Evaluation of Potential Racial Disparities inCYP2C19‐Guided P2Y12Inhibitor Prescribing After Percutaneous Coronary Intervention

Black patients suffer worse outcomes after percutaneous coronary intervention (PCI) than White patients. Inequities in antiplatelet prescribing may contribute to this health disparity. We compared P2Y12inhibitor prescribing by race followingCYP2C19genotyping to guide antiplatelet therapy selection after PCI. Patients from 9 sites that performed clinicalCYP2C19genotyping after PCI were included. Alternative therapy (e.g., prasugrel or ticagrelor) was recommended forCYP2C19no‐function allele carriers, in whom clopidogrel is predicted to be less effective. The primary outcome was choice of P2Y12inhibitor (clopidogrel vs. alternative therapy) based on genotype. Of 3,342 patients included, 2,448 (73%) were White, and 659 (20%) were Black. More Black than White patients had a no‐function allele (34.3% vs. 29.7%,P = 0.024). At hospital discharge following PCI, 44.2% of Black and 44.0% of White no‐function allele carriers were prescribed alternative therapy. At the time of the last follow‐up within 12 months, numerically fewer Black (51.8%) than White (56.7%) no‐function allele carriers were prescribed alternative therapy (P = 0.190). However, the difference was not significant after accounting for other factors associated with P2Y12inhibitor selection (odds ratio 0.79, 95% confidence interval 0.58–1.08). Alternative therapy use did not differ between Black (14.3%) and White (16.7%) patients without a no‐function allele (P = 0.232). Among real‐world patients who receivedCYP2C19testing after PCI, P2Y12inhibitor prescribing rates did not differ between Black and White patients. Our data suggest an absence of racial disparity in genotype‐guided antiplatelet prescribing among patients receivingCYP2C19testing.