Aetiological Features of ≥50 Years Old Patients with Newly Diagnosed Epilepsy in Eastern China

Aetiological Features of ≥50 Years Old Patients with Newly Diagnosed Epilepsy in Eastern China | 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 Aetiological Features of ≥50 Years Old Patients with Newly Diagnosed Epilepsy in Eastern China Changfeng Chai, Hongyan Chen, Xiaoying Bi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8698188/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 Purpose: The incidences of epilepsy in people aged 50 and above were at least twice than those in young people. Identifying the under cause is of great importance.In the present study, we summarized the aetiologic features aged ≥50 years old patients with newly diagnosed epilepsy in eastern China. Methods : We prospectively enrolled people older than 50 years with newly diagnosed epilepsy who were admitted in our hospital between January 2023 to October 2025. Demographic data, clinical characteristics,ASMs treatment, epilepsy-associated risk factors and medical history, and results of supplementary examinations of each participant were collected retrospectively via an interviewer-administered questionnaire and confirmed by the medical records. Results :Among 201 people enrolled , 64.18% of them were male. Aged 60 and above were more common, followed by those aged between 50 and 60, between 70 and 80 being the least. Cerebrovascular disease was the leading putative cause (40.80%) ,followed by unknown causes(20.90%).13 had remote traumatic brain injury(6.47%) ,which was the lowest proportion. Primary intracranial brain tumors and central nervous system(CNS) infections accounted for the same proportion. Among cerebrovascular disease, ischemic stroke was the leading cause,especially aged 60 and above. But in patients aged 50 to 60, ischemic stroke and intracranial vascular malformations (IVMs) were all the leading causes, arteriovenous malformations (AVMs) were the most common in IVMs.However, in female patients, IVMs appeared to account for a higher proportion of causes among those aged 50 to 60. Significance :In ≥50 years old patients with newly diagnosed epilepsy,stroke,especially ischemic stroke was the leading putative cause,especially aged 60 and above. But for young women, epilepsy caused by cerebrovascular malformations couldnot be ignored. Introduction Study had indicated that the incidences of epilepsy in people aged 50 and above were at least twice than those in young people. As the global population ages, the incidence of stroke and neurodegenerative diseases will increase. Therefore, the incidence of epilepsy will also increase due to the influence of multiple factors.According to literature, stroke is the third leading cause of death in developed countries and up to 65% of elderly people with new-onset epilepsy have evidence of prior cerebrovascular disease, more than five fold higher prevalence compared with age-matched individuals[ 1 ].In 2017, the Commission of the International League Against Epilepsy (ILAE) incorporated aetiology into its new classification for the first time, emphasizing the necessity of considering aetiology in each step of diagnosis. With the development of neuroimaging and electroencephalography (EEG) technologies, the aetiologies could be identified in most elderly epilepsy patients. The confirmation of brain damage or metabolic abnormalities causing epilepsy could be achieved through imaging examinations. However, due to factors such as age-related decline in physiological functions and the presence of multiple comorbidities in the elderly, the classification of epileptic seizures in these population was often atypical, as this had been demonstrated by an average delay of 1.7 years from the time of symptom onset to a formal diagnosis[ 2 ].Consequently, integrating the patient's etiologies may enhance the diagnostic rate and prognosis evaluation. By integrating clinical research data from the past two years, we analyzed the aetiological distribution of epilepsy in ≥ 50 years old, aiming to provide references for clinical practice. Materials and methods 2.1. Study design We conducted a prospective study in the eastern region of China between January 2023 and October 2025 in our hospital. People with epilepsy who came to visit the Epilepsy Outpatient Clinic and were admitted to hospital were prospectively. Inclusion criteria were reviewed by the interviewer. Eligible participants were: (1) Consecutive patients who were diagnosed of epilepsy after age of 50 or above and untreated before were included; (2) had been diagnosed epilepsy by the neurologists of our hospital; (3) were residents in Shanghai,Jiangsu (about 300 km away) Province, Zhejiang (about 200 kmaway) Province in China. Epilepsy is defined as at least two unprovoked seizures occurring more than 24h apart. Those with a single unprovoked seizure or acute symptomatic seizures were excluded [ 3 ]. The diagnosis was clinical and supplemented by EEG. 2.2. Clinical data collection Data collected included gender, age at admission, age at the seizure onset and disease duration. The demographic and clinical characteristics of the participants were retrospectively collected via an interviewer-administered questionnaire and confirmed by the medical records. Results of EEG and MRI/CT scans were reviewed and recorded. Local or generalized slow waves in the EEG recording were considered as non-specific abnormalities, while local or generalized paroxysms sharp waves,spike waves, sharp and slow waves, spike and slow waves were teemed as epileptiform discharges. The etiology of epilepsy was classified as genetic, structural, metabolic, immune, infectious or unknown [ 4 ]. 2.3. Ethics The study was approved by the Ethics Committees of Luodian Hospital, Shanghai,China. All participants provided informed consent. 2.4. Statistical analysis Continuous variables were reported as the median (range) or mean ± SD. Table 1 Characteristics of the study participants Age Male(N,Percent) Female(N,Percent) N,Percent 50∽60 43(33.33) 24(33.33) 67(33.33) 60∽70 57(44.19) 29(40.28) 86(42.79) 70∽80 29(22.48) 19(26.39) 48(23.88) 129(64.18) 72(35.82) 201 Table 2 Overall Aetiological Distribution Age cerebrovascular diseases (N,Percent) traumatic brain injury (N,Percent) Primary intracranial brain tumors(N,Percent) CNS infections(N,Percent) comorbidities from other medical disciplines(N,Percent) Unkown (N,Percent) 50∽60 29(43.28) 4(5.97) 13(19.40) 4(5.97) 7(10.45) 10(14.93) 60∽70 30(34.88) 5(5.81) 7(8.14) 16(18.60) 8(9.30) 20(23.26) 70∽80 23(47.92) 4(8.33) 4(8.33) 4(8.33) 1(2.08) 12(25.00) 82(40.80) 13(6.47) 24(11.94) 24(11.94) 16(7.96) 42(20.90) Table 3 Aetiological Distribution In Male Age cerebrovascular diseases (N,Percent) traumatic brain injury (N,Percent) Primary intracranial brain tumors(N,Percent) CNS infections(N,Percent) comorbidities from other medical disciplines(N,Percent) Unkown (N,Percent) 50∽60 21(48.84) 4(9.30) 9(20.93) 3(6.98) 2(4.65) 4(9.30) 60∽70 20(35.09) 3(5.26) 6(10.53) 13(22.81) 4(7.02) 11(19.30) 70∽80 9(31.03) 2(6.90) 3(10.34) 3(10.34) 1(3.45) 11(37.97) 50(38.76) 9(6.98) 18(13.95) 19(14.93) 7(5.43) 26(20.16) Table 4 Aetiological Distribution In Female Age cerebrovascular diseases (N,Percent) traumatic brain injury (N,Percent) Primary intracranial brain tumors(N,Percent) CNS infections(N,Percent) comorbidities from other medical disciplines(N,Percent) Unkown (N,Percent) 50∽60 8(33.33) 0 4(16.67) 1(4.17) 5(20.83) 6(25.00) 60∽70 10(34.48) 2(6.90) 1(3.45) 3(10.34) 4(13.79) 9(31.03) 70∽80 14(73.68) 2(10.53) 1(5.26) 1(5.26) 0 1(5.26) 32(44.44) 4(5.56) 6(8.33) 5(6.94) 9(12.50) 16(22.22) Table 5 Aetiology Distribution Classified As Cerebrovascular Disease Age ischemic stroke IVMs (N) CVT (N) SAH(N) early - onset late - onset 50∽60 6 6 12(AVMs:8,CCMs:1;Moyamoya disease 4) 4 1 29 60∽70 5 9 8(AVMs:6,CCMs:2) 0 8 30 70∽80 13 9 0 0 1 23 24 24 20 4 10 82 Table 6 Aetiology Distribution Classified As Cerebrovascular Disease In Male Age ischemic stroke IVMs (N) CVT (N) SAH(N) early - onset late - onset 50∽60 6 6 6(AVMs:4,CCMs:1;Moyamoya disease 1) 2 1 21 60∽70 3 9 7(AVMs:5,CCMs:2) 0 1 20 70∽80 5 4 0 0 0 9 14 19 13 2 2 50 Table 7 Aetiology Distribution Classified As Cerebrovascular Disease In Female Age ischemic stroke IVMs (N) CVT (N) SAH(N) early - onset late - onset 50∽60 0 0 6(AVMs:4, Moyamoya disease 2) 2 0 8 60∽70 2 0 1(AVMs:1) 0 7 10 70∽80 8 5 0 0 1 14 10 5 7 2 8 32 Results From January 2023 to October 2025, a total of 201 newly diagnosed epilepsy patients over 50 years old were enrolled in our study. All of these patients were mainly from eastern China (Shanghai, Jiangsu province, and Zhejiang province). As shown in Table 1 , 64.18%(129/201) were male.From an age distribution perspective, among newly diagnosed epilepsy patients, those aged 60 and above are the most common, followed by the 50–60, while the 70–80 had the lowest proportion. Table 2 showed aetiological features of elderly patients with newly diagnosed epilepsy .Among all aetiologies, structural had the largest proportion and cerebrovascular diseases were the most common, accounting 40.80% (82)of the total; followed by unknown causes, accounting for 20.90% (42). The lowest proportion was remote traumatic brain injury, accounting for 6.47% (13). Primary intracranial brain tumors and central nervous system(CNS) infections accounted for the same proportion in the overall aetiologies, but genetic and metabolic causes were not found. Table 3 showed among male patients aged 50–70, cerebrovascular diseases were the leading causes of newly diagnosed epilepsy. As age increased,the proportions of cases with unknown causes gradually rose, becoming the primary etiology in those aged 70 and above. Table 4 showed that, among female patients aged 50 and older, cerebrovascular diseases were the leading cause of newly diagnosed epilepsy, followed by unknown causes. Overall, among patients with newly diagnosed epilepsy caused by cerebrovascular disease, those approximately 58.54% were caused by ischemic stroke (Table 5 ). Both early and late post-stroke seizures were relatively common. Among patients aged 50 to 60 with newly diagnosed epilepsy, ischemic stroke and intracranial vascular malformations (IVMs) were all the leading causes, arteriovenous malformations (AVMs) were the most common.Among patients aged 60 and above, ischemic stroke was the leading cause of newly diagnosed epilepsy. The proportion of seizures caused by cerebral venous thrombosis(CVT) gradually decreased with age. When categorized by gender, ischemic stroke was the most common cause of newly diagnosed epilepsy in male patients(Table 6 ). However, among female patients aged 50 to 60,cerebrovascular malformations appeared to account for a higher proportion of cases (Table 7 ). These results indicated that female and relatively younger patients were at a higher risk of developing epilepsy due to arteriovenous malformations. This could lead us to speculate that if an unruptured intracranial AVM was found during routine imaging examinations in a young female patient, she may be at a higher risk for future epilepsy. Of the 201 patients, 30 underwent lumbar punctures and 24 were diagnosed with central nervous system (CNS) infections. These included viral encephalitis caused by various herpes viruses, including 10 cases of herpes simplex virus (HSV)-1, one case of HSV-2, and three cases of cytomegalovirus:14 cases; bacterial encephalitis/brain abscess: 4 cases, including 2 cases of neurosyphilis (both males); and autoimmune encephalitis: 4 cases of anti-LGI1 (three males and one female), one case of GAD 65 (female), and one case of GABAB (male). In this study, we found that some patients also experienced epileptic seizures due to primary intracranial brain tumors. Literature reports indicated that approximately 4% of patients with brain tumors experience epileptic seizures[ 5 ]. However, the risk of epilepsy varies depending on the type and characteristics of the tumor; the risk of epilepsy induced by low-grade gliomas is higher than that induced by high-grade gliomas [ 6 ]. In our study, we found that some patients experienced epileptic seizures due to comorbidities from other medical disciplines, such as systemic lupus erythematosus (SLE) and alcohol withdrawal. Discussion Despite advances in neuroimaging, the etiology of new-onset epilepsy in the elderly still remains unknown in approximately one-third to one-half of cases [ 7 – 8 ]. Accurately diagnosing epilepsy in the elderly is challenging, as challenges may arise from unreliable history-taking due to cognitive deficits and atypical seizure manifestations. Identifying etiologies plays a crucial role in diagnosing, assessing the prognosis assessment, and formulating a treatment plan for epileptic patients. Etiologies are also important for determining the risk of recurrence of epileptic seizures. A Norwegian study showed that epilepsy etiology was structural-metabolic in 43% of cases, genetic/presumed genetic in 20% of cases, and unknown in 32% of cases[ 9 ]. However, due to the potential influence of temporal and regional differences on the clinically observed etiological spectrum, studies conducted in China, even in eastern China, may yield inconsistent results with those from other countries. Our study, which included patients mainly from eastern China, indicated an increased incidence of epilepsy in elderly patients, particularly those aged 60 years and older. Stroke is the most common cause of epileptic seizures and epilepsy in this population. Post-stroke epilepsy (PSE) can be divided into early- and late-onset seizures. Late-onset epileptic seizures are associated with an increased risk of stroke recurrence and refer to epileptic seizures that occur within a certain period after a stroke. Recurrent epileptic seizures can cause damage and impair cognitive function and the ability to work or drive. Studies have demonstrated that subarachnoid hemorrhage is the most common type of stroke that leads to PSE. In our study, we also observed an increase in early-onset PSE caused by intracranial aneurysm rupture. However, this type of stroke was relatively uncommon in our research compared with other types. Among IVMs, AVMs and cerebral cavernous malformation (CCMs) are of particular significance in relation to epilepsy. Seizures caused by IVMs may be primary or secondary to intracerebral hemorrhage. In our study, all patients included underwent imaging examinations due to epileptic seizures. We also observed that, among IVMs, AVMs accounted for a relatively large proportion of etiologies in newly diagnosed epilepsy patients over 50 years old, particularly females. However, this trend was not observed in patients over 70 years of age. Based on our study, we hypothesized that young female patients may be more prone to developing epilepsy complicated by IVMs. Therefore, caution should be exercised when encountering such patients in clinical practice. Encephalitis is an inflammatory condition involving inflammation and swelling of the brain tissue, which is usually caused by viral infections. Herpes simplex virus type 1 (HSV-1) is the most common virus responsible for sporadic viral encephalitis[ 10 ]. Post-encephalitic epilepsy is a significant concern for survivors of (HSE). The occurrence of symptomatic epilepsy during the acute phase of HSE indicates a herpes simplex encephalitis n increased risk of epilepsy in the chronic phase [ 11 ] and predicts a poor long-term prognosis [ 12 ]. Autoimmune encephalitis (AE) typically has an acute or subacute onset and usually peaks within two to several weeks. It may be preceded by prodromal symptoms, such as fever and headache, and is primarily manifested by abnormal mental behavior. Studies have shown that approximately 75% of AE patients experience epileptic seizures, and refractory status epilepticus can lead to neuronal death[ 13 ]. Of the 201 patients in this study, 24 were ultimately diagnosed with epileptic seizures caused by CNS infections. Although this etiology was less common in elderly patients than in young patients, clinicians easily considered the possibility of encephalitis when encountering patients with acute encephalitis syndrome in clinical practice. It was recommended that, during a lumbar puncture, clinicians test for metagenomic next-generation sequencing and AE-related antibodies simultaneously to improve decision-making and medication use. Since etiology plays a core role in diagnosing and treating epilepsy, efforts to explore etiology should begin as soon as patients are admitted. For patients with epileptic seizures and a suspected structural etiology, for example, neuroimaging examinations should be performed (ideally using magnetic resonance imaging, if conditions permit). Our study supported previous research findings indicating that cerebrovascular disease was the primary cause of epileptic seizures in patients aged 60 years and older. Stroke accounted for the largest proportion of cerebrovascular diseases. However, among patients aged 50 to 60, especially newly diagnosed female epilepsy patients, the proportion of cerebrovascular malformations couldnot be ignored. Limitions The current study has several limitations. First, it is difficult to avoid selection bias in outpatient and hospital-based studies. Second, the number of patients over 80 years old in our study was relatively small, which was inconsistent with previous research. One possible reason for this discrepancy was that this group of patients was primarily managed in the emergency department because they were considered to have more severe conditions. In contrast, outpatient and inpatient conditions were generally milder than those in the emergency department. Third, few patients had experienced several seizure attacks before the age of 50. For reasons such as ignorance of symptoms, failure to seek medical help due to lack of medical knowledge, or misrecognition of the disease by local doctors, some patients were not diagnosed or treated before. Fourth, the use of an interviewer-administered questionnaire could not avoid recall bias, especially for information about early life risk factors. Conclusion Studies had indicated that new-onset epilepsy in the elderly most often presented as focal seizures[ 14 ], so determining the etiology of epilepsy was crucial for formulating treatment plans and management decisions for patients with epilepsy. This is also a key concern for patients with epilepsy themselves. Our study showed that stroke was the most common cause of epileptic seizures and epilepsy in elderly patients, especially those aged 60 and above. However, other causes, such as CNS infections and intracranial brain tumors, couldnot be overlooked. Rapid developments in fields such as genetics and neuroimaging have greatly advanced our understanding of the pathophysiology and etiology of epilepsy. As technology advances, our ability to identify etiologies will improve, and etiological classification systems will become more refined. In the future, there will be more studies on the etiology of epilepsy in elderly Chinese patients with larger sample sizes. We look forward to mapping the etiological spectrum of epilepsy patients. Abbreviations AE Autoimmune encephalitis AVM Arteriovenous malformations CCM Cerebral cavernous malformation CNS Central nervous system EEG Electroencephalography HSV-1 Herpes simplex virus type 1 HSE Herpes simplex encephalitis IVM Intracranial vascular malformation ILAE International League Against Epilepsy PSE Post-stroke epilepsy Declarations Acknowledgements We thank all the participants for their cooperation. Funding None. Conflicts of interest statement None of the authors has any conflict of interest to disclose. We confirm that we have read the Journal’s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines. Ethics approval and consent to participate This study was approved by the ethics committee of Shanghai Baoshan District Luodian Hospital(LDYY-KY-2026-04).Patients provided written consent for their anonymized medical date to be anylyzed and published for research purposes. Author Contribution Changfeng Chai and Hongyan Chen contributed equally to this workDate collection and curation:Changfeng ChaiDate analysis:Hongyan ChenManuscript drafting: Changfeng Chai,Hongyan Chen,Xiaoying BiManuscript revision: Xiaoying BiStudy design and supervising: Changfeng Chai,Xiaoying Bi References Martin R, Faught E, Richman J, Funkhouser E, Kim Y, Clements K, et al. Psychiatric and neurologic risk factors for incident cases of new-onset epilepsy in older adults:data from U.S. Medicare beneficiaries. Epilepsia 2014:1120–7. Hauser WA. Seizure disorders: the changes with age. Epilepsia 1992;33(Suppl. 4):S6–14. Thurman DJ, Beghi E, Begley CE, Berg AT, Buchhalter JR, Ding D, et al. Standards for epidemiologic studies and surveillance of epilepsy. Epilepsia 2011;52(Suppl. 7):2–26. Scheffer IE, French J, Hirsch E, Jain S, Mathern GW, Moshé SL, et al.Classification of the epilepsies: New concepts for discussion and debate-Special report of the ILAE Classification Task Force of the Commission for Classification and Terminology.Epilepsia Open 2016 Jul 21;1(1-2):37-44. Olafsson E, Ludvigsson P, Gudmundsson G, Hesdorffer D, Kjartansson O, Hauser WA. Incidence of unprovoked seizures and epilepsy in Iceland and assessment of the epilepsy syndrome classification: a prospective study. Lancet Neurol 2005;4:627–634. van Breemen MS, Wilms EB, Vecht CJ.Epilepsy in patients with brain tumours: epidemiology, mechanisms, and management. Lancet Neurol 2007;6:421–430. Rowan AJ, Ramsay RE, Collins JF, Pryor F, Boardman KD, Uthman BM, et al. New onset geriatric epilepsy: a randomized study of gabapentin, lamotrigine, and carbamazepine. Neurology 2005;64:1868–73. Pugh MJ, Knoefel JE, Mortensen EM, Amuan ME, Berlowitz DR, Van Cott AC. Newonset epilepsy risk factors in older veterans. J Am Geriatr Soc 2009;57:237–42. Syvertsen M, Nakken KO, Edland A, Hansen G, Hellum MK, Koht J. Prevalence and etiology of epilepsy in a Norwegian county: a population - based study. Epilepsia 2015; 56(5): 699 – 706 Granerod J, Ambrose HE, Davies NW, Clewley JP, Walsh AL, Morgan D, et al. Causes of encephalitis and differences in their clinical presentations in England: a multicentre, population-based prospective study. Lancet Infect Dis. 2010 Dec;10(12):835-44. Stahl JP, Mailles A, De Broucker T. Herpes simplex encephalitis and management of acyclovir in encephalitis patients in France. Epidemiol Infect 2012, 140(2): 372 – 381 Misra UK, Kalita J. Seizures in encephalitis: predictors and outcome. Seizure 2009, 18: 583 – 587 Geis C, Planagumà J, Carreño M,Graus F,Dalmau J. Autoimmune seizures and epilepsy. The Journal of Clinical Investigation 2019, 129(3): 926 – 940. Lezaic N, Roussy J, Masson H, Jetté N, Keezer MR.Epilepsy in the elderly: Unique challenges in an increasingly prevalent population.Epilepsy Behav 2020 Jan;102:106724. Additional Declarations No competing interests reported. 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. 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-8698188","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":582722128,"identity":"013e0dd2-e1c3-421d-b9c6-7a20060654f3","order_by":0,"name":"Changfeng Chai","email":"","orcid":"","institution":"Baoshan District Luodian Hospital","correspondingAuthor":false,"prefix":"","firstName":"Changfeng","middleName":"","lastName":"Chai","suffix":""},{"id":582722133,"identity":"5b6bffe6-c9c7-4489-916c-d8f2a36feb31","order_by":1,"name":"Hongyan Chen","email":"","orcid":"","institution":"Baoshan District Luodian Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hongyan","middleName":"","lastName":"Chen","suffix":""},{"id":582722137,"identity":"0cfe8fae-a1ff-466a-94ac-a2e859a86e9d","order_by":2,"name":"Xiaoying Bi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAy0lEQVRIiWNgGAWjYBAC+2b2479/8NjI8bM3EKnFgJ0nQZpBJs1YsucAsVr4GQykGWwOJxrcSCBSizkzQ4JxQU5aAsPNxxtvMNTYRBPUYtnMeCB5xhmbPMbZacUWDMfSchsI6jnMkHCAtyetmFk6x0yCseEwUVoMG3j/HU5skzxDpBaDwwzGzDw8hxN7JHiI1CLZzJPGOIMnzViCB+iXBGL8ws9//BjDB2BU2h8/vPHGhxobIvyC7EiJBFKUQ7SQqmMUjIJRMApGBgAAd6A8diFV1Z8AAAAASUVORK5CYII=","orcid":"","institution":"Institute of Neurology,The First Affliated Hospital of Naval Medical University (Second Military Medical University)","correspondingAuthor":true,"prefix":"","firstName":"Xiaoying","middleName":"","lastName":"Bi","suffix":""}],"badges":[],"createdAt":"2026-01-26 08:38:32","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8698188/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8698188/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102295616,"identity":"4431c9f6-b44e-40ee-9bbb-337e02b62827","added_by":"auto","created_at":"2026-02-10 10:13:11","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":870277,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8698188/v1/0fc4102e-cfb9-4535-a046-2a4b9cd9d0bd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Aetiological Features of ≥50 Years Old Patients with Newly Diagnosed Epilepsy in Eastern China","fulltext":[{"header":"Introduction","content":"\u003cp\u003eStudy had indicated that the incidences of epilepsy in people aged 50 and above were at least twice than those in young people. As the global population ages, the incidence of stroke and neurodegenerative diseases will increase. Therefore, the incidence of epilepsy will also increase due to the influence of multiple factors.According to literature, stroke is the third leading cause of death in developed countries and up to 65% of elderly people with new-onset epilepsy have evidence of prior cerebrovascular disease, more than five fold higher prevalence compared with age-matched individuals[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].In 2017, the Commission of the International League Against Epilepsy (ILAE) incorporated aetiology into its new classification for the first time, emphasizing the necessity of considering aetiology in each step of diagnosis.\u003c/p\u003e \u003cp\u003eWith the development of neuroimaging and electroencephalography (EEG) technologies, the aetiologies could be identified in most elderly epilepsy patients. The confirmation of brain damage or metabolic abnormalities causing epilepsy could be achieved through imaging examinations. However, due to factors such as age-related decline in physiological functions and the presence of multiple comorbidities in the elderly, the classification of epileptic seizures in these population was often atypical, as this had been demonstrated by an average delay of 1.7 years from the time of symptom onset to a formal diagnosis[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].Consequently, integrating the patient's etiologies may enhance the diagnostic rate and prognosis evaluation.\u003c/p\u003e \u003cp\u003eBy integrating clinical research data from the past two years, we analyzed the aetiological distribution of epilepsy in \u0026ge;\u0026thinsp;50 years old, aiming to provide references for clinical practice.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Study design\u003c/h2\u003e \u003cp\u003eWe conducted a prospective study in the eastern region of China between January 2023 and October 2025 in our hospital. People with epilepsy who came to visit the Epilepsy Outpatient Clinic and were admitted to hospital were prospectively. Inclusion criteria were reviewed by the interviewer. Eligible participants were: (1) Consecutive patients who were diagnosed of epilepsy after age of 50 or above and untreated before were included; (2) had been diagnosed epilepsy by the neurologists of our hospital; (3) were residents in Shanghai,Jiangsu (about 300 km away) Province, Zhejiang (about 200 kmaway) Province in China.\u003c/p\u003e \u003cp\u003eEpilepsy is defined as at least two unprovoked seizures occurring more than 24h apart. Those with a single unprovoked seizure or acute symptomatic seizures were excluded [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The diagnosis was clinical and supplemented by EEG.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Clinical data collection\u003c/h2\u003e \u003cp\u003eData collected included gender, age at admission, age at the seizure onset and disease duration.\u003c/p\u003e \u003cp\u003eThe demographic and clinical characteristics of the participants were retrospectively collected via an interviewer-administered questionnaire and confirmed by the medical records. Results of EEG and MRI/CT scans were reviewed and recorded. Local or generalized slow waves in the EEG recording were considered as non-specific abnormalities, while local or generalized paroxysms sharp waves,spike waves, sharp and slow waves, spike and slow waves were teemed as epileptiform discharges. The etiology of epilepsy was classified as genetic, structural, metabolic, immune, infectious or unknown [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Ethics\u003c/h2\u003e \u003cp\u003e The study was approved by the Ethics Committees of Luodian Hospital, Shanghai,China. All participants provided informed consent.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Statistical analysis\u003c/h2\u003e \u003cp\u003eContinuous variables were reported as the median (range) or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of the study participants\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFemale(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eN,Percent\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e43(33.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e24(33.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e67(33.33)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e57(44.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e29(40.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e86(42.79)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29(22.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19(26.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e48(23.88)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e129(64.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e72(35.82)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e201\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eOverall Aetiological Distribution\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ecerebrovascular diseases (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003etraumatic brain injury (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePrimary intracranial brain tumors(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCNS infections(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ecomorbidities from other medical disciplines(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnkown\u003c/p\u003e \u003cp\u003e(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29(43.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4(5.97)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e13(19.40)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4(5.97)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e7(10.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e10(14.93)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e30(34.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5(5.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7(8.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e16(18.60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8(9.30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e20(23.26)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e23(47.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4(8.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4(8.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4(8.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1(2.08)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e12(25.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e82(40.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e13(6.47)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e24(11.94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e24(11.94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e16(7.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e42(20.90)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAetiological Distribution In Male\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ecerebrovascular diseases (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003etraumatic brain injury (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePrimary intracranial brain tumors(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCNS infections(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ecomorbidities from other medical disciplines(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnkown\u003c/p\u003e \u003cp\u003e(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21(48.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4(9.30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e9(20.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3(6.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2(4.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e4(9.30)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e20(35.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3(5.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e6(10.53)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e13(22.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4(7.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e11(19.30)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9(31.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2(6.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3(10.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3(10.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1(3.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e11(37.97)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50(38.76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9(6.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e18(13.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e19(14.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e7(5.43)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e26(20.16)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAetiological Distribution In Female\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ecerebrovascular diseases (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003etraumatic brain injury (N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePrimary intracranial brain tumors(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCNS infections(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ecomorbidities from other medical disciplines(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnkown\u003c/p\u003e \u003cp\u003e(N,Percent)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8(33.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4(16.67)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1(4.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5(20.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e6(25.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10(34.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(6.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1(3.45)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3(10.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4(13.79)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e9(31.03)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14(73.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(10.53)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1(5.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1(5.26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1(5.26)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32(44.44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(5.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e6(8.33)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e5(6.94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9(12.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e16(22.22)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAetiology Distribution Classified As Cerebrovascular Disease\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eischemic stroke\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eIVMs (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCVT (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSAH(N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eearly - onset\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003elate - onset\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12(AVMs:8,CCMs:1;Moyamoya disease 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8(AVMs:6,CCMs:2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e82\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAetiology Distribution Classified As Cerebrovascular Disease In Male\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eischemic stroke\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eIVMs (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCVT (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSAH(N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eearly - onset\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003elate - onset\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6(AVMs:4,CCMs:1;Moyamoya disease 1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7(AVMs:5,CCMs:2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAetiology Distribution Classified As Cerebrovascular Disease In Female\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eischemic stroke\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eIVMs (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCVT (N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSAH(N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eearly - onset\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003elate - onset\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50∽60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6(AVMs:4, Moyamoya disease 2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e60∽70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1(AVMs:1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e70∽80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eFrom January 2023 to October 2025, a total of 201 newly diagnosed epilepsy patients over 50 years old were enrolled in our study. All of these patients were mainly from eastern China (Shanghai, Jiangsu province, and Zhejiang province).\u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, 64.18%(129/201) were male.From an age distribution perspective, among newly diagnosed epilepsy patients, those aged 60 and above are the most common, followed by the 50\u0026ndash;60, while the 70\u0026ndash;80 had the lowest proportion.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e showed aetiological features of elderly patients with newly diagnosed epilepsy .Among all aetiologies, structural had the largest proportion and cerebrovascular diseases were the most common, accounting 40.80% (82)of the total; followed by unknown causes, accounting for 20.90% (42). The lowest proportion was remote traumatic brain injury, accounting for 6.47% (13). Primary intracranial brain tumors and central nervous system(CNS) infections accounted for the same proportion in the overall aetiologies, but genetic and metabolic causes were not found.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e showed among male patients aged 50\u0026ndash;70, cerebrovascular diseases were the leading causes of newly diagnosed epilepsy. As age increased,the proportions of cases with unknown causes gradually rose, becoming the primary etiology in those aged 70 and above.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e showed that, among female patients aged 50 and older, cerebrovascular diseases were the leading cause of newly diagnosed epilepsy, followed by unknown causes.\u003c/p\u003e \u003cp\u003eOverall, among patients with newly diagnosed epilepsy caused by cerebrovascular disease, those approximately 58.54% were caused by ischemic stroke (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Both early and late post-stroke seizures were relatively common. Among patients aged 50 to 60 with newly diagnosed epilepsy, ischemic stroke and intracranial vascular malformations (IVMs) were all the leading causes, arteriovenous malformations (AVMs) were the most common.Among patients aged 60 and above, ischemic stroke was the leading cause of newly diagnosed epilepsy. The proportion of seizures caused by cerebral venous thrombosis(CVT) gradually decreased with age. When categorized by gender, ischemic stroke was the most common cause of newly diagnosed epilepsy in male patients(Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). However, among female patients aged 50 to 60,cerebrovascular malformations appeared to account for a higher proportion of cases (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). These results indicated that female and relatively younger patients were at a higher risk of developing epilepsy due to arteriovenous malformations. This could lead us to speculate that if an unruptured intracranial AVM was found during routine imaging examinations in a young female patient, she may be at a higher risk for future epilepsy.\u003c/p\u003e \u003cp\u003eOf the 201 patients, 30 underwent lumbar punctures and 24 were diagnosed with central nervous system (CNS) infections. These included viral encephalitis caused by various herpes viruses, including 10 cases of herpes simplex virus (HSV)-1, one case of HSV-2, and three cases of cytomegalovirus:14 cases; bacterial encephalitis/brain abscess: 4 cases, including 2 cases of neurosyphilis (both males); and autoimmune encephalitis: 4 cases of anti-LGI1 (three males and one female), one case of GAD 65 (female), and one case of GABAB (male).\u003c/p\u003e \u003cp\u003eIn this study, we found that some patients also experienced epileptic seizures due to primary intracranial brain tumors. Literature reports indicated that approximately 4% of patients with brain tumors experience epileptic seizures[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, the risk of epilepsy varies depending on the type and characteristics of the tumor; the risk of epilepsy induced by low-grade gliomas is higher than that induced by high-grade gliomas [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn our study, we found that some patients experienced epileptic seizures due to comorbidities from other medical disciplines, such as systemic lupus erythematosus (SLE) and alcohol withdrawal.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eDespite advances in neuroimaging, the etiology of new-onset epilepsy in the elderly still remains unknown in approximately one-third to one-half of cases [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Accurately diagnosing epilepsy in the elderly is challenging, as challenges may arise from unreliable history-taking due to cognitive deficits and atypical seizure manifestations. Identifying etiologies plays a crucial role in diagnosing, assessing the prognosis assessment, and formulating a treatment plan for epileptic patients. Etiologies are also important for determining the risk of recurrence of epileptic seizures. A Norwegian study showed that epilepsy etiology was structural-metabolic in 43% of cases, genetic/presumed genetic in 20% of cases, and unknown in 32% of cases[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, due to the potential influence of temporal and regional differences on the clinically observed etiological spectrum, studies conducted in China, even in eastern China, may yield inconsistent results with those from other countries.\u003c/p\u003e \u003cp\u003eOur study, which included patients mainly from eastern China, indicated an increased incidence of epilepsy in elderly patients, particularly those aged 60 years and older. Stroke is the most common cause of epileptic seizures and epilepsy in this population. Post-stroke epilepsy (PSE) can be divided into early- and late-onset seizures. Late-onset epileptic seizures are associated with an increased risk of stroke recurrence and refer to epileptic seizures that occur within a certain period after a stroke. Recurrent epileptic seizures can cause damage and impair cognitive function and the ability to work or drive. Studies have demonstrated that subarachnoid hemorrhage is the most common type of stroke that leads to PSE. In our study, we also observed an increase in early-onset PSE caused by intracranial aneurysm rupture. However, this type of stroke was relatively uncommon in our research compared with other types.\u003c/p\u003e \u003cp\u003eAmong IVMs, AVMs and cerebral cavernous malformation (CCMs) are of particular significance in relation to epilepsy. Seizures caused by IVMs may be primary or secondary to intracerebral hemorrhage. In our study, all patients included underwent imaging examinations due to epileptic seizures. We also observed that, among IVMs, AVMs accounted for a relatively large proportion of etiologies in newly diagnosed epilepsy patients over 50 years old, particularly females. However, this trend was not observed in patients over 70 years of age. Based on our study, we hypothesized that young female patients may be more prone to developing epilepsy complicated by IVMs. Therefore, caution should be exercised when encountering such patients in clinical practice.\u003c/p\u003e \u003cp\u003eEncephalitis is an inflammatory condition involving inflammation and swelling of the brain tissue, which is usually caused by viral infections. Herpes simplex virus type 1 (HSV-1) is the most common virus responsible for sporadic viral encephalitis[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Post-encephalitic epilepsy is a significant concern for survivors of (HSE). The occurrence of symptomatic epilepsy during the acute phase of HSE indicates a herpes simplex encephalitis n increased risk of epilepsy in the chronic phase [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] and predicts a poor long-term prognosis [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Autoimmune encephalitis (AE) typically has an acute or subacute onset and usually peaks within two to several weeks. It may be preceded by prodromal symptoms, such as fever and headache, and is primarily manifested by abnormal mental behavior. Studies have shown that approximately 75% of AE patients experience epileptic seizures, and refractory status epilepticus can lead to neuronal death[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Of the 201 patients in this study, 24 were ultimately diagnosed with epileptic seizures caused by CNS infections. Although this etiology was less common in elderly patients than in young patients, clinicians easily considered the possibility of encephalitis when encountering patients with acute encephalitis syndrome in clinical practice. It was recommended that, during a lumbar puncture, clinicians test for metagenomic next-generation sequencing and AE-related antibodies simultaneously to improve decision-making and medication use.\u003c/p\u003e \u003cp\u003eSince etiology plays a core role in diagnosing and treating epilepsy, efforts to explore etiology should begin as soon as patients are admitted. For patients with epileptic seizures and a suspected structural etiology, for example, neuroimaging examinations should be performed (ideally using magnetic resonance imaging, if conditions permit). Our study supported previous research findings indicating that cerebrovascular disease was the primary cause of epileptic seizures in patients aged 60 years and older. Stroke accounted for the largest proportion of cerebrovascular diseases. However, among patients aged 50 to 60, especially newly diagnosed female epilepsy patients, the proportion of cerebrovascular malformations couldnot be ignored.\u003c/p\u003e"},{"header":"Limitions","content":"\u003cp\u003eThe current study has several limitations. First, it is difficult to avoid selection bias in outpatient and hospital-based studies. Second, the number of patients over 80 years old in our study was relatively small, which was inconsistent with previous research. One possible reason for this discrepancy was that this group of patients was primarily managed in the emergency department because they were considered to have more severe conditions. In contrast, outpatient and inpatient conditions were generally milder than those in the emergency department.\u003c/p\u003e \u003cp\u003eThird, few patients had experienced several seizure attacks before the age of 50.\u003c/p\u003e \u003cp\u003eFor reasons such as ignorance of symptoms, failure to seek medical help due to lack of medical knowledge, or misrecognition of the disease by local doctors, some patients were not diagnosed or treated before. Fourth, the use of an interviewer-administered questionnaire could not avoid recall bias, especially for information about early life risk factors.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eStudies had indicated that new-onset epilepsy in the elderly most often presented as focal seizures[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], so determining the etiology of epilepsy was crucial for formulating treatment plans and management decisions for patients with epilepsy. This is also a key concern for patients with epilepsy themselves. Our study showed that stroke was the most common cause of epileptic seizures and epilepsy in elderly patients, especially those aged 60 and above. However, other causes, such as CNS infections and intracranial brain tumors, couldnot be overlooked. Rapid developments in fields such as genetics and neuroimaging have greatly advanced our understanding of the pathophysiology and etiology of epilepsy. As technology advances, our ability to identify etiologies will improve, and etiological classification systems will become more refined. In the future, there will be more studies on the etiology of epilepsy in elderly Chinese patients with larger sample sizes. We look forward to mapping the etiological spectrum of epilepsy patients.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eAE\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u003c/strong\u003eAutoimmune encephalitis\u003c/p\u003e\n\u003cp\u003eAVM \u0026nbsp; Arteriovenous malformations\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCCM \u0026nbsp; Cerebral cavernous malformation\u003c/p\u003e\n\u003cp\u003eCNS \u0026nbsp; Central nervous system\u003c/p\u003e\n\u003cp\u003eEEG \u0026nbsp;\u0026nbsp;Electroencephalography\u003c/p\u003e\n\u003cp\u003eHSV-1 Herpes simplex virus type 1\u003c/p\u003e\n\u003cp\u003eHSE \u0026nbsp;Herpes simplex encephalitis\u003c/p\u003e\n\u003cp\u003eIVM \u0026nbsp;Intracranial vascular malformation\u003c/p\u003e\n\u003cp\u003eILAE \u0026nbsp;International League Against Epilepsy\u003c/p\u003e\n\u003cp\u003ePSE \u0026nbsp;Post-stroke epilepsy\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAcknowledgements\u003c/h2\u003e\n\u003cp\u003eWe thank all the participants for their cooperation.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eNone.\u003c/p\u003e\n\u003ch2\u003eConflicts of interest statement\u003c/h2\u003e\n\u003cp\u003eNone of the authors has any conflict of interest to disclose. We confirm that we have read the Journal\u0026rsquo;s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.\u003c/p\u003e\n\u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e\n\u003cp\u003eThis study was approved by the ethics committee of Shanghai Baoshan District Luodian Hospital(LDYY-KY-2026-04).Patients provided written consent for their anonymized medical date to be anylyzed and published for research purposes.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eChangfeng Chai and Hongyan Chen contributed equally to this workDate collection and curation:Changfeng ChaiDate analysis:Hongyan ChenManuscript drafting: Changfeng Chai,Hongyan Chen,Xiaoying BiManuscript revision: Xiaoying BiStudy design and supervising: Changfeng Chai,Xiaoying Bi\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMartin R, Faught E, Richman J, Funkhouser E, Kim Y, Clements K, et al. Psychiatric and neurologic risk factors for incident cases of new-onset epilepsy in older adults:data from U.S. Medicare beneficiaries. Epilepsia 2014:1120\u0026ndash;7.\u003c/li\u003e\n\u003cli\u003eHauser WA. Seizure disorders: the changes with age. Epilepsia 1992;33(Suppl. 4):S6\u0026ndash;14.\u003c/li\u003e\n\u003cli\u003eThurman DJ, Beghi E, Begley CE, Berg AT, Buchhalter JR, Ding D, et al. Standards for epidemiologic studies and surveillance of epilepsy. Epilepsia 2011;52(Suppl. 7):2\u0026ndash;26.\u003c/li\u003e\n\u003cli\u003eScheffer IE, French J, Hirsch E, Jain S, Mathern GW, Mosh\u0026eacute; SL, et al.Classification of the epilepsies: New concepts for discussion and debate-Special report of the ILAE Classification Task Force of the Commission for Classification and Terminology.Epilepsia Open 2016 Jul 21;1(1-2):37-44.\u003c/li\u003e\n\u003cli\u003eOlafsson E, Ludvigsson P, Gudmundsson G, Hesdorffer D, Kjartansson O, Hauser WA. Incidence of unprovoked seizures and epilepsy in Iceland and assessment of the epilepsy syndrome classification: a prospective study. Lancet Neurol 2005;4:627\u0026ndash;634.\u003c/li\u003e\n\u003cli\u003evan Breemen MS, Wilms EB, Vecht CJ.Epilepsy in patients with brain tumours: epidemiology, mechanisms, and management. Lancet Neurol 2007;6:421\u0026ndash;430.\u003c/li\u003e\n\u003cli\u003eRowan AJ, Ramsay RE, Collins JF, Pryor F, Boardman KD, Uthman BM, et al. New onset geriatric epilepsy: a randomized study of gabapentin, lamotrigine, and carbamazepine. Neurology 2005;64:1868\u0026ndash;73.\u003c/li\u003e\n\u003cli\u003ePugh MJ, Knoefel JE, Mortensen EM, Amuan ME, Berlowitz DR, Van Cott AC. Newonset epilepsy risk factors in older veterans. J Am Geriatr Soc 2009;57:237\u0026ndash;42.\u003c/li\u003e\n\u003cli\u003eSyvertsen M, Nakken KO, Edland A, Hansen G, Hellum MK, Koht J. Prevalence and etiology of epilepsy in a Norwegian county: a population - based study. Epilepsia 2015; 56(5): 699 \u0026ndash; 706\u003c/li\u003e\n\u003cli\u003eGranerod J, Ambrose HE, Davies NW, Clewley JP, Walsh AL, Morgan D, et al. Causes of encephalitis and differences in their clinical presentations in England: a multicentre, population-based prospective study. Lancet Infect Dis. 2010 Dec;10(12):835-44. \u003c/li\u003e\n\u003cli\u003eStahl JP, Mailles A, De Broucker T. Herpes simplex encephalitis and management of acyclovir in encephalitis patients in France. Epidemiol Infect 2012, 140(2): 372 \u0026ndash; 381\u003c/li\u003e\n\u003cli\u003eMisra UK, Kalita J. Seizures in encephalitis: predictors and outcome. Seizure 2009, 18: 583 \u0026ndash; 587\u003c/li\u003e\n\u003cli\u003eGeis C, Planagum\u0026agrave; J, Carre\u0026ntilde;o M,Graus F,Dalmau J. Autoimmune seizures and epilepsy. The Journal of Clinical Investigation 2019, 129(3): 926 \u0026ndash; 940.\u003c/li\u003e\n\u003cli\u003eLezaic N, Roussy J, Masson H, Jett\u0026eacute; N, Keezer MR.Epilepsy in the elderly: Unique challenges in an increasingly prevalent population.Epilepsy Behav 2020 Jan;102:106724.\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":"","lastPublishedDoi":"10.21203/rs.3.rs-8698188/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8698188/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose:\u003c/strong\u003eThe incidences of epilepsy in people aged 50 and above were at least twice than those in young people. Identifying the under cause is of great importance.In the present study, we summarized the aetiologic features aged ≥50 years old patients with newly diagnosed epilepsy in eastern China.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e: We prospectively enrolled people older than 50 years with newly diagnosed epilepsy who were admitted in our hospital between January 2023 to October 2025. Demographic data, clinical characteristics,ASMs treatment, epilepsy-associated risk factors and medical history, and results of supplementary examinations of each participant were collected retrospectively via an interviewer-administered questionnaire and confirmed by the medical records.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e:Among 201 people enrolled , 64.18% of them were male. Aged 60 and above were more common, followed by those aged between 50 and 60, between 70 and 80 being the least. Cerebrovascular disease was the leading putative cause (40.80%) ,followed by unknown causes(20.90%).13 had remote traumatic brain injury(6.47%) ,which was the lowest proportion. Primary intracranial brain tumors and central nervous system(CNS) infections accounted for the same proportion. Among cerebrovascular disease, ischemic stroke was the leading cause,especially aged 60 and above. But in patients aged 50 to 60, ischemic stroke and intracranial vascular malformations (IVMs) were all the leading causes, arteriovenous malformations (AVMs) were the most common in IVMs.However, in female patients, IVMs appeared to account for a higher proportion of causes among those aged 50 to 60.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSignificance\u003c/strong\u003e:In ≥50 years old patients with newly diagnosed epilepsy,stroke,especially ischemic stroke was the leading putative cause,especially aged 60 and above. But for young women, epilepsy caused by cerebrovascular malformations couldnot be ignored.\u003c/p\u003e","manuscriptTitle":"Aetiological Features of ≥50 Years Old Patients with Newly Diagnosed Epilepsy in Eastern China","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-30 15:23:43","doi":"10.21203/rs.3.rs-8698188/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":"3e1819cb-73ed-4d20-8f94-8bfbec18052a","owner":[],"postedDate":"January 30th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-06T09:56:46+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-30 15:23:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8698188","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8698188","identity":"rs-8698188","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}