Effect of adding neuromuscular electrical stimulation for patients with moderate to severe chronic obstructive pulmonary disease: Systematic review and meta-analysis

Background: Healthcare providers have faced challenges for patients with moderate and severe chronic obstructive pulmonary disease (COPD) in conducting their pulmonary rehabilitation due to dyspnea and exercise intolerance. Neuromuscular electrical stimulation (NMES) has been used to improve the muscle group's power and endurance without adding pulmonary workload, which might be used as a potential adjuvant rehabilitation method and thus to improve patients' pulmonary functions. Methods: This was a systematic review and meta-analysis of randomized controlled trials. Data were retrieved from PubMed, CINAHL, Academic Search Complete, Cochrane Library, and Airiti Library databases from the inception of the database to December 2022. The Cochrane Collaboration tool was used to assess the risk of bias. Two reviewers independently assessed, extracted, and appraised the included studies. Then, the grading of recommendations, assessment, development, and evaluation (GRADE) methodology was used for assessing the certainty of evidence. The pooled estimates were calculated using a random-effects model. Results: In total, 19 studies involving 589 moderate to severe COPD patients were analyzed. Compared with controls, adding NMES to pulmonary rehabilitation could significantly increase exercise capacity, physical activity function, and health-related quality of life (HRQoL) (all p < 0.05). The GRADE results showed low to very low certainty of evidence levels. Conclusion: NMES could improve exercise capacity and reduce the perceived sensation of dyspnea during exercise and is recommended as an effective adjuvant training modality in the rehabilitation for moderate to severe COPD patients.