By Merritt McKinney
NEW YORK, Sep 02 (Reuters Health) -- Healthy women who take one to six aspirin tablets a week may cut their risk of having the most common type of stroke, according to a new study.
However, too much of a good thing may be dangerous, since the same study showed that women who took 15 or more aspirin a week were more likely to have a less common type of stroke.
It has been shown that women who have had a stroke can reduce their risk of having a second one by taking aspirin, according to senior author Dr. JoAnn E. Manson, a professor of medicine at Harvard Medical School and Brigham and Women's Hospital in Boston, and colleagues. However, it is been unclear whether healthy women also benefit from an aspirin a day.
To test the effect of aspirin, the researchers followed 79,319 women between the ages of 34 to 59 who were enrolled in the Nurses' Health Study, a large, ongoing trial of more than 120,000 nurses. None of the women followed by Manson's team had diseases that are treated with regular doses of aspirin, such as heart disease or rheumatoid arthritis.
After tracking the women's aspirin use and health for 14 years, the researchers found that aspirin appeared to offer protection against the most common type of stroke, known as an ischemic stroke. This type of stroke occurs when arterial disease cuts off blood supply to the brain. Women who took one to six aspirin tablets a week were less likely to have this kind of stroke, according to the report in the September issue of the journal Stroke: Journal of the American Heart Association.
However, taking 15 or more aspirin tablets a week nearly doubled a woman's odds of having a hemorrhagic stroke, which is caused by excessive bleeding in the brain. And the risk was tripled in older women and those with high blood pressure who took this much aspirin, according to the report.
"This study indicates that it may be a good news - bad news situation in terms of the primary prevention of stroke," Manson said in a statement.
"If low doses of aspirin reduce the risk of ischemic stroke in healthy individuals, this is important, since it is the most prevalent form of stroke," she said. "On the other hand, our findings suggest that taking too much aspirin could be dangerous," Manson noted.
"Less is probably more" when it comes to aspirin, Manson told Reuters Health in an interview.
However, she noted, "The jury is still out on whether women should take aspirin for the... prevention of stroke."
"The real bottom line is that no one should begin taking aspirin without talking to their physician," she said.
Manson noted that she and her colleagues are involved in an ongoing trial testing the effects of aspirin on stroke prevention in a group of 40,000 female health professionals. The results of that study, which should be available in two years, may help clear up the issue, she said.
