Clinical characteristics of ischemic stroke in Japanese young adults.

Background and Purpose There is limited data on the characteristics of stroke in young adults in East Asia including Japan. We aimed to clarify the clinical characteristics of ischemic stroke in Japanese young adults. Methods We prospectively enrolled ischemic stroke patients aged 18 to 50 years old who were admitted to 5 high-volume stroke centers within 14 days after onset between February 2018 and January 2023. We collected clinical and imaging data based on the study protocol and analyzed them for conventional and specific stroke risk factors, stroke etiology, and clinical outcome. Results We enrolled 275 subjects (median age, 46 years; men, 71%; full time workers, 75%; median NIHSS score at admission, 2 points). The major risk factors were dyslipidemia (59%), hypertension (49%), and smoking (32%). Hyperhomocysteinemia, migraine, and antiphospholipid syndrome were found in 21%, 11% and 5%, respectively. The RNF213 p.R4810K variant was identified in 4.5%. The most common stroke etiologies were small vessel occlusion (26%) and arterial dissection (25%; intracranial in 20% and extracranial in 5%). The stroke recurrence rate was 5% at 3 months. Modified Rankin scale 0-1 at 3 months was observed in 76%, whereas 61% were able to return to their previous full-time work and 31% exhibited symptoms of depression. Conclusions The leading stroke etiologies in young adults in Japan were small vessel occlusion and intracranial arterial dissection, which differs from those observed in Western countries. Most young stroke patients had a favorable outcome, but some of them encountered problems relating to employment or mental health after their stroke.