Efficacy of herbal medicine (Gegen Qinlian Decoction) on ulcerative colitis: A systematic review of randomized controlled trials

BACKGROUND: This systematic review aims to evaluate the efficacy of Gegen Qinlian Decoction (GQD) for ulcerative colitis (UC). METHODS: PubMed, EMBASE, Springer LINK, Cochrane Library, the China National Knowledge Infrastructure, Chongqing Weipu Database for Chinese Technical Periodicals, Wan-fang Database, and Chinese Biomedicine Database were searched from their inception to December 2018 for randomized controlled trials comparing the use of GQD alone or in combination with western medicine (WM) with that of WM therapies for UC. Outcomes on the therapy's effectiveness rate, ulcerative colitis endoscopic index of severity (UCEIS), recurrence rate, and adverse events were extracted and analyzed by Review Manager 5.3 software. Meta-analysis was combined with fixed or random-effects model, and risk ratios (RR) and 95% confidence intervals (CI) were calculated for all outcomes. Two researchers independently reviewed each trial to determine its inclusion. The Cochrane risk of bias assessment tool was used for quality assessment. RESULTS: We included 22 trials involving 2028 patients with UC. When compared with WM therapy, GQD significantly improved the clinical effectiveness (n = 591, RR = 1.21, 95% CI: 1.12–1.31, P < .00001) and recurrence rate (n = 94, RR = 0.23, 95% CI: 0.10–0.54, P = .0006). GQD plus WM was more effective in improving the clinical effectiveness (n = 1337, RR = 1.21, 95% CI: 1.16–1.27, P < .00001), and decreasing UCEIS scores (n = 384, mean difference = −0.63, 95% CI: −1.26–−0.01, P = .05), recurrence rate (n = 179, RR = 0.18, 95% CI: 0.06–0.61, P = .006). In addition, the adverse events for GQD (n = 238, RR = 0.20, 95% CI: 0.02–1.68, P = .14) and GQD plus WM (n = 427, RR = 0.37, 95% CI: 0.15–0.90, P = .03) was significantly lower than that for WM alone. Noted adverse events primarily included gastrointestinal symptoms, headache, dizziness, and leukocytopenia. CONCLUSIONS: This meta-analysis shows that GQD used alone or in combination with WM might have potential benefits in curing UC. However, there is no sufficient evidence to draw definite conclusion supporting the effect of GQD for UC due to poor methodological quality of the included trials. More rigorously designed investigations and studies with large sample sizes should be conducted to establish clinical evidence further.