Combination of Pulmonary Rehabilitation and Neuromuscular Electrical Stimulation in COPD Patients: A Randomized Clinical Trial of Efficacy

Abstract

Aims:Effectiveness of combination of pulmonary rehabilitation (PR) and neuromuscular electrical stimulation (NMPR) in severe chronic obstructive pulmonary disease (COPD) is well established. We verified the effects of NMPR compared with pulmonary rehabilitation and sham stimulation (SSPR) in patients with moderately impaired COPD. Methods:Quadriceps strength (sit-to-stand test: STST) and exercise capacity (6 minute walking test: 6MWT) were considered primary outcomes. Lung function, dyspnoea (modified Medical Research Council: mMRC) and quality of life (St. George’s Respiratory Questionnaire: SGRQ) secondary outcomes. Results:83 stable patients in stage II, moderate COPD (23 female; mean age, 61.7 ± 9.1 years; FEV1 59.8 ± 7.3% of predicted) were enrolled. Quadriceps strength was enhanced by SSPR (STST + 7±1.7 repetitions; p≤0.001); NMPR further increased strength (+10±1.6 repetitions; p≤0.001) with a significant difference (p≤0.05) between the treatments. SSPR significantly increased exercise capacity (6MWD + 85.3±11.5 m; p=0.01); NMPR further increased the distance walked (6MWD +146.4±32.7 m; p=0.01) with a significant difference (p≤0.05) between the treatments. None of the two treatments influenced lung function. Quality of life score (SGRQ – 8.3±2.1; p=0.01) and dyspnoea score (mMRC-0.7±0.18; p=0.01) decreased after SSPR suggesting a positive effect. NMPR did not further improve the score. Conclusions:This study confirms that PR is able to ameliorate quadriceps strength, exercise capacity, quality of life and dyspnoea in moderately impaired COPD patients. NMPR may further improve quadriceps strength and exercise capacity with respect to PR alone.