster headache. It is also essential to estimate the rate of suicidal ideations in this primary headache because, if most instances of suicidal ideation do not lead to suicide attempts [4],\u0026nbsp;suicidal ideation is a predictor of suicide attempts [5]. Unfortunately, to date, the level of suicidality, considering the rate of suicidal ideation and the rate of suicide attempts, has not been reported in a large representative CH population [6]. It is also likely that suicidality differs according to the severity of the cluster headache, so that interpretation of the results of studies devoted to this component of the CH burden must consider the origin of the patients included in these studies (general population, healthcare claims data, primary care, CH patients\u0026rsquo; association websites, neurology, headache tertiary care).\u003c/p\u003e\n\u003cp\u003eThe aim of our work was to perform a systematic review of data on suicidality associated to CH published up to July 2025. This systematic review includes a meta-analysis considering studies carried out in headache tertiary centers, neurology clinics or via CH patients\u0026rsquo; association websites and those with a broader recruitment from the general population, primary care or via healthcare claims data. This systematic review also includes a comparison of the rates of passive and active suicidal ideation and an identification of determinants of suicidality in CH patients.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines [7]. In accordance with these guidelines, our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (registration number: CRD420251110095).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSearch strategy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA comprehensive search on PubMed database was carried out in July 2025. The search terms were \u0026lsquo;suicidality\u0026rsquo; OR \u0026lsquo;suicide\u0026rsquo; OR \u0026lsquo;suicidal ideation\u0026rsquo; OR \u0026lsquo;suicidal tendencies\u0026rsquo; OR \u0026lsquo;suicidal thoughts\u0026rsquo; OR \u0026lsquo;suicidal plan\u0026rsquo; OR \u0026lsquo;suicidal attempt\u0026rsquo; OR \u0026lsquo;self-injury\u0026rsquo; These were combined with a search for \u0026lsquo;cluster headache\u0026rsquo;. In addition to this electronic search, we screened the reference lists of the selected articles and relevant literature known by the authors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eInclusion criteria were: i) prospective and retrospective studies, case series and survey on suicidality and CH; ii) adult or children subjects with a diagnosis of cluster headache done by a physician or according to International Classification of Headache Disorders (ICHD) criteria or according to the International Classification of Diseases (ICD) ; iii) no restrictions by date; iv) no restrictions by geographical location; v) English language articles. Exclusion criteria were: i) case reports; ii) adult or children subjects with a CH self-diagnosis; iii) studies with less than 10 participants. According to these inclusion/exclusion criteria, two authors (VOE and LMM) independently assessed all title and abstracts for inclusion. Full-text papers were retrieved for articles meeting the eligible criteria and for articles for which these criteria could not be verified solely by the title and abstract. All full-text articles were assessed independently by two authors (VOE and LMM), and disagreement was resolved by discussion to reach consensus.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData extraction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were independently extracted by two authors (VOE and LMM). Data extracted included date, country, study design, recruitment (general population, primary care, healthcare claims data, CH patients\u0026rsquo; association website, neurology clinic, headache tertiary center), methods of data acquisition, population (number of participants, age, men: women ratio, percentage of participants with ECH and CCH), method of CH diagnosis, method to suicidality evaluation, rate of suicidal ideations (passive and active), suicidal plan and suicide attempts. \u0026nbsp;The discrepancies were resolved by discussion to reach consensus amongst VOE and LMM.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRisk of bias (quality) assessment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQuality assessment of studies selected in this systematic review was performed using the Joanna Briggs Institute (JBI) Appraisal Checklist tool [7] for case series studies and the Oxford Centre for Evidence-Based Medicine (OCEBM) critical appraisal tool [8] for survey studies. The studies were independently assessed by two authors (VEO and LMM) and the discrepancies were resolved by discussion to reach consensus.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAnalysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work involved two analyses, one quantitative and one qualitative\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eQuantitative analysis\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe quantitative analysis was based on a meta-analysis.\u0026nbsp;For this meta-analysis, we used the rate of suicidal ideation, considering passive suicidal ideation, and the rate of suicide attempts as indicators of suicidality in patients suffering from CH. \u0026nbsp;The rates of suicidal ideation and suicide attempts with the respective 95% confidence interval (CI) were calculated on the combined numbers in the selected studies.\u0026nbsp;Study heterogeneity was performed using\u0026nbsp;I2 (less than 25% viewed as low heterogeneity, between 25% and 50% as moderate, and\u0026nbsp;over 50% as high heterogeneity). We conducted a meta-analysis of all the selected studies, as\u0026nbsp;well as two other meta-analyses, one including studies from specialized recruitment\u0026nbsp;(CH patients\u0026rsquo; association website, neurology clinic, headache tertiary center) and the other including studies from\u0026nbsp;non-specialized\u0026nbsp;recruitment\u0026nbsp;(general population, primary care, health registry). The metaprop function in the meta package of R-4.3.0 software was used.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eQualitative analysis\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor the studies in which data were available, the quantitative analysis compared the rates of passive and active suicidal ideation. Similarly, for the studies in which data were available, the quantitative analysis sought to identify possible determinants of suicidality in CH patients.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eStudies selected\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe search carried out on data related to suicidality and CH published up to July 2025 is summarized in the PRISMA flow chart presented in Figure 1. This search identified 53 unique articles published between February 1952 and April 2025. All articles were screened by title and abstract and 27 articles were excluded at this stage. Full-text articles were assessed for the remaining 25 articles and finally 12 articles, published between April 2011 and April 2025, were selected for the systematic review (Table 1). \u0026nbsp; Among the selected articles, 3 were from the same study [11,12, 14] and 9 from other studies [10, 13, 15, 16, 17, 18, 19, 20, 21]. Studies were survey studies [11, 12, 13, 14, 16, 19, 20, 21], case series studies [10, 15, 18] and a clinical trial [17]. \u0026nbsp;Two were international studies [17, 20] and the other studies were national studies of which 4 took place in USA [11, 12, 13, 14, 16, 19], 2 in Europe [10, 21] and 2 in Asia [15, 18]. \u0026nbsp;Five of the study cohorts were recruited from tertiary headache centers and neurology clinics [10, 15, 17, 18, 21], 3 were recruited through CH patients\u0026rsquo; association websites [11, 12, 14, 16, 20] and 2 were recruited through healthcare claims data [13, 19]. These selected studies included a total of 34180 subjects (range 75-24131). This whole population was composed of 27703 men, 6195 women and 282 subjects with sex not specified. The form of CH was indicated only 1028 subjects with 586, 331 and 111 corresponding to ECH, CCH and undetermined respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData extracted\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData extracted in the 12 selected articles related to the 10 considered studies are presented in Table 2. All the studies were considered for the quantitative analysis and among them all reported the rate of suicidal ideations [10-21] whereas only 7 studies reported the rate of suicide attempts [11-19]. The rates of passive and active suicidal ideation were specified in two studies [15, 16]\u0026nbsp;and were considered for the qualitative analysis.\u0026nbsp;Six studies presented data related to determinants of suicidality in cluster headache [10, 11, 12, 14, 15, 16, 18, 19] and were considered for the qualitative analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRisk of bias of individual studies\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAssessment of selected case series [10, 15, 18] using Joanna JBI Appraisal Checklist tool is summarized in Table 3 and assessment of selected surveys [11, 12, 13, 14, 16, 19, 20, 21] using OCEBM critical appraisal tool is summarized in Table 4. The clinical trial [17] was evaluated individually. Selected studies were not excluded based on their quality appraisal.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOverall rates of suicidal ideation and suicide attempts in CH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsidering the ten studies (34180 subjects) for which the rate of suicidal ideation was reported, and which were included in the meta-analysis [10-21], I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated at 99.7%. A Forest-plot of the overall rate of suicidal ideation in CH is presented in Figure 2. \u0026nbsp;The overall rate of suicidal ideation in CH was estimated at\u0026nbsp;8.0% (95%CI [7.7; 8.3]).\u003c/p\u003e\n\u003cp\u003eConsidering the seven studies (33807 subjects) included in the meta-analysis [11-19], for which the rate of suicide attempts was reported, the I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated to be 93.8%. Forest-plot of the overall rate of suicide attempts in CH is presented in Figure 2. \u0026nbsp;The overall rate of suicide attempts in CH was estimated at\u0026nbsp;1.2% (95%CI [1.1; 1.3]).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRates of suicidal ideation and suicide attempts in CH according to studies recruitment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSpecialized recruitment\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsidering the 8 studies in which the rate of suicidal ideation was reported, with a specialized recruitment (2460 subjects), and included in the meta-analysis [10-12, 14-18, 20-21], I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated to be 97.2%. A Forest-plot of the rate of suicidal ideation in CH reported in specialized fields is presented in Figure 3A. \u0026nbsp;The rate of suicidal ideation in CH reported in specialized field was estimated at\u0026nbsp;44.6% (95%CI [42.7; 46.6]).\u003c/p\u003e\n\u003cp\u003eConsidering the 5 studies with specialized recruitment (2087 subjects) for which the rate of suicide attempts was reported and included in the meta-analysis [11-12, 14-18], I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated to be 77.5%. Forest-plot of the rate of suicide attempts in CH reported in specialized field is presented in Figure 3B. \u0026nbsp;The rate of suicide attempts in CH reported in specialized field was estimated at\u0026nbsp;5.1% (95%CI [3.9; 6.7]).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eNon-specialized recruitment\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsidering the 2 studies with a non-specialized recruitment (31720 subjects) for which the rate of suicidal ideation was reported, and which were included in the meta-analysis [13, 19], I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated to 99.6%. Forest-plot of the rate of suicidal ideation in CH reported in non-specialized field is presented in Figure 4A. \u0026nbsp;The rate of suicidal ideation in CH reported in non-specialized field was estimated at\u0026nbsp;5.2% (95%CI [4.9; 5.4]).\u003c/p\u003e\n\u003cp\u003eConsidering the 2 studies with a non-specialized recruitment (31720 subjects) for which the rate of suicide attempts was reported, and which were included in the meta-analysis [13, 19], I\u003csup\u003e2\u0026nbsp;\u003c/sup\u003ewas estimated to 98.2%. Forest-plot of the rate of suicide attempts in CH reported in non-specialized field is presented in Figure 4B. \u0026nbsp;The rate of suicide attempts in CH reported in non-specialized field was estimated at\u0026nbsp;1.1% (95%CI [1.0; 1.2]).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of rates of passive suicidal ideation and active suicidal ideation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJi Lee et al showed that the rate of active suicidal ideation was lower than the rate of passive suicidal ideation (35.8% vs. 64.8%) in the ictal phase, whereas its rates were similar in the inter-ictal phase (3.8% vs. 4%) [15]. Regardless of ictal and interictal assessment, Koo et al also found a lower rate of active suicidal ideation than passive suicidal ideation (25% vs 47%) [16]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeterminants of suicidality in CH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe influence of gender on suicidality in CH has been evaluated in two studies [12, 19} with contradictory results. Rozen and Fischman found no statistically significant difference in the rates of suicidal ideation and attempted suicide between men and women [12], whereas Seng et al found significantly higher rates of both in men [19].\u003c/p\u003e\n\u003cp\u003eThe influence of the CH form was evaluated in two studies [10, 16]. J\u0026uuml;rgens et al suggested a higher rate of suicidal ideation in patients suffering from CCH but did not assess its significance [10]. Koo et al found no difference in the rate of suicide attempts according to the form of CH [16].\u003c/p\u003e\n\u003cp\u003eKim et al found a significant association between the rate of suicidal ideation and the delay in diagnosis (\u0026ge; 7 years) but did not find such an association for the rate of suicide attempts [18].\u003c/p\u003e\n\u003cp\u003eIn a detailed study of patients suffering mainly (almost 90%) from ECH, Ji Lee et al showed that the clinical expressivity of CH influenced the rates of suicidal ideation and suicide attempts, which were higher during attacks than between attacks or during periods of remission [15]. In this work, the authors carried out a study of factors associated with suicidality [15] showing that ictal suicidality was associated with the CH duration, the HIT-6 score and the PHQ-9 score, whereas interictal suicidality was associated with the cumulative number of painful bouts and the PHQ-9 score (detailed data in Table 2).\u003c/p\u003e\n\u003cp\u003eIn another association study, Koo et al [16] showed that the rate of suicidal ideation was linked to demoralization (according to\u0026nbsp;demoralization diagnostic criteria for use in psychosomatic research and the Kissane Demoralization Scale)\u0026nbsp;and not to depression (detailed data in table 2).\u003c/p\u003e\n\u003cp\u003eFinally, Rozen showed an association between the rate of suicidal ideation of CH patients and smoking [14].\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSuicide is considered as common in patients with CH, to the point that CH has been defined as \u0026lsquo;suicidal headache\u0026rsquo;. However, the exact level of suicidality is not known and is intuitively assumed to be correlated with the severity of CH. Our main objective was to specify the suicidality associated with CH and to evaluate whether it differed according to whether it was evaluated in a specialized field (with a selection bias in favor of the most severely affected patients) or in a non-specialized field (with a lesser selection bias due to the inclusion of patients of varying severity and being more representative of patients suffering from CH as a whole). \u0026nbsp;To do this, we carried out a systematic review to studies that evaluated the suicidality of CH. We then performed a meta-analysis in three stages: i) for all the studies, ii) for studies carried out in a specialized field (studies with recruitment in a tertiary headache center, a neurological clinic or via the website of a CH patients\u0026rsquo; association) and iii) for studies carried out in a non-specialized field (studies using medical records of heath registry). This meta-analysis assessed at the two extremes of suicidal behavior, i.e. suicidal ideation and suicide attempts.\u0026nbsp;The overall rate of suicidal ideation in CH was estimated at\u0026nbsp;8% (95%CI [7.7; 8.3] and the overall rate of suicide attempts in CH was estimated at\u0026nbsp;1.2% (95%CI [1.1; 1.3]). Meta-analysis performed with studies related to a recruitment in a non-specialized field (which concerned more than 90% of patients included in all selected studies)\u0026nbsp;shows similar results with rate of suicidal ideation and rate of suicide attempts estimated at 5.2% (95%CI [4.9; 5.4]) and 1.1% (95%CI [1.0; 1.2]) respectively. These figures do not seem to indicate a higher overall level of suicidality associated with CH when compared with available epidemiological data on suicidality in the general population. For example, in an analysis of World Mental Health Survey data from 17 countries, the reported cross-national lifetime prevalence (standard error) of suicidal ideation and the reported cross-national lifetime prevalence (standard error) of suicide attempts were 9.2% (0.1) and 2.7% (0.1) respectively [22]. Nevertheless, a recent Danish population-based cohort study, not included in our meta-analysis because it did not individualize patients with CH, showed a suicidal risk increase in subjects diagnosed with TAC (n=6872) compared to matched controls (n=597430) demonstrated by hazards for attempted suicide (HR, 1.97; 95% CI, 1.35-2.87)\u0026nbsp;and for completed suicide (HR, 2.40; 95%CI, 1.23-4.66) [23]\u003c/p\u003e\n\u003cp\u003eOn the other hand, the meta-analysis carried out on the studies recruited from the specialized field revealed a much higher level of suicidality associated with CH with rate of suicidal ideation and rate of suicide attempts estimated at\u0026nbsp;44.6% (95%CI [42.7; 46.6]) and 5.1% (95%CI [3.9; 6.7]) respectively. As assumed by the background of our study, such results argue in favor of a suicidal risk which would concern the most severely affected CH patients. Surprisingly, our systematic review did not find any robust data comparing the suicidality of patients suffering from ECH with that of patients suffering from CCH. On the other hand, Ji Lee et al showed higher rates of suicidal ideation and suicide attempts during CH attacks [15]. Such ictal suicidality may be explained by the extreme severity of the pain, but it could also be part of the behavior observed during CH attacks. Beyond restlessness, which is a diagnostic criterion for CH [1], impulsive self-inflicted injuries have been reported during CH attacks [24]. Such self-aggressiveness could result from the activation of the posterior hypothalamus demonstrated during the CH attack [25]. \u0026nbsp;There is basic evidence for the involvement of the ventro- and dorsomedial as well as the posterior hypothalamus in the pathophysiology of aggressiveness [26] and the posterior hypothalamus has been proposed as a target to treat patients with refractory aggressiveness using hypothalamotomy [27] or deep brain stimulation [28]. Given that\u0026nbsp;the disruption of the hypothalamic\u0026ndash;pituitary\u0026ndash;adrenal axis plays a key biological role in stress reactivity associated with suicidal behavior [29] and that impulsivity is a component of most psychological models of suicide [30], the impulsive aggressiveness observed in CH attacks could be an important precipitating factor of suicidal behavior observed during the ictal phase of the CH [3].\u003c/p\u003e\n\u003cp\u003eCaution is also needed when interpreting the relationship between suicidal risk in CH patients and depressive comorbidity, which is three times more frequent in these patients [31]. Overall, the association seems obvious, especially as it has been well demonstrated that depression, like all other psychiatric disorders, increases the risk of suicide [32]. The results of Ji Lee et al point in this direction, showing a significant association between the PHIQ-9 score and suicidality, whether ictal or interictal [15]. However, in a more detailed study of the psychological determinants of suicidality in CH patients, Koo et al showed that the rate of suicidal ideation was linked to demoralization (according to\u0026nbsp;demoralization diagnostic criteria for use in psychosomatic research and the Kissane Demoralization Scale)\u0026nbsp;and not to depression [16]. Interestingly, Koo et al found that suicidal ideation was associated with depression and not to demoralization in controls [16], suggesting that\u0026nbsp;demoralization may be particularly sensitive to suicidality in CH.\u003c/p\u003e\n\u003cp\u003eOur qualitative analysis has shown that certain determinants of suicidal risk have not been evaluated in studies devoted to this topic. In particular, the association of suicidal risk with sleep disturbances and the use of illicit drugs was not considered, whereas both are pain-related risk factors for suicidality in chronic pain [33]. Sleep disturbances and illicit drug use should therefore be considered in association studies with suicidality, as they are more frequently observed in CH patients than in the general population [34, 35]\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis systematic review showed an overall suicidal risk in CH that may not be significantly higher than in the general population. On the other hand, it showed a clear increase in this risk among CH patients followed up in specialized fields (tertiary care center patients, neurological clinic, patients linked to patients\u0026apos; associations), with almost half of these patients declaring suicidal ideations and more than 5% having made suicide attempts. These patients are a priori the most severely affected by CH, with the highest intensity of pain during attacks, the highest number of attacks and significant depressive comorbidity. Nevertheless, the qualitative analysis carried out in this systematic review suggests that the suicidal behavior observed in CH is more complex, probably involving impulsive aggressiveness during attacks and demoralization. Future studies aimed at clarifying the determinants of suicidal risk in CH will need to integrate all these elements, adding sleep disorders and illicit drug use, two potential determinants that have never been considered to date. Such an approach is essential if we are to develop effective suicide prevention for CH patients.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthic approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis systematic review did not require the authorization of an ethics committee. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (registration number:\u0026nbsp;CRD420251110095).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailable data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysis during the current review are available from the corresponding author on reasonable request\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eVOE had received personal fees for consultancy activities from Abbvie\u003c/p\u003e\n\u003cp\u003eFR had no conflict of interest.\u003c/p\u003e\n\u003cp\u003eLMM received personal fees for consultancy activities from: Abbvie/Allergan, Amgen, Eli Lilly, IPSEN, Lundbeck, Medtronic, Novartis, Orion Pharma, Perfood, Pfizer, Reckitt-Benckiser, Savia, Bioelectronics, Teva, UPSA. .\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by FHU InovPain\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contribution\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eVOE and LMM conceived the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEVO and LMM performed studies selection, data acquisition and data analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFR performed statistical analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEVO and LMM drafted the manuscript. A\u003c/p\u003e\n\u003cp\u003eAll authors revised and approved the final manuscript\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eHeadache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018 Jan;38(1):1-211. doi: 10.1177/0333102417738202. PMID: 29368949.\u003c/li\u003e\n \u003cli\u003eHorton BT. Histaminic cephalgia. J Lancet. 1952 Feb;72(2):92-8. PMID: 14908316.\u003c/li\u003e\n \u003cli\u003eRothrock J. Cluster: a potentially lethal headache disorder. Headache. 2006 Feb;46(2):327. doi: 10.1111/j.1526-4610.2006.00346.x. PMID: 16492244.\u003c/li\u003e\n \u003cli\u003eKlonsky ED, Dixon-Luinenburg T, May AM. The critical distinction between suicidal ideation and suicide attempts. World Psychiatry. 2021 Oct;20(3):439-441. doi: 10.1002/wps.20909. PMID: 34505359; PMCID: PMC8429339.\u003c/li\u003e\n \u003cli\u003eFranklin JC, Ribeiro JD, Fox KR, Bentley KH, Kleiman EM, Huang X, Musacchio KM, Jaroszewski AC, Chang BP, Nock MK. Risk factors for suicidal thoughts and behaviors: A meta-analysis of 50 years of research. Psychol Bull. 2017 Feb;143(2):187-232. doi: 10.1037/bul0000084. Epub 2016 Nov 14. PMID: 27841450.\u003c/li\u003e\n \u003cli\u003eKim SA, Choi SY, Youn MS, Pozo-Rosich P, Lee MJ. Epidemiology, burden and clinical spectrum of cluster headache: a global update. Cephalalgia. 2023 Sep;43(9):3331024231201577. doi: 10.1177/03331024231201577. PMID: 37728577.\u003c/li\u003e\n \u003cli\u003eShamseer L, Moher D, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P, Stewart LA; PRISMA-P Group. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015: elaboration and explanation. BMJ. 2015 Jan 2;350:g7647. doi: 10.1136/bmj.g7647. Erratum in: BMJ. 2016 Jul 21;354:i4086. doi: 10.1136/bmj.i4086. PMID: 25555855.\u003c/li\u003e\n \u003cli\u003eMoola S, Munn Z, Sears K, Sfetcu R, Currie M, Lisy K, Tufanaru C, Qureshi R, Mattis P, Mu P. Conducting systematic reviews of association (etiology): The Joanna Briggs Institute\u0026apos;s approach. Int J Evid Based Healthc. 2015 Sep;13(3):163-9. doi: 10.1097/XEB.0000000000000064. PMID: 26262566.\u003c/li\u003e\n \u003cli\u003eCEBM - Centre for Evidence Based Medicine (2014) Critical AppraisalTools.\u0026nbsp;https:// www. cebm. net/ 2014/ 06/ criti cal- appra isal. Accessed 20 Mar 2025.\u003c/li\u003e\n \u003cli\u003eJ\u0026uuml;rgens TP, Gaul C, Lindwurm A, Dresler T, Paelecke-Habermann Y, Schmidt-Wilcke T, L\u0026uuml;rding R, Henkel K, Leinisch E. Impairment in episodic and chronic cluster headache. Cephalalgia. 2011 Apr;31(6):671-82. doi: 10.1177/0333102410391489. Epub 2010 Dec 1. Erratum in: Cephalalgia. 2011 Apr;31(6):766. PMID: 21123629.\u003c/li\u003e\n \u003cli\u003eRozen TD, Fishman RS. Cluster headache in the United States of America: demographics, clinical characteristics, triggers, suicidality, and personal burden. Headache. 2012 Jan;52(1):99-113. doi: 10.1111/j.1526-4610.2011.02028.x. Epub 2011 Nov 11. PMID: 22077141.\u003c/li\u003e\n \u003cli\u003eRozen TD, Fishman RS. Female cluster headache in the United States of America: what are the gender differences? Results from the United States Cluster Headache Survey. J Neurol Sci. 2012 Jun 15;317(1-2):17-28. doi: 10.1016/j.jns.2012.03.006. Epub 2012 Apr 5. PMID: 22482825.\u003c/li\u003e\n \u003cli\u003eChoong CK, Ford JH, Nyhuis AW, Joshi SG, Robinson RL, Aurora SK, Martinez JM. Clinical Characteristics and Treatment Patterns Among Patients Diagnosed With Cluster Headache in U.S. Healthcare Claims Data. Headache. 2017 Oct;57(9):1359-1374. doi: 10.1111/head.13127. Epub 2017 Jun 5. PMID: 28581025; PMCID: PMC5655925.\u003c/li\u003e\n \u003cli\u003eRozen TD. Cluster Headache Clinical Phenotypes: Tobacco Nonexposed (Never Smoker and No Parental Secondary Smoke Exposure as a Child) versus Tobacco-Exposed: Results from the United States Cluster Headache Survey. Headache. 2018 May;58(5):688-699. doi: 10.1111/head.13295. Epub 2018 Mar 14. PMID: 29536529.\u003c/li\u003e\n \u003cli\u003eJi Lee M, Cho SJ, Wook Park J, Kyung Chu M, Moon HS, Chung PW, Myun Chung J, Sohn JH, Kim BK, Kim BS, Kim SK, Song TJ, Choi YJ, Park KY, Oh K, Ahn JY, Lee KS, Cho S, Chung CS. Increased suicidality in patients with cluster headache. Cephalalgia. 2019 Sep;39(10):1249-1256. doi: 10.1177/0333102419845660. Epub 2019 Apr 24. PMID: 31018651.\u003c/li\u003e\n \u003cli\u003eKoo BB, Bayoumi A, Albanna A, Abusuliman M, Burrone L, Sico JJ, Schindler EAD. Demoralization predicts suicidality in patients with cluster headache. J Headache Pain. 2021 Apr 20;22(1):28. doi: 10.1186/s10194-021-01241-7. PMID: 33879041; PMCID: PMC8056539.\u003c/li\u003e\n \u003cli\u003eL\u0026aacute;inez MJA, Schoenen J, Stroud C, Bardos J, Bangs M, Kemmer P, Wenzel R, Kuruppu DK, Martinez JM, Oakes TM. Tolerability and safety of galcanezumab in patients with chronic cluster headache with up to 15\u0026nbsp;months of galcanezumab treatment. Headache. 2022 Jan;62(1):65-77. doi: 10.1111/head.14234. Epub 2021 Nov 22. Erratum in: Headache. 2022 Apr;62(4):536. doi: 10.1111/head.14297. PMID: 34806783; PMCID: PMC9299588.\u003c/li\u003e\n \u003cli\u003eKim BS, Chung PW, Kim BK, Lee MJ, Chu MK, Ahn JY, Bae DW, Song TJ, Sohn JH, Oh K, Kim D, Kim JM, Park JW, Chung JM, Moon HS, Cho S, Seo JG, Kim SK, Choi YJ, Park KY, Chung CS, Cho SJ. Diagnostic Delay and Its Predictors in Cluster Headache. Front Neurol. 2022 Feb 10;13:827734. doi: 10.3389/fneur.2022.827734. PMID: 35222255; PMCID: PMC8866826.\u003c/li\u003e\n \u003cli\u003eSeng EK, Burish MJ, Fenton BT, Schindler EAD, Zhou B, Phadke MA, Skanderson M, Best R, Lipton RB, Sico JJ. Characteristics of men and women with medically diagnosed cluster headache in a national integrated healthcare system: A Veterans Health Administration cohort study. Headache. 2024 Nov-Dec;64(10):1273-1284. doi: 10.1111/head.14842. Epub 2024 Oct 14. PMID: 39400858.\u003c/li\u003e\n \u003cli\u003eCalandre EP, Ordo\u0026ntilde;ez-Carrasco JL, Slim M, Rico-Villademoros F, Garcia-Leiva JM. Comorbidity of migraine and fibromyalgia in patients with cluster headache: psychological burden and healthcare resource utilization. A cross-sectional study. J Oral Facial Pain Headache. 2024 Mar;38(1):32-39. doi: 10.22514/jofph.2024.004. Epub 2024 Mar 12. PMID: 39788574; PMCID: PMC11774279.\u003c/li\u003e\n \u003cli\u003eG\u0026ouml;bel CH, Koch B, Heinze-Kuhn K, Heinze A, Cirkel A, G\u0026ouml;bel H. Headache Phenotype and the Psychosocial Burden of Cluster Headaches: An Analysis of Patients Prior to Hospitalization. Pain Ther. 2025 Apr;14(2):753-767. doi: 10.1007/s40122-025-00715-9. Epub 2025 Feb 24. PMID: 39994092; PMCID: PMC11914562.\u003c/li\u003e\n \u003cli\u003eNock MK, Borges G, Bromet EJ, Alonso J, Angermeyer M, Beautrais A, Bruffaerts R, Chiu WT, de Girolamo G, Gluzman S, de Graaf R, Gureje O, Haro JM, Huang Y, Karam E, Kessler RC, Lepine JP, Levinson D, Medina-Mora ME, Ono Y, Posada-Villa J, Williams D. Cross-national prevalence and risk factors for suicidal ideation, plans and attempts. Br J Psychiatry. 2008 Feb;192(2):98-105. doi: 10.1192/bjp.bp.107.040113. PMID: 18245022; PMCID: PMC2259024.\u003c/li\u003e\n \u003cli\u003eElser H, Farkas DK, Fuglsang CH, S\u0026oslash;rensen ST, S\u0026oslash;rensen HT. Risk of Attempted and Completed Suicide in Persons Diagnosed With Headache. JAMA Neurol. 2025 Mar 1 ;82(3):276-284. doi: 10.1001/jamaneurol.2024.4974. PMID: 39899309; PMCID: PMC11791769.\u003c/li\u003e\n \u003cli\u003eBlau JN. Behaviour during a cluster headache. Lancet. 1993 Sep 18;342(8873):723-5. doi: 10.1016/0140-6736(93)91713-v. PMID: 8103827.\u003c/li\u003e\n \u003cli\u003eMay A, Bahra A, B\u0026uuml;chel C, Frackowiak RS, Goadsby PJ. Hypothalamic activation in cluster headache attacks. Lancet. 1998 Jul 25;352(9124):275-8. doi: 10.1016/S0140-6736(98)02470-2. PMID: 9690407.\u003c/li\u003e\n \u003cli\u003eCanteras NS. The medial hypothalamic defensive system: hodological organization and functional implications. Pharmacol Biochem Behav. 2002 Mar;71(3):481-91. doi: 10.1016/s0091-3057(01)00685-2. PMID: 11830182.\u003c/li\u003e\n \u003cli\u003eSano K, Mayanagi Y. Posteromedial hypothalamotomy in the treatment of violent, aggressive behaviour. Acta Neurochir Suppl (Wien). 1988;44:145-51. doi: 10.1007/978-3-7091-9005-0_28. PMID: 3066130.\u003c/li\u003e\n \u003cli\u003eEscobar Vidarte OA, Griswold DP, Orozco Mera J, Arango Uribe GJ, Salcedo JC. Deep Brain Stimulation for Severe and Intractable Aggressive Behavior. Stereotact Funct Neurosurg. 2022;100(4):210-213. doi: 10.1159/000521766. Epub 2022 Jan 31. PMID: 35100596.\u003c/li\u003e\n \u003cli\u003eTurecki G. The molecular bases of the suicidal brain. Nat Rev Neurosci. 2014 Dec;15(12):802-16. doi: 10.1038/nrn3839. Epub 2014 Oct 30. PMID: 25354482; PMCID: PMC5293539.\u003c/li\u003e\n \u003cli\u003eFazel S, Runeson B. Suicide. N Engl J Med. 2020 Jan 16;382(3):266-274. doi: 10.1056/NEJMra1902944. Erratum in: N Engl J Med. 2020 Mar 12;382(11):1078. doi: 10.1056/NEJMx200005. PMID: 31940700; PMCID: PMC7116087.\u003c/li\u003e\n \u003cli\u003eLouter MA, Wilbrink LA, Haan J, van Zwet EW, van Oosterhout WP, Zitman FG, Ferrari MD, Terwindt GM. Cluster headache and depression. Neurology. 2016 Nov 1;87(18):1899-1906. doi: 10.1212/WNL.0000000000003282. Epub 2016 Sep 30. PMID: 27694264.\u003c/li\u003e\n \u003cli\u003eChesney E, Goodwin GM, Fazel S. Risks of all-cause and suicide mortality in mental disorders: a meta-review. World Psychiatry. 2014 Jun;13(2):153-60. doi: 10.1002/wps.20128. PMID: 24890068; PMCID: PMC4102288.\u003c/li\u003e\n \u003cli\u003eChincholkar M, Blackshaw S. Suicidality in chronic pain: assessment and management. BJA Educ. 2023 Aug;23(8):320-326. doi: 10.1016/j.bjae.2023.05.005. Epub 2023 Jun 27. PMID: 37465233; PMCID: PMC10350556.\u003c/li\u003e\n \u003cli\u003ede Coo IF, van Oosterhout WPJ, Wilbrink LA, van Zwet EW, Ferrari MD, Fronczek R. Chronobiology and Sleep in Cluster Headache. Headache. 2019 Jul;59(7):1032-1041. doi: 10.1111/head.13567. Epub 2019 May 31. PMID: 31148161; PMCID: PMC6771706.\u003c/li\u003e\n \u003cli\u003ede Coo IF, Naber WC, Wilbrink LA, Haan J, Ferrari MD, Fronczek R. Increased use of illicit drugs in a Dutch cluster headache population. Cephalalgia. 2019 Apr;39(5):626-634. doi: 10.1177/0333102418804160. Epub 2018 Oct 5. PMID: 30290701; PMCID: PMC6484703.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTable 1\u003c/u\u003e\u003c/strong\u003e\u003cstrong\u003e: Description of selected studies (* FF\u0026nbsp;: face-face, I: internet, MR: medical records / **CHPAWS: cluster headache patients\u0026rsquo; association website, HR: health registry, N: neurology clinic, THC: tertiary headache center / CCH: chronic cluster headache, ECH: episodic cluster headache / NR: not reported / SPAC: Spanish speaking America countries)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"878\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRef\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAuthors\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCountry\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eStudy design\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eData acquisition*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOrigin of recruitment**\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber of subjects\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMen\u0026nbsp;/ Women\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eECH/CCH/\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eundetermined\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCH diagnosis\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eJ\u0026uuml;rgens et al \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eGermany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eCase series\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTHC and NC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e48/27/0\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e26 ECH in-bout\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD-2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eRozen and Fischman\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2012\u003c/p\u003e\n \u003cp\u003e2018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eUSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eCHPAWS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e1134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e816/318\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eneurologist\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eChoong et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eUSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eMR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eHR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e7589\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e49.97\u0026plusmn;13.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e4356/3233\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICD-9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eJi Lee\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eCorea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eCase series\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTHC\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e175\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e38.4\u0026plusmn;11.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e149/26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e154/8/13\u003c/p\u003e\n \u003cp\u003eall ECH in-bout\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD-3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eKoo et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eUSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eCHPAWS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e45.5\u0026plusmn;12.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e53/47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e56/44\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD-3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eLainez et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eInternational\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eClinical trial\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTHC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e233\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e44.9\u0026plusmn;10.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e365/80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e0/445/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD-3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eKim et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eCorea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eCase series\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTHC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e445\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e365/80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e328/19/98\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD-3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eSeng et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eUSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eMR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eHR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e24131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e21763/2368\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICD-9/10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eCalandre et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eSpain \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSPAC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eCHPAWS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e44.8\u0026plusmn;10.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e32/59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003ephysician\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eG\u0026ouml;bel et al\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eGermany\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eSurvey\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eFF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 86px;\"\u003e\n \u003cp\u003eTHC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e207\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e48.16\u0026plusmn;13.6\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003en? 62.3%/n? 37.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003en \u0026nbsp;38.2%/n? 61.2%\u003c/p\u003e\n \u003cp\u003eall ECH in-bout\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eICHD3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTable 2\u003c/u\u003e\u003c/strong\u003e\u003cstrong\u003e: Data extracted in selected studies (CH: cluster headache, CCH: chronic cluster headache, C-SSRS: Columbia suicide severity rating scale, ECH: episodic cluster headache, EHR: electronic health records, HIT6: headache impact test, MA: meta-analysis, OR: odds ratio, PHQ9: patient health questionnaire 9 items, SBQ-R: suicidal behavior questionnaire revised)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"658\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRef\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAuthors\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eYear\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eSubjects\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidality\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eevaluation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eData reported\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidal Ideation\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eselected rate for MA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicide\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;Attempts\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eselected rate for MA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eJ\u0026uuml;rgens et al \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2011\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOne question\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;whether you had thought about death and/or experienced suicidal tendencies\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponse \u0026lsquo;yes\u0026rsquo;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eTotal 13/75 17,3%\u003c/p\u003e\n \u003cp\u003eECH outside-bout 3/22 13.6%\u003c/p\u003e\n \u003cp\u003eECH in-bout 4/26 15.4%\u003c/p\u003e\n \u003cp\u003eCCH 6/27 22.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e17.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003eno data available\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eRozen and Fischman\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2012\u003c/p\u003e\n \u003cp\u003e2018\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e1134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTwo questions\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;think about suicide\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;try to commit suicide\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponses \u0026lsquo;yes\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;think about suicide\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003en? 55%\u003c/p\u003e\n \u003cp\u003etobacco exposed vs tobacco non-exposed\u003c/p\u003e\n \u003cp\u003e57% vs 43%, p=0.003\u003c/p\u003e\n \u003cp\u003emen vs women\u003c/p\u003e\n \u003cp\u003e57% vs 52%, NS\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;try to commit suicide\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003en? 2%\u003c/p\u003e\n \u003cp\u003emen vs women\u003c/p\u003e\n \u003cp\u003e2% vs 2%, NS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e55%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e2%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eChoong et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e7589\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidal-related claims\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eHospitalization with specific ICD9 codes\u003c/p\u003e\n \u003cp\u003eSuicidal ideation\u003c/p\u003e\n \u003cp\u003e(V6284)\u003c/p\u003e\n \u003cp\u003eSelf-inflicted injury\u003c/p\u003e\n \u003cp\u003e(E950-E959)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1 year before\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e1 year after\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ethe first CH claim\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u0026nbsp;Claims\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSuicidal ideation\u003c/p\u003e\n \u003cp\u003e(V6284)\u003c/p\u003e\n \u003cp\u003e89/7589 1.2%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSelf-inflicted injury\u003c/p\u003e\n \u003cp\u003e(E950-E959)\u003c/p\u003e\n \u003cp\u003e15/7589 0.2%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e1.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e0.2%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eJi Lee\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e175\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eFour questions\u0026nbsp;\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you thought that it was better to die\u0026hellip;\u0026nbsp;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you thought of killing yourself\u0026hellip;\u0026nbsp;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you planned suicide\u0026hellip;\u0026nbsp;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you attempted suicide\u0026nbsp;\u0026hellip;\u0026nbsp;C?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3 clinical situations:\u003c/p\u003e\n \u003cp\u003eictal\u0026nbsp;\u003c/p\u003e\n \u003cp\u003einterictal\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ebetween-bout\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(only 54 patients)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponses \u0026lsquo;yes\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you thought that it was better to die\u0026hellip;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003epassive suicidal ideation\u003c/p\u003e\n \u003cp\u003eictal: 111/175 64.2%\u003c/p\u003e\n \u003cp\u003einterictal: 7/175 4%\u003c/p\u003e\n \u003cp\u003ebetween-bout: n? 0%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you thought of killing yourself\u0026hellip;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003eactive suicidal ideation\u003c/p\u003e\n \u003cp\u003eictal: 62/175 35.8%\u003c/p\u003e\n \u003cp\u003einterictal: 6/175 3.5%\u003c/p\u003e\n \u003cp\u003ebetween-bout: n? 1.9%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you planned suicide\u0026hellip;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003eSuicidal plan\u003c/p\u003e\n \u003cp\u003eictal: 10/175 5.8%\u003c/p\u003e\n \u003cp\u003einterictal:5/175 2.9%\u003c/p\u003e\n \u003cp\u003ebetween-bout: n? 1.9%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Have you attempted suicide\u0026nbsp;\u0026hellip;?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003eSuicidal attempt\u003c/p\u003e\n \u003cp\u003eictal: 4/175 2.3%\u003c/p\u003e\n \u003cp\u003einterictal: 2/175 1.2%\u003c/p\u003e\n \u003cp\u003ebetween-bout: \u0026nbsp; \u0026nbsp; n? 0%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eictal suicidality\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eassociated with\u003c/p\u003e\n \u003cp\u003eCH duration (10-y)\u003c/p\u003e\n \u003cp\u003eOR 1.91 [1.29-2.83]\u003c/p\u003e\n \u003cp\u003eHIT6 score (10-point)\u003c/p\u003e\n \u003cp\u003eOR 3.42 [2.01-5.04]\u003c/p\u003e\n \u003cp\u003ePHQ9 score (10-point)\u003c/p\u003e\n \u003cp\u003eOR 3.37 [1.93-5.91]\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003einterictal suicidality associated with\u003c/p\u003e\n \u003cp\u003elifetime bouts (per 5)\u003c/p\u003e\n \u003cp\u003eOR 1.20 [1.05-1.38]\u003c/p\u003e\n \u003cp\u003ePHQ9 score (10-point)\u003c/p\u003e\n \u003cp\u003eOR 4.62 [1.73-12.33]\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e64.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e2.3%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eKoo et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSuicidality evaluation tools\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eSBQ-R / C-SSRS\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e4 items evaluated\u003c/p\u003e\n \u003cp\u003epassive suicidal ideation\u003c/p\u003e\n \u003cp\u003eactive suicidal ideation\u003c/p\u003e\n \u003cp\u003esuicidal plan\u003c/p\u003e\n \u003cp\u003esuicide attempt\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003epassive suicidal ideation\u003c/p\u003e\n \u003cp\u003e59/100 59%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eactive suicidal ideation\u003c/p\u003e\n \u003cp\u003e47/100 47%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicidal plan\u003c/p\u003e\n \u003cp\u003e25/100 25%\u003c/p\u003e\n \u003cp\u003eECH vs CCH\u003c/p\u003e\n \u003cp\u003e16.1% vs 36.4%, p=0.02\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSuicide attempt\u003c/p\u003e\n \u003cp\u003e8/100 8%\u003c/p\u003e\n \u003cp\u003eECH vs CCH\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e3.6% vs 3.6%, p=0.07\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSuicidal ideation associated with demoralization\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(OR 6.66 [1.56,28.49])\u0026nbsp;\u003c/p\u003e\n \u003cp\u003ebut not depression\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(OR 1.89 [0.66,5.46])\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e59%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e8%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eLainez et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e233\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eSuicidality evaluation tool\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eC-SSRS\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e2 items evaluated\u003c/p\u003e\n \u003cp\u003esuicidal ideation\u003c/p\u003e\n \u003cp\u003esuicidal behavior\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003esuicidal ideation\u003c/p\u003e\n \u003cp\u003e52/233 22.3%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicidal behavior\u003c/p\u003e\n \u003cp\u003e9/233 3.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e22.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e3.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eKim et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e445\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cu\u003eTwo questions\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u0026lsquo;\u003cem\u003eHave you ever thought that\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eit was better to die?\u003c/em\u003e\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026lsquo;\u003cem\u003eHave you ever attempted suicide?\u003c/em\u003e\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eLifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponses \u0026lsquo;yes\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026lsquo;\u003cem\u003eHave you ever thought that\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003eit was better to die?\u003c/em\u003e\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e93/445 20.9%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026lsquo;\u003cem\u003eHave you ever attempted suicide?\u003c/em\u003e\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e4/445 0.9%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicidal ideation significantly associated with CH diagnostic delay\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(\u0026ge; 7 years)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicide attempts\u0026nbsp;\u003c/p\u003e\n \u003cp\u003enot associated\u003c/p\u003e\n \u003cp\u003ewith CH diagnostic delay\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e20.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e0.9%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eSeng et al\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e24131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVeterans Health\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eAdministration\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eEHR data\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e2 items evaluated\u003c/p\u003e\n \u003cp\u003esuicidal ideation\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicide attempt\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e5 years after CH diagnosis\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003ePositive data\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicidal ideation\u003c/p\u003e\n \u003cp\u003e1556/24131 6.5%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicide attempt\u003c/p\u003e\n \u003cp\u003e335/24131 1.4%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003esuicidal ideation\u003c/p\u003e\n \u003cp\u003emen vs women\u003c/p\u003e\n \u003cp\u003e8.9% vs 6.2%, p\u0026lt;0.001\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSuicide attempt\u003c/p\u003e\n \u003cp\u003emen vs women\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2.1% vs 1.3%, p\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e6.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e1.4%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eCalandre et al\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e9\u003csup\u003eth\u003c/sup\u003e item of PHQ9\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Thoughts that you\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ewould be better off dead or hurting yourself in some way?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003elifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponse \u0026lsquo;yes\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e\u0026lsquo;Thoughts that you\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003ewould be better off dead or hurting yourself in some way?\u0026rsquo;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e62/91 68.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e68.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003eno data available\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 31px;\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eG\u0026ouml;bel et al\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2025\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003e207\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eData of center\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eKiel headache questionnaire\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e3 items evaluated\u003c/p\u003e\n \u003cp\u003eoccasional suicidal ideation\u003c/p\u003e\n \u003cp\u003eregular suicidal ideation\u003c/p\u003e\n \u003cp\u003eintention to commit suicide\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003elifetime evaluation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eResponses \u0026lsquo;yes\u0026rsquo;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eoccasional suicidal ideation\u003c/p\u003e\n \u003cp\u003en? 40.5%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eregular suicidal ideation\u003c/p\u003e\n \u003cp\u003en? 7,6%\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eintention to commit suicide\u003c/p\u003e\n \u003cp\u003en? 1.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e40.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003eno data available\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eTable 3\u003c/u\u003e\u003c/strong\u003e\u003cstrong\u003e: The Joanna Briggs Institute (JBI) critical appraisal tool for case series\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"972\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRef\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAuthors\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWere there clear criteria for inclusion?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas the condition measured in a standard reliable way for all participants?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWere valid methods used for identification of the condition for all participants? \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDid the case series have consecutive inclusion of participants?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDid the case series have complete inclusion of participants?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas there clear reporting in the demographic of the participants?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWere the outcomes of follow-up results of case clearly reported?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas there clear reporting in the presenting site(s)/clinic(s) demographic information?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas statistical analysis appropriate?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003eJ\u0026ucirc;rgens et al\u003c/p\u003e\n \u003cp\u003e(2011)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003eJi Lee et al\u003c/p\u003e\n \u003cp\u003e(2019)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 120px;\"\u003e\n \u003cp\u003eKim et al\u003c/p\u003e\n \u003cp\u003e(2022)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003e\u003cbr\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eT\u003c/strong\u003e\u003cstrong\u003e\u003cu\u003eable 4\u003c/u\u003e\u003c/strong\u003e\u003cstrong\u003e: Oxford Centre for Evidence-Based Medicine (OCEBM) critical appraisal of survey studies\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"980\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRef\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAuthors\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(year)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDid the study address a clearly focused question issue?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIs the study design appropriate for answering the research question?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIs the method of selection of subjects clearly described?\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCould the way the sample was obtained introduce selection bias?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas the sample of subjects\u0026rsquo; representative with regard to the population to which the findings will be referred?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas the sample size based on pre-study consideration of statistical power?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas a satisfactory response rate achieved?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAre the measurements likely to be valid and reliable?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWas the statistical significance assessed?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAre the confidence intervals given for the main results?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCould there be confounding factors that haven\u0026rsquo;t been accounted for?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCan be results be applied to your organization?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eRozen Fischman\u003c/p\u003e\n \u003cp\u003e(2012)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eRozen Fischman\u003c/p\u003e\n \u003cp\u003e(2012)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;yes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eChoong et al\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e(2017)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eRozen\u003c/p\u003e\n \u003cp\u003e(2018))\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eKoo et al\u003c/p\u003e\n \u003cp\u003e(2021)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eSeng et al\u003c/p\u003e\n \u003cp\u003e(2014)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eCalandre er al\u003c/p\u003e\n \u003cp\u003e(2024)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003eG\u0026ouml;bel et al\u003c/p\u003e\n \u003cp\u003e(2024)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eno\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eyes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"the-journal-of-headache-and-pain","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tjhp","sideBox":"Learn more about [The Journal of Headache and Pain](https://thejournalofheadacheandpain.biomedcentral.com/)","snPcode":"10194","submissionUrl":"https://submission.nature.com/new-submission/10194/3","title":"The Journal of Headache and Pain","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"cluster headache, suicidal ideation, suicide attempts, burden","lastPublishedDoi":"10.21203/rs.3.rs-7221366/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7221366/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eSuicide is considered as common in patients with cluster headache (CH) and is defined as ‘suicidal headache’. However, the exact level of suicidality is not known and is intuitively assumed to be correlated with the CH severity.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eThis work is a systematic review of data accessible through PubMed and published up to July 25, focusing on the suicidality of CH according to the rates of suicidal ideation and suicide attempts. This meta-analysis was carried out with all selected studies then by considering studies with specialized recruitment and studies with non-specialized recruitment. A qualitative analysis was performed to identify determinants of CH suicidality.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Among the 53 publications identified, 12 were selected corresponding to 10 studies. These selected studies included a total of 34180 subjects (range 75-24131). Eight were performed in a specialized field (headache tertiary center, neurology clinic or via CH patients’ association) and 2 in a non-specialized field (via heath registry). The overall rate of suicidal ideation in CH was estimated at 8.0% (95%CI [7.7; 8.3] and overall rate of suicide attempts in CH was estimated at 1.2% (95%CI [1.1; 1.3]). In a non-specialized field, these rates were estimated at 5.2% (95%CI [4.9; 5.4]) and 1.1% (95%CI [1.0; 1.2]) respectively. In specialized field, these rates were estimated at 44.6% (95%CI [42.7; 46.6]) and 5.1% (95%CI [3.9; 6.7]) respectively. The qualitative analysis showed that few determinants have been considered but it appears that the risk is greater during CH attacks, and it involves psychological determinants such as demoralization.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u0026nbsp;\u003c/strong\u003eThe overall suicidal risk in CH does not appear to be higher than that of the general population, but there is a suicidal risk increase among CH patients followed up in specialized field. This higher risk is indeed probably related to the severity of CH in terms of pain, but it is also probably related to other factors such as impulsive aggressiveness during CH attacks and psychological factors such as demoralization.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRegistration: \u003c/strong\u003eThe systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 07/22/2025 (number: CRD420251110095).\u003c/p\u003e","manuscriptTitle":"Cluster headache suicidality: a systematic review with a meta-analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-31 10:27:32","doi":"10.21203/rs.3.rs-7221366/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-11T10:22:41+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-11T10:13:03+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"11519251668745568876367829167874844631","date":"2025-08-11T09:55:44+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-06T21:50:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"295113018379692045709179074898763486621","date":"2025-08-01T20:18:27+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"128461004901881160906461741476350792155","date":"2025-07-30T21:54:14+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-28T16:17:23+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-28T11:59:23+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-28T11:56:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"The Journal of Headache and Pain","date":"2025-07-26T12:55:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"the-journal-of-headache-and-pain","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tjhp","sideBox":"Learn more about [The Journal of Headache and Pain](https://thejournalofheadacheandpain.biomedcentral.com/)","snPcode":"10194","submissionUrl":"https://submission.nature.com/new-submission/10194/3","title":"The Journal of Headache and Pain","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"95dc4738-dd6c-4eea-9252-ccc03d52d819","owner":[],"postedDate":"July 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-08T16:01:04+00:00","versionOfRecord":{"articleIdentity":"rs-7221366","link":"https://doi.org/10.1186/s10194-025-02140-x","journal":{"identity":"the-journal-of-headache-and-pain","isVorOnly":false,"title":"The Journal of Headache and Pain"},"publishedOn":"2025-12-04 15:57:34","publishedOnDateReadable":"December 4th, 2025"},"versionCreatedAt":"2025-07-31 10:27:32","video":"","vorDoi":"10.1186/s10194-025-02140-x","vorDoiUrl":"https://doi.org/10.1186/s10194-025-02140-x","workflowStages":[]},"version":"v1","identity":"rs-7221366","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7221366","identity":"rs-7221366","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}