Differences in Sedentary Time, Light Physical Activity, and Steps Associated with Better COPD Quality of Life.

Abstract

Introduction: There is a knowledge gap about how much physical activity is recommended to patients with chronic obstructive pulmonary disease (COPD). We asked, what is the average difference in sedentary time and physical activity associated with clinically meaningful differences in symptoms in a large, well-characterized cohort of patients with advanced COPD?

Study design and methods: We conducted a cross-sectional analysis of daily activity data in 292 patients with stable COPD. Activity measure coefficients from multivariable linear models were used to predict the average difference in activity between patients with twice the minimal clinically important difference in reported symptoms.

Results: Symptoms were assessed with the Chronic Respiratory Disease Questionnaire subdomains - dyspnea, fatigue, mastery, and emotions. Daily steps, minutes in light physical activity, and sedentary time were measured by triaxial accelerometers. Average sedentary time, light physical activity, and steps were 767.6 minutes, 177.7 minutes, and 2960 steps, respectively. Individuals with 1-point better dyspnea scores averaged 24.5 (8.4-40.5) minutes less sedentary time per day. Individuals with 1-point better dyspnea and fatigue scores averaged 21.5 (10.9-32.3) minutes or 12.5 (2.0-23.2) minutes more light physical activity per day, respectively. Individuals with 1-point better dyspnea, fatigue, mastery, and emotions scores averaged 762 (546-984), 579 (351-814), 418 (207-636), and 392 (157-634) more steps per day, respectively.

Conclusions: We provide guidance to clinicians counseling patients with severe COPD in activity-related goal setting on sedentary time, light physical activity, and steps associated with better symptoms.