Stroke subtype predicts outcome in young and middle-aged stroke sufferers

Objectives There are few studies on long-term outcome after ischemic stroke (IS) for young and middle-aged stroke sufferers in relation to etiologic subtypes. Here, we report 2-year outcome in the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS). Materials and methods SAHLSIS comprises 600 patients with IS before the age of 70 years. Etiologic subtype of IS was classified according to Trial of Org 10172 in Acute Stroke Treatment (TOAST). Recurrent vascular events and death were registered using several overlapping methods. Functional outcome was assessed according to the modified Rankin Scale (mRS). Results After 2 years, 55 (9.2%) patients had suffered a recurrent stroke, 15 (2.5%) had a transient ischemic attack (TIA), 4 (0.7%) had a coronary event, and 24 (4.0%) had died. The number of recurrent stroke, TIA, and death differed significantly between etiologic stroke subtypes. The highest rates were observed in large-vessel disease (LVD), whereas small-vessel disease and cryptogenic stroke showed the lowest recurrence and mortality rates. LVD was a significant predictor of the composite outcome (recurrent stroke, TIA, coronary event and/or death) independently of cardiovascular risk factors and stroke severity. Stroke subtype also predicted functional outcome 2 years after index stroke, but this association was not retained after adjustment for stroke severity. Conclusions In young and middle-aged stroke patients, stroke subtype predicts recurrent vascular events and/or death 2 years after index stroke independently of cardiovascular risk factors and stroke severity. Thus, it is important to take the etiologic subtype of IS in account when assessing the risk of recurrence both in the clinical setting and in future studies.