An updated meta-analysis: Apolipoprotein E genotypes and risk of primary open-angle glaucoma

PURPOSE: To study the association of apolipoprotein E (APOE) polymorphisms and primary open-angle glaucoma (POAG). METHODS: After a systematic literature search, all relevant studies evaluating the association between APOE polymorphisms and POAG were included. All statistical tests were calculated with Stata 11.0. RESULTS: Twelve independent studies on the APOE gene (1,971 cases, 1,756 controls) and POAG were included. A significant association between the APOE gene and POAG was found in the genetic model of ε4/ε4 versus ε3/ε3 (odds ratio [OR] = 2.09, 95% confidence interval [CI] = 1.12–3.88, p = 0.02). However, no association was detected in the models of ε2/ε2 versus ε3/ε3, ε2/ε3 versus ε3/ε3, ε2/ε4 versus ε3/ε3, ε3/ε4 versus ε3/ε3, allele ε2 versus allele ε3, and allele ε4 versus allele ε3. Subgroup analyses showed that a statistically significant association between the APOE gene and the risk of POAG existed in the genetic model of ε4/ε4 versus ε3/ε3 in Asians (OR = 3.55, 95% CI = 1.06–11.87, p = 0.04). No association was identified between the APOE gene and the risk of POAG in Caucasians. CONCLUSIONS: The present meta-analysis indicated that the ε4/ε4 genotype is associated with increased risk of POAG in Asians.