OBJECTIVE: The angiotensin-converting enzyme (ACE) gene has been implicated in the development of diabetic retinopathy (DR). However, the results have been conflicting. In this study, we performed a meta-analysis to assess the association of insertion/deletion (I/D) polymorphism in the ACE gene with DR in the Chinese population. METHODS: Published literature from PubMed, CNKI, CBM and Wanfang Data were retrieved. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed- or random-effects model. RESULTS: Seventeen studies (1039 cases and 1185 controls) for I/D polymorphism in the ACE gene were identified. The results suggested that I/D polymorphism D allele might increase the risk of DR (DD vs. II: OR = 1.73, 95% CI 1.19-2.51; DD+ID vs. II: OR = 1.41, 95% CI 1.16-1.72; DD vs. ID+II: OR = 1.55, 95% CI 1.13-2.12). Subgroup analyses based on the type of DR showed that the effect size was statistically significant for proliferative DR (PDR) (DD vs. II: OR = 2.67, 95% CI 1.53-4.64; DD+ID vs. II: OR = 1.86, 95% CI 1.18-2.93; DD vs. ID+II: OR = 2.22, 95% CI 1.38-3.55), but not for background DR (BDR) (DD vs. II: OR = 1.38, 95% CI 0.85-2.25; DD+ID vs. II: OR = 1.40, 95% CI 0.98-2.02; DD vs. ID+II: OR = 1.15, 95% CI 0.74-1.79). CONCLUSION: The results indicated that I/D polymorphism in the ACE gene was associated with PDR, but not with BDR in the Chinese population.
OBJECTIVE: The angiotensin-converting enzyme (ACE) gene has been implicated in the development of diabetic retinopathy (DR). However, the results have been conflicting. In this study, we performed a meta-analysis to assess the association of insertion/deletion (I/D) polymorphism in the ACE gene with DR in the Chinese population. METHODS: Published literature from PubMed, CNKI, CBM and Wanfang Data were retrieved. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed- or random-effects model. RESULTS: Seventeen studies (1039 cases and 1185 controls) for I/D polymorphism in the ACE gene were identified. The results suggested that I/D polymorphism D allele might increase the risk of DR (DD vs. II: OR = 1.73, 95% CI 1.19-2.51; DD+ID vs. II: OR = 1.41, 95% CI 1.16-1.72; DD vs. ID+II: OR = 1.55, 95% CI 1.13-2.12). Subgroup analyses based on the type of DR showed that the effect size was statistically significant for proliferative DR (PDR) (DD vs. II: OR = 2.67, 95% CI 1.53-4.64; DD+ID vs. II: OR = 1.86, 95% CI 1.18-2.93; DD vs. ID+II: OR = 2.22, 95% CI 1.38-3.55), but not for background DR (BDR) (DD vs. II: OR = 1.38, 95% CI 0.85-2.25; DD+ID vs. II: OR = 1.40, 95% CI 0.98-2.02; DD vs. ID+II: OR = 1.15, 95% CI 0.74-1.79). CONCLUSION: The results indicated that I/D polymorphism in the ACE gene was associated with PDR, but not with BDR in the Chinese population.