Physical activity, disability, and mood in the early stage of multiple sclerosis

Background: Early multiple sclerosis (MS) may constitute a period of particular vulnerability to psychological distress such as anxiety and depression. Physical activity is a potentially modifiable, behavioral correlate of anxiety and depression in the early stages of MS. Objective: The present study provides an initial examination of the associations between physical activity and anxiety and depression in early MS. We hypothesized that physical activity might be a correlate of anxiety and depression in early MS and that this association might be indirect and accounted for by disability. Methods: The sample included 96 individuals with a mean duration of MS of 3.0 years (SD = 1.5, range = 0.5-5 years). The participants wore an accelerometer for 7 days as an objective measure of physical activity and then completed the Patient Determined Disease Steps (PDDS) scale and Hospital Anxiety and Depression Scale (HADS). Results: Descriptive analysis indicated that 41% and 43% of the sample had elevated levels of anxiety and depression, respectively, based on HADS scores (i.e., score >= 8). Correlation analysis indicated that physical activity was significantly associated with depression (r = -0.25; rho = -.23), but not anxiety (r = -0.05; rho = -.02). Path analysis indicated that the association between physical activity and depression was entirely indirect by way of disability (path coefficient = -0.23). Conclusions: Such results suggest that physical activity could be an important health promoting behavior for reducing depression in the early stages of MS and this should be the focus of subsequent randomized controlled clinical trials. (C) 2010 Elsevier Inc. All rights reserved.