Women: Rethink your aspirin a day

Low-dose aspirin may curb the risks of heart disease and colon cancer, but for many women, the risks appear to outweigh the benefits, a recent large study suggests.

Over a 15-year period, researchers assigned a group of 28,000 healthy female health professionals to take either 100 milligrams of aspirin every other day or a placebo on the same schedule.

For those younger than 65, researchers found taking low-dose aspirin for years lowered the risks of heart attack, stroke and colon cancer. But they also found that an increased risk of major gastrointestinal bleeding, serious enough to land a woman in the hospital.

For women over 65, researchers concluded that the benefit of aspirin outweighs the risk. Moreover, using a formula that includes many health and behavioral factors collected in the study — age, smoking, blood pressure, cholesterol and more than two dozen others — the researchers were able to create a personalized estimate of risk for a given patient. The study was published online in a December 2014 issue of the journal Heart.

Many women are under the impression it’s a good idea to take aspirin every day, says Dr. Robert Johnson, a cardiologist at Advocate Condell Medical Center in Libertyville, Ill.

“Aspirin can be a lifesaver for people who’ve already had a heart attack,” Dr. Johnson says. But its preventive value is unclear, he says.

According to Nancy Cook, one of the researchers, the risks may not be worth it for most women younger than 65.

“I probably wouldn’t take aspirin unless I had a very high risk of either cardiovascular disease or colon cancer,” Cook said, a professor of medicine at Harvard Medical School and Brigham & Women’s Hospital in Boston, in a published report.

About 11 percent of the women in the study either developed cancer, suffered a heart attack or stroke, or died of cardiovascular disease, according to the study.

The researchers estimate that in the under-65 group, for every 133 women on aspirin for 15 years, one would suffer a major gastrointestinal bleeding episode serious enough to warrant a hospital stay. One out of 29 women would have less serious problems like a stomach ulcer or slight bleeding in the digestive tract.

In comparison, 709 women would have to take aspirin to prevent one case of colon cancer and 371 would have to regularly take the drug to prevent one cardiovascular complication, according to the study.

Among those age 65 and up, only 29 would need to take aspirin long-term to prevent a case of cardiovascular disease or cancer.

“The bottom line,” Dr. Johnson says, “is people need to have a careful discussion with a doctor they trust.”