Abstract
BACKGROUND: Exercise intolerance is among the most common symptoms experienced by patients with chronic obstructive pulmonary disease (COPD), which is associated with lung dynamic hyperinflation (DH). There was evidence that positive expiratory pressure (PEP), which could be offered by less costly devices, could reduce DH. The purpose of this study was to evaluate the efficacy and safety of long-term domiciliary use of PEP device in subjects with COPD. METHODS: A randomized controlled trial was conducted and 25 Pre-COPD or mild-to-very severe subjects with COPD were randomized to intervention group (PEP device, PEP = 5 cmH(2)O, n = 13) and control group (Sham-PEP device, PEP = 0 cmH(2)O, n = 12). PEP device was a spring-loaded resistor face mask. Subjects were treated 4 h per day for a total of 2 months. Six-minute walk test (6MWT), pulmonary function, the Modified British Medical Research Council score, and partial pressure of end-tidal carbon dioxide were evaluated at baseline and after two months. RESULTS: The 6MWD (- 71.67 ± 8.70 m, P < 0.001), end-dyspnea (P = 0.002), and end-fatigue (P = 0.022) improved significantly in the intervention group when compared with the control group. All subjects in the intervention group reported that 4 h of daily use of the PEP device was well tolerated and accepted and there were no adverse events. CONCLUSION: Regular daily use of PEP device is safe and may improve exercise capacity in subjects with COPD or pre-COPD. PEP device could be used as an add-on to pulmonary rehabilitation programs due to its efficacy, safety, and low cost. TRIAL REGISTRATION: The study was prospectively registered on ClinicalTrials.gov (NCT04742114).