A long-awaited study has shown that low-dose aspirin therapy considerably reduces the risk of stroke in women. However, it lowers the rates of heart attack and other cardiac problems only in women age 65 and older.
The Study
The report comes from the decade-long Women's Health Study, which included nearly 40,000 middle-aged and older women. This was the first trial whose size was similar to preventive studies that had been conducted in men.
The study found that aspirin reduced the risk for all types of stroke by 17%. For ischemic stroke, which is caused by a blockage in a brain artery, risk was reduced by 24%.
The benefit of low-dose aspirin in preventing cardiovascular problems was concentrated in the 10% of study participants who were age 65 and over. Among these women, low-dose aspirin reduced the risk of a cardiovascular event by 26% compared with women taking a placebo.
The results differed from those found in similar large-scale studies of men, in which aspirin has been found to lower the risk of a first-time heart attack but have little effect on the risk of stroke.
Vitamin E Benefit?
Because some previous studies have shown a benefit from taking vitamin E, some women who participated in the trial were given 600 international units (IU) of vitamin E daily.
"The conclusion was that there is no benefit for cardiovascular disease in taking vitamin E," says Julie E. Buring, a professor of medicine at Brigham and Women's Hospital and Harvard Medical School. "It is better just to eat heart-healthy foods.
Caution Urged
Women of all ages and their physicians will have to balance the benefits and risks of low-dose aspirin, she says.
During the study, there were 127 bleeding episodes that required transfusion among the women taking aspirin compared with 91 such events among those taking a placebo.
This difference in risk is statistically significant and must be considered when making a decision, Buring says.
Similar sentiments were echoed by Dr. Elizabeth G. Nabel, director of the National Heart, Lung, and Blood Institute (NHLBD), which supported the study.
Consult your doctor, Nabel says. "Above all," she adds, women, like men, should adopt the well-proven approaches that reduce the risk of heart disease—eating for heart health, getting regular physical activity, maintaining a healthy weight, not smoking and controlling high cholesterol, high blood pressure and diabetes."