Systematic review and meta-analysis of 16 randomized clinical trials of radix astragali and its prescriptions for diabetic retinopathy.

Objective. To evaluate the efficacy and safety of radix astragali and its prescriptions for diabetic retinopathy. Methods. A computer-based online and manual search was conducted for randomized controlled trials addressing radix astragali and its prescriptions for diabetic retinopathy. Results. 16 RCTs involving 977 subjects and 1586 eyes were identified. Meta-analysis indicated that the effect of radix astragali and its prescriptions in improving visual acuity and fundus manifestations, lowering FBG, TG, plasma viscosity, and RAI, was superior to that of control group (WMD or OR 0.20, 0.27, -0.26, -0.36, -0.93, -1.27; 95% CI [0.09, 0.30], [0.17, 0.40], [-0.51, 0.00], [-0.60, -0.12], [-1.67, -0.20], [-2.35, -0.19]; P < 0.05, resp.). In contrary, the efficacy of radix astragali and its prescriptions was not superior to those of control group in descending HbA1C and TC with WMD 0.45, -0.96 and 95% CI [-1.00, 1.90], [-2.19, 0.27], P > 0.05, respectively. GRADE software suggested that the studies were of low methodological quality. Conclusion. Radix astragali and its prescriptions were superior to other treatments for diabetic retinopathy in terms of improving visual acuity and fundus manifestations, reducing FBG, TG, RAI, and plasma viscosity. The evaluated studies were of low methodological quality, indicating that the previous findings should be read with care.