Association between 5,10-Methylenetetrahydrofolate Reductase C677T Gene Polymorphism and Risk of Ischemic Stroke: A Meta-analysis

Background Hyperhomocysteinemia, a condition that is strongly determined by dietary intake of B vitamins, has been suggested to be an independent risk factor for ischemic stroke (IS). To test this hypothesis, we performed a meta-analysis to investigate the associations between 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, which plays a critical role in modulating plasma homocysteine concentrations, and IS risk. Materials and Methods We searched case–control studies on the association between MTHFR C677T genetic polymorphism and susceptibility to IS through PubMed, Embase, and Medline databases from January 2000 up to October 2014. The random-effects model was employed because moderate heterogeneity across studies was observed, as assessed by I 2 statistic. Publication bias was estimated using funnel plot and Egger's regression test. Results A total of 22 case–control studies were included in the current meta-analysis. Significant associations between MTHFR C677T genetic polymorphism and IS were found under the dominant model (pooled odds ratio [OR] = 1.40, 95% confidence interval [CI]: 1.24-1.57), the recessive model (pooled OR = 1.37, 95% CI: 1.16-1.61), and the allele model (pooled OR = 1.29, 95% CI: 1.18-1.42). Conclusions The meta-analysis suggests that MTHFR C677T genetic polymorphism is significantly associated with susceptibility to IS, which provides evidence supporting hyperhomocysteinemia as a risk factor for stroke.