Long-term aspirin and death risk for women: new study

Women who took low to moderate daily doses of aspirin had a reduced death rate, especially from heart disease, according to decades-long research. The research, based on data from a major trial that has tracked almost 80,000 women since 1976, found women who reported using aspirin on a regular basis had a 25% lower risk of death from any cause than women who didn't take the drug.

The risk of death from cardiovascular disease was 38% lower for aspirin users, and there was also a 12% reduction in cancer deaths that took effect after a decade of aspirin use, the researchers found in their report based on the Nurses' Health Study.

The results were published in the March 26 issue of the Archives of Internal Medicine.

However, an accompanying editorial in the journal cautioned that the results were open to debate and far from definitive.

The dissenting editorial, by Dr John A. Baron of Dartmouth Medical School, was based in large part on results of a different trial, the Women's Health Study, which followed almost 40,000 women for 11 years and found no reduction in overall deaths or cardiovascular mortality associated with aspirin therapy.

Therefore, Baron said, the new findings "cannot overcome the accumulated evidence that aspirin is not particularly effective for the primary prevention of death from cardiovascular disease in women."

"This is a complicated issue," said Dr Andrew T. Chan, an assistant professor of medicine at the Harvard Medical School, and lead author of the new report. "We understand that aspirin has potential health benefits, but who would aspirin therapy be appropriate for?" There are "areas of disagreement that need further study" before that question can be answered, Chan said. But there is information from the two large studies and other trials that can help guide women and their physicians, he said.

For starters, some studies suggest aspirin has benefits for older women and those who have cardiovascular risk factors such as high blood pressure, diabetes, high cholesterol and obesity, Chan said. "Our study and the Women's Heath Study do suggest that there is a potential role of aspirin for women who have subclinical cardiovascular disease," he added.

That statement meshes with prevention guidelines issued in 2004 by the American Heart Association. The guidelines recommend aspirin for women at high risk of heart disease or who already have cardiovascular disease, but they don't apply to women at low risk for the disease. For intermediate-risk women, aspirin can be considered if blood pressure is under control and the benefits are believed to outweigh risks, such as gastrointestinal bleeding.

But the decision to take aspirin, or any other medication, should not be made by an individual alone, Chan said. "I tell women that, at this point, the decision calls for consultation with a doctor," he said. "Aspirin does have side effects, so it is something that has to be individualized. It would be very naive to recommend that treatment for all women across the board."

The new study included information on 29,000 participants in the Nurses' Health study who took between one and 14 standard 325mg aspirin tablets a week and 5002 women who took more than 14 tablets weekly.

The reduction in cancer risk that became evident after 10 years was an intriguing finding, Chan said. The Women's Health Study found no such reduction over a decade, he said. "One important message is that the study suggests the mechanisms at play for cardiovascular disease and cancer are potentially common," Chan said. "This provides further grounds for research into these mechanisms."

Dr Jeffrey Berger, a cardiology fellow at Duke University who has done related research, said the new report describes "another very large study that tells us individuals who take aspirin live longer. You can't argue with that. We can't prove cause-and-effect, but we can say that when you take aspirin, there is a reduction in overall deaths."

It's important to remember that aspirin has benefits for both men and women, Berger added. "How it benefits men, how it benefits women, that is an important issue at this time," he said.

And anyone who is thinking about daily aspirin "should really talk with doctors about the benefits and risks," Berger said.