New guidelines for aspirin use, from the Harvard Heart Letter
Aspirin was once used mainly to relieve pain and ease fever. Today it's best known for its ability to protect hearts. Updated recommendations from the U.S. Preventive Services Task Force fill in two big gaps—about aspirin for women and about the safest dose to take. But the new recommendations don't provide a cookie-cutter approach. Instead, they emphasize weighing the benefits of aspirin therapy against the risks, reports the June 2009 issue of the Harvard Heart Letter.
In general, you should consider taking aspirin if its benefits outweigh its risks. It makes the most sense if your chance of having a heart attack or stroke (calculated online or with your doctor) is greater than the odds of aspirin causing a problem. For men, the main benefit is preventing a heart attack. For women, it's preventing ischemic stroke, the most common kind of stroke. For both, the risks are gastrointestinal bleeding and hemorrhagic stroke. The task force sets several tipping points based on age and sex. Although these numbers are helpful, they're impersonal. Your doctor can help you work through the recommendations with your health considerations in mind.
Trials evaluating the heart benefits of aspirin have tested doses ranging from 500 milligrams (mg) a day to 100 mg every other day. The task force says there still isn't enough evidence to say which one is best. But it concludes that a dose of 81 mg a day, the amount in a baby aspirin, seems to work just as well as higher doses, with fewer bleeding problems.