Cytochrome P450 CYP 2C19*2 Associated with Adverse 1-Year Cardiovascular Events in Patients with Acute Coronary Syndrome

BACKGROUND The cytochrome P450 (CYP450) 2C19 681 genotypes affect the antiplatelet activity of clopidogrel. We investigated the correlation of CYP 2C19 681G > A mutation with clopidogrel resistance (CR). Additionally, we studied the effect of CR on clinical prognosis of patients with acute coronary syndrome (ACS). METHODS One hundred ten ACS patients undergoing percutaneous coronary intervention, who were followed-up for 1 year, were included in the study. The patients were co-administered aspirin 100 mg/d and clopidogrel 75mg/d following a loading dose of 300 mg. CR was assessed on the basis of polymorphism observed in the CYP2C19 subgroup. RESULTS Patients in GG genotype group exhibited greater inhibition of platelet aggregation than patients in GA and AA genotype groups (16.2 ± 10.1%; 10.2 ± 9.9%; 8.0 ± 5.9%, respectively, p < 0.01). CYP2C19 681GG genotype group was associated with lower CR than CYP2C19 681A allele (GA + AA) group (9/59 vs. (12+5)/51; p = 0.009). Over a follow-up of 12 months, the incidence of recurrent angina, acute myocardial infarction, and intra-stent thrombosis in CYP2C19 681 GG carriers was significantly lower than that in CYP2C19 681A allele (GA + AA) group (2/59 vs. 8/51, 1/59 vs. 6/51, 0 vs. 4/51, respectively, p < 0.05). CONCLUSION CYP 2C19*2 is associated with reduced clopidogrel antiplatelet activity and might be an important marker for poor prognosis of ACS.