Association of VEGF+936 C/T Polymorphism with Susceptibility to Type 2 Diabetic Retinopathy: A Meta-Analysis

The objective of this study is to explore the relationship between the vascular endothelial growth factor (VEGF)+936 C/T polymorphism and the risk of type 2 diabetic retinopathy (T2DR) by a method of meta-analysis. Six online databases were queried to identify studies investigating the VEGF+936 C/T polymorphism that influenced T2DR up to August 2023. The statistical tool of the pooled data was adopted using Stata 15.0 software. The experimental group comprised patients with T2DR, while patients with type 2 diabetes mellitus without retinopathy were considered as the controls. The odds ratio (OR) was utilized as effect size. Eight eligible publications were identified in this review, including 1546 patients with T2DR. The combined results revealed that the VEGF+936 C/T polymorphism was significantly associated with the T2DR risk under the allelic (C/T: OR=0.54, p<0.001), the dominant (CC+CT/TT: OR=0.37, p<0.001), recessive (CC/CT+TT: OR=0.52, p=0.001), homozygous (CC/TT: OR=0.31, p<0.001), and heterozygous (CT/TT: OR=0.55, p=0.005) gene models. No significant correlation was observed regarding the VEGF+936 C/T polymorphism that contributed to the risk of proliferative diabetic retinopathy (PDR) versus non-PDR. In conclusion, the VEGF+936 C/T polymorphism significantly contributed to the T2DR risk. Specifically, at the VEGF+936 C/T locus, the presence of allele C and genotypes CC, CT, and CC+CT were found to be associated with a reduced risk of T2DR.