Use of Cognitive Screening and the Influence of Psychosocial Variables in Identification of Cognitive Impairment in MS

Abstract

BACKGROUND: The purpose of this project is to examine the potential of abbreviated cognitive screening to identify patients with clinically significant cognitive dysfunction. A secondary goal is to examine relationships between cognitive functioning and psychosocial factors of disease. SUBJECTS: The study includes 94 subjects with a Demyelinating disease [M age = 45.04 (11.08); M education = 15.40 (2.13)] who were referred to the University of Texas Southwestern Medical Multiple Sclerosis Clinical Center and Multiple Sclerosis Program and signed informed consent for a larger study on cognition in multiple sclerosis and demyelinating disease. METHOD: Subjects completed a screening battery (JoL, 9HPT, PASAT, SDMT-Oral, and T25FW) at visit one and a larger cognitive assessment within 4 weeks of visit one, which was used to divide subjects into impaired and non-impaired groups. Linear regression was used to assess which tests on the screening battery predicted impairment on the longer battery. Associations between psychosocial factors of depression, fatigue, and sleepiness were examined in relation to cognitive performance. The relationship between depression and objective versus subjective cognitive performance was also examined. RESULTS: The PASAT (p = .001) was the only measure in the screening battery that predicted group membership, with correct classification of 76% of subjects using a cut score of T ² 38. Depression (QIDS-SR) was significantly correlated with self-reported cognitive dysfunction (MSNQ) (r = .57; p = <.001) but only modestly associated with the four measures on the screening battery (r = -.17 to .25). Those who endorsed depressive symptoms performed lower on JoL(p = .003), PASAT (p = .015) and SDMT (p = .023). Level of fatigue was associated with cognitive performance, as significant mean differences were found on all screening battery measures in high versus low fatigue groups. There was no impact of sleepiness on cognition. DISCUSSION: Complex attention was the most sensitive measure for predicting cognitive impairment on a more comprehensive battery and may be a good screening tool in identifying who might benefit from more detailed testing. Higher levels of depression and fatigue significantly impacted test performance and highlight important areas for screening and treatment, while daytime sleepiness had no effect.