Benefits and risks of adding clopidogrel to aspirin therapy

This study investigated the benefits and risks of adding clopidogrel (Plavix) to aspirin in people at high risk of getting heart disease or having a stroke, and in people who already have heart disease. It was determined that the combination reduced the risk of heart attacks and stroke, but had no effect on mortality, and increased the risk of bleeding. 

Aspirin and clopidogrel are drugs that can be used to reduce the risks of heart attacks and strokes. They act as blood thinners and block the initial stages of blood clotting. Aspirin is used more commonly, but only has small benefits for people at high risk of getting heart disease. Adding a second drug (like clopidogrel) may provide additional benefit for these people, and patients who have already been diagnosed. 

This study examined data from 15 other studies that compared the use of aspirin plus clopidogrel with aspirin plus a placebo (drug with no active effect) or aspirin alone. 33,970 people at high risk of getting heart disease or having a stroke, or those who already had heart disease, were examined. In the studies, participants were randomly assigned to the intervention group (aspirin plus clopidogrel) or the control group (aspirin plus placebo, or aspirin alone). They were followed for 6 weeks to 3.4 years, depending on the study.

Aspirin plus clopidogrel and aspirin alone or with placebo were equally effective in reducing death from cardiac causes and from all causes. Patients in the intervention group were 22% less likely than the control group to have a fatal or non-fatal heart attack. They were also 27% less likely than the control group to have a fatal or non-fatal stroke.

Patients in the intervention group were 44% more likely than the control group to experience major bleeding, and more than twice as likely to experience minor bleeding. This risk was slightly higher in patients in the control group who had previously had a stroke.

The study concluded that adding clopidogrel to aspirin therapy reduced the risk of heart attacks and stroke. However, the combination increased the risk of bleeding, and did not affect the rate of death from cardiac or from all causes.  

People who had recently had coronary stents (flexible tubes inserted into blood vessels to keep them open) inserted were not included in this review. Thus the results will not apply to all people with heart disease. Pharmaceutical companies funded some of the studies examined in this study.

Discuss the risks and benefits of adding clopidogrel to aspirin therapy with your physician.