Efficacy and Safety of Salvia miltiorrhiza for Treating Chronic Kidney Diseases: A Systematic Review and Meta-Analysis

OBJECTIVE: This meta-analysis evaluated the effects and potential harms of Salvia miltiorrhiza or its extracts Salvianolate and Tanshinone for the treatment of population with a chronic kidney disease (CKD). METHODS: We searched for the randomized clinical trials (RCTs) through databases including the Cochrane Library, PubMed, Embase, Web of Science, Current Controlled Trials, China National Knowledge Infrastructure (CNKI), Wanfang Data Knowledge Service Platform (Wanfang Data), China Biology Medicine Disc (SinoMed), and Chinese Clinical Trial Registry (ChiCTR). Meta-analysis was performed with STATA 16 software after data extraction. The risk of bias was assessed with the Cochrane risk-of-bias tool (RoB 2.0), and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework was employed to evaluate the quality of evidence. RESULT: A total of 32 studies were included involving 2264 participants. Compared to the control group, the treatment group significantly decreased serum creatinine (SCr) (SMD −0.60, 95% CI −0.79 to −0.41, P < 0.0001), blood urea nitrogen (BUN) (SMD −0.66, 95% CI −0.81 to −0.50, P < 0.0001), Cystatin C (CysC) (SMD −5.16, 95% CI −14.84 to 4.53, P=0.297), 24 hour urine protein (24 h UPE) (SMD −0.70, 95% CI −1.21 to −0.19, P=0.008), time to initiation of dialysis (Log RR 0.43, 95% CI 0.23 to 0.81, P=0.0089), serum total cholesterol (TC) (SMD −0.53, 95% CI −0.88 to −0.17, P=0.0042, P=0.0035), plasma fibrinogen (FIB) (SMD −0.79, 95% CI −1.12 to −0.46, P < 0.0001), C-reactive protein (CRP) (SMD −0.56, 95% CI −0.93 to −0.19, P=0.0029); increased creatinine clearance (Ccr) (SMD 0.92, 95% CI 0.43 to 1.41, P=0.0002), glomerular filtration rate (GFR) (SMD 0.56, 95% CI 0.30 to 0.83, P < 0.001), effective rate (Log RR 0.30, 95% CI 0.23 to 0.37, P < 0.0001), and hemoglobin (Hb) (SMD 0.42, 95% CI 0.13 to 0.71, P=0.0042). Moreover, the incidences of adverse effects were similar between the two groups. CONCLUSIONS: Salvia miltiorrhiza or its extracts Salvianolate and Tanshinone, as a complementary therapy to conventional medicine, presents potential impacts to improve kidney functions and delay the progression of CKD without obvious adverse effects. However, the certainty of the evidence and the risk of bias are suboptimal and further clinical studies are still required to determine the underlying effects.