Taking ASA regularly helps reduces the overall risk of death in older women prone to heart disease, a large new study suggests.

Taking ASA regularly helps reduces the overall risk of death in older women prone to heart disease, a large new study suggests.
(CBC)

Acetylsalicylic acid saves lives among people who have had a heart attack or stroke, and reduces the risk of dying for healthy men, but the evidence for healthy women is more contradictory and confusing.

In Monday's Archives of Internal Medicine, researchers concluded that older women taking low to moderate doses of ASA regularly had a 25-per-cent lower risk of death from all causes during the 24 year-long study.

Dr. Andrew Chan and colleagues at Harvard Medical School in Boston, Mass., followed nearly 80,000 nurses in the U.S. from 1980 to 2004. Participants were asked every two years about how often they took the drug and how much.

Women who chose to take ASA showed a 38 per cent lower risk of death from cardiovascular disease, and a 12-per-cent reduced risk of death from cancer compared with those who did not take the drug regularly, the team found.

The women had an average age of 46 when the study began and had no history of heart disease or cancer. They were about 70 years old by the time the study ended.

Age difference

The benefits were greater in women over 60 and those at moderate to high risk.

It's these older women who may gain from taking a "baby" 81-milligram dose of ASA in addition eating a low-fat diet, maintaining a healthy body weight, exercising regularly, and treating high blood pressure, said cardiologist Dr. Beth Abramson of the Heart and Stroke Foundation of Canada.

"A 50-year-old woman is just at low to average risk," Abramson said. "Her risk will start increasing after menopause and midlife. Women develop heart disease and stroke on average seven to 10 years later than men."

Earlier research, including a study published in 2005 on nearly 40,000 women, concluded ASA did not reduce the risk of death in healthy women. But that study focused on younger women, said Abramson, who said that conclusion may not apply to older women.

Since the latest study was observational rather than the gold standard approach of randomly assigning people to take a drug or a placebo, the findings do not prove a cause-and-effect relationship, cautioned study co-author Dr. JoAnn Mason of Brigham and Women's Hospital in Boston.

It is also possible that nurses who chose to take ASA may have been more health conscious overall.

ASA is considered fairly safe aside from a risk of ulcers and bleeding. Each woman should talk to her doctor about her individual risk profile and whether ASA therapy is appropriate.

With files from the Associated Press