Headaches During Hemodialysis: A Neglected Yet Prevalent Syndrome

Headaches During Hemodialysis: A Neglected Yet Prevalent Syndrome | 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 Headaches During Hemodialysis: A Neglected Yet Prevalent Syndrome Anapalli Sunnesh Reddy, Annadata Kumar Chakravarthy, Bindu Menon, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7454831/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Headache is a frequently reported symptom among hemodialysis (HD) patients, with 28–73% experiencing dialysis-related headaches (DH). Despite its high prevalence, DH remains under-recognised and poorly understood. Various factors such as changes in blood pressure, electrolyte imbalances, and dialysate composition have been implicated in its pathophysiology. The present study aimed to assess the frequency and clinical characteristics of dialysis headache in HD patients. Materials & Methods A prospective observational study was conducted on 102 HD patients at a tertiary care centre in South India. Patient data were collected using a standardised questionnaire based on ICHD criteria. Blood samples were drawn pre-heparinization for biochemical analysis. Headache characteristics were documented, and statistical analyses were conducted using t-tests, chi-square, and correlation methods, with p < 0.05 considered significant. Results The mean age was 53.4 ± 13.5 years; 59.8% were male. Most patients (63.7%) underwent dialysis thrice weekly. Headache was reported by 28.4% during dialysis, commonly in the temporal region and mostly in the final hour of treatment. The most frequent headache severity scores were 4 and 5. Systolic blood pressure during headache episodes showed a significant positive correlation with headache severity (r = 0.202, p = 0.042). No significant associations were found with serum sodium, potassium, or DBP. Conclusion Dialysis headache is common and often correlates with elevated intradialytic SBP. Monitoring and managing intradialytic hemodynamics may help alleviate DH. Dialysis headache hemodialysis blood pressure serum electrolytes intradialytic symptoms headache severity Introduction Headache is a common symptom experienced during haemodialysis, affecting approximately 70% of patients, with estimates indicating that 28% to 73% may suffer specifically from dialysis-related headaches.(1,2) Although the exact pathophysiology remains unclear, several contributing factors have been identified(3–5). These include the type of dialysis solution used—acetate-based solutions are more likely to cause headaches than bicarbonate-based ones—as well as fluctuations in urea, sodium, and magnesium levels, and changes in arterial blood pressure during dialysis. Additionally, elevated levels of calcitonin gene-related peptide (CGRP) and substance P during treatment have been implicated. A key mechanism may involve the blood-brain barrier: the osmotic gradient created between the brain and blood during dialysis can lead to the movement of free water into the brain, potentially causing cerebral oedema and resulting in headache.d(6–9) The exact pathophysiology of dialysis-related headache remains unclear, but several contributing factors have been identified. These include sudden changes in blood pressure during dialysis, low serum magnesium levels, and elevated calcium or magnesium concentrations in the dialysate. Additional potential causes include caffeine withdrawal (as caffeine may be removed during dialysis), the use of acetate-based dialysate, intradialytic hypotension or hypertension, and exposure to contaminants like fluoride or chloramine in the dialysate. Hard water syndrome, resulting from excessive calcium or magnesium levels in the dialysate—exceeding the AAMI-recommended limits of ≤2 mg/L for calcium and ≤4 mg/L for magnesium—may also play a role. Furthermore, transient changes in serotonin levels, cerebral vasoconstriction, hypoxemia, and alterations in the renin-angiotensin-aldosterone system are believed to contribute to the development of dialysis-related headaches.(10) Although dialysis headache is highly prevalent, it remains an under-researched condition. This lack of sufficient study hinders the ability to clearly identify its clinical features, understand its underlying pathophysiological mechanisms, and establish effective strategies for its management. The present study aimed to assess the frequency and clinical characteristics of dialysis headache (DH) in haemodialysis patients. Study objectives are: To study the prevalence and clinical characteristics of DH in haemodialysis patients. To study the association between blood pressure and dialysis headache in HD patients. To study the association of serum electrolytes and dialysis headache in HD patients. Material & Method This prospective observational study included patients from a single centre in South India- 102 patients on HD out of 324 patients were included in the study. Written informed consent was obtained from all the participants. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College: IEC/NMC/16 th May 2025/16. All patients were on standard bicarbonate HD, performed twice/thrice weekly for 4 hours, using polysulfone dialysers. Hemodialysis vintage ranged from 3 months to 60 months. All the patients were treated with recombinant human erythropoietin. All patients were included after written informed consent for participation in the study. All patients were interviewed using a questionnaire based on the international headache classification diagnostic criteria. The questionnaire consisted of details on the time of headache onset, monthly incidence of symptoms, pain severity assessed on verbal analogue scale (0 representing “no pain”, 10 representing “the strongest pain” as estimated by the patient), quality of pain, location, lateralisation, duration of pain, associated symptoms, time of onset after initiation of haemodialysis and treatment. All patients with multiple episodes of headache were subjected to a thorough neurological exam and tests if clinically indicated. Blood sample was collected before heparin administration for BUN, Serum creatinine, serum sodium, serum potassium, serum magnesium, serum calcium, serum phosphate and serum albumin. Statistical analysis: All continuous variables were tested for normal distribution with the Kolmogorov-Smirnov test. Normally distributed values were presented as mean ±standard deviation, whereas non-normally distributed values were presented as median (interquartile range). Categorical values were presented as numbers and percentages. Results were statistically analysed with a chi-square test, t-test for parametric and Mann-Whitney test for non-parametric data. P <0.05 was considered significant. Ethical Consideration: Written informed consent was obtained for anonymised patient information to be published in this article. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College, IEC/NMC/16 th May 2025/16. Result Present study included total of 102 patients fulfilling inclusion criteria with mean age of 53.4±13.5yrs age. Table 1 showing the mean characteristics of blood pressure, electrolyte levels, renal profile parameters among patients. Table 1:Mean age of patients with baseline characteristics Parameters Mean SD Age 53.4 13.5 Pre HD SBP 154.0 19.6 Pre HD DBP 80.6 11.0 Post HD SBP 141.9 18.8 Post HD DBP 75.0 10.2 Serum creatinine 6.75 2.27 Serum potassium 4.86 0.71 Blood urea 100.6 37.5 Serum sodium 137.1 3.7 Serum calcium 8.7 0.6 Serum phosphate 4.6 1.6 Serum Albumin 3.8 0.4 Hemoglobin 9.7 1.7 SBP during Headache 163.6 23.3 DBP during headache 85.4 11.6 Table 2: Distribution according to gender and comorbidities Count Column N % Sex Female 41 40.2% Male 61 59.8% Hypertension No 1 1.0% Yes 101 99.0% Diabetes No 48 47.1% Yes 54 52.9% Other co-morbidities Coronary artery disease 11 10.8% Hypothyroidism 11 10.8% None 80 78.4% Among 102 patients, 40.2% were female and 59.8% were male, with marginal male preponderance in the study. The hypertension was present in 99% of cases, diabetes in 52.9% and other comorbidities were present in 21.6% of cases. Table 3: Showing the variables details Count N % Dialysis characteristics Frequency of HD Weekly once 1 1.0% Once every 5 days 1 1.0% Twice a week 35 34.3% thrice a week 65 63.7% Dialyzer reuse First use 70 68.6% Re use 32 31.4% Presence of headache before starting dialysis No 78 76.5% Yes 24 23.5% Headache associated with first dialysis session Maybe 7 6.9% No 66 64.7% Yes 29 28.4% Site of headache Frontal 26 25.5% Fronto-parietal 12 11.8% Frontotemporal 19 18.6% Occipital 8 7.8% Parietal 4 3.9% Temporal 33 32.4% Time between start of HD and onset of headache First 1 hour 5 4.9% First 30 min 27 26.5% First 30min 1 1.0% Last 1 hour 62 60.8% Last 30 min 1 1.0% Post dialysis 6 5.9% Severity of headache: scale of 1 to 10 2 1 1.0% 3 8 7.8% 4 22 21.6% 5 22 21.6% 6 20 19.6% 7 6 5.9% 8 13 12.7% 9 9 8.8% 10 1 1.0% Treatment of current headache Paracetamol 92 90.2% Tramadol 10 9.8% Past history of headache No 75 73.5% Yes 27 26.5% Past headache characteristic Cluster headache 1 1.0% Migraine 3 2.9% Not applicable 72 70.6% Tension headache 26 25.5% Among the 102 patients undergoing hemodialysis (HD), the majority (63.7%) received dialysis thrice a week, followed by 34.3% who underwent it twice weekly. Most patients (68.6%) used a fresh dialyser, while 31.4% reused theirs. Headache before starting dialysis was reported by 23.5% of patients. During the first dialysis session, 28.4% experienced headaches, while 64.7% did not. The most common headache site was the temporal region (32.4%), followed by frontal (25.5%) and frontotemporal (18.6%) areas. Most headaches began in the last hour of dialysis (60.8%), with 26.5% occurring in the first 30 minutes. Headache severity varied, with the most frequently reported scores being 4 and 5 (each 21.6%), and a small proportion reporting extreme severity (score of 10: 1%). Paracetamol was the most commonly used treatment (90.2%), while 9.8% used tramadol. A history of headache was noted in 26.5% of patients, predominantly tension-type headaches (25.5%), with a few cases of migraine (2.9%) and cluster headaches (1.0%). Table 4: Association of headache severity with blood pressure Correlations Headache (severity scale) Pre HD SBP" r 0.122 p-value 0.222 Post HD SBP r 0.071 p-value 0.480 SBP during Headache r 0.202 * p-value 0.042 Pre HD DBP r -0.084 p-value 0.401 Post HD DBP r -0.071 p-value 0.479 DBP during headache r -0.074 p-value 0.459 Serum potassium r -0.001 p-value 0.991 Serum sodium r -0.105 p-value 0.295 The correlation analysis between headache severity (on a scale) and various hemodynamic and biochemical parameters showed that systolic blood pressure (SBP) during the headache had a statistically significant positive correlation with headache severity (r = 0.202, *p = 0.042), suggesting that higher SBP during a headache episode may be associated with more severe headache. However, no significant correlations were found between headache severity and pre- or post-hemodialysis SBP, diastolic blood pressure (DBP) at any point, or serum levels of potassium and sodium, as all respective p-values were > 0.05. Discussion Headache is a frequently reported complication during haemodialysis, affecting up to 70% of patients, with 28–73% experiencing dialysis-specific headaches. Despite its high prevalence, the exact pathophysiology remains poorly understood. Contributing factors include the use of acetate-based dialysate, rapid shifts in blood pressure, and fluctuations in serum urea, sodium, and magnesium levels. Other possible triggers include caffeine withdrawal, hypoxemia, hard water syndrome (elevated calcium/magnesium in dialysate), and exposure to dialysate contaminants like fluoride or chloramine. Neurochemical changes—such as altered levels of CGRP, substance P, and serotonin—and osmotic shifts across the blood-brain barrier leading to cerebral oedema may also play key roles. The present study included a total of 102 patients fulfilling the inclusion criteria with a mean age of 53.4 ± 13.5yrs years. Table 1 shows the mean characteristics of blood pressure, electrolyte levels, and renal profile parameters among patients. 40.2% were female and 59.8% were male, with a marginal male preponderance in the study. The hypertension was present in 99% of cases, diabetes in 52.9% and other comorbidities were present in 21.6% of cases. In a similar study by Sousa M et al., with mean age was 51.8 years (± 13.6); 50% were women; 53% were married( 2 ). Also, in a study by Caplin et al., 54 per cent of the cohort were male, median age of 64 years.( 11 ) Among 102 hemodialysis patients, most (63.7%) underwent dialysis thrice weekly, and 68.6% used a fresh dialyser. Headaches were reported by 23.5% before dialysis and by 28.4% during the first session, with the temporal region being the most common site (32.4%). Headaches mostly began in the last hour of dialysis (60.8%) and were commonly rated at moderate severity (scores 4 and 5, each 21.6%). Paracetamol was the primary treatment (90.2%). A past headache history was seen in 26.5%, mainly tension-type headaches (25.5%). In a study by Sousa et al., 76 patients with primary headaches: 25 with migraine and 51 with tension-type headache. Anxiety was present in 28% and depression in 25%.( 2 ) In a study by Caplin et al., Fatigue was the most commonly reported symptom among patients undergoing dialysis, affecting 82% of them, followed by intradialytic hypotension (76%), muscle cramps (74%), and dizziness (63%). Other frequently experienced symptoms included headache (54%), pruritus (52%), and backache (51%). Fatigue occurred in approximately 50% of dialysis sessions, while hypotension and cramps were present in about 30% of sessions. In terms of post-dialysis recovery, 23% of patients felt better within minutes, 34% recovered by the time they reached home, 16% by bedtime, 24% by the following morning, and 3% only regained their usual state just before the next dialysis session.( 11 ) The correlation analysis between headache severity (on a scale) and various hemodynamic and biochemical parameters showed that systolic blood pressure (SBP) during the headache had a statistically significant positive correlation with headache severity (r = 0.202, *p = 0.042), suggesting that higher SBP during a headache episode may be associated with more severe headache. However, no significant correlations were found between headache severity and pre- or post-hemodialysis SBP, diastolic blood pressure (DBP) at any point, or serum levels of potassium and sodium, as all respective p-values were > 0.05. In a similar study by Goksan B et al., the most common location of headache pain was fronto-temporal, reported by 50% of patients, followed by occipital pain in 27% and diffuse pain in 23%. The majority of patients (87%) described the headache as throbbing in nature, while the remaining 13% experienced a dull type of pain. Regarding intensity, 73% of the headaches were of moderate severity and 27% were severe. In terms of duration, 63% of patients reported that their headaches lasted less than 4 hours, while 37% experienced headaches lasting between 4 and 24 hours. ( 5 ) Among patients with haemodialysis headache (HDH), 41.67% (n = 20; P = 0.003) had a pre-existing headache disorder before starting dialysis, while the majority (58.33%) developed HDH de novo after beginning treatment. The average severity of pain, measured using the Visual Analogue Scale (VAS), was 4.5 ± 1.74, with a median score of 4.5 (interquartile range: 3–7). Patients who experienced HDH had a higher mean score of 7.56 ± 4.51 on the Patient Health Questionnaire-9 (PHQ-9), indicating greater depressive symptoms, compared to a mean score of 2.58 ± 1.63 among those without dialysis-related headaches in a study by Chhaya K et al. ( 12 ) Conclusion This study aimed to assess the frequency and clinical characteristics of dialysis headache (DH) in patients undergoing haemodialysis, along with its associations with blood pressure and serum electrolytes. Among the 102 patients included, the prevalence of dialysis headache was 28.4% during the first dialysis session, with most headaches occurring in the last hour of dialysis and commonly affecting the temporal, frontal, and frontotemporal regions. The majority of headaches were of moderate severity, and paracetamol was the primary treatment used. A history of headache was seen in over a quarter of patients, mostly tension-type. A statistically significant positive correlation was found between systolic blood pressure (SBP) during the headache and headache severity (r = 0.202, p = 0.042), indicating that elevated SBP may contribute to more intense headache episodes during dialysis. However, no significant associations were observed between dialysis headache and pre- or post-dialysis SBP, diastolic blood pressure, or serum levels of sodium and potassium. These findings suggest that intradialytic hemodynamic fluctuations, particularly elevated SBP during episodes, may play a key role in the pathophysiology of dialysis headache, while electrolyte levels appear less influential. Overall, the study underscores the importance of monitoring intradialytic blood pressure to better understand and manage DH in haemodialysis patients. Abbreviations HD: Haemodialysis SBP: Systolic Blood Pressure DBP: Diastolic Blood Pressure Declarations Written informed consent was obtained for anonymised patient information to be published in this article. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College: IEC/NMC/16 th May 2025/16. Consent for publication was obtained from all participants after ensuring anonymity. Availability of data and materials: Not applicable. Funding: Nil Conflict of interest: Nil Authors’ contributions: A Sunnesh Reddy: conceptualisation, study design and data analysis and manuscript drafting and final approval of manuscript. Annadata Kumar Chakravarthy: Data collection, review and editing of manuscript. Bindu Menon: Data collection, manuscript drafting, critical review and editing and final approval of manuscript. Namesh Kamat: Study design, data collection, data analysis and interpretation, manuscript drafting and final approval of manuscript. Acknowledgement: None. References Sousa Melo E, Carrilho Aguiar F, Sampaio Rocha-Filho PA. Dialysis Headache: A Narrative Review. Headache. 2017 Jan;57(1):161–4. Sousa Melo E, Pedrosa RP, Carrilho Aguiar F, Valente LM, Sampaio Rocha-Filho PA. Dialysis headache: characteristics, impact and cerebrovascular evaluation. Arquivos de neuro-psiquiatria. 2022 Feb;80(2):129–36. Antoniazzi AL, Bigal ME, Bordini CA, Speciali JG. Headache associated with dialysis: the International Headache Society criteria revisited. Cephalalgia : an international journal of headache. 2003 Mar;23(2):146–9. Goksel BK, Torun D, Karaca S, Karatas M, Tan M, Sezgin N, et al. Is low blood magnesium level associated with hemodialysis headache? Headache. 2006 Jan;46(1):40–5. Göksan B, Karaali-Savrun F, Ertan S, Savrun M. Haemodialysis-related headache. Cephalalgia : an international journal of headache. 2004 Apr;24(4):284–7. Gozubatik-Celik G, Uluduz D, Goksan B, Akkaya N, Sohtaoglu M, Uygunoglu U, et al. Hemodialysis-related headache and how to prevent it. European journal of neurology. 2019;26(1):100–5. Bana DS, Yap AU, Graham JR. Headache during hemodialysis. Headache. 1972 Apr;12(1):1–14. Alessandri M, Massanti L, Geppetti P, Bellucci G, Cipriani M, Fanciullacci M. Plasma changes of calcitonin gene-related peptide and substance P in patients with dialysis headache. Cephalalgia : an international journal of headache. 2006 Nov;26(11):1287–93. Zepeda-Orozco D, Quigley R. Dialysis disequilibrium syndrome. Pediatric nephrology (Berlin, Germany). 2012 Dec;27(12):2205–11. Leonard H, Pile T. Hard water syndrome: a case series of 30 patients from a London haemodialysis unit. Clinical kidney journal. 2020 Feb;13(1):111–2. Caplin B, Kumar S, Davenport A. Patients’ perspective of haemodialysis-associated symptoms. Nephrology Dialysis Transplantation. 2011;26(8):2656–63. Chhaya KT, Mankad S, Shah MK, Patel M, Desai D, Desai SD. Headache associated with hemodialysis in patients with end-stage renal disease in India: A common yet overlooked comorbidity. Annals of Indian Academy of Neurology. 2022;25(1):82–7. Additional Declarations No competing interests reported. Supplementary Files headacheinhdResponses.xlsx Cite Share Download PDF Status: Posted Version 1 posted 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. 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affecting approximately 70% of patients, with estimates indicating that 28% to 73% may suffer specifically from dialysis-related headaches.(1,2) Although the exact pathophysiology remains unclear, several contributing factors have been identified(3–5). These include the type of dialysis solution used—acetate-based solutions are more likely to cause headaches than bicarbonate-based ones—as well as fluctuations in urea, sodium, and magnesium levels, and changes in arterial blood pressure during dialysis. Additionally, elevated levels of calcitonin gene-related peptide (CGRP) and substance P during treatment have been implicated. A key mechanism may involve the blood-brain barrier: the osmotic gradient created between the brain and blood during dialysis can lead to the movement of free water into the brain, potentially causing cerebral oedema and resulting in headache.d(6–9)\u003c/p\u003e\n\u003cp\u003eThe exact pathophysiology of dialysis-related headache remains unclear, but several contributing factors have been identified. These include sudden changes in blood pressure during dialysis, low serum magnesium levels, and elevated calcium or magnesium concentrations in the dialysate. Additional potential causes include caffeine withdrawal (as caffeine may be removed during dialysis), the use of acetate-based dialysate, intradialytic hypotension or hypertension, and exposure to contaminants like fluoride or chloramine in the dialysate. Hard water syndrome, resulting from excessive calcium or magnesium levels in the dialysate—exceeding the AAMI-recommended limits of ≤2 mg/L for calcium and ≤4 mg/L for magnesium—may also play a role. Furthermore, transient changes in serotonin levels, cerebral vasoconstriction, hypoxemia, and alterations in the renin-angiotensin-aldosterone system are believed to contribute to the development of dialysis-related headaches.(10)\u003c/p\u003e\n\u003cp\u003eAlthough dialysis headache is highly prevalent, it remains an under-researched condition. This lack of sufficient study hinders the ability to clearly identify its clinical features, understand its underlying pathophysiological mechanisms, and establish effective strategies for its management.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe present study aimed to\u0026nbsp;\u003c/strong\u003eassess the frequency and clinical characteristics of dialysis headache (DH) in haemodialysis patients. \u003cstrong\u003eStudy objectives are:\u0026nbsp;\u003c/strong\u003eTo study the prevalence and clinical characteristics of DH in haemodialysis patients. To study the association between blood pressure and dialysis headache in HD patients. To study the association of serum electrolytes and dialysis headache in HD patients.\u003c/p\u003e"},{"header":"Material \u0026 Method","content":"\u003cp\u003eThis prospective observational study included patients from a single centre in South India- 102 patients on HD out of 324 patients were included in the study. Written informed consent was obtained from all the participants. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College: IEC/NMC/16\u003csup\u003eth\u003c/sup\u003e May 2025/16. All patients were on standard bicarbonate HD, performed twice/thrice weekly for 4 hours, using polysulfone dialysers. Hemodialysis vintage ranged from 3 months to 60 months. All the patients were treated with recombinant human erythropoietin. All patients were included after written informed consent for participation in the study.\u003c/p\u003e\n\u003cp\u003eAll patients were interviewed using a questionnaire based on the international headache classification diagnostic criteria. The questionnaire consisted of details on the time of headache onset, monthly incidence of symptoms, pain severity assessed on verbal analogue scale (0 representing “no pain”, 10 representing “the strongest pain” as estimated by the patient), quality of pain, location, lateralisation, duration of pain, associated symptoms, time of onset after initiation of haemodialysis and treatment. All patients with multiple episodes of headache were subjected to a thorough neurological exam and tests if clinically indicated.\u003c/p\u003e\n\u003cp\u003eBlood sample was collected before heparin administration for BUN, Serum creatinine, serum sodium, serum potassium, serum magnesium, serum calcium, serum phosphate and serum albumin.\u003c/p\u003e\n\u003cp\u003eStatistical analysis: All continuous variables were tested for normal distribution with the Kolmogorov-Smirnov test. Normally distributed values were presented as mean ±standard deviation, whereas non-normally distributed values were presented as median (interquartile range). Categorical values were presented as numbers and percentages. Results were statistically analysed with a chi-square test, t-test for parametric and Mann-Whitney test for non-parametric data. P \u0026lt;0.05 was considered significant.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Consideration:\u003c/strong\u003e Written informed consent was obtained for anonymised patient information to be published in this article. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College, IEC/NMC/16\u003csup\u003eth\u003c/sup\u003e May 2025/16.\u003c/p\u003e"},{"header":"Result","content":"\u003cp\u003ePresent study included total of 102 patients fulfilling inclusion criteria with mean age of 53.4\u0026plusmn;13.5yrs age. Table 1 showing the mean characteristics of blood pressure, electrolyte levels, renal profile parameters among patients.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 1:Mean age of patients with baseline characteristics\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eParameters\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e53.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e13.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003ePre HD SBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e154.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e19.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003ePre HD DBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e80.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e11.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003ePost HD SBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e141.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e18.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003ePost HD DBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e75.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e10.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum creatinine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e6.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e2.27\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum potassium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e4.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e0.71\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eBlood urea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e100.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e37.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum sodium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e137.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum calcium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e8.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum phosphate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e4.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSerum Albumin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eHemoglobin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e9.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e1.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eSBP during Headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e163.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e23.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 50%;\"\u003e\n \u003cp\u003eDBP during headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.4898%;\"\u003e\n \u003cp\u003e85.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.5102%;\"\u003e\n \u003cp\u003e11.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 2: Distribution according to gender and comorbidities\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eColumn N %\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 29px;\"\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e40.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e59.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 29px;\"\u003e\n \u003cp\u003eHypertension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e99.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 29px;\"\u003e\n \u003cp\u003eDiabetes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e47.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e52.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 29px;\"\u003e\n \u003cp\u003eOther co-morbidities\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eCoronary artery disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e10.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eHypothyroidism\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e10.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 34px;\"\u003e\n \u003cp\u003eNone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e78.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eAmong 102 patients, 40.2% were female and 59.8% were male, with marginal male preponderance in the study. The hypertension was present in 99% of cases, diabetes in 52.9% and other comorbidities were present in 21.6% of cases.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 3: Showing the variables details\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003eCount\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eN %\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eDialysis characteristics\u003c/p\u003e\n \u003cp\u003eFrequency of HD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eWeekly once\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eOnce every 5 days\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eTwice a week\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e34.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003ethrice a week\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e63.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eDialyzer reuse\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFirst use\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e68.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eRe use\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e31.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003ePresence of headache before starting dialysis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e76.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e23.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eHeadache associated with first dialysis session\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eMaybe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e6.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e64.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e28.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eSite of headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFrontal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e25.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFronto-parietal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e11.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFrontotemporal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e18.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eOccipital\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e7.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eParietal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\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: 24px;\"\u003e\n \u003cp\u003eTemporal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e32.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"6\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eTime between start of HD and onset of headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFirst 1 hour\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e4.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFirst 30 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e26.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eFirst 30min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eLast 1 hour\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e60.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eLast 30 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003ePost dialysis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e5.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"9\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eSeverity of headache: scale of 1 to 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e7.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e21.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e21.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e19.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e5.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e12.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e8.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003eTreatment of current headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eParacetamol\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e90.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eTramadol\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e9.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003ePast history of headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e73.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e26.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003ePast headache characteristic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eCluster headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eMigraine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e2.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eNot applicable\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e70.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eTension headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e25.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;Among the 102 patients undergoing hemodialysis (HD), the majority (63.7%) received dialysis thrice a week, followed by 34.3% who underwent it twice weekly. Most patients (68.6%) used a fresh dialyser, while 31.4% reused theirs. Headache before starting dialysis was reported by 23.5% of patients. During the first dialysis session, 28.4% experienced headaches, while 64.7% did not. The most common headache site was the temporal region (32.4%), followed by frontal (25.5%) and frontotemporal (18.6%) areas. Most headaches began in the last hour of dialysis (60.8%), with 26.5% occurring in the first 30 minutes. Headache severity varied, with the most frequently reported scores being 4 and 5 (each 21.6%), and a small proportion reporting extreme severity (score of 10: 1%). Paracetamol was the most commonly used treatment (90.2%), while 9.8% used tramadol. A history of headache was noted in 26.5% of patients, predominantly tension-type headaches (25.5%), with a few cases of migraine (2.9%) and cluster headaches (1.0%).\u003c/p\u003e\n\u003cp\u003eTable 4: Association of headache severity with blood pressure\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCorrelations\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003eHeadache (severity scale)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003ePre HD SBP\u0026quot;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.122\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.222\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003ePost HD SBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.071\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.480\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eSBP during Headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.202\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.042\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003ePre HD DBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e-0.084\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.401\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003ePost HD DBP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e-0.071\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.479\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eDBP during headache\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e-0.074\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.459\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eSerum potassium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e-0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.991\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eSerum sodium\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e-0.105\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24px;\"\u003e\n \u003cp\u003e0.295\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe correlation analysis between headache severity (on a scale) and various hemodynamic and biochemical parameters showed that systolic blood pressure (SBP) during the headache had a statistically significant positive correlation with headache severity (r = 0.202, *p = 0.042), suggesting that higher SBP during a headache episode may be associated with more severe headache. However, no significant correlations were found between headache severity and pre- or post-hemodialysis SBP, diastolic blood pressure (DBP) at any point, or serum levels of potassium and sodium, as all respective p-values were \u0026gt; 0.05.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eHeadache is a frequently reported complication during haemodialysis, affecting up to 70% of patients, with 28\u0026ndash;73% experiencing dialysis-specific headaches. Despite its high prevalence, the exact pathophysiology remains poorly understood. Contributing factors include the use of acetate-based dialysate, rapid shifts in blood pressure, and fluctuations in serum urea, sodium, and magnesium levels. Other possible triggers include caffeine withdrawal, hypoxemia, hard water syndrome (elevated calcium/magnesium in dialysate), and exposure to dialysate contaminants like fluoride or chloramine. Neurochemical changes\u0026mdash;such as altered levels of CGRP, substance P, and serotonin\u0026mdash;and osmotic shifts across the blood-brain barrier leading to cerebral oedema may also play key roles.\u003c/p\u003e\u003cp\u003e The present study included a total of 102 patients fulfilling the inclusion criteria with a mean age of 53.4\u0026thinsp;\u0026plusmn;\u0026thinsp;13.5yrs years. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the mean characteristics of blood pressure, electrolyte levels, and renal profile parameters among patients. 40.2% were female and 59.8% were male, with a marginal male preponderance in the study. The hypertension was present in 99% of cases, diabetes in 52.9% and other comorbidities were present in 21.6% of cases. In a similar study by Sousa M et al., with mean age was 51.8 years (\u0026plusmn;\u0026thinsp;13.6); 50% were women; 53% were married(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Also, in a study by Caplin et al., 54 per cent of the cohort were male, median age of 64 years.(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eAmong 102 hemodialysis patients, most (63.7%) underwent dialysis thrice weekly, and 68.6% used a fresh dialyser. Headaches were reported by 23.5% before dialysis and by 28.4% during the first session, with the temporal region being the most common site (32.4%). Headaches mostly began in the last hour of dialysis (60.8%) and were commonly rated at moderate severity (scores 4 and 5, each 21.6%). Paracetamol was the primary treatment (90.2%). A past headache history was seen in 26.5%, mainly tension-type headaches (25.5%). In a study by Sousa et al., 76 patients with primary headaches: 25 with migraine and 51 with tension-type headache. Anxiety was present in 28% and depression in 25%.(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eIn a study by Caplin et al., Fatigue was the most commonly reported symptom among patients undergoing dialysis, affecting 82% of them, followed by intradialytic hypotension (76%), muscle cramps (74%), and dizziness (63%). Other frequently experienced symptoms included headache (54%), pruritus (52%), and backache (51%). Fatigue occurred in approximately 50% of dialysis sessions, while hypotension and cramps were present in about 30% of sessions. In terms of post-dialysis recovery, 23% of patients felt better within minutes, 34% recovered by the time they reached home, 16% by bedtime, 24% by the following morning, and 3% only regained their usual state just before the next dialysis session.(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eThe correlation analysis between headache severity (on a scale) and various hemodynamic and biochemical parameters showed that systolic blood pressure (SBP) during the headache had a statistically significant positive correlation with headache severity (r\u0026thinsp;=\u0026thinsp;0.202, *p\u0026thinsp;=\u0026thinsp;0.042), suggesting that higher SBP during a headache episode may be associated with more severe headache. However, no significant correlations were found between headache severity and pre- or post-hemodialysis SBP, diastolic blood pressure (DBP) at any point, or serum levels of potassium and sodium, as all respective p-values were \u0026gt;\u0026thinsp;0.05.\u003c/p\u003e\u003cp\u003eIn a similar study by Goksan B et al., the most common location of headache pain was fronto-temporal, reported by 50% of patients, followed by occipital pain in 27% and diffuse pain in 23%. The majority of patients (87%) described the headache as throbbing in nature, while the remaining 13% experienced a dull type of pain. Regarding intensity, 73% of the headaches were of moderate severity and 27% were severe. In terms of duration, 63% of patients reported that their headaches lasted less than 4 hours, while 37% experienced headaches lasting between 4 and 24 hours. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) Among patients with haemodialysis headache (HDH), 41.67% (n\u0026thinsp;=\u0026thinsp;20; P\u0026thinsp;=\u0026thinsp;0.003) had a pre-existing headache disorder before starting dialysis, while the majority (58.33%) developed HDH de novo after beginning treatment. The average severity of pain, measured using the Visual Analogue Scale (VAS), was 4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.74, with a median score of 4.5 (interquartile range: 3\u0026ndash;7). Patients who experienced HDH had a higher mean score of 7.56\u0026thinsp;\u0026plusmn;\u0026thinsp;4.51 on the Patient Health Questionnaire-9 (PHQ-9), indicating greater depressive symptoms, compared to a mean score of 2.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.63 among those without dialysis-related headaches in a study by Chhaya K et al. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study aimed to assess the frequency and clinical characteristics of dialysis headache (DH) in patients undergoing haemodialysis, along with its associations with blood pressure and serum electrolytes. Among the 102 patients included, the prevalence of dialysis headache was 28.4% during the first dialysis session, with most headaches occurring in the last hour of dialysis and commonly affecting the temporal, frontal, and frontotemporal regions. The majority of headaches were of moderate severity, and paracetamol was the primary treatment used. A history of headache was seen in over a quarter of patients, mostly tension-type.\u003c/p\u003e\n\u003cp\u003eA statistically significant positive correlation was found between systolic blood pressure (SBP) during the headache and headache severity (r = 0.202, p = 0.042), indicating that elevated SBP may contribute to more intense headache episodes during dialysis. However, no significant associations were observed between dialysis headache and pre- or post-dialysis SBP, diastolic blood pressure, or serum levels of sodium and potassium. These findings suggest that intradialytic hemodynamic fluctuations, particularly elevated SBP during episodes, may play a key role in the pathophysiology of dialysis headache, while electrolyte levels appear less influential. Overall, the study underscores the importance of monitoring intradialytic blood pressure to better understand and manage DH in haemodialysis patients.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eHD: Haemodialysis\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;SBP: Systolic Blood Pressure\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; DBP: Diastolic Blood Pressure\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eWritten informed consent was obtained for anonymised patient information to be published in this article. The study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the institutional ethics committee of Narayana Medical College: IEC/NMC/16\u003csup\u003eth\u003c/sup\u003e May 2025/16.\u003c/p\u003e\n\u003cp\u003eConsent for publication was obtained from all participants after ensuring anonymity.\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials: Not applicable.\u003c/p\u003e\n\u003cp\u003eFunding: Nil\u003c/p\u003e\n\u003cp\u003eConflict of interest: Nil\u003c/p\u003e\n\u003cp\u003eAuthors\u0026rsquo; contributions:\u0026nbsp;\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003eA Sunnesh Reddy: conceptualisation, study design and data analysis and manuscript drafting and final approval of manuscript.\u003c/li\u003e\n \u003cli\u003eAnnadata Kumar Chakravarthy: Data collection, review and editing of manuscript.\u003c/li\u003e\n \u003cli\u003eBindu Menon: Data collection, manuscript drafting, critical review and editing and final approval of manuscript.\u003c/li\u003e\n \u003cli\u003eNamesh Kamat: Study design, data collection, data analysis and interpretation, manuscript drafting and final approval of manuscript.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eAcknowledgement: None.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eSousa Melo E, Carrilho Aguiar F, Sampaio Rocha-Filho PA. Dialysis Headache: A Narrative Review. Headache. 2017 Jan;57(1):161\u0026ndash;4.\u003c/li\u003e\n \u003cli\u003eSousa Melo E, Pedrosa RP, Carrilho Aguiar F, Valente LM, Sampaio Rocha-Filho PA. Dialysis headache: characteristics, impact and cerebrovascular evaluation. Arquivos de neuro-psiquiatria. 2022 Feb;80(2):129\u0026ndash;36.\u003c/li\u003e\n \u003cli\u003eAntoniazzi AL, Bigal ME, Bordini CA, Speciali JG. Headache associated with dialysis: the International Headache Society criteria revisited. Cephalalgia : an international journal of headache. 2003 Mar;23(2):146\u0026ndash;9.\u003c/li\u003e\n \u003cli\u003eGoksel BK, Torun D, Karaca S, Karatas M, Tan M, Sezgin N, et al. Is low blood magnesium level associated with hemodialysis headache? Headache. 2006 Jan;46(1):40\u0026ndash;5.\u003c/li\u003e\n \u003cli\u003eG\u0026ouml;ksan B, Karaali-Savrun F, Ertan S, Savrun M. Haemodialysis-related headache. Cephalalgia : an international journal of headache. 2004 Apr;24(4):284\u0026ndash;7.\u003c/li\u003e\n \u003cli\u003eGozubatik-Celik G, Uluduz D, Goksan B, Akkaya N, Sohtaoglu M, Uygunoglu U, et al. Hemodialysis-related headache and how to prevent it. European journal of neurology. 2019;26(1):100\u0026ndash;5.\u003c/li\u003e\n \u003cli\u003eBana DS, Yap AU, Graham JR. Headache during hemodialysis. Headache. 1972 Apr;12(1):1\u0026ndash;14.\u003c/li\u003e\n \u003cli\u003eAlessandri M, Massanti L, Geppetti P, Bellucci G, Cipriani M, Fanciullacci M. Plasma changes of calcitonin gene-related peptide and substance P in patients with dialysis headache. Cephalalgia : an international journal of headache. 2006 Nov;26(11):1287\u0026ndash;93.\u003c/li\u003e\n \u003cli\u003eZepeda-Orozco D, Quigley R. Dialysis disequilibrium syndrome. Pediatric nephrology (Berlin, Germany). 2012 Dec;27(12):2205\u0026ndash;11.\u003c/li\u003e\n \u003cli\u003eLeonard H, Pile T. Hard water syndrome: a case series of 30 patients from a London haemodialysis unit. Clinical kidney journal. 2020 Feb;13(1):111\u0026ndash;2.\u003c/li\u003e\n \u003cli\u003eCaplin B, Kumar S, Davenport A. Patients\u0026rsquo; perspective of haemodialysis-associated symptoms. Nephrology Dialysis Transplantation. 2011;26(8):2656\u0026ndash;63.\u003c/li\u003e\n \u003cli\u003eChhaya KT, Mankad S, Shah MK, Patel M, Desai D, Desai SD. Headache associated with hemodialysis in patients with end-stage renal disease in India: A common yet overlooked comorbidity. Annals of Indian Academy of Neurology. 2022;25(1):82\u0026ndash;7.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Dialysis headache, hemodialysis, blood pressure, serum electrolytes, intradialytic symptoms, headache severity","lastPublishedDoi":"10.21203/rs.3.rs-7454831/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7454831/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e\u003cp\u003eHeadache is a frequently reported symptom among hemodialysis (HD) patients, with 28\u0026ndash;73% experiencing dialysis-related headaches (DH). Despite its high prevalence, DH remains under-recognised and poorly understood. Various factors such as changes in blood pressure, electrolyte imbalances, and dialysate composition have been implicated in its pathophysiology. The present study aimed to assess the frequency and clinical characteristics of dialysis headache in HD patients.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMaterials \u0026amp; Methods\u003c/b\u003e\u003c/p\u003e\u003cp\u003eA prospective observational study was conducted on 102 HD patients at a tertiary care centre in South India. Patient data were collected using a standardised questionnaire based on ICHD criteria. Blood samples were drawn pre-heparinization for biochemical analysis. Headache characteristics were documented, and statistical analyses were conducted using t-tests, chi-square, and correlation methods, with p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 considered significant.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe mean age was 53.4\u0026thinsp;\u0026plusmn;\u0026thinsp;13.5 years; 59.8% were male. Most patients (63.7%) underwent dialysis thrice weekly. Headache was reported by 28.4% during dialysis, commonly in the temporal region and mostly in the final hour of treatment. The most frequent headache severity scores were 4 and 5. Systolic blood pressure during headache episodes showed a significant positive correlation with headache severity (r\u0026thinsp;=\u0026thinsp;0.202, p\u0026thinsp;=\u0026thinsp;0.042). No significant associations were found with serum sodium, potassium, or DBP.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e\u003cp\u003eDialysis headache is common and often correlates with elevated intradialytic SBP. Monitoring and managing intradialytic hemodynamics may help alleviate DH.\u003c/p\u003e","manuscriptTitle":"Headaches During Hemodialysis: A Neglected Yet Prevalent Syndrome","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-29 08:21:46","doi":"10.21203/rs.3.rs-7454831/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"77eb74c7-5459-4bcf-a26c-11bf1b3b0d99","owner":[],"postedDate":"September 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-22T07:53:34+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-29 08:21:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7454831","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7454831","identity":"rs-7454831","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}