Effectiveness of pulmonary rehabilitation in COPD with mild symptoms: a systematic review with meta-analyses

Purpose: Most guidelines recommend pulmonary rehabilitation (PR) for patients with chronic obstructive pulmonary disease (COPD) and modified Medical Research Council dyspnea scale (mMRC) levels. > 2, but the effectiveness of PR in patients with less advanced disease is not well established. Our aim was to investigate the effects of PR in patients with COPD and mMRC. <= 1. Methods: The methodology was developed as a part of evidence-based guideline development and is in accordance with the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group. We identified randomized controlled trials (RCTs) through a systematic, multidatabase literature search and selected RCTs comparing the effects of PR with usual care in patients with COPD and mMRC. < 1. Predefined critical outcomes were health-related quality of life (HRQoL), adverse effects and mortality, while walking distance, maximal exercise capacity, muscle strength, and dropouts were important outcomes. Two authors independently extracted data, assessed trial eligibility and risk of bias, and graded the evidence. Meta-analyses were performed when deemed feasible. Results: Four RCTs (489 participants) were included. On the basis of moderate-quality evidence, we found a clinically and statistically significant improvement in short-term HRQoL of 4.2 units (95% confidence interval [CI]: [-4.51 to -3.89]) on StGeorge's Respiratory Questionnaire, but not at the longest follow-up. We also found a statistically significant improvement of 25.71 m (95% CI: [15.76-35.65]) in the 6-minute walk test with PR; however, this improvement was not considered clinically relevant. No difference was found for mortality, and insufficient data prohibited meta-analysis for muscle strength and maximal exercise capacity. No adverse effects were reported. Conclusion: We found a moderate quality of evidence suggesting a small, significant improvement in short-term HRQoL and a clinically nonsignificant improvement in walking distance following PR in patients with COPD and mild symptoms. This resulted in a weak recommendation of routine PR in these patients using the GRADE approach.