Move over aspirin -- just a bit

Clopidogrel marginally more protective in those with multiple cardio events

By Liliana Abbruzee

The prevalence of cardiovascular disease increases with age, with many people developing a cardiac problem in their 40s and 50s. Add to that a rise in Canada's aging population and the stage is set for the highest incidence ever of heart disease and stroke in this country.

By the age of 70, one in five women and one in four men reported having been told by a physician that they had some form of heart condition, according to a recent collaborative report from the Heart and Stroke Foundation, Health Canada and the Canadian Cardiac Society.

Patients who have just had an ischemic stroke or myocardial infarction are at high risk of dying or having another cardiovascular event (CVE) since the underlying disease is still present after patients recover.

New research indicates that the anti-platelet agent clopidogrel appears more effective than aspirin in preventing recurrent CVEs. Researchers analyzed data from the larger Clopidogrel Versus Aspirin in Patients at Risk of Ischemic Events (CAPRIE) trial where 4,496 high-risk patients were followed, all of whom had suffered a second CVE.

At one- and three-year follow-ups, hospitalization and CVE death were less likely to occur with the clopidogrel patients compared to those given aspirin. Of these high-risk patients, the clopidogrel group demonstrated a 14.9% overall risk reduction. The results appear in the February issue of Stroke.

"Basically, if a patient has a history of multiple cardiovascular events, they are better-off being treated with clopidogrel rather than aspirin," said co-author Deepak L Bhatt, MD, director of the Interventional Cardiology Fellowship at the Cleveland Clinic Foundation in Ohio.

Patients who suffer a second CVE are at increased risk for a third and subsequent CVE that may not necessarily be the same as the first. "Unfortunately the third event may be fatal," said Dr Bhatt. "Just because a patient came in with a heart attack today doesn't mean he or she is only at risk for a future heart attack," he added. "The next time, it may be a stroke or other arterial problem."

One year following their second CVE, 16.1% of the clopidogrel group had suffered a stroke or heart attack, or were hospitalized again for a CVE compared to 18.5% in the aspirin group. At the one-year follow-up, 8.8% of the clopidogrel-treated patients versus 10.2% of those taking aspirin had had a stroke, heart attack or died.

After three years, 32.7% of the patients taking clopidogrel and 36.6% of the aspirin group had another CVE. Vascular death occurred in 20.4% of the clopidogrel group and 23.8% of the aspirin-takers. The findings reveal that over a three-year period, treating 29 of these very high-risk patients with clopidogrel would prevent one death, heart attack or stroke.