Overview of Idiopathic REM Sleep Behavior Disorder

Abstract

REM sleep behavior disorder (RBD) is a REM sleep-related parasomnia characterized by action of dream content, which is often an aggressive or terrible nightmare. Because of the self-defense movements and behaviors in dreams, sleep-talking (e.g., yelling and screaming) and violent movements of the arms and legs may injure the patient or bed partner. Idiopathic or isolated RBD that develops after middle age may progress to neurodegenerative diseases, such as Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy, in half of the patients after 10 years. The development of a method that can accurately diagnose RBD by polysomnography may help to identify patients at high short-term risk of developing α-synucleinopathies. Such patients may be enrolled in trials of disease-modifying therapy. Several techniques for the early diagnosis of α-synucleinopathies are under development for clinical use and await application in clinical trials of candidate therapies.