Aspirin disappoints for avoiding first heart attack, stroke

Taking a low-dose aspirin every day has long been known to cut the chances of another heart attack, stroke or other heart problem in people who have already had one, but the risks don’t outweigh the benefits for most other folks, major new research finds.

Aspirin’s value in many situations is still unclear. The latest studies are some of the largest and longest to test this pennies-a-day blood thinner in people who don’t yet have heart disease or a blood vessel-related problem.

One found that aspirin did not help prevent first strokes or heart attacks in people at moderate risk for one because they had several health threats such as smoking, high blood pressure or high cholesterol.

Another tested aspirin in people with diabetes, who are more likely to develop or die from heart problems, and found that the modest benefit it gave was offset by a greater risk of serious bleeding.

Aspirin did not help prevent cancer as had been hoped.

“There’s been a lot of uncertainty among doctors around the world about prescribing aspirin” beyond those for whom it’s now recommended, said one study leader, Dr. Jane Armitage of the University of Oxford in England. “If you’re healthy, it’s probably not worth taking it.”

The aspirin studies used 100 milligrams a day, more than the 81-milligram pills commonly sold in the United States but still considered low dose.

Adult strength 325 milligrams.

A Boston-led study gave aspirin or dummy pills is to 12,546 people who were thought to have a moderate risk of suffering a heart attack or stroke within a decade because of other health issues.

After five years, 4 percent of each group had suffered a heart problem — far fewer than expected, suggesting these people were at low risk, not moderate.