Rapid Eye Movement Sleep-related Parasomnias.

Among the rapid eye movement (REM) sleep-related parasomnias, the most common and important disorder for which patients present is REM sleep behavior disorder (RBD). Rapid eye movement sleep behavior disorder is often undiagnosed for many years, despite the sometimes bizarre and harmful behaviors involved. Complete evaluation and accurate diagnosis are essential for proper management. This includes medical, sleep/wake, psychiatric, and neurologic histories. Although they may raise feelings of guilt or shame, questions related to sexual and violent behaviors should be directed towards the identified patient as well as their bed partners. Objective studies should include nocturnal polysomnogram with audiovisual monitoring of behavior, electromyography (EMG) of all limbs, and seizure montage. Brain imaging, clinical electroencephalogram (EEG), neuropsychometric testing, and actigraphy may be used adjunctively. Clinicians should have a high index of suspicion for other neurologic conditions, especially neurodegenerative disorders and narcolepsy, because many patients with RBD have these conditions. Rapid eye movement sleep behavior disorder may actually precede symptoms and signs associated with other neurologic disorders, so close follow-up is recommended. Medications that may be causing or exacerbating RBD should be withdrawn, if possible. Clonazepam is very effective in reducing the symptoms of RBD. This treatment is generally well tolerated and may be used long-term. Discontinuation of clonazepam usually leads to relapse of symptoms. Safety-related issues should be discussed with patients and their families.