Assessing the Effect of reducing Pulmonary Rehabilitation Group Training weeks from 13 to 7 on the 6-min Walking Test Outcomes in COPD Patients: A retrospective Cohort Study

This study showed that a 7- week PR group training programme, following 9 one- on one coaching and introduction sessions, is non- inferior to a 13- week group training programme relating to results in the 6 Minutes Walk Test (6MWT). Non- Inferiority Analysis Using ANCOVA analyses of the 6MWT times showed that test results at the end of pulmonary rehabilitation (PR) were strongly and significantly associated with results in the baseline test (F=80.2, p: >0.001) and no significant difference between endpoints in both cohorts (F=0.019, p= 0.89). Mean (95%CI) values of the 6MWT results at the end of the programme were 423.9 (394.3 – 453.5) in cohort 1 and 421.2 (396.3 – 446.1) meters in cohort 2. Pairwise comparison of cohort 1 to 2 showed a non- significant mean difference (95%CI) of -2.7 (-36.5 – 41.8) meters. Individual Efficacy of the Programmes Within-group analyses by paired t- test of cohort 1 (13 weeks) (N=15) showed a 6MWT mean (standard error, SE) of 416.2 (29.1) meters before PR and 445.1 (28.4) after, resulting in a non- significant mean clinical difference (95% CI) of 28.9 (-1.1 – 58.9) (p=0.058) meters. Cohort 2’s (7 weeks) paired t- test (N=21) showed a 6MWT mean (SE) of 371.6 (21.5) meters before PR and 406.0 (20.8) after, resulting in a significant mean clinical difference (95% CI) of 34.4 (6.8 – 61.9) (p=0.017) meters. As cohort 2 reached the MCID of 30 meters, 7 weeks of PR are enough to elicit meaningful change in patients when looking at exercise capacity. And while the small sample size and design of the evaluated programme limited comparability, the author cautiously suggests that the 13- week programme would probably have reached the MCID as well, if a larger sample was studied.