Background: Depression is highly prevalent and influences physical function and mobility disability in persons with MS. There are data indicating the depression is further associated with the volume and pattern of physical activity behavior in MS, yet very little is known about depression and sedentary behavior. If there is evidence for higher sedentary behavior in persons with MS who have elevated depressive symptoms, this might serve as a target of behavior change interventions that reduce sedentary behavior and replace it with physical activity.
Objectives: The present study examined differences in volume and pattern of device-measured sedentary behavior (i.e., sedentary minutes per day and bouts of sedentary behavior) as a function of depressive symptoms in persons with MS.
Methods: The sample included (N=188) adults with MS who completed the Hospital Anxiety and Depression Scale (HADS) and wore a waist-mounted ActiGraph GT3X+ accelerometer during the waking hours for 7 days. Patients were divided into subgroups of normal (n=128) or elevated (n=60) depressive 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 (i.e. total sedentary minutes per day, total sedentary bouts per day, bout length, total time of sedentary bouts, and sedentary breaks) between subgroups using independent samples t-tests, and expressed the magnitude of differences using Cohens d.
Results: There were no significant differences in total sedentary time (p=.194, d=.047), total sedentary bouts per day (p=.348, d=.125), sedentary bout length (p=.296, d=-.077), total time of sedentary bouts per day (p=.125, d=.195) or sedentary breaks (p=.490, d=.126) between those with elevated and normal depression symptoms scores.
Conclusions: This study demonstrated no differences in sedentary behavior as a function of depression symptom scores in persons with MS. This suggests that the volume and pattern of sedentary behavior is not determined by depression in MS, yet it is still substantially elevated in MS as a whole and requires focal intervention.