Expanding the Connection Between Cognition and Illness Intrusiveness in Multiple Sclerosis.

Background: Multiple sclerosis (MS) disease factors, such as cognitive impairment, can cause disruptions in meaningful activities, also known as illness intrusiveness. Although the association between specific objective measures of cognition and illness intrusiveness has been documented in MS, the contributions of individuals' perceptions of their cognition or whether any psychological factors can buffer the relationship have yet to be explored. This study aimed to (1) simultaneously examine objective processing speed and subjective cognition as disease factors contributing to illness intrusiveness and (2) explore whether resilience moderates the relationship between cognition and illness intrusiveness.

Methods: Participants (N = 112) were individuals with MS who completed the Illness Intrusiveness Ratings Scale (IIRS), Symbol Digit Modalities Test (SDMT), Perceived Deficits Questionnaire (PDQ), and MS Resiliency Scale (MSRS) as part of a larger cross-sectional study. A hierarchical linear regression was done, followed by individual moderation analyses.

Results: Both the PDQ (b = .43, P = .001) and SDMT (b = -4.17, P = .003) were independent predictors of the IIRS. There was no evidence of moderation in either model, although the MSRS independently contributed to the IIRS.

Conclusions: Among individuals with MS, objective processing speed and subjective cognition were independently associated with illness intrusiveness, highlighting the importance of considering both cognitive performance and perceptions as contributing factors to life disruptions.