Vascular endothelial growth factor polymorphisms and risk of Alzheimer's disease: a meta-analysis.

There were conflicting results about whether promoter polymorphisms (-2578C/A, -1154G/A) of vascular endothelial growth factor (VEGF) gene is a risk factor of Alzheimer's disease (AD). To determine the relationship between them, a meta-analysis is needed urgently. We searched all the reports about VEGF promoter polymorphisms (-2578C/A, -1154G/A) and AD risk from PubMed, Web of Science, Cochrane Collaboration and Google Scholar database for the period up to 1 August, 2012. A total of 7 studies were included in this meta-analysis. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated applying fixed or random effects models. There was no significant association between VEGF -2578C/A polymorphisms and AD risk in all gene models (OR=1.08, 95% CI=0.94-1.23 for A vs. C; OR=1.19, 95% CI=0.89-1.59 for AA vs. CC; OR=1.15, 95% CI=0.91-1.45 for AA vs. CC+CA; OR=1.11, 95% CI=0.98-1.25 for AA+CA vs. CC). Similar results were provided in subgroup analysis by ethnicity. For the VEGF -1154G/A polymorphisms, lack of an association was also found (A vs. G: OR=0.89, 95% CI=0.79-1.01; AA vs. GG: OR=0.82, 95% CI=0.62-1.08; AA vs. GA+GG: OR=0.89, 95% CI=0.68-1.16; AA+AG vs. GG: OR=0.85, 95% CI=0.72-1.00). Conclusively, the result of this meta-analysis suggested that VEGF promoter polymorphisms (-2578C/A, -1154G/A) might not contribute to the susceptibility of AD. Crown