Log in to MyACC
Comparison of Antiplatelet Monotherapies After PCI
Quick Takes
- The HOST-EXAM trial showed that clopidogrel monotherapy was superior to aspirin for chronic maintenance therapy among patients who had undergone PCI and the required post-PCI DAPT. The current post hoc analysis from that trial compared aspirin vs. clopidogrel monotherapy for chronic maintenance stratified by ischemic and bleeding risk.
- Patients were stratified using the DAPT and TRS 2°P risk score.
- Findings showed clopidogrel maintenance therapy to be superior to aspirin monotherapy across the spectrum of ischemic or bleeding risk among East Asian patients.
Study Questions:
Is clopidogrel monotherapy superior to aspirin across specific subgroups stratified by ischemic and bleeding risk?
Methods:
This was a post hoc analysis of the HOST-EXAM (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis–Extended Antiplatelet Monotherapy) trial that randomly assigned patients who were event free for 6-18 months post–percutaneous coronary intervention (PCI) on dual antiplatelet therapy (DAPT) to clopidogrel or aspirin monotherapy. Two clinical risk scores were utilized for risk stratification, the DAPT score and the Thrombolysis in Myocardial Infarction Risk Score for Secondary Prevention (TRS 2°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 due to 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 (hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.59–0.90). The benefit of clopidogrel over aspirin was consistent regardless of TRS 2°P (high TRS 2°P [≥3] group: HR, 0.65; 95% CI, 0.44–0.96 and low TRS 2°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 as compared to aspirin monotherapy.
Perspective:
The HOST-EXAM randomized controlled trial (RCT) showed that clopidogrel monotherapy was superior to aspirin for chronic maintenance therapy among patients who had undergone PCI and the required post-PCI DAPT. The current post hoc analysis from the HOST-EXAM RCT compared aspirin versus clopidogrel stratified by ischemic and bleeding risk. They stratified patients using the DAPT and TRS 2°P risk score and showed clopidogrel maintenance therapy to be superior to aspirin monotherapy across the spectrum of ischemic or bleeding risk among East Asian patients. Findings have to be evaluated in the context of limitations posed by retrospective study design and specific population (trial only included East Asians). Further study will be needed to confirm these findings among a broader population.
Clinical Topics: Invasive Cardiovascular Angiography and Intervention
Keywords: Aspirin, Myocardial Ischemia, Percutaneous Coronary Intervention, Platelet Aggregation Inhibitors, Risk Assessment
< Back to Listings
