To systematically review the efficacy and safety of Buzhong Yiqi Decoction in the treatment of stable chronic obstructive pulmonary disease(COPD) at the stable stage. Three English databases and four Chinese databases were systematically searched from the database establishment to August 1, 2020. Randomized controlled trials(RCTs) were screened according to the pre-determined inclusion and exclusion criteria, and then the data were extracted. Methodological quality of the included studies was assessed based on Cochrane bias risk tool, and RevMan 5.3 was used for data analysis. A total of 389 articles were retrieved and finally 18 RCTs were included in this study, involving 1 566 patients, and the overall quality of the included studies was not high. Meta-analysis showed that, in terms of improving 6-minute walk distance(6 MWD), and delaying the decline of forced expiratory volume in one second(FEV_1) or its % in the expected value as well as the decline in ratio of FEV_1 to forced vital capacity(FVC), Buzhong Yiqi Decoction alone or in combination with conventional Western medicine was superior to conventional therapy Western medicine alone. Subgroup analysis showed that, in terms of reducing traditional Chinese medicine symptom scores, Buzhong Yiqi Decoction combined with conventional treatment was superior to conventional treatment. In terms of reducing the grade of modified medical research council(mMRC), Buzhong Yiqi Decoction combined with conventional treatment was superior to conventional treatment. In terms of improving 6 MWD, Buzhong Yiqi Decoction combined with conventional treatment or Tiotropium Bromide Powder for Inhalation was superior to conventional treatment alone or Tiotropium Bromide Powder for Inhalation alone. In terms of delaying the decline of FEV_1 or its % in the expected value, Buzhong Yiqi Decoction combined with conventional treatment or Salmeterol Xinafoate and Fluticasone Propionate Powder for Inhalation or Tiotropium Bromide Powder for Inhalation was superior to conventional treatment or Salmeterol Xinafoate and Fluticasone Propionate Powder for Inhalation or Tiotropium Bromide Powder for Inhalation alone, and Buzhong Yiqi Decoction alone was superior to Theophylline alone. In terms of delaying the decline in FEV_1/FVC, Buzhong Yiqi Decoction combined with conventional treatment was superior to conventional treatment, and Buzhong Yiqi Decoction alone was superior to Theophylline alone. Meta-analysis of other outcome measures was not available and no conclusion can be drawn due to the inclusion of only one study. As some studies did not mention the adverse reactions, no safety comments can be made for Buzhong Yiqi Decoction alone or combined with conventional Western medicine. Due to the limitations of the quality and quantity of included studies, the conclusions of this research should be treated with caution. The efficacy of Buzhong Yiqi Decoction for stable COPD still needs more high-quality studies for confirmation, and its safety needs to be further verified.
Keywords: Buzhong Yiqi Decoction; Meta-analysis; efficacy; safety; stable chronic obstructive pulmonary disease; systematic review.