Background and purpose: Understanding the effects of alcohol intake on stroke and other cardiovascular diseases is an important issue for public health.
Methods: A 10.5-year prospective study of the relationship between alcohol intake and cardiovascular disease incidence was conducted in 2890 men, aged 40 to 69 years and free of a history of stroke and coronary heart disease, in three rural communities of Japan.
Results: One hundred seventy-eight strokes (40 intracerebral hemorrhages, 18 subarachnoid hemorrhages, 104 nonhemorrhagic strokes, and 16 unclassified strokes), 34 coronary heart disease events, and 19 sudden unclassified deaths occurred. Drinkers of > or = 70 g/d ethanol had an approximately 2.5 times higher age-adjusted risk of all stroke than never-drinkers; the excess risk was more evident for hemorrhagic stroke than nonhemorrhagic stroke. When hypertension category, serum total cholesterol level, cigarette smoking, and diabetes mellitus were taken into account, these excess risks were reduced but remained significant for all stroke (2.0; 95% confidence interval, 1.3 to 3.1) and hemorrhagic stroke (3.4; 95% confidence interval, 1.2 to 9.2). A J-shaped relationship was suggested between alcohol intake and risk of nonhemorrhagic stroke; drinkers of < 42 g/d ethanol had a slightly lower risk and heavy drinkers had a higher risk than never-drinkers. Current drinkers had a slightly lower risk of coronary heart disease than never-drinkers, although the risk difference was not statistically significant. The age-adjusted risk of sudden death was 10 times higher in heavy drinkers than never-drinkers, and the excess risk did not change when the covariates were controlled for. Total cardiovascular disease showed a similar pattern as did all stroke.
Conclusions: Heavy drinking appeared to increase the risk of hemorrhagic stroke, in part due to hypertension, and to increase the risk of sudden death, which was probably due to drinking per se. Light or moderate alcohol consumption seemed to protect against nonhemorrhagic stroke and coronary heart disease.