Comparison of Antiplatelet Monotherapies After Percutaneous Coronary Intervention According to Clinical, Ischemic, and Bleeding Risks

BACKGROUND Clopidogrel was superior to aspirin monotherapy in secondary prevention after percutaneous coronary intervention (PCI).OBJECTIVES The purpose of this study was to evaluate the benefits of clopidogrel across high-risk subgroupsMETHODS This was a post hoc analysis of the HOST-EXAM (Harmonizing Optimal Strategy for Treatment of coronary artery diseases-EXtended Antiplatelet Monotherapy) trial that randomly assigned patients who were event free for 6 to 18 months post-PCI on dual antiplatelet therapy (DAPT) to clopidogrel or aspirin monotherapy. Two clinical risk scores were used for risk stratification: the DAPT score and the Thrombolysis In Myocardial Infarction Risk Score for Secondary Prevention (TRS 2(degrees)P) (the sum of age >= 75 years, diabetes, hypertension, current smoking, peripheral artery disease, stroke, coronary artery bypass grafting, heart failure, and renal dysfunction). The primary composite endpoint was a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission because of acute coronary syndrome, and major bleeding (Bleeding Academic Research Consortium type >= 3) at 2 years after randomization.RESULTS Among 5,403 patients, clopidogrel monotherapy showed a lower rate of the primary composite endpoint than aspirin monotherapy (HR: 0.73; 95% CI: 0.59-0.90). The benefit of clopidogrel over aspirin was consistent regardless of TRS 2(degrees)P (high TRS 2(degrees)P [>= 3] group: HR: 0.65 [95% CI: 0.44-0.96]; and low TRS 2(degrees)P [<3] group: HR: 0.77 [95% CI: 0.60-0.99]) (P for interaction = 0.454) and regardless of DAPT score (high DAPT score [>= 2] group: HR: 0.68 [95% CI: 0.46-1.00]; and low DAPT score [<2] group: HR: 0.75 [95% CI: 0.59-0.96]) (P for interaction = 0.662). The association was similar for the individual outcomes.CONCLUSIONS The beneficial effect of clopidogrel over aspirin monotherapy was consistent regardless of clinical risk or relative ischemic and bleeding risks compared with aspirin monotherapy.

Automated summary

This study found that clopidogrel was superior to aspirin monotherapy in high-risk subgroups following percutaneous coronary intervention (PCI), regardless of clinical risk or relative ischemic and bleeding risks.