A new study published in The New England Journal of Medicine shows that low doses of aspirin do not prevent first heart attacks in women under 65, as they do in men.

Earlier research, which focused mostly or entirely on men, indicated that aspirin prevents heart attacks. But the 10-year Women's Health Study, which followed 40,000 women, showed that aspirin does not prevent heart attacks in women. However, it does prevent strokes caused by blood clots, a benefit that has not been conclusively proven in men.

Women in the control group had the same number of heart attacks as the women in the aspirin group. But the number of strokes in the aspirin group was 17% lower. And the aspirin takers had a whopping 24% lower risk of ischemic stroke—the most common kind, caused by a blood clot in an artery leading to the brain. However, the risk of hemorrhagic stroke—caused by bleeding—was slightly higher in the aspirin group. (This was expected, because aspirin reduces blood's ability to clot.)

Both ischemic strokes and heart attacks are caused by blood clots in arteries, so it isn't clear why aspirin only protects women against strokes. The explanation may have something to do with the size of the blood vessels that lead to the brain, which are smaller than those leading to the heart, but no one knows yet for sure.

Because aspirin therapy increases the risk of bleeding, doctors don't currently advise men or women with no risk of heart disease to take aspirin as a preventive measure. Women with risk factors for heart disease (they're over 65, they smoke, have high blood pressure, are diabetic, or have a family history of cardiovascular problems) are often told to take a baby aspirin every day. That probably won't change.

But now doctors can fine-tune the way they manage patients with cardiovascular risk, knowing that women under 65 are more vulnerable to certain kinds of stroke.

You can read the New York Times article about the study here

You can read an abstract of the article in The New England Journal of Medicine here

What do you think about research that shows that some drugs affect women differently than men? Should drug studies have to include equal numbers of men and women? Or should they look at men and women separately? How about different ethnic groups? Or children?

All tags:

Tags : cardiovascular men health gender heart women

How would you tag this story?

My tags:

• Email