Influence of changes in physical activity (PA) and exercise capacity on mortality and quality of life (QL) in COPD

Objective: To evaluate the predictive capacity of changes in PA and in exercise capacity in relation to mortality and QL for 5 years in COPD. Methods: 543 COPD patients were included. The follow-up was done during 5 years. PA was self-reported by patients (distance walked in Km/day) practiced who did it at least 3 days/ week and the exercise capacity was determined by a six-minute walking test (6MWT). The changes in both variables were evaluated. 7 categories were established according to the change in PA, and 3 groups according to the change in 6MWT (worsening, no change, improvement), considering a distance of 25m as the minimum clinically significant change. Mortality and QL within the following 3 years were the outcome assessed according to St George’s Respiratory Questionnaire (SGRQ). Univariate and multivariate analyses were performed. Results: The average age was 68 years, dyspnea 2mMRC, Charlson index 2.4 and FEV1 55%. The 6MWT was 408.9m and SGRQ 39.2. Both the worsening in PA and 6MWT were associated with more mortality and less QL (p Conclusions: –The change in PA and in 6MWT was associated with mortality and QL in COPD and the change in PA was better, in relation to mortality and QL. –When the PA and the 6MWT were associated, the predictive capacity in relation to both response variables improved.