Correlates of physical activity in chronic obstructive pulmonary disease

Background: Physical activity is a key dimension of functional status in pe ople with chronic obstructive pulmonary disease (COPD), and the central tar get of interventions in this group. Objectives: To determine the relationships among functional performance mea sured as physical activity, functional capacity, symptom experiences, and h ealth-related quality of life in people with COPD. Method: Cross-sectional, descriptive study. Convenience Sample of 63 outpat ients with COPD studied prior to entry into a pulmonary rehabilitation prog ram. Results: Daily physical activity, as measured by an accelerometer, was stro ngly associated with maximal distance walked during a 6-minute walk test (r = .60, p < .00), level of airway obstruction (r = .37, p < .01), walking s elf-efficacy (r = .27, p < .05), and physical health status (r =.40, p < .0 1). Physical activity was not correlated with self-report of functional sta tus. The only predictor of physical activity was the 6-minute walk test. 1 Conclusions: Accelerometer measurement of functional performance was most s ignificantly related to walking abilities. This methodology represents a no vel approach to measuring an important dimension of functional status not p reviously well quantified.