TITLE:
Correlation between Cognitive Functions, Fatigue, Depression and Disability Status in a Cohort of Multiple Sclerosis Patients
AUTHORS:
Seyed Massood Nabavi, S. Tahbaz, A. Salahesh, Z. Behjati, F. Nourbala, S. Sadeghi, Z. Saeedi, D. Morsali, Shima Haghani
KEYWORDS:
Fatigue, Depression, Cognitive Dysfunction, Disability, Multiple Sclerosis
JOURNAL NAME:
World Journal of Neuroscience,
Vol.6 No.3,
July
20,
2016
ABSTRACT: Objective: To investigate
the relationship between depression, fatigue, disability and cognitive skills
of patients with multiple sclerosis in a cohort of patients with multiple
sclerosis in a single center in Tehran, Iran. Methods: One hundred and
forty-seven patients with multiple sclerosis with mean age of 33 years, mean
disease duration of 20.20 months, mean EDSS of 2.13, and F to M ratio of 76.5% over
23% were recruited for the purpose of this study. Cognitive function was
compared with healthy control subjects (n = 100). Depression was measured by
Beck Depression Inventory (BDI), fatigue was assessed using Fatigue Severity
Scale (FSS) and Modified Fatigue Impact Scale (MFIS), disability was evaluated
by Expanded Disability Status Scale (EDSS), and cognitive function was assessed
by Brief Repeatable Battery of Neuropsychological tests (BRB-N). All data were
analysed using Pearson correlation. Results: Age and disability level generally
correlated negatively and significantly with task performance, whereas a higher
level of education was associated with better task performance. While the
correlation between BDI, FSS, and MIFS was significantly positive, BDI was
negatively correlated with the two subscales of BRB, namely PASAT and WLG.
Higher levels of depression in patients with MS are associated with lower
cognitive performance in tasks requiring higher-order working memory (WM)
processes. FSS showed the strongest negative correlation score with BRB,
however, the same parameter displayed significant positive correlation with
MFIS. Moreover, the global EDSS scores were negatively correlated with BRB.
Relative to controls, cognitive performance of MS patients was deficient in all
BRB-N measures except Symbol Digit Modalities Test which is a measure of
attention and processing speed. Conclusions: Depression, fatigue, and
disability (the most common problems observed in MS patients) are clearly
related with cognitive impairment in MS patients. Also, MS patients exhibit a
pattern of cognitive impairment running across the studied cognitive domains in
comparison to healthy subjects.