Combination therapy an ACE inhibitor and an angiotensin receptor blocker for IgA nephropathy: a meta-analysis

OBJECTIVE: The pathogenesis of IgA nephropathy (IgAN) is still unknown. Combination therapy with angiotensin-converting enzyme inhibitors (ACEIs) plus angiotensin receptor blockers (ARBs) might provide more benefits to IgAN patients. We conducted a systematic review to assess the efficacy of combination therapy for IgAN. METHODS: The MEDLINE, EMBASE, the Cochrane Library and article reference lists were searched for randomised clinical trials (RCTs) which involved combination therapy ACEI plus ARB in only one arm. A meta-analysis was performed on the outcomes of proteinuria and renal function in IgAN patients. RESULTS: Six RCTs involving 109 patients were included in the review. Combined treatment with ACEI plus ARB was more effective than with ACEI/ARB alone for reducing daily proteinuria. This did not translate into an improvement in GFR. Patients receiving ACEI plus ARB therapy did not have an increased risk of hyperkalemia. CONCLUSIONS: The current cumulative evidence suggests that combination therapy ACEI plus ARB may provide more benefits to IgAN patients for reducing daily proteinuria. Long-term effects of these agents on renal outcomes, and safety need to be established.