Do Device-Measured Physical Activity and Sedentary Behavior Differ By Depression Symptom Status in Persons with MS?

Background: Depression is highly prevalent and impactful in persons with MS. There are data indicating that the volume of physical activity behavior differs by depression symptom status in MS, yet very little is known about the volume of sedentary behavior and depression. We further know little about the patterns of physical activity and sedentary behavior and depression in MS.

Objectives: This study examined differences in the volume (i.e., minutes/day) and pattern (i.e., bouts/day or bout length) of device-measured sedentary behavior and physical activity as a function of depression symptom status in persons with MS.

Methods: The sample of adults with MS (N=441) completed the Hospital Anxiety and Depression Scale (HADS) and wore a waist mounted ActiGraph GT3X+ accelerometer during waking hours for 7 days. Participants were divided into subgroups of elevated (n=127) or non-elevated (n=314) depression symptom scores based on a cut-point for the HADS (i.e., 8+ as indicative of elevated depressive symptoms). We examined differences in volume and pattern of sedentary behavior and light (LPA) and moderate-to-vigorous physical activity (MVPA) between subgroups using independent samples t-tests, and expressed the magnitude of differences using Cohen’s d.

Results: There were no significant differences in total sedentary time (p=.690, d=-.042), total sedentary bouts per day (p=.894, d=-.014), sedentary bout length (p=.618, d=-.009), total time of sedentary bouts per day (p=.894, d=.014), or sedentary breaks (p=.931, d=.009) between those with elevated and non-elevated depression symptom scores. There further were no significant differences for LPA (p=.099, d=-.174), MVPA (p=.172, d=-.144), average bouts per day of PA (p=.445, d=-.080), and MVPA bout length (p=.334, d=-.102). There was a significant difference in steps/day (p=.003, d=.310) between those with elevated and non-elevated depression symptoms scores.

Conclusions: This study demonstrated no differences in sedentary behavior and physical activity as a function of depression symptom status in persons with MS, yet there was a difference in steps/day. This suggests that steps/day could be an important target of health promotion interventions among persons with MS who have elevated depression symptoms.