Night-to-night variability of muscle tone, movements, and vocalizations in patients with REM sleep behavior disorder.

Objectives: The video-polysomnographic criteria of REM sleep behavior disorder (RBD) have not been well described. We evaluated the between-night reproducibility of phasic and tonic enhanced muscle activity during REM sleep as well as the associated behaviors and vocalizations of the patients.

Methods: Fifteen patients with clinical RBD underwent two consecutive video-polysomnographies.