The Effectiveness of Liu Zi Jue Exercise for Chronic Obstructive Pulmonary Disease (COPD): Systematic Review and Meta-analysis of Randomized Controlled Trials

Abstract

Background Liuzijue (LZJ), one of the traditional Chinese exercises, may influence the patients’ quality of life and pulmonary function, hence it might have beneficial effects in the treatment of chronic obstructive pulmonary disease (COPD). But evidence is still needed to evaluate LZJ’s effectiveness and potential subgroup differences. Therefore, a systematic review of relevant randomized controlled trials (RCTs) was performed to evaluate the effectiveness of LZJ on patient-important outcomes. Methods We systematically searched the Cochrane Library, Web of Science, PubMed, and Chinese databases since their inception until December 31,2021. Rigorous screening, risk of bias assessment, and data extraction have been performed in duplicate by two reviewers. A random effect model, with pre-specified subgroup analyses on type of comparisons were performed. Then we used a five-criteria list to assess the credibility of significant subgroup effects (P < 0.10). A GRADE evidence profile was established to assess the certainty of evidence. Results We included 22 eligible randomized controlled trials with 1304 patients. Compared with usual care, the standardized mean difference (SMD) on quality of life in the LZJ group is -0.67 (95%CI: [-0.96, -0.37], P < 0.0001). We found a statistical significance on FEV1% (MD = 5.75, 95%CI: [2.14,9.35], P = 0.002), FEV1 (MD = 0.26, 95%CI: [0.08,0.44], P = 0.004), and 6 minutes-walking distance(m)(MD = 38.04, 95%CI: [24.78,51.29], P < 0.00001). However, no differences were found for FVC (MD=-0.07, 95%CI: [-0.24,0.09], P = 0.38) and FEV1/FVC (MD = 6.51,95%CI: [-0.54,13.56], P = 0.07). The certainty of the evidence was low to very low because of the risk of bias, inconsistency, or indirectness. Conclusion Regularly exercising LZJ might be beneficial to the recovery of COPD based on evidence of low to very low certainty. Rigorously designed RCTs addressing patient-important outcomes with longer follow-up are still required. Trial registration: PROSPERO Registration number: CRD42021249739.