Parasomnias in Narcolepsy with Cataplexy

Abstract

Narcolepsy with cataplexy is a disabling disorder characterized by excessive daytime sleepiness (EDS) and abnormal rapid eye movement (REM) sleep manifestations including cataplexy (sudden loss of muscle tone triggered by strong emotions), sleep paralysis, hypnagogic hallucinations, and sleep-onset REM periods. Parasomnias are undesirable physical events or experiences that occur during entry into sleep, within sleep, or during arousals from sleep. Bed partners may complain or note concern over frequent movements during the sleep period that may lead to severe injuries. Parasomnias are classified according to the type of sleep in which they occur, namely, non-rapid eye movement (NREM) sleep parasomnias including mainly sleep terrors and sleepwalking, and rapid eye movement (REM) sleep parasomnias including mainly REM sleep behavior disorder, recurrent isolated sleep paralysis, and nightmares. Other parasomnias including sleep enuresis, sleep-related groaning, exploding head syndrome, sleep-related hallucinations, and sleep-related eating disorder (SRED) were without clear related stage. The natural history of age at onset, time of night of the events, characteristics of the behavior, memory for the events, and family history are important in distinguishing the parasomnia etiology. Only few studies have focused on the frequency of NREM and REM parasomnias in narcolepsy. Even if clearly underestimated and not included in the tetrad narcolepsy symptoms, the parasomnia frequencies in both NREM and REM sleep were higher in narcolepsy compared to that in the general population. Typically, nighttime sleep of narcoleptics was interrupted with several and long awakenings, and abnormal movements or behaviors during REM or NREM sleep, which may also be severe. (PsycINFO Database Record (c) 2016 APA, all rights reserved)