For years, the jury has been out about whether low-dose aspirin gives women the same kind of cardiovascular protection as it does men. In March 2005, a verdict came in but was mixed. Nothing is simple in medicine, not even a little old aspirin.
Results from the Women's Health Study led by Harvard researchers showed that women under age 65 who took a 100-milligram (mg) dose of aspirin every other day did not lower their chances of a having a first-ever heart attack. Moreover, the aspirin routine was associated with a fairly substantial risk of gastrointestinal bleeding. But there are two major wrinkles to consider: First, although it didn't help with heart attacks, the low-dose regimen did lower (by 17%) first-ever stroke risk. And second, among the women in the study who were 65 and over, it lowered first-ever stroke and heart attack risk.
As the headlines at the time noted, the main finding is just the opposite of what has been seen with middle-aged men. Starting at about age 50, low-dose aspirin seems to protect men against first-ever heart attacks, but may slightly increase stroke risk.
So who should be taking aspirin for preventive cardiovascular purposes? You need to talk to a doctor about your individual situation. Generally speaking, anybody who has cardiovascular disease is a candidate for life-long, low-dose aspirin. Other people who should consider taking aspirin regularly include:
men over age 40 with several risk factors for having a heart attack.
men starting in their 50s, even if they don't have cardiovascular risk factors.
women starting at about age 65, because, that's when the cardiovascular benefits of aspirin outweigh its drawbacks, which are mainly related to bleeding.
men and women with diabetes with at least one other cardiovascular risk factor.
Borderline cases include men in their 40s who have a slightly elevated chance of having a heart attack and women under 65 with stroke risk factors such as hypertension. Most doctors don't recommend aspirin for women without stroke risk factors because the benefit is offset by the bleeding risks.
June 2005 Update
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