Understanding the impact of physical activity in COPD outcomes: moving forward.

Abstract

Arguably, three outcome categories are of greatest importance to chronic obstructive pulmonary disease (COPD) patients, their families and their caregivers: health-related quality of life (including symptom burden); hospitalisations and other forms of healthcare utilisation; and, of course, mortality. Lower levels of baseline physical activity are not only prevalent in patients with COPD [1, 2], they are associated a negative impact in each of these three outcome categories [3–5]. Of considerable importance to healthcare professionals, increases in physical activity appear to predict enhanced health-related quality of life and reduced hospitalisations. For example, in an analysis of 391 patients with COPD who had physical activity and health-related quality of life assessments at baseline and 5 years later [6], those who increased or maintained their high levels of physical activity had clinically meaningful improvements in quality of life. In contrast, those who stayed at a low level or decreased their physical activity had a worsening in this outcome. From one perspective, this comes close to a tautology, as physical function impairment and distressing symptoms associated with physical activity are prominent components of health-related quality of life questionnaires. With respect to healthcare utilisation, a longitudinal analysis of COPD patients over 5 years demonstrated that the change in physical activity over the first 2 years significantly predicted hospitalisations 3 years later: those without regular physical activity, those who maintained a low level of physical activity or those who decreased their physical activity were at significantly greater risk of being hospitalised than …