Objective: To perform a meta-analysis on studies evaluating the effect of angiotensin-converting enzyme (ACE) inhibitors on diabetic nephropathy in patients with type 2 diabetes mellitus.
Methods: A computerized literature search was conducted for articles of studies comparing ACE inhibitors with a control in patients with diabetes, in which measurement of albuminuria or proteinuria was an outcome. Each article was abstracted by two of the authors. Data from the articles were presented as geometric or arithmetic means. The data were summarized separately by using standard techniques for meta-analysis.
Main results: Statistically significant reductions in albuminuria were observed regardless of whether data were described with geometric or arithmetic means. Both were associated with significant heterogeneity. When studies reporting geometric means were stratified and analyzed, the heterogeneity was lost and statistically significant reductions in albuminuria were observed. The same procedure was repeated for studies reporting arithmetic means, but heterogeneity remained.
Conclusion: The ACE inhibitors produce statistically significant reductions in albuminuria associated with significant heterogeneity of effect. Stratification reduces the heterogeneity and supports treatment with ACE inhibitors to reduce the progression of nephropathy in patients with type 2 diabetes mellitus.