Multiple brain infarcts in young adults: clues for etiologic diagnosis and prognostic impact.

BACKGROUND AND PURPOSE There are little data on the etiology of multiple brain infarcts (MBI) and their impact on clinical outcome in young patients. METHODS We studied 548 MRI-imaged patients (15-49 years) with a first-ever ischaemic stroke. Ischaemic lesions were categorized into three groups: single lesions, MBI in one or >1 circulation territories. Outcomes were unfavorable 3-month modified Rankin Scale (mRS) score of ≥ 2 and, during long-term follow-up (mean 8.20 ± 4.01 years), recurrent ischaemic stroke or death from any cause. RESULTS Multiple brain infarcts occurred in 185 patients (33.8%; mean age 39.2 ± 8.2), of which 144 patients (26.3%) had lesions located in a single territory and 41 patients (7.5%) in multiple territories. Patients with MBI in a single territory were more likely than patients with single lesions to have a high-risk source of cardioembolism (CE) (9.0% vs. 3.0%; P = 0.001), large-artery atherosclerosis (8.3% vs. 4.9%; P = 0.012), vertebral (22% vs. 10%; P < 0.001) or carotid artery dissections (8.3% vs. 6.3%; P = 0.036), and MBI in multiple territories a high-risk source of CE (34% vs. 3.0%, P < 0.001). Adjusted for age, gender, baseline stroke severity, size of the largest lesion, and stroke subtype, MBI remained independently associated with an unfavorable 3-month outcome (odds ratio 2.84, 95% confidence interval 1.22-6.61). In multivariate Cox proportional hazards analysis, MBI had independent influence on the risk for death (hazard ratio 3.75, 1.58-8.86), but not on recurrent ischaemic stroke. CONCLUSIONS Compared with the elderly, young stroke patients have a distinct stroke etiology underlying MBI, being an independent indicator of poor short-term outcome and long-term risk of death.