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.