Most of us have heard that men over 50 should consider taking daily aspirin in order to reduce their risk of a heart attack. This recommendation was primarily based on the Physicians Health Study which showed that in the healthy men that were followed, daily aspirin decreased the incidence of first heart attack by as much as 35%. This and other studies have shown, however that “preventative aspirin” has little effect on the risk of stroke in healthy men.
Do these studies apply to women. ..can we be considered “little men”? The answer of course is no… In order to make a gender appropriate recommendation, there must be gender appropriate studies! Only male physicians were included in the Physicians Health Study. But wait, we do have a large study that examined whether aspirin afforded heart attack prevention for healthy women: The Women’s Health Study (WHS) which was reported in 2005. A recent article in the North American Menopause Society Journal reminded physicians of the results of this study and was published under the headline “Practice Pearl”. I thought it would be helpful to review this “pearl” on this week’s website.
The WHS evaluated the benefits and risks of low-dose aspirin (100 mg on alternative days) for the prevention of heart attack, stroke and cardiovascular death among 39,876 initially healthy women age 45 and older who were followed for 10 years. The study demonstrated that aspirin significantly lowered the risk of stroke by 17% and the risk of ischemic stroke (caused by a clot in a cerebral artery which shuts off blood flow to a region of the brain) by 24% in these women. But aspirin DID NOT lower the risk of heart attack or cardiovascular death in healthy women under the age of 65. Moreover, aspirin increased bleeding risks. Gastrointestinal hemorrhage requiring transfusions were 40% more common with aspirin use and there was a 24% increase in the risk of hemorrhagic stroke. The study did show heart benefits for women, but only among those who were age 65 and older. Regular aspirin use was associated with a 26% reduction in the risk of major cardiovascular events, ischemic stroke (risk reduction, 30%) and heart attack (risk reduction, 34%).
These and other studies have definitely shown that aspirin prevents further adverse cardiac events in men and women who have coronary vascular disease, especially if they have had a heart attack. But for primary prevention of heart attack i.e. use of aspirin if you are heart healthy, the study we rely on indicates that women who are under 65 should not routinely take aspirin. Older women are likely to experience a net benefit from daily low dose aspirin unless they have bleeding or allergy contraindications. Most experts would recommended doses between 81-100 mg daily.
Bottom line: Do not routinely take aspirin if you are younger than 65 for coronary protection unless you have an elevated coronary risk, have been diagnosed with coronary artery disease, or have had a heart attack or ischemic stroke. Assess your risk with your physician…diabetes, a strong family history of heart disease, smoking, hypertension and obesity may all contribute to risk.