Thursday, June 23, 2011

Aspirin for primary CVD prevention: the continuing debate

In 2002, the U.S. Preventive Services Task Force (USPSTF) strongly recommended that primary care clinicians discuss preventive aspirin use with adults at increased risk of cardiovascular events. Four years later, the National Commission on Prevention Priorities (NCPP) ranked counseling for aspirin use the number one priority on its list of the most effective clinical preventive services. According to the NCPP, if the percentage of eligible patients using aspirin (then estimated to be about 50 percent) increased to 90 percent, 45,000 additional lives could be extended each year.

At that time, the benefits of aspirin use in men and women were assumed to be the same. However, an updated USPSTF recommendation statement published in the June 15th issue of AFP indicates that aspirin use actually prevents heart attacks in men, but ischemic strokes in women. In addition, physicians and patients must weigh the benefits of reduced cardiovascular risk with the risk of gastrointestinal bleeding events, and use shared decision making when these risks are closely balanced.

To further complicate matters, a 2009 meta-analysis published in the journal The Lancet questioned the value of aspirin for primary prevention, concluding that for patients who without a history of cardiovascular disease, "aspirin is of uncertain net value." In response, family physicians and USPSTF members Ned Calonge and Michael LeFevre wrote an editorial that concluded, "There is not a simple message for aspirin prophylaxis as a primary preventive strategy, and we need to consider gender, age, and the associated balance of potential risks and benefits to provide the best advice and preventive care for our patients."

We pick up the continuing debate with two thought-provoking editorials in the June 15th issue. Alison L. Bailey and colleagues caution that routine aspirin use is not justified for primary prevention in adults at low risk of CVD. On the other hand, W. Fred Miser asserts that the main issue regarding aspirin for primary prevention continues to be underuse in appropriate-risk patients. Finally, a Putting Prevention Into Practice case study applies information from the USPSTF recommendation to a sample patient scenario.