Moderate alcohol consumption and stroke. The epidemiologic evidence.

An extensive search of the English-language literature identified 62 epidemiologic studies that examined the relation between moderate alcohol consumption and risk of stroke. Moderate drinking (less than 60 g ethanol/day) and ischemic stroke have a complex association that might be explained by interaction with race; a J-shaped association has been found in predominantly white populations, while little (if any) association has been found among Japanese. By contrast, moderate drinking increases risk of both intracerebral and subarachnoid hemorrhage in diverse populations. There is insufficient epidemiologic evidence to conclude whether recent alcohol use affects risk of either ischemic or hemorrhagic stroke. These distinctive associations help explain contradictory reports on the relation between moderate alcohol consumption and risk of "stroke." The high prevalence of alcohol use throughout the world suggests opportunities for primary prevention and the importance of continued research in this area.