title: Fatigue in multiple sclerosis and its relationship to depression and neurologic disability.
abstract: We studied multiple sclerosis fatigue (MSF) and its relationship to depression and disability. Seventy-one patients [50 relapsing-remitting, 21 secondary progressive] were grouped by Fatigue Severity Scale (FSS) into MS-fatigue (MSF) (FSS>/=5; n=46) or MS-nonfatigue (MSNF) (FSS</=4; n=20). Forty-one patients were grouped into MS-depression (MSD) (n=15) or MS-nondepression (MSND) (n=26) by interview. Higher expanded disability status scale (EDSS) scores were noted in MSF than MSNF patients (P=0.0003); EDSS scores correlated with FSS scores (rho=0.43, P=0.003). However, fatigue was present in 58% (n=29) of relapsing-remitting patients and in 52% (n=26) of patients with mild physical disability (EDSS<3.5). Hamilton/Beck depression severity scores were higher in MSF than MSNF patients and correlated with FSS scores (P<0.05). MSD had higher FSS scores than MSND patients (P=0.008). After controlling for EDSS, depression severity continued to correlate with FSS scores (rho=0.37, P=0.02). After controlling for depression, FSS scores no longer correlated with EDSS scores (rho=0.27, P=0.09). Thus, MSF is independent of physical disability, but is associated with depression, suggesting that common mechanisms play a role in MSF and MSD including psychological factors or brain lesions in specific neuroanatomic pathways. Further study is warranted to determine if antidepressant medications improve fatigue in MS.
authors.affiliation: Dent Neurologic Institute, Kaleida Health-Millard Fillmore Hospital, State University of New York at Buffalo School of Medicine and Biomedical Sciences, USA.
authors.forename: R
authors.initials: R
authors.lastname: Bakshi
authors.forename: Z A
authors.initials: ZA
authors.lastname: Shaikh
authors.forename: R S
authors.initials: RS
authors.lastname: Miletich
authors.forename: D
authors.initials: D
authors.lastname: Czarnecki
authors.forename: J
authors.initials: J
authors.lastname: Dmochowski
authors.forename: K
authors.initials: K
authors.lastname: Henschel
authors.forename: V
authors.initials: V
authors.lastname: Janardhan
authors.forename: N
authors.initials: N
authors.lastname: Dubey
authors.forename: P R
authors.initials: PR
authors.lastname: Kinkel
mesh_terms: D000328:Adult; D003863:Depression / Q000209:etiology* / Q000523:psychology; D006233:Persons with Disabilities / Q000523:psychology*; D005221:Fatigue / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D009420:Nervous System / Q000503:physiopathology*; D012720:Severity of Illness Index