Background and PurposeThis study was designed to identify whether cigarette smoking, alcohol drinking, obesity, and use of oral contraceptives are independent risk factors for brain infarction among persons of working age.MethodsHealth habits and previous diseases of 506 patients (366 men and 140 women aged 16 to 60 years) with acute first-ever symptomatic brain infarction were compared with those of 345 hospitalized control patients (219 men and 126 women) who did not differ from case subjects in respect to day of onset of symptoms or acuteness of disease onset. With the use of stepwise logistic regression, the variables for which the simultaneous risks of acute brain infarction were tested by sex were age, amount of alcohol consumed within 24 hours and 1 week before the illness, heavy drinking, smoking status, current smoking, cardiac disease, hypertension, diabetes, hyperlipemia, migraine, body mass index, and, in women, current use of oral contraceptives.Results40 g ethanol within the 24 hours preceding the onset of illness increased the risk for acute brain infarction both among men (P<.001) and women (P<.01) independently from other risk factors. Other significant independent risk factors for brain infarction among men were hypertension (P<.001), cardiac disease (P<.01), current smoking (P<.01), diabetes (P<.05), and history of migraine (P<.05) and among women, current use of oral contraceptives (P<.01) and current smoking (P<.05).ConclusionsRecent heavy drinking of alcohol, hypertension, cardiac disease, current smoking, diabetes, and history of migraine among men, and recent heavy drinking of alcohol, current use of oral contraceptives, and current smoking among women, seem to be independent risk factors for acute brain infarction. (Stroke. 1997;28:26-30.)