The efficacy of Chinese herbal drugs for adults with angina pectoris: Bayesian network meta-analysis of 331 RCTs involving 36,467 individuals

Hundreds of randomized controlled trials (RCT) on Chinese herbal drugs (CHDs) including Shexiang baoxin pill (BXP), compound Danshen dripping pill (DSP), compound Danshen tablet (DST), Suxiao jiuxin pill (JXP), Naoxintong capsule (NXT), Tongxinluo capsule (TXL), and Di'ao xinxuekang capsule (XXK) and conventional chemical drugs, such as isosorbide dinitrate (ISDN), for angina pectoris are available but have not been evaluated by a PRISMA-compliant network meta-analysis (NMA). This study aimed to compare the efficacy of nine anti-anginal drugs through NMA on RCTs. RCTs of drug treatment for adult patients with angina pectoris for symptomatic and electrocardiography improvements were searched. Odds ratios and 95% credible intervals were computed to measure effect sizes. RCT quality was evaluated with the Cochrane risk of bias tool. Evidential synthesis was performed with Bayesian NMA. Essential analyses including subgroup and sensitivity analysis, meta-regression analysis, publication bias analysis, and ranking analysis were conducted to assess the robustness of efficacies. Evidence strength was assessed with the GRADE approach. A total of 331 RCTs with 36,467 participants were selected and the overall quality of all included RCTs was low. Overall efficacy estimates from different approaches of evidential synthesis found that BXP, TXL, and DSP were more efficacious than DST and ISDN. Adequate essential analyses indicated consistent efficacy estimates, insignificant publication bias, and corroborative ranking results. The overall GRADE evidence strength was low. This comprehensive Bayesian NMA found BXP, TXL, and DSP to be the top three candidates among the seven tested CHDs for treating adult patients suffering from angina pectoris. However, the quality and the evidence strengths of RCTs were low. Further high-quality RCTs with more outcome measures and their NMAs are warranted. PROSPERO CRD42014007035.