Predictive Models of Cognitive Fatigue in Multiple Sclerosis

Abstract

Objective: Cognitive fatigue (CF) can be defined as decreased performance with sustained cognitive effort. The present study examined the interrelatedness of disease severity, fatigue, depression, and sleep quality in order to evaluate their predictive roles of CF in MS. Four theoretical models examining these variables were assessed. Methods: Fifty-eight individuals with a diagnosis of MS were recruited. CF was measured by examining last third versus first third performance on the Paced Auditory Serial Addition Test (PASAT). The PASAT and self-report measures of fatigue, depression, and sleep quality were administered. Path analysis was used to evaluate each of the models. Results: CF was correlated only with depression (r =. 362, p =. 006) and sleep quality (r =. 433, p =. 001). Sleep quality was the greatest significant independent predictor of CF (β =. 433, t(1,55) = 3.53, p