Background and purpose: Light-to-moderate alcohol consumption has been consistently associated with lower risk of heart disease, but data for stroke are less certain. A lower risk of stroke with light-to-moderate alcohol intake has been suggested, but the dose response among women remains uncertain and the data in this subgroup have been sparse.
Methods: A total of 83 578 female participants of the Nurses' Health Study who were free of diagnosed cardiovascular disease and cancer at baseline were followed-up from 1980 to 2006. Data on self-reported alcohol consumption were assessed at baseline and updated approximately every 4 years, whereas stroke and potential confounder data were updated at baseline and biennially. Strokes were classified according to the National Survey of Stroke criteria.
Results: We observed 2171 incident strokes over 1 695 324 person-years. In multivariable adjusted analyses, compared to abstainers, the relative risks of stroke were 0.83 (95% CI, 0.75-0.92) for <5 g/d, 0.79 (95% CI, 0.70-0.90) for 5 to 14.9 g/d, 0.87 (0.72-1.05) for 15 to 29.9 g/d, and 1.06 (95% CI, 0.86-1.30) for 30 to 45 g/d. Results were similar for ischemic and hemorrhagic stroke.
Conclusions: Light-to-moderate alcohol consumption was associated with a lower risk of total stroke. In this population of women with modest alcohol consumption, an elevated risk of total stroke related to alcohol was not observed.