Impact of the ABCD‐GENE Score on Clopidogrel Clinical Effectiveness after PCI: A Multi‐Site, Real‐World Investigation

<jats:p>The <jats:bold>A</jats:bold>ge, <jats:bold>B</jats:bold>ody mass index, <jats:bold>C</jats:bold>hronic kidney disease, <jats:bold>D</jats:bold>iabetes mellitus, and <jats:italic>CYP2C19</jats:italic> <jats:bold>GENE</jats:bold>tic variants (ABCD‐GENE) score was developed to identify patients at risk for diminished antiplatelet effects with clopidogrel after percutaneous coronary intervention (PCI). The objective of this study was to validate the ability of the ABCD‐GENE score to predict the risk for atherothrombotic events in a diverse, real‐world population of clopidogrel‐treated patients who underwent PCI and received clinical <jats:italic>CYP2C19</jats:italic> genotyping to guide antiplatelet therapy. A total of 2,341 adult patients who underwent PCI, were genotyped for <jats:italic>CYP2C19</jats:italic>, and received treatment with clopidogrel across four institutions were included (mean age 64 ± 12 years, 35% women, and 20% Black). The primary outcome was major atherothrombotic events, defined as the composite of all‐cause death, myocardial infarction, ischemic stroke, stent thrombosis, or revascularization for unstable angina within 12 months following PCI. Major adverse cardiovascular events (MACE), defined as the composite of cardiovascular death, myocardial infarction, ischemic stroke, or stent thrombosis, was assessed as the secondary outcome. Outcomes were compared between patients with an ABCD‐GENE score ≥ 10 vs. < 10. The risk of major atherothrombotic events was higher in patients with an ABCD‐GENE score ≥ 10 (<jats:italic>n</jats:italic> = 505) vs. < 10 (<jats:italic>n</jats:italic> = 1,836; 24.6 vs. 14.7 events per 100 patient‐years, adjusted hazard ratio (HR) 1.66, 95% confidence interval (CI), 1.23–2.25, <jats:italic>P</jats:italic> < 0.001). The risk for MACE was also higher among patients with a score ≥ 10 vs. < 10 (16.7 vs. 10.1 events per 100 patient‐years, adjusted HR 1.59, 95% CI 1.11–2.30, <jats:italic>P</jats:italic> = 0.013). Our diverse, real‐world data demonstrate diminished clopidogrel effectiveness in post‐PCI patients with an ABCD‐GENE score ≥ 10.</jats:p>