Risk factors, etiology, and outcome of ischemic stroke in young adults: A Japanese multicenter prospective study.

Purpose: This study aimed to evaluate the risk factors, etiology, and outcomes of ischemic stroke (IS) in Japanese young adults.

Methods: This was a prospective multicenter study. We enrolled patients aged 16 to 55 years with IS within seven days of the onset of symptoms. We assessed the demographic data, risk factors, stroke etiology, and outcome at discharge. The clinical characteristics were compared between sexes and among age groups.

Results: We prospectively enrolled 519 patients (median age, 48 years: 139 females). The mean National Institute of Health Stroke Scale score was 3.6 ± 0.2. The most common risk factors were hypertension (HT) (55%), dyslipidemia (DL) (47%), and current smoking (42%). Body mass index, incidence of current smoking, and heavy alcohol consumption were higher in males. The prevalence of current smoking, HT, DL, and diabetes mellitus increased with aging. The most common etiologic subgroup of IS was small vessel disease (145/510, 28%). Intracranial arterial dissection (IAD) was the most common among the other determined causes (56/115, 49%). The outcome at discharge was relatively good (mRS 0-1, 71.7%); however, poor outcome (mRS ≥ 4) was observed at an incidence of 9.5%.

Conclusions: Most young adults with IS had modifiable risk factors, of which prevalence increased with age. This emphasizes lifestyle improvement to prevent IS in the young population. Furthermore, we indicated that the incidence rate of IAD was high among the other determined causes.