Background: Polymorphisms in the cytochrome P450 2C19 (CYP2C19) gene have been reported to be associated with coronary heart disease (CHD), but the results were not consistently analyzed among different patient groups. To derive a more precise estimation of these associations, we will conduct a meta-analysis to investigate the polymorphisms of CYP2C19 in all published studies.
Methods: Electronic databases (Google Scholar, ISI Web of Science, Pubmed, Embase, China National Knowledge Infrastructure, Wanfang, and China Biological Medicine) will be used to search clinical case-control or cohort studies about CYP2C19 polymorphism and CHD published until November 2020. Two reviewers will independently select the study, extract the data, and evaluate the quality of the study. Odds ratios with 95% confidence interval will be used to evaluate the strength of the association between the CYP2C19 polymorphism and CHD susceptibility under 4 genetic models. Subgroup analysis will be conducted by different ethnicity and genotyping method. Sensitivity analysis will be performed via sequentially omitting each of the included studies 1 at a time. Begg funnel plots and Egger test will be used to examine the potential publication bias. All the statistical analyses will be performed using Review Manager 5.3 and Stata 12.0.
Results: This study will provide a better understanding of the association between CYP2C19 polymorphisms and coronary heart disease risk.
Conclusion: The publication of this protocol will minimize the possibility of bias due to post hoc changes to the analysis protocol, thus helping to obtain reliable evidence.
Osf registration number: DOI 10.17605/OSF.IO/R7U93.