ACEI/ARB therapy for IgA nephropathy: a meta analysis of randomised controlled trials

BACKGROUND: Published reports examining the efficacy of RAS blockers: angiotensin converting-enzyme inhibitor (ACEI) and angiotensin II receptor blocker (ARB) agents for preserving renal function in IgA nephropathy (IgAN) have yielded conflicting results. To evaluate systematically the effects of ACEI/ARB agents on IgAN, we conducted a meta analysis of published randomised controlled trials (RCTs). METHODS: MEDLINE, EMBASE, the Cochrane Library and article reference lists were searched for RCTs that compared ACEI/ARB with placebo and any other antihypertensive agents or non-immunosuppressive agents for treating IgAN. The quality of the studies was evaluated with the method of intention to treat analysis and allocation concealment, as well as with the Jadad method. Meta analyses were performed on the outcomes of proteinuria and renal function in patients with IgAN. RESULTS: Eleven RCTs involving 585 patients were included in the review. Seven trials used placebo/no treatment as controls. Four trials used other antihypertensive agents as controls. Overall, ACEI/ARB agents had statistically significant effects on protecting renal function(p < 0.00001) and reduction of proteinuria (p < 0.00001) when compared with control group. Tests for heterogeneity showed no difference in effect among the studies. Systolic and diastolic blood pressure, glomerular filtration rate (GFR), age, did not influence treatment response. ACEI/ARB agents were well tolerated. CONCLUSIONS: The current cumulative evidence suggests that ACEI/ARB agents had statistically significant effects on protecting renal function and reduction of proteinuria in patients with IgAN when compared with control groups. ACEI/ ARB agents are a promising medication and should be investigated further.