Southern Buenos Aires stroke project

Background-Ethnic differences and vascular risk factors are the major deter minants of stroke subtypes. Nevertheless, specific data from undeveloped co untries is difficult to obtain. Natives from South America may have a highe r frequency of penetrating small vessel disease and hemorrhagic stroke. How ever, there are few studies in South America supporting these findings. Obj ective-We analyze demographic, ethnic, risk factors, clinical characteristi cs, and stroke subtypes in all patients,with acute stroke admitted to our h ospital. Methods-We studied all consecutive acute stroke patients admitted to the Ramos Mejia Hospital in Buenos Aires from 1997 to 1999. Our hospital serves a determined population of Southern Buenos Aires. Data were collect ed prospectively on patients' admission in a form especially designed for t his study including vascular risk factors, clinical features, epidemiologic al characteristics, and neuroradiological findings. Stroke subtypes were de termined according to the TOAST classification. Results-Among 361 acute str oke patients, 31% had hemorrhagic stroke. It was more frequent among Native s (34%) than Caucasians (27%) (P<0.002). Ischemic stroke subtypes were as f ollows: 105 (42%) patients had lacunar, 31 (12%) atherosclerotic stroke, 53 (21%) cardioembolic infarction, and 16 (6%) other causes of stroke. Forty- five (18%) patients were classified as undetermined. Small vessel disease w as higher among Caucasians (35%) than Natives (24%). Conclusions-Penetratin g artery disease (42%) and intracranial hemorrhage (31%) were the most comm on stroke subtypes, being more frequent than reported in the literature. Na tives had significantly higher frequency of hemorrhagic stroke than Caucasi ans.