Clinical question: Is the combination of aspirin and clopidogrel effective in reducing stroke recurrence?
Background: The risk of recurrent stroke varies from 3% to 15% in the 3 months after a minor ischemic stroke (score of 3 or less) or high-risk transient ischemic attack ( score of 4 or less). Dual-antiplatelet therapy with aspirin and clopidogrel reduces recurrent coronary syndrome; therefore, this strategy can prevent recurrent stroke.
Study design: Prospective, randomized, double-blind, multicenter, placebo-controlled trial.
Setting: 269 sites in 10 countries, mostly in the United States, from May 28, 2010, to Dec. 19, 2017.
Synopsis: The(Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke) trial enrolled 4,881 patients older than 18 years of age randomized to a loading dose of 600 mg of clopidogrel followed by 75 mg per day or placebo, and aspirin 162 mg daily for 5 days followed by 81 mg daily. The primary outcome was the risk of major ischemic events, including ischemic stroke, myocardial infarction, or death from ischemic vascular causes. Major ischemic events were observed in 5.0% receiving dual therapy and in 6.5% of those receiving aspirin alone (hazard ratio, 0.75; 95% confidence interval, 0.59-0.95; P = .02) with most occurring within a week after the initial stroke. Major hemorrhage occurred in only 23 patients (0.9%), most of which were extracranial and nonfatal. One of the main limitations is the difficulty in objectively diagnosing TIAs, accounting for 43% of the patients in the study.
Bottom line: Dual-antiplatelet therapy with aspirin and clopidogrel is beneficial, mainly in the first week after a minor stroke or high-risk TIA with low risk of major bleeding.
Citation: Johnston SC et al. Clopidogrel and aspirin in acute ischemic stroke and high-risk TIA..
Dr. Vela-Duarte is assistant professor of neurology at the University of Colorado, Denver.