P2Y12 Polymorphisms and the Risk of Adverse Clinical Events in Patients Treated with Clopidogrel: A Meta-Analysis

Background and study aim: Some studies have reported an association between P2Y12 gene polymorphisms and clopidogrel adverse outcomes with inconsistent results. We aimed to explore the relationship between P2Y12 polymorphisms and the risk of adverse clinical events in patients treated with clopidogrel through a meta-analysis.

Methods: A systematic search of PubMed, Web of Science and the Cochrane Library was conducted. Retrieved articles were comprehensively reviewed and eligible studies were included, and the relevant data was extracted for this meta-analysis. All statistical tests were performed by the Review Manager 5.3 software.

Results: A total of 14 studies involving 8,698 patients were included. In the Han Chinese population, ischemic events were associated with P2Y12 T744C polymorphism in the CC vs TT+CT genetic model (OR=3.32, 95%CI=1.62-6.82, P=0.001), and the events were associated with P2Y12 C34T polymorphism in the TT+TC vs CC genetic model (OR=1.70, 95%CI=1.22-2.36, P=0.002). However, ischemic events were not related to P2Y12 G52T polymorphism (TT+TG vs GG: OR=1.13, 95%CI=0.76-1.68, P=0.56; TT vs GG+TG: OR=2.02, 95%CI=0.65-6.28, P=0.22). The associations between the P2Y12 polymorphism and ischemic events were not significant in T744C, G52T and C34T genotype for another subgroup of the Caucasian population (P>0.05). Only two studies referring to bleeding events were included in this analysis of C34T polymorphism, and no significant association was found (TT+TC vs CC: OR=1.07, 95%CI=0.37-3.15, P=0.90).

Conclusions: In the Caucasian population, P2Y12 gene polymorphisms are not associated with clinical events. However, in the Chinese Han population, P2Y12 T744C and C34T polymorphisms are significantly associated with adverse clinical events.