Adverse events in cardiovascular disease patients taking clopidogrel: impact of CYP2C19 genotype polymorphisms

Abstract Background: Clopidogrel combined with aspirin in antiplatelet therapy is the first-line clinical regimen for cardiovascular diseases. The CYP2C19 gene influences the absorption and metabolism of clopidogrel and its polymorphisms affect antiplatelet therapy drug efficacy, which may lead to adverse events including stent thrombosis and haemorrhage. The main objective of this study was to explore the impact of CYP2C19 polymorphisms on adverse events in cardiovascular disease patients.Methods:We recruited 350 patients taking clopidogrel and performed CYP2C19 genotype testing. Adverse event information was collected through telephone follow-up. According to CYP2C19 genotype results, patients were divided into three groups: poor metabolism (PM) group, extensive metabolism (EM) group and intermediate metabolism (IM) group. The number of adverse events was compared between the three groups using the chi-squared test and the onset time of adverse events was analysed using the log-rank test. The main factors affecting adverse events were analysed using binary logistic analysis.Results: In total, 326 patients were included in the analysis: 143 patients were in the EM group, 129 patients were in the IM group and 54 patients were in the PM group. In this cohort, 127 adverse events were noted, which occurred in 88 patients. There was no significant difference in the occurrence of adverse events between the EM group and PM group (P=0.185). The median survival times of adverse events in the EM, IM and PM groups were 112 days, 137.5 days and 169 days, respectively, with no significant differences between the three groups (P=0.8713).Conclusion:We found that CYP2C19 polymorphisms were not necessarily associated with adverse events in patients with cardiovascular diseases taking clopidogrel. Rather, the main factors influencing the occurrence of adverse events were concomitant diseases such as hypertension, diabetes and hyperlipidaemia.