Objectives Genetic polymorphism of human myeloperoxidase (MPO) -463G/A has been implicated to alter the risk of coronary artery disease (CAD), but the results are controversial. To improve the reliability of the conflicting results, we conducted a meta-analysis of studies relating the MPO -463G/A polymorphism with the risk of CAD.
Methods Two investigators independently searched the MEDLINE, EMBASE and Cochrane Library up to June, 2012. Summary odds ratios (OR) and 95% confidence interval (CI) for the MPO -463G/A polymorphism and CAD risk were calculated, and potential sources of heterogeneity and publication bias were explored. Statistical analysis was performed with the software program of Stata 9.0.
Results 5 case-control studies were finally identified for analyses, involving 1938 cases with CAD and 1990 controls. We found that the MPO -463G/A polymorphism has no significant association with overall CAD risk (G/G vs A/A: OR = 0.595, 95%CI = 0.298-1.188, P = 0.141; G/G vs G/A + A/A: OR = 0.886, 95%CI = 0.779-1.008, P = 0.066; G/G + G/A vs A/A: OR = 0.611, 95%CI = 0.334-1.119, P = 0.111; OR = 0.886, 95%CI = 0.779-1.008, P = 0.066; G vs A: OR = 0.843, 95%CI = 0.675-1.053, P = 0.133). The heterogeneity test showed that there were significant differences between individual studies in additive, recessive and allelic genetic model (P = 0.008, P = 0.021, P = 0.019, respectively), further analyses revealed that age and sex possibly account for the heterogeneity.
Conclusions Our meta-analysis demonstrated the evidence that there was no significant association between the MPO -463G/A polymorphism and the risk of CAD, larger and well-designed multicentre studies are needed to confirm our results.