TY - JOUR
T1 - Feasibility assessment of double-blind, crossover, randomized controlled trial protocol comparing two oxygen-supplemented pulmonary rehabilitation for patients with chronic obstructive pulmonary disease
T2 - A pilot study
AU - Ito, Akihiro
AU - Morito, Akane
AU - Ishizaka, Masahiro
AU - Ogawa, Yukihiro
AU - Kawai, Yuki
AU - Hanawa, Yuta
AU - Onodera, Naotaka
AU - Endo, Yoshiaki
AU - Fukushi, Isato
AU - Takeda, Kotaro
AU - Mochizuki, Taichi
AU - Inoue, Yasushi
AU - To, Yasuo
AU - Sakao, Seiichiro
AU - Chibana, Kazuyuki
AU - Yamasawa, Hideaki
AU - Fuke, Satoshi
AU - Kesler, Sarah
AU - Gozal, David
AU - Okada, Yasumasa
AU - Umeda, Akira
N1 - Publisher Copyright:
© 2026 Ito et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2026/5
Y1 - 2026/5
N2 - Background Pulmonary rehabilitation (PR) for patients with chronic obstructive pulmonary disease (COPD) improves exercise tolerance and COPD assessment test score (CAT). Oxygen supplementation during PR facilitates exercise physiological benefits. This study aimed to assess the feasibility of a trial comparing two oxygen supplementation methods, with the hypothesis that both would be effective and produce distinct outcomes. Methods This double-blind, crossover, randomized controlled trial compared two PR programs—Program A (including PR under FiO2 0.3) and Program B (including PR under FiO2 0.5)—using high-flow nasal cannula oxygen therapy in patients with COPD and exertional dyspnea (n = 6). Data on the 6-minute walk distance (6MWD), CAT, muscle strength, body composition analysis, respiratory function, and joint range of motion were collected. Participants underwent one month of regular PR followed by two months of oxygen-supplemented PR, with data collected again after this period. Statistical significance was set at 0.05 with a power of 0.8, and the required sample size was calculated accordingly. Results The required sample size could not be calculated based on the 6MWD. The improvement in CAT by Program A was greater than that by Program B. The improvements in muscle parameters by Program B were greater than those by Program A. The standardized effect size and the corresponding required sample sizes for the CAT, quadriceps muscle power, lower leg circumference, trunk muscle mass, and leg muscle mass were 0.32/81, 0.66/8, 0.17/114, 0.27/88, and 0.24/56, respectively. Conclusions Given the small number of participants, the 6MWD and CAT were not appropriate primary endpoints for comparing the effectiveness of the two oxygen supplementations during PR in patients with COPD. However, the quadriceps muscle power was identified as the most suitable primary endpoint among all the investigated parameters.
AB - Background Pulmonary rehabilitation (PR) for patients with chronic obstructive pulmonary disease (COPD) improves exercise tolerance and COPD assessment test score (CAT). Oxygen supplementation during PR facilitates exercise physiological benefits. This study aimed to assess the feasibility of a trial comparing two oxygen supplementation methods, with the hypothesis that both would be effective and produce distinct outcomes. Methods This double-blind, crossover, randomized controlled trial compared two PR programs—Program A (including PR under FiO2 0.3) and Program B (including PR under FiO2 0.5)—using high-flow nasal cannula oxygen therapy in patients with COPD and exertional dyspnea (n = 6). Data on the 6-minute walk distance (6MWD), CAT, muscle strength, body composition analysis, respiratory function, and joint range of motion were collected. Participants underwent one month of regular PR followed by two months of oxygen-supplemented PR, with data collected again after this period. Statistical significance was set at 0.05 with a power of 0.8, and the required sample size was calculated accordingly. Results The required sample size could not be calculated based on the 6MWD. The improvement in CAT by Program A was greater than that by Program B. The improvements in muscle parameters by Program B were greater than those by Program A. The standardized effect size and the corresponding required sample sizes for the CAT, quadriceps muscle power, lower leg circumference, trunk muscle mass, and leg muscle mass were 0.32/81, 0.66/8, 0.17/114, 0.27/88, and 0.24/56, respectively. Conclusions Given the small number of participants, the 6MWD and CAT were not appropriate primary endpoints for comparing the effectiveness of the two oxygen supplementations during PR in patients with COPD. However, the quadriceps muscle power was identified as the most suitable primary endpoint among all the investigated parameters.
UR - https://www.scopus.com/pages/publications/105037919325
UR - https://www.scopus.com/pages/publications/105037919325#tab=citedBy
U2 - 10.1371/journal.pone.0348404
DO - 10.1371/journal.pone.0348404
M3 - Article
C2 - 42096422
AN - SCOPUS:105037919325
SN - 1932-6203
VL - 21
JO - PloS one
JF - PloS one
IS - 5 May
M1 - e0348404
ER -