To perform a meta-analysis of Russian prospective studies comparing the pharmacogenetic versus conventional warfarin dosing procedures.
Publications were sought in the PubMed and eLibrary through September 30, 2013. Seven prospective studies comparing the pharmacogenetic method of warfarin dosing with consideration for CYP2C9, VKORC1, and CYP4F2 gene polymorphisms with the conventional one were selected. The number of minor and major bleedings and hypocoagulation episodes was taken into account. The meta-analysis was performed using MIX Pro 2.0.
Six studies compared the number of bleedings in experimental and control groups. Analysis of statistical heterogeneity showed that extraneous factors did not influence the results of meta-analysis. The pharmacogenetic approach decreases the risk of bleeding. The pooled odds ratio (OR) was significant for minor (OR = 0.49; 95% confidence interval (CI), 0.31 to 0.78; p = 0.002), major (OR = 0.07; 95% CI, 0.008 to 0.54; p = 0.01) and both minor and major bleedings (OR = 0.49; 95% CI, 0.31 to 0.78; p = 0.002). Six studies estimated the number of hypocoagulation cases. There was no evidence for statistical heterogeneity (Q-test p = 0.13; I2 = 40%). Four studies showed a group difference in the number of hypocoagulation cases (p