Endothelial NO Synthase Gene Polymorphisms and Risk of Ischemic Stroke in Asian Population: A Meta-Analysis

Background:The association between polymorphism 4b/a, T-786C and G894T in endothelial NO synthase gene (eNOS) and ischemic stroke (IS) remains controversial in Asian. A meta-analysis was performed to better clarify the association between eNOS gene and IS risk. Methods: Based on the search of PubMed, Web of Science (ISI), CNKI (National Knowledge Infrastructure), Wan Fang Med Online and CBM (Chinese Biology Medical Literature Database) databases, all eligible case-control or cohort studies were identified. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) from fixed and random effect models were calculated. Heterogeneity among studies was evaluated using the I-2. Meta-regression was used to explore the potential sources of between-study heterogeneity. Begg's test was used to estimate publication bias. Results:Our study included 27 articles, contained 28 independent case-control studies, involved a total of 3,742 cases and 3,691 controls about 4b/a, 1,800 cases and 1,751 controls about T-786C and 2,747 cases and 2,872 controls about G894T. A significant association of 4a allele with increased risk of IS was found in dominant (FEM: OR= 1.498, 95% CI = 1.329-1.689), recessive (FEM: OR 2.132, 95% CI = 1.383-3.286) and codominant (REM: OR = 1.456, 95% CI = 1.235-1.716) models. For T-786C and G894T, there were significant associations with dominant and codominant genetic models, but not with recessive genetic model. Conclusions:The meta-analysis indicated that eNOS gene 4b/a, T-786C, G894T polymorphism might be associated with IS.