Efficacy and safety of angiotensin-converting enzyme inhibitors/angiotensin receptor blocker therapy for IgA nephropathy: A meta-analysis of randomized controlled trials.

BACKGROUND: Published reports evaluating whether angiotensin-converting enzyme inhibitors/angiotensin receptor blocker (ACEI/ARB) therapy could bring improvements to the prognosis of immunoglobulin A nephropathy (IgAN) have yielded confusing results, which entails a systematic review of those reports. In this study, we summarized currently available evidence from randomized controlled trials (RCTs) that evaluated the effect of ACEI/ARB therapy of IgAN.

METHODS: PubMed, International comprehensive biomedical information bibliographic database produced by the National Library of Medicine (MEDLINE), Excerpt Medica Database (EMBASE), and Cochrane Library and article reference lists were searched for RCTs that compared ACEI/ARB with placebo and any other nonimmunosuppressive agents except RAAS agents for treating IgAN. The quality of the studies was evaluated with the performance of explicit eligibility criteria and the revised Jadad scale. Meta-analyses were completed on the outcomes of proteinuria, serum creatinine (SCr), blood pressure and glomerular filtration rate (GFR) in patients with IgAN.

RESULTS: Five RCTs involving 295 patients were included in this review. ACEI/ARB agents had statistically significant effects on reduction proteinuria (standardized mean differences [SMD], -0.46; 95% confidence interval [CI], -0.64 to -0.27; P < 0.00001; heterogeneity I 2  = 35%; P = 0.20) and blood pressure, but no significant difference was found on SCr (SMD, -3.51; 95% CI, -16.55 to 9.54; P = 0.60; heterogeneity I 2  = 0%; P = 0.74) and GFR (SMD, 2.59; 95% CI, -7.14 to 12.33; P = 0.60; heterogeneity I 2  = 57%; P = 0.10).

CONCLUSION: ACEI/ARB agents had statistically significant effects on reducing proteinuria. As proteinuria is a major pathology of IgAN, which was significantly improved by ACEI/ARB, we proposed that ACEI/ARB agents were a promising therapy. Because the studies under review did not perform blind method, used a variety of doses and types of ACEI/ARB agents and lacked follow-up to evaluate the long-term effect of the agents on IgAN patients.