IDDF2021-ABS-0052 Chinese herbal medicine for functional dyspepsia: network meta-analysis of placebo-controlled randomised trials

BackgroundFunctional dyspepsia (FD) is a common functional gastrointestinal disorder, having a prevalence of 10–40% in Western countries and 5–30% in Asia. Conventional treatments for FD are limited and associated with bothersome adverse events. Chinese herbal medicine (CHM) use is prevalent despite unclear comparative effectiveness among different formulae. This network meta-analysis (NMA) aimed to evaluate the comparative effectiveness of CHM formulae for FD against placebo.MethodsThree international (MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials) and four Chinese (Wanfang Data, China National Knowledge Infrastructure, SinoMed, and Index to Taiwan Periodical Literature System) databases were searched for randomised controlled trials (RCTs) on CHM versus placebo. The risk of bias among RCTs was assessed using Cochrane Risk-of-Bias Tool 2. Data from RCTs were extracted for random-effect pairwise meta-analyses. Random-effect NMAs were performed to evaluate the comparative effectiveness of CHM formulae. GRADE partially contextualised framework was adopted to facilitate NMA result interpretation.ResultsTwelve different CHM formulae were identified from fifteen RCTs of mediocre quality. At 8-week follow-up, pairwise meta-analyses indicated that CHM was superior to placebo in alleviating global symptoms (pooled risk difference (RD): 0.20; 95% confidence interval (CI): 0.11–0.29), with effect size larger than the minimally clinically important difference of 0.20 RD. Sensitivity analysis showed no significant impact on results attributable to the risk of bias. NMAs demonstrated that Xiao Yao Pill and Modified Ban Xia Xie Xin Decoction probably have a large beneficial effect on alleviating global symptoms (RD: 0.37; 95% CI: 0.03–0.99) and postprandial fullness (standardised mean difference: -0.93; 95% credible interval: -1.61– -0.06), respectively. No serious adverse events were reported.ConclusionsXiao Yao Pill and Modified Ban Xia Xie Xin Decoction may be considered as an alternative among patients unresponsive to conventional treatments. The comparative effectiveness of these two formulae should be evaluated in future head-to-head confirmatory trials.