Efficacy and safety of Flos Abelmoschus manihot (Malvaceae) on type 2 diabetic nephropathy: A systematic review.

Objective: To evaluate the efficacy and safety of Flos Abelmoschus manihot (Malvaceae) on type 2 diabetic nephropathy (DN).

Methods: The Cochrane Library, PubMed/MEDLINE, Excerpta Medical Database, Chinese electronic literature databases, and the references of relevant articles were searched in March 2012 for randomized controlled trials (RCTs) that reported the effects of Flos A. manihot on type 2 DN patients with overt but subnephrotic-range proteinuria (500-3,500 mg/24 h). The quality of trials was evaluated using the Cochrane-recommended method. The results were summarized as risk ratios (RRs) for dichotomous outcomes or mean differences (MDs) for continuous outcomes.

Results: Seven trials (531 patients) were included. Flos A. manihot significantly decreased proteinuria [MD -317.32 mg/24 h, 95% confidence interval (CI) [-470.48, -164.17],P<0.01]. After excluding a trial that only included patients with well-preserved renal function, Flos A. manihot was associated with a significant decrease in serum creatinine (MD -11.99 μmol/L, 95% CI [-16.95, -7.04],P<0.01). Serious adverse events were not observed. The most common adverse event was mild to moderate gastrointestinal discomfort; however, patients receiving this herb did not have an increased risk for tolerated gastrointestinal discomfort (RR 1.48, 95% CI [0.39, 5.68],P=0.57).

Conclusions: Flos A. manihot may be considered as an important adjunctive therapy with the first-line and indispensable therapeutic strategies for type 2 DN. High-quality RCTs are urgently needed to confirm the effect of Flos A. manihot on definite endpoints such as end-stage renal disease.