The blood thinner clopidogrel, when used with aspirin, reduces the short term and long term risk of heart attack, stroke, and death among more than 12000 emergency department patients in 28 countries, a study shows.
The study by Dr Salim Yusuf and colleagues, in the rapid track section of the online version of Circulation, says that the drug showed beneficial effects within 24 hours of start of treatment and that the benefit continued for 12 months (http://www.circ.aha.journals.org).
The report concludes: “Other than aspirin, clopidogrel is the only antithrombotic agent that has been demonstrated to be of benefit both in the early phase and during long-term treatment in ACS [acute coronary syndromes].”
“Other oral antithrombotic therapies have been found to be harmful (eg, oral glycoprotein IIb/IIIa inhibitors), ineffective, or poorly tolerated (eg, oral anticoagulants),” it says. “Therefore, both aspirin and clopidogrel should be initiated early (along with thrombin inhibitors and glycoprotein IIb/IIIa inhibitors in those undergoing interventions) and continued for the long term (with statins, ACE inhibitors, and, where appropriate, beta-blockers). The combined use of these treatments will lead to the greatest benefits in the largest number of patients.”
The trial compared clopidogrel with placebo in 12562 patients. Patients had an average age of 64 years, and 38% were women. All patients were treated with aspirin. Patients who were also treated with clopidogrel were given an immediate dose of 300 mg, then 75 mg each day for up to a year.
In the first 30 days 343 patients (5.4%) in the placebo group died from a cardiovascular cause or had a myocardial infarction or stroke, compared with 270 (4.3%) in the clopidogrel group (relative risk 0.79 (95% confidence interval 0.67 to 0.92)). Between 31 days and 12 months the corresponding percentages were 6.3% in the placebo group and 5.2% in the clopidogrel group (0.82 (0.70 to 0.95)).
On the basis of the study's criteria, 1.18% of placebo patients and 1.75% of clopidogrel patients had a major bleed (relative risk 1.48, 1.1 to 1.99; absolute excess 0.57% over a mean of eight months).
Dr Shamir Mehta, assistant professor of medicine at McMaster University in Hamilton, Ontario, and a coauthor of the study, said: “It is important to note the apparent universality of these results.”