A study of more than 80,000 women found that low to moderate alcohol consumption was associated with a 17% to 21% reduction in risk of stroke.…
Kathryn M. Rexrode, MD, MPH, from Brigham and Women’s Hospital in Boston, and colleagues found that, compared with women who didn’t drink, the relative risk of stroke ranged from 0.83 for drinking less than 5 grams per day (g/d) to 0.79 for those who consumed up to 15 g/d. Thebenefit was the same for ischemic or hemorrhagic stroke, they reported.
The investigators noted that previous associations have been seen with light to moderate drinking and reduced stroke risk. However, they said that many studies did not take into account the stroke type, nor did they break down drinking according to the amount.
In addition, most studies relied on one baseline assessment of drinking, which doesn’t account for changing patterns of consumption over time.
The findings emerged from a study of 83,578 women, ages 30 to 55, who were enrolled in the Nurses’ Health Study. The researchers parsed the data according to former drinkers, abstainers, and current drinkers, as well as the amount consumed. They adjusted for a variety of potential confounders including age, smoking, hormone use, aspirin use, hypertension, and history of atrial fibrillation.
Participants completed a baseline questionnaire in 1976 and one thereafter approximately every four years, which contained data on their alcohol consumption. The mean age at baseline was 46 and all participants in this study were free of diagnosed cardiovascular disease and cancer. Follow-up ended in 2006.
Thirty percent of the women were nondrinkers and 35% drank less than a half glass a day. Just 4% said they drank two to three glasses a day, and the remainder drank one to two glasses daily. And compared with abstainers, heavier alcohol consumption was associated with smoking, a history of hypertension, increased physical activity, and a lower body mass index.
During the 26 years of follow-up, there were 1,206 ischemic and 363 hemorrhagic strokes. Another 602 were of probable/unknown subtype. Compared with abstainers, those who were light to moderate drinkers — a half glass to a glass and a half — had a lower total risk of stroke in the fully adjusted model (HR 0.83 and 0.79, respectively).
Those who drank between two glasses daily had a decreased risk of total stroke, although higher than the low and moderate groups (HR 0.86). For ischemic stroke, the hazard ratios were 0.88, 0.86, and 0.82, respectively, and for hemorrhagic they were 0.82, 0.76, and 0.88, respectively.
The heaviest drinkers — two to three glasses a day — had an increased total and ischemic stroke risk (HR 1.06 and 1.17, respectively) but a slight decreased risk for hemorrhagic stroke (HR 0.97).
Researchers did not find any significant differences when data were stratified by age, hypertension, aspirin use, hormone therapy, or smoking. However, moderate drinkers without a history of atrial fibrillation had a lower risk of total stroke.
Results were similar in an adjusted model that did not include hypertension, and they were similar between the different alcohol types. The risk of stroke also was similar for those who drank but gave it up for various reasons.
These results are generally consistent with other studies in terms of the overall lower risk for low and moderate drinkers, with an increased risk for heavier drinkers, when compared with abstainers, Rexrode and colleagues said.
They suggested that lower levels of alcohol consumption may be anti-thrombotic and atherogenic, “leading to increased high-density lipoprotein, decreased platelet aggregation, clot formation, and increased fibrinolysis.”
- Explain that the benefit of low to moderate alcohol consumption on reduced stroke risk was the same for ischemic or hemorrhagic stroke.
- Note that a study of more than 80,000 women found that low to moderate alcohol consumption (a half glass to a glass and a half) was associated with a 17% to 21% reduction in risk of stroke.
Jimenez M, et al “Alcohol consumption and risk of stroke in women” stroke 2012; 43: DOI:10.1161/STROKEAHA.111.6394351.