Can taking aspirin help prevent the development of cardiovascular disease?

Does aspirin therapy afford the same benefits (or risks) to men and women? The questions are timely, as it is known that taking aspirin reduces the risk of cardiovascular disease among individuals who have preexisting cardiovascular conditions.

A study published in the Jan. 18, 2006, Journal of the American Medical Association gives insights on the prophylactic benefit of aspirin therapy.

Led by Jeffrey S. Berger, M.D., M.S., researchers from Duke University performed a statistical review of published studies on the benefits of aspirin therapy for primary prevention of cardiovascular disease. The review also sought to provide information on the effect of aspirin therapy among women - an area of limited analysis.

Overall, aspirin therapy was found to reduce the risk of stroke in women and reduce the risk of heart attack in men. However, aspirin use was associated with a significant risk of major bleeding in both genders.

"Primary prevention" refers to the performance of activities designed to reduce the occurrence of disease - as opposed to "secondary prevention," which involves action to mitigate the progress or recurrence of a condition that has already developed or occurred. In this study, the efficacy of aspirin therapy was measured by the prevention of any major cardiovascular event (nonfatal heart attack, nonfatal stroke, cardiovascular death).

The retrospective review pooled data from selected studies for analysis purposes. Researchers began with the selection of 102 potentially relevant studies from available databases. From this, six randomized and controlled trials were deemed worthy of study inclusion - amounting to an enrollment of 95,456 individuals. Three trials included only men, one trial included only women and two trials included both sexes.

Researchers found that among the 51,342 women, aspirin reduced the incidence of stroke by 17 percent, yet it did not statistically affect the occurrence of heart attack or cardiovascular death. Among men, aspirin was found to reduce heart attacks by 32 percent but was not a significant aid to reducing stroke or cardiovascular death. Aspirin therapy did increase the risk of bleeding by 70 percent for both genders.

To put the numbers in perspective, the authors concluded that taking aspirin for an average of 6.4 years results in the prevention of three cardiovascular events per 1,000 women and four cardiovascular events per 1,000 men. Furthermore, taking aspirin for 6.4 years results in an increase of two and a half major bleeding events per 1,000 women and three major bleeding events per 1,000 men.

As the authors noted, this study has limitations. Women have a proportionally higher rate of strokes than men, and men have more heart attacks as compared to strokes. Because of this, additional research is needed to truly ascertain if there is a gender difference regarding the benefits of aspirin therapy. Still, the results support emerging evidence that some medicines affect women in a different manner than men.

"This type of information is a reaffirmation of previous data, which shows that there are clearly gender-specific responses to therapy. There is not a one-size-fits-all approach to medicine, and the data here shows that men and women clearly react differently to a very simple and commonly used medication - aspirin," said Michael Watkins, M.D., a practicing interventional cardiologist and chief clinical officer and co-chair of the Heart Disease Channel for Revolution Health Group's Medical Advisory Board.

Indeed, the discovery of a gender-specific aspirin regimen supports the pharmacogenetic concept that the influence of a particular medication for any individual may vary because of genetic differences.

"When confronted with the need to take a particular medicine, it is certainly worth asking what data are available that justify its use in a particular patient. Much more tailored approaches to medication usage need to happen in the future. This should allow for optimal benefit with minimal risk," Watkins added.

Although this study has many restrictions, the authors believe that aspirin use has a favorable effect on the reduction of cardiovascular events among men and women. However, given that aspirin use is associated with a significant risk of bleeding, patients should always consult their physicians before initiating aspirin therapy.

© 2006 MyDNA.com