Associations between erythropoietin polymorphisms and risk of diabetic microvascular complications

We conducted a meta-analysis to evaluate the relationship between erythropoietin (EPO) polymorphisms and diabetic microvascular complications. We searched the PubMed, Embase, Cochrane library, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure databases for appropriate studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the associations. Ultimately, eight studies consisting of 2,861 cases and 2,136 controls were identified and included in our meta-analysis. Results with our genotype model indicated an association between rs1617640 polymorphisms and diabetic microvascular complications (TT vs. GG: OR = 1.544, 95% CI = 1.089-2.189, P = 0.015). No clear associations between the rs1617640 and rs507392 polymorphisms and diabetic retinopathy were observed. By contrast, rs551238 polymorphisms were associated with increased diabetic retinopathy risk (allele model: OR = 0.774, 95% CI = 0.658-0.911, P = 0.002; genotype model: AC vs. CC: OR = 0.598, 95% CI = 0.402-0.890, P = 0.011; dominant model: OR = 0.561, 95% CI = 0.385-0.817, P = 0.003; recessive model: OR = 0.791, 95% CI = 0.643-0.973, P = 0.026). These results indicate that EPO polymorphisms are a risk factor for diabetic microvascular complications.