A-12 Physical Activity Attenuates the Effect of Pain on Depression Symptoms in Multiple Sclerosis

Abstract

Abstract Objective: This study examined physical activity as a potential moderator of the relationship between pain and depression symptoms in persons with multiple sclerosis (PwMS). We hypothesized that pain would predict depression symptoms only in PwMS with low physical activity. Method: Fifty-four PwMS (38 female) completed a comprehensive neuropsychological test battery and questionnaires. Pain was operationalized as a composite of measures from the Brief Pain Inventory (BPI). The metabolic equivalents (METs) of energy expended during vigorous activity (VA), moderate activity (MA), and walking, as well as global activity which combined the three, were derived from the International Physical Activity Questionnaire-Short Form (IPAQ-SF) based on parameters previously used by Dlugonski et al. (2011). Lower METs suggest less physical activity. The Beck Depression Inventory-Fast Screen (BDI-FS) was used to measure depression symptoms. Linear regressions on depression examining pain, each physical activity index, and their interactions were explored. Results: Regression analyses showed that the interaction between pain and global MET significantly predicted depression (p = 0.01). Simple effects tests revealed that pain predicted depression symptoms only in PwMS with low MET scores (p < 0.001). The separate interactions between pain and VA, MA, and walking predicting depression symptoms were not significant. Conclusion: We found that global physical activity moderated the relationship between pain and depression in MS. Specifically, pain predicted depression symptoms in PwMS who engaged in less physical activity. These results highlight the importance of screening PwMS for pain and suggest that interventions aimed at increasing overall physical activity may be useful in improving depression outcomes in PwMS with pain.