Sleep Med Psychophysiol.  2005 Jun;12(1):58-63.

Comparison of Clinical Characteristics and Polysomnographic Findings between REM Sleep Behavior Disorder with and without Associated Central Nervous System Disorders

• Lee YJ
• Jeong DU

Abstract

OBJECTIVES
REM sleep behavior disorder (RBD), characterized by excessive motor activity during REM sleep, is associated with loss of muscle atonia. In recent years, it has been reported that RBD has high co-morbidity with CNS disorders (especially, Parkinson's disease, dementia, multiple system atrophy, etc.). We aimed to assess differences in clinical and polysomnographic findings among RBD patients, depending on the presence or absence of central nervous system (CNS) disorders. METHODS: The medical records and polysomnographic data of 81 patients who had been diagnosed as having RBD were reviewed. The patients were classified into two groups: associated RBD (aRBD, i.e., with a clinical history and/or brain MRI evidence of CNS disorder) and idiopathic RBD (iRBD, i.e., without a clinical history and/or brain MRI evidence of CNS disorder) groups. Twenty-one patients (25.9%) belonged to the aRBD group and 60 patients (74.1%) belonged to the iRBD group. The clinical characteristics and polysomnographic findings of the two groups were compared. RESULTS: Periodic limb movement disorder (PLMD), i.e., PLMI (periodic limb movement index) > 5, was observed more frequently in the aRBD group than in the iRBD group (p< 0.001, Fisher's exact test). Also, obstructive sleep apnea syndrome (OSAS), i.e., RDI (respiratory disturbance index) > 5, was found more frequently in the aRBD group (p=0.0042, Fisher's exact test). The percentages for slow wave sleep and sleep efficiency were significantly lower in the aRBD group than in the iRBD group. CONCLUSION: We found that 1 out of 4 RBD patients had associated CNS disorders, warranting more careful neurological evaluation and follow-up in this category of RBD. In this category of RBD patients, we also found more frequent PLMD and OSAS. These patients were also found to have lower slow wave sleep and sleep efficiency. In summary, RBD patients with associated CNS disorders suffer from more disturbed sleep than those without them.

Keyword

REM sleep behavior disorder; CNS disorder; Sleep disturbance

MeSH Terms

Brain
Central Nervous System Diseases*
Central Nervous System*
Dementia
Extremities
Humans
Magnetic Resonance Imaging
Medical Records
Motor Activity
Multiple System Atrophy
Nocturnal Myoclonus Syndrome
Parkinson Disease
REM Sleep Behavior Disorder*
Sleep Apnea, Obstructive
Sleep, REM*