The relationship of sleep disturbances and fatigue in multiple sclerosis.
BACKGROUND
Fatigue is experienced by most patients with multiple sclerosis (MS) and often is profoundly debilitating. No large-scale studies to our knowledge have examined circadian rhythm abnormalities in MS patients or the relationship of fatigue to circadian rhythms.


OBJECTIVE
To determine if patients with MS and fatigue have sleep disturbances or circadian rhythm abnormalities associated with fatigue.


METHODS
Case-control study.


METHODS
Washington University School of Medicine, St Louis, Mo.


METHODS
Fifteen patients with MS and fatigue were compared with 15 patients with MS without fatigue and 15 age- and sex-matched, healthy controls.


METHODS
Sleep disturbances and circadian rhythm abnormalities were quantitated by actigraphy, fatigue by the Fatigue Descriptive Scale, and excessive sleepiness by the Epworth Sleepiness scale (ESS).


RESULTS
Of the 15 fatigued patients with MS, 2 had delayed sleep phase, 10 had disrupted sleep, and 3 had normal sleep. One of the 15 nonfatigued MS patients had irregular sleep cycles, 2 others had disrupted sleep, and 12 had normal sleep. All 15 of the healthy controls had normal sleep. Nine patients with MS and fatigue scored 10 or higher on the ESS, suggesting excessive daytime sleepiness. Only 2 patients with MS without fatigue scored higher than 10 on the ESS. None of the healthy controls were fatigued, and 14 were not excessively sleepy. A relationship was found between fatigue and abnormal sleep cycles or disrupted sleep (Fisher exact test, P =.003). There was also a relationship between subjective excessive daytime sleepiness and fatigue in MS patients (P =.02).


CONCLUSIONS
There is a significant correlation between fatigue in MS patients and disrupted sleep or abnormal sleep cycles.
Attarian
Hrayr P
HP
Department of Neurology, University of Vermont, Burlington 05401, USA. hrayr.attarian@vtmednet.org
Brown
Kelly M
KM
Duntley
Stephen P
SP
Carter
Jewell D
JD
Cross
Anne H
AH
D000328:Adult; D016022:Case-Control Studies; D002940:Circadian Rhythm / Q000502:physiology; D005221:Fatigue / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000175:diagnosis* / Q000503:physiopathology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000175:diagnosis* / Q000503:physiopathology; D020178:Sleep Disorders, Circadian Rhythm / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D013223:Statistics as Topic; D013493:Suprachiasmatic Nucleus / Q000503:physiopathology