Association of Age- and Body Mass Index-Stratified High On-Treatment Platelet Reactivity With Coronary Intervention Outcomes in East Asian Patients

BACKGROUND: Although age and body mass index (BMI) significantly affect platelet reactivity units and clinical outcomes after percutaneous coronary intervention, there are limited data on the relationship between high on-treatment platelet reactivity (HPR) and clinical outcomes on age and BMI differences. Thus, we investigated the association of HPR with clinical outcomes according to age and BMI. METHODS AND RESULTS: The study analyzed 11 714 patients who underwent platelet function tests after percutaneous coronary intervention. The primary end point was the occurrence of major adverse cardiac and cerebrovascular events (MACCEs), whereas the secondary end point was major bleeding. HPR was defined as platelet reactivity units ≥252. Patients were categorized by age (<67 years of age or ≥67 years of age) and BMI (≤22.6 kg/m² or >22.6 kg/m²). Patients <67 years of age with HPR had increases in both MACCEs (adjusted hazard ratio [HR], 1.436 [95% CI, 1.106–1.867]; P=0.007) and major bleeding (adjusted HR, 1.584 [95% CI, 1.095–2.290]; P=0.015) compared with the those with non-HPR, respectively. In patients ≥67 years of age with HPR, there were no differences in MACCEs, but there was a decrease in major bleeding (adjusted HR, 0.721 [95% CI, 0.542–0.959]; P=0.024). Meanwhile, patients with HPR with BMI >22.6 kg/m² had increases in MACCEs (adjusted HR, 1.387 [95% CI, 1.140–1.688]; P=0.001). No differences were shown in major bleeding. CONCLUSIONS: HPR was linked to an increase in MACCEs or a decrease in major bleeding in patients after percutaneous coronary intervention, depending on age and BMI. This study is the first to observe that clinical outcomes in patients with HPR after percutaneous coronary intervention may vary based on age and BMI. Because the study is observational, the results should be viewed as hypothesis generating and emphasize the need for randomized clinical trials.