Introduction: The effect of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on risk of diabetic nephropathy (DN) is still conflicting. The present meta-analysis was performed to evaluate the overall risk of this polymorphism associated with DN in different groups.
Materials and methods: A predefined search was performed on 14,108 DN cases and 12,472 controls from 63 published studies by searching electronic databases and reference lists of relevant articles.
Results: In this meta-analysis, we found a significant association between the ACE I/D polymorphism and the risk of DN for all genetic models (ID versus II: odds ratio [OR] = 1.12, 95% confidence interval [CI] 1.02-1.24; DD versus II: OR = 1.27, 95% CI 1.13-1.44; allele contrast: OR = 1.15, 95% CI 1.08-1.23; dominant model: OR = 1.18, 95% CI 1.07-1.31; and recessive model: OR = 1.18, 95% CI 1.08-1.30, respectively). In stratified analysis by ethnicity and DM type, we further found that the Asian group with type 2 diabetes mellitus (T2DM) showed a significant association for all genetic models (ID versus II: OR = 1.25, 95% CI 1.07-1.47; DD versus II: OR = 1.57, 95% CI 1.24-1.98; allele contrast: OR = 1.30, 95% CI 1.15-1.46; dominant model: OR = 1.37, 95% CI 1.10-1.69; and recessive model: OR = 1.34, 95% CI 1.15-1.56, respectively).
Conclusions: Our study suggested that the ACE I/D polymorphism may contribute to DN development, especially in the Asian group with T2DM.