Self-reported task-oriented physical activity: A comparison with objective daily step count in COPD.

Abstract

Low physical activity (PA) is associated with adverse health outcomes independent of airflow limitation in COPD. Self-reported assessments are often limited to global estimates of PA and may not be directly translatable to patients' goals and motivations. We developed a task-oriented PA checklist and examined its performance relative to pedometer-assessed daily step count in two COPD cohorts. Task-oriented daily physical activity (DPA) was assessed in two COPD cohorts using either interviewer-administered recall questionnaire (DPA-R, Cohort 1, n = 109) or a self-administered diary-format daily checklist (DPA-C, Cohort 2, n = 175). Daily step count was measured in both cohorts using the Omron HJ-720 ITC pedometer. Univariate associations between individual DPA items and [a] cross-sectional and [b] longitudinal change (Cohort 1) in daily step count were assessed using a Pearson's correlation. Composite scores comprised of individual DPA items with univariate association p-values <0.1 were tested for association with daily step count using multivariate models. Tasks associated with average daily step count in both cohorts included putting on shoes, showering, washing hair, walking for exercise, the frequency of walks >10 min, and walking on an incline (Pearson's rho range = 0.14-0.43). A composite score of these 6 DPA items demonstrated significant associations with baseline average daily step count in both cohorts (ρ = 0.5 & 0.47, Cohorts 1 & 2, respectively) and longitudinal change in daily step count (ρ = 0.46, Cohort 1). Self-reported task-oriented assessments complement direct monitoring and have potential clinical utility in exercise counseling to increase PA among COPD patients. ClinicalTrials.gov NCT01772082.