Baseline characteristics associated to improvement of patients with COPD in physical activity in daily life level after pulmonary rehabilitation.

Abstract

BACKGROUND\nKnowing the patients with chronic obstructive pulmonary disease (COPD) that increase the physical activity of daily living (PADL) after pulmonary rehabilitation (PR) is a challenge.\n\n\nAIMS\nto compare baseline characteristics between patients who achieved and failed to achieve the minimal important difference (MID) of PADL post-PR; to verify which baseline variables better predict the change and identify a cut-off point to discriminate MID achievers.\n\n\nMETHODS\nFifty-three patients with COPD (FEV1: 38.3; 95%CI 34.4-42.2%pred) were evaluated for spirometry, dyspnea, quality of life, functional capacity, mortality risk and PADL level. After 24 sessions of PR had their PADL level revaluated.\n\n\nRESULTS\nThe MID achievers presented lower FEV1, functional capacity, time walking, number of steps, active time, energy expenditure (EE) walking, time on PADL≥3 metabolic equivalent of task (METs) and higher time on PADL<1.5MET. Inactive patients and with severe physical inactivity presented a hazard ratio of 4.27 and 6.90 (95%CI: 1.31-13.9, p\u202f=\u202f0.02; 95%CI: 1.99-23.9, p\u202f=\u202f0.002; respectively) for achieving the MID. The variables of predictive model for the change in the PADL were EE walking and time on PADL<1.5MET (R2: 0.37; p\u202f=\u202f0.002). The cut-off point of 6525 steps [sensitivity\u202f=\u202f95%; specificity\u202f=\u202f61%; AUC\u202f=\u202f0.82 (95%CI: 0.71-0.93), p\u202f<\u202f0.001] was able to discriminate patients who achieved and failed to achieve the MID.\n\n\nCONCLUSION\nPatients with worse lung function, functional capacity and lower PADL level before PR are those that improve the PADL level. EE walking and time on PADL<1.5MET better predict this change. The cut-off point of 6525 steps can help to identify patients with higher chances of improving the PADL level.