Disorders That Disrupt Sleep (Parasomnias)
Disorders That Disrupt Sleep (Parasomnias) Overview
Parasomnias are disruptive sleep-related disorders. They are characterized by undesirable physical or verbal behaviors or experiences. Parasomnias occur in association with sleep, specific stages of sleep (see Sleep: Understanding the Basics), or sleep-awake transition phases.
Parasomnias may be divided into the following categories:
The 4 parasomnia sleep disorders that are discussed in this article are nightmare disorder, sleep terror disorder, sleepwalking disorder (somnambulism), and REM sleep behavior disorder. Two additional disorders classified as Sleep Related Movement Disorders are restless legs syndrome (RLS), and periodic limb movement disorder (PLMD).
Nightmare disorder is also called dream anxiety attack. Most patients with nightmare disorder are children. Nightmares are frightening dreams that occur during REM sleep and are associated with an increase in heart rate (tachycardia), an increase in the rate of breathing (tachypnea), profuse sweating, and arousal. Most of the time, the patient remembers the scary dream in detail and responds to soothing and comforting by a parent or caregiver.
Sleep terror disorder
Sleep terror disorder is characterized by extreme panic and a sudden, loud, terrified scream during sleep, which may be followed by physical activities such as hitting objects or moving in and out of the bedroom. Persons with this disorder can injure themselves. Sleep terror is a disorder of arousal that primarily occurs during stage III of NREM sleep. Subsequent recollection of the episodes either does not occur or is partial. The event is often more stressful for the parent or bystander since the individual is technically still asleep.
Patients with sleepwalking disorder show complex automatic behaviors, such as wandering aimlessly, carrying objects without any purpose, going outdoors, and performing other activities of varying complexity and duration (even driving). Persons affected with the disorder usually have their eyes wide open in a stare. They may mumble; however, communication with a person who is sleepwalking is usually poor or impossible. This disorder occurs in the slow-wave stages of NREM sleep. Safety proofing the sleep environment is an important consideration. Alarms on doors and windows and gates on stairs can be placed if appropriate.
REM sleep behavior disorder
Patients with REM sleep behavior disorder (RBD) act out distinctly altered dreams that are vivid, intense, action-packed, and violent. Dream-enacting behaviors include talking, yelling, punching, kicking, sitting, jumping out of bed, arm flailing, and grabbing. An acute form may occur during withdrawal from ethanol or sedative-hypnotic drugs. See REM Sleep Behavior Disorder.
Restless legs syndrome and periodic limb movement disorder
Restless legs syndrome and periodic limb movement disorder are classified as Sleep Related Movement Disorders. They are common disorders that often may coexist. The primary symptom of restless legs syndrome is insomnia (inability to sleep), whereas periodic leg movement disorder is a well-recognized cause of excessive daytime sleepiness. Nearly all persons with restless legs syndrome have periodic limb movements, and only few persons with periodic limb movement disorder also have restless legs syndrome.
Medically Reviewed by a Doctor on 7/25/2014
Sat Sharma, MD, FRCPC, FCCP
Anthony M Murro, MD
Mary L Windle, PharmD
Stephen Berman, MD, PhD
Must Read Articles Related to Disorders That Disrupt Sleep (Parasomnias)