Sleep structure and sleepiness in chronic fatigue syndrome with or without coexisting fibromyalgia

Fumiharu Togo¹^,2 , Benjamin H Natelson¹ , Neil S Cherniack³ , Jennifer FitzGibbons¹ , Carmen Garcon¹ and David M Rapoport⁴

¹Pain and Fatigue Study Center, Department of Neurosciences, University of Medicine and Dentistry of New Jersey (UMDNJ)-New Jersey Medical School, 30 Bergen Street, Newark, NJ 07103, USA

²Department of Work Stress Control, Japan National Institute of Occupational Safety and Health, 6-21-1 Nagao, Tama-ku, Kawasaki, 214-8585, Japan

³Pain and Fatigue Study Center, Department of Medicine, UMDNJ-New Jersey Medical School, 30 Bergen Street, Newark, NJ 07103, USA

⁴Department of Medicine, Division of Pulmonary and Critical Care Medicine, New York University School of Medicine, 462 First Avenue, New York, NY 10016, USA

author email corresponding author email

Arthritis Research & Therapy 2008, 10:R56doi:10.1186/ar2425


Published:	13 May 2008

Abstract

Introduction

We evaluated polysomnograms of chronic fatigue syndrome (CFS) patients with and without fibromyalgia to determine whether patients in either group had elevated rates of sleep-disturbed breathing (obstructive sleep apnea or upper airway resistance syndrome) or periodic leg movement disorder. We also determined whether feelings of unrefreshing sleep were associated with differences in sleep architecture from normal.

Methods

We compared sleep structures and subjective scores on visual analog scales for sleepiness and fatigue in CFS patients with or without coexisting fibromyalgia (n = 12 and 14, respectively) with 26 healthy subjects. None had current major depressive disorder, and all were studied at the same menstrual phase.

Results

CFS patients had significant differences in polysomnograpic findings from healthy controls and felt sleepier and more fatigued than controls after a night's sleep. CFS patients as a group had less total sleep time, lower sleep efficiency, and less rapid eye movement sleep than controls. A possible explanation for the unrefreshing quality of sleep in CFS patients was revealed by stratification of patients into those who reported more or less sleepiness after a night's sleep (a.m. sleepier or a.m. less sleepy, respectively). Those in the sleepier group reported that sleep did not improve their symptoms and had poorer sleep efficiencies and shorter runs of sleep than both controls and patients in the less sleepy group; patients in the less sleepy group reported reduced fatigue and pain after sleep and had relatively normal sleep structures. This difference in sleep effects was due primarily to a decrease in the length of periods of uninterrupted sleep in the a.m. sleepier group.

Conclusion

CFS patients had significant differences in polysomnographic findings from healthy controls and felt sleepier and more fatigued than controls after a night's sleep. This difference was due neither to diagnosable sleep disorders nor to coexisting fibromyalgia but primarily to a decrease in the length of periods of uninterrupted sleep in the patients with more sleepiness in the morning than on the night before. This sleep disruption may explain the overwhelming fatigue, report of unrefreshing sleep, and pain in this subgroup of patients.