Depression Symptoms and Physical Activity in Veterans With COPD: Insights From a Web-Based, Pedometer-Mediated Physical Activity Intervention

Lay Summary United States (U.S.) Veterans have high rates of chronic obstructive pulmonary disease (COPD), a progressive lung disease that causes shortness of breath. Promoting physical activity (PA) is an important component to the management of COPD resulting in improved outcomes. Technology-based interventions (i.e., pedometers, websites) are effective at increasing PA in persons with COPD. However, depression symptoms, such as low mood and motivation, may influence their effectiveness. This secondary data analysis examined whether depression symptoms were related to improvement in daily step count. Two cohorts of U.S. Veterans were randomized to either a web-based, pedometer-mediated PA intervention (i.e., pedometer, goal setting and feedback, education and online community) or a control group (i.e., pedometer only or usual care). Daily step count was assessed at baseline and at 3 months. Across both groups, greater overall depression symptoms and greater bodily symptoms of depression (i.e., fatigue) were associated with less improvement in daily step count. Veterans with greater cognitive-affective symptoms of depression (i.e., low mood, loss of interest, or pleasure) who were assigned to the intervention group showed no improvement in daily step count compared with controls. Results highlight the importance of detecting and treating depression as part of PA interventions. Background Depression is known to limit physical activity (PA) among individuals with chronic obstructive pulmonary disease (COPD). However, whether and how depression influences the effectiveness of PA interventions is unknown. Purpose The study examined the association between baseline depression symptoms and change in daily step count and whether group assignment to a web-based, pedometer-mediated PA intervention moderated the association between baseline depression symptoms and change in daily step count. Methods Secondary analysis included two cohorts of U.S. Veterans with COPD (n = 212; 97% male; mean age 69 +/- 8 years) assessed at baseline and 3 months. Cohorts 1 and 2 were randomly assigned to the same PA intervention (n = 111) or a control group (n = 101). Multivariate regressions tested the main effects of baseline depression symptoms (BDI-II total and cognitive-affective and somatic subscales) on change in daily steps, as well as the interaction between baseline BDI-II and subscales and group assignment on change in daily steps. Results Greater BDI-II total score (B = -31.8, SE = 14.48, p = .030) and somatic subscale scores (B = -99.82, SE = 35.76, p = .006) were associated with less improvement in daily step count. There was a significant interaction between baseline cognitive-affective subscale and the intervention predicting change in daily step count (B = -88.56, SE = 42.31, p = .038). When cognitive-affective subscale scores were >= 1 SD above the mean, the intervention was no longer associated with an increase in daily step count (p = .585). Conclusions Depression should be routinely assessed and targeted as part of PA promotion efforts.

Automated summary

US Veterans with high rates of chronic obstructive pulmonary disease (COPD) often suffer from depression symptoms which can hinder the effectiveness of technology-based interventions promoting physical activity. This study analyzed data from two cohorts of US veterans and found that greater depression symptoms were associated with less improvement in daily step count, and individuals with cognitive-affective symptoms of depression showed no improvement in daily step count when assigned to the intervention group.