Adjuvant Treatment with Xiaoqinglong Formula for Bronchial Asthma in Acute Attack: A Systematic Review of Randomized Controlled Trials

BACKGROUND: XQLF (Xiaoqinglong formula) is the most commonly used prescription of traditional Chinese medicine in the treatment of asthma. XQLF combined with western medicine has been used to treat bronchial asthma in more and more cases, and good results have been achieved. Therefore, this meta-analysis aimed to evaluate the adjuvant treatment of traditional Chinese medicine classic herbal formula XQLF with bronchial asthma in acute attack. METHODS: The following electronic databases were systematically searched from inception to April 2019: PubMed, EMBASE database, Cochrane Library, China National Knowledge Infrastructure (CNKI), WanFang, VIP Database for Chinese Technical Periodicals, and China Biology Medicine (CBM). Two reviewers searched these databases and independently evaluated all the eligible articles for inclusion. Stata 14.0 was used for data synthesis and analysis. RESULTS: A total of 33 RCTs (randomized controlled trials) including 2176 patients were enrolled. All of the patients in these studies were in the acute attack stage of asthma. We conducted subgroup analysis according to the duration of treatment, which was 14 days, 10 days, and 7 days, respectively. The overall results show that adjuvant treatment with XQLF significantly improve CER (clinical efficacy rate) (RR = 1.17; 95% CI, 1.14 to 1.21; P < 0.0001) and promote pulmonary function including FEV1 (WMD = 0.35; 95% CI, 0.27 to 0.43; P < 0.0001), PEF (SMD = 1.02; 95% CI, 0.49 to 1.55; P < 0.0001), and FVC (WMD = 0.51; 95% CI, 0.35 to 0.66; P < 0.0001). The adjuvant treatment of XQLF can also reduce serum IgE concentration (SMD = −1.39; 95% CI, 1.92 to −0.85; P < 0.0001) and serum EOS concentration at 14 days (WMD = −39.85; 95% CI, −56.20 to −23.49; P < 0.0001). CONCLUSION: This study finally showed that XQLF has the auxiliary effect of improving the efficiency, promoting the lung function, and reducing the serum IgE in the treatment of acute attack asthma. This trial is registered with CRD42019133549.