The risks and benefits of yoga for patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

Objectives: To determine the effectiveness and safety of yoga interventions on disease symptoms, quality of life and function in patients diagnosed with chronic obstructive pulmonary disease (COPD). Data sources: Medline/PubMed, Scopus, and CENTRAL (Cochrane Central Register of Controlled Trials) were searched through 6 June 2019. Review methods: Randomized controlled trials assessing the effects of yoga on quality of life, dyspnea, exercise capacity, and pulmonary function (FEV1) in patients with COPD were included. Safety was defined as secondary outcome. Mean differences (MD) and standardized mean differences (SMD) with 95% confidence intervals (CIs) were computed. Risk of bias was assessed using the Cochrane tool. Results: Eleven randomized controlled trials with a total of 586 patients were included. Meta-analysis revealed evidence for effects of yoga compared to no treatment on quality of life on the COPD Assessment Test (MD = 3.81; 95% CI = 0.97 to 6.65; P = 0.009, I 2 = 70%), exercise capacity assessed by the 6-minute walk test (MD = 25.53 m; 95% CI = 12.16 m to 38.90 m; P = 0.001, I 2 = 0%), and pulmonary function assessed by FEV1 predicted (MD = 3.95%; 95% CI = 2.74% to 5.17%; P < 0.001, I 2 = 0%). Only the effects on exercise capacity and pulmonary function were robust against methodological bias. Effects were only present in breathing-focused yoga interventions but not in interventions including yoga postures. Adverse events were reported infrequently. Conclusion: This meta-analysis found robust effects of yoga on exercise capacity and pulmonary function in patients with COPD. Yoga, specifically yoga breathing techniques, can be an effective adjunct intervention for patients with COPD. Yoga’s safety needs to be assessed in more depth in future studies.