Pain-related illness intrusiveness is associated with lower activity engagement among persons with multiple sclerosis.

Background: Pain can interfere with the daily functioning of persons with multiple sclerosis (PwMS). Furthermore, beliefs about pain and activity engagement are reliably associated with persons' experience of chronic pain. This study aimed to explore the extent to which different aspects of PwMS' activity engagement is related to pain-related illness intrusiveness, and whether certain coping and support systems mediate that relationship.

Methods: Participants (N = 161) were PwMS with at least mild pain who were recruited electronically through the North American Research Committee on MS (NARCOMS). Pain-related illness intrusiveness was measured using a modified version of the Illness Intrusiveness Ratings Scale (IIRS). Activity engagement was assessed with Section III of the West Haven-Yale Multidimensional Pain Inventory (WHYMPI). Correlations analyses were followed by multiple hierarchical regressions, with disability and depression symptom severity as covariates. Exploratory mediation analyses were then conducted with the subscales of the MS Resiliency Scale (MSRS).

Results: Pain-related illness intrusiveness was significant correlated with activities away from home (r = -0.37, p < .001), social activities (r = -0.26, p = .001), and household chores (r = -0.16, p < 0.05). After controlling for covariates, pain-related illness intrusiveness exclusively remained a significant predictor of activities away from home. Coping strategies from MSRS mediated the effect of pain-related illness intrusiveness on activities away from home (b = -0.01, p < .05), which represents a relatively small effect (R = 0.07).

Conclusions: These findings highlight the influence that PwMS' pain experience can have on engagement in activities away from home and the indirect effects of positive coping strategies on that relationship.