BackgroundWearing masks imposes an additional respiratory burden on COPD patients. This study aimed to investigate the impact of various mask types on physiological parameters and subjective feelings in COPD patients.MethodsThis randomized, open-label, parallel-controlled trial randomly assigned 129 COPD patients from 2 Chinese hospitals to the N95 mask group, the surgical mask group and the no mask group, who were required to complete a 6-minute rest (6MR) and a 6-minute walking test (6MWT) while wearing their designated masks, and were assessed for blood pressure, oxygen saturation, pulse rate, Borg score, RPE score, 6-minute walk distance (6MWD), and subjective feeling score. Data were analyzed using intention-to-treat analysis and per-protocol analysis.ResultsNo significant differences were observed in blood pressures, oxygen saturation, pulse rate, or the 6MWD among the three groups following a 6MR or 6MWT. Wearing N95 masks and surgical masks during the 6MWT significantly elevated perceived dyspnea (p<0.001) and exertion scores (p<0.001) in COPD patients. The differences in the 2 scores between the highest and lowest groups were 2 and 4 points, respectively.ConclusionWearing surgical masks or N95 masks for 6MR or 6MWT did not adversely affect physiological parameters in COPD patients. However, it significantly increased perceived dyspnea and exertion.