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Parasomnias

Parasomnias are a group of sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorders marked by unusual actions, activities, or physiological events that occur during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep or sleep-wake transitions. Parasomnias are divided according to the sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep phase in which the symptoms occur, either rapid eye movement (REM) or non-REM ( NREM NREM Physiology of Sleep). Symptoms may include simple or complex abnormal movements, such as sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep talking, sleepwalking, sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep terrors, and dream enactment, or emotions, dreams, and autonomic activity. Diagnosis involves a thorough history taking from the individual and anyone who witnesses the movements or behaviors. In some cases, polysomnography Polysomnography Simultaneous and continuous monitoring of several parameters during sleep to study normal and abnormal sleep. The study includes monitoring of brain waves, to assess sleep stages, and other physiological variables such as breathing, eye movements, and blood oxygen levels which exhibit a disrupted pattern with sleep disturbances. Physiology of Sleep is required, especially if comorbid sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorders are suspected. Some conditions resolve over time without any treatment. For those that require intervention, options include lifestyle or risk modifications, different forms of therapy, and medications. Choice of management is affected by individual preferences.

Last updated: Jul 18, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

Parasomnias are abnormal behaviors, actions, or activities occurring during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep.

Classification

Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorders are generally divided into the following groups:

  • Parasomnias, which have subtypes according to each sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep stage:
    • Non-rapid eye movement ( NREM NREM Physiology of Sleep) sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep arousal disorders: 
      • Sleepwalking (somnambulism)
      • Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep terrors
      • Sleep-related eating disorders 
      • Confusional arousals
      • Sleep-related abnormal sexual behavior
    • Rapid eye movement (REM) sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep arousal disorders:
      • REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep behavior disorder (RBD) 
      • Nightmare disorder
  • Dyssomnias, which are abnormalities in the amount, quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement, or timing of sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep; the subtypes are:
    • Insomnia Insomnia Insomnia is a sleep disorder characterized by difficulty in the initiation, maintenance, and consolidation of sleep, leading to impairment of function. Patients may exhibit symptoms such as difficulty falling asleep, disrupted sleep, trouble going back to sleep, early awakenings, and feeling tired upon waking. Insomnia disorder
    • Narcolepsy Narcolepsy Narcolepsy is a neurological sleep disorder marked by daytime sleepiness and associated with cataplexy, hypnagogic hallucinations, and sleep paralysis. There are 2 types of narcolepsy: type 1 is associated with cataplexy and type 2 has no association with cataplexy. Narcolepsy
    • Circadian rhythm Circadian Rhythm The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli. Cranial Nerve Palsies sleep-wake disorders
    • Sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea

Etiology and Epidemiology

Etiology

  • Theory on dissociation Dissociation Defense Mechanisms of states of consciousness consisting of wakefulness, NREM NREM Physiology of Sleep, REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep: combinations of these states → parasomnias
  • NREM-related disorders:
    • NREM NREM Physiology of Sleep generally exhibits instinctive actions, which would normally be inhibited in wakefulness. 
    • In NREM NREM Physiology of Sleep subtypes, there is an admixture of wakefulness and NREM NREM Physiology of Sleep.
    • Increased slow-wave sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep in NREM NREM Physiology of Sleep (difficult to arouse) noted, but there is potential for motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology capacity
    • Factors:
      • Genetic predisposition
      • Conditions (stress, sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep deprivation, fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever
      • Substances (alcohol, medications such as zolpidem are associated with sleep-related eating disorder) 
  • REM-related disorders:
    • Mix of wakefulness and elements of REM
    • Believed to have degeneration of cells involved in the normal REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep pathway 

Epidemiology

  • NREM NREM Physiology of Sleep sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorders are more common in a younger demographic whereas REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep disorders are more common in an older demographic.
  • REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep disorder is more common among men, especially in the older demographic.
  • Sleep-related eating disorder mostly occurs among women.
  • High prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency of RBD in those with Parkinson disease Parkinson disease Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease

Clinical Presentation and Diagnosis

Clinical features of NREM-related parasomnias

  • Sleepwalking:
    • Episodes of simple to complex movements
    • May include sitting in bed, walking, eating, going outdoors, and, in rare cases, violent behaviors
    • Difficult to arouse during episode (eyes might be open with a blank stare)
    • Failure to recall the episode (amnesia)
    • Episodes might end with individuals returning to bed or briefly awakening (confused and disoriented).
  • Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep terrors:
    • Marked by sudden arousals, beginning with screaming or crying
    • Associated with autonomic changes ( tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children, tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination, diaphoresis, mydriasis Mydriasis Dilation of pupils to greater than 6 mm combined with failure of the pupils to constrict when stimulated with light. This condition may occur due to injury of the pupillary fibers in the oculomotor nerve, in acute angle-closure glaucoma, and in adie syndrome. Glaucoma)
    • Difficult to arouse during episode (not responsive)
    • Amnesia or partial dream recollection afterwards
    • Episodes end with individuals returning to sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep.
    • Most common in children
  • Sleep-related eating disorder:
    • Recurring episodes of involuntary eating after being aroused from sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep
    • Possible partial awareness during the event
    • May have partial recollection of event
    • Criteria specify that episodes have to include the following:
      • Consuming toxic food, or
      • Engaging in potentially injurious behaviors while obtaining food, or 
      • Adverse health effects from chronic nighttime eating
  • Confusional arousals:
    • Mental confusion or disorientation Disorientation St. Louis Encephalitis Virus on awakening (from slow-wave sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep), usually lasting < 15 minutes
    • Awake individual but with reduced responsiveness
    • Typically without recall of event
  • Sleep-related abnormal sexual behavior (sexsomnia):
    • Can occur with obstructive sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea
    • Abnormal sexual behaviors (without awareness and typically without recall) can include:

Clinical features of REM-related parasomnias

  • RBD:
    • Dream-enacting behaviors include:
      • Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep talking or yelling
      • Limb jerking
      • Walking and/or running
      • Punching and/or other violent behaviors
    • Episodes of arousal during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep
    • Characterized by a lack of muscle atonia Atonia Flaccidity, no resistance to passive motion Neurological Examination during REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep 
    • With recollection of dream content 
    • Upon awakening, often alert but can be briefly disoriented
    • Presenting complaint is often made by the individual’s partner (reporting violent behaviors during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep resulting in injury to the partner).
    • Commonly seen in:
      • Elderly individuals 
      • Individuals taking certain medications (serotonergic antidepressants and beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers))
      • Those with neurodegenerative disorders ( Parkinson disease Parkinson disease Parkinson’s disease (PD) is a chronic, progressive neurodegenerative disorder. Although the cause is unknown, several genetic and environmental risk factors are currently being studied. Individuals present clinically with resting tremor, bradykinesia, rigidity, and postural instability. Parkinson’s Disease, multiple system atrophy Multiple System Atrophy A syndrome complex composed of three conditions which represent clinical variants of the same disease process: striatonigral degeneration; shy-drager syndrome; and the sporadic form of olivopontocerebellar atrophies. Clinical features include autonomic, cerebellar, and basal ganglia dysfunction. Pathologic examination reveals atrophy of the basal ganglia, cerebellum, pons, and medulla, with prominent loss of autonomic neurons in the brain stem and spinal cord. Atypical Parkinsonian Syndromes, and neurocognitive disorder with Lewy bodies Lewy bodies Intracytoplasmic, eosinophilic, round to elongated inclusions found in vacuoles of injured or fragmented neurons. The presence of lewy bodies is the histological marker of the degenerative changes in lewy body disease and parkinson disease but they may be seen in other neurological conditions. They are typically found in the substantia nigra and locus coeruleus but they are also seen in the basal forebrain, hypothalamic nuclei, and neocortex. Parkinson’s Disease)
  • Nightmare disorder:
    • Recurrent episodes of vivid dreams (with scary, negative themes)
    • Not associated with motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology activity or sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep injury
    • Episodes end with individuals awakening and recalling the unpleasant dream. 
    • Individual is fully alert upon awakening (no confusion or disorientation Disorientation St. Louis Encephalitis Virus).
    • Causes significant distress or impaired functioning
    • Not associated with medication or substance use

Diagnostic approach

  • NREM NREM Physiology of Sleep parasomnias can often be diagnosed from history taken from the individual or anyone who witnesses the movements or behaviors. 
  • Nightmare disorder is also a clinical diagnosis.
  • In conditions above, suspicion of comorbid sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorder (e.g., obstructive sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea ( OSA OSA Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea)) requires polysomnography Polysomnography Simultaneous and continuous monitoring of several parameters during sleep to study normal and abnormal sleep. The study includes monitoring of brain waves, to assess sleep stages, and other physiological variables such as breathing, eye movements, and blood oxygen levels which exhibit a disrupted pattern with sleep disturbances. Physiology of Sleep.
  • In RBD, detailed history is helpful, but video polysomnography Polysomnography Simultaneous and continuous monitoring of several parameters during sleep to study normal and abnormal sleep. The study includes monitoring of brain waves, to assess sleep stages, and other physiological variables such as breathing, eye movements, and blood oxygen levels which exhibit a disrupted pattern with sleep disturbances. Physiology of Sleep is required for a definitive diagnosis.

Management

  • Non-REM parasomnias:
    • Individuals with mild symptoms may benefit from behavioral therapy:
    • Risk factor modification (e.g., discontinue medication)
    • Ensure environmental safety (e.g., secure locks, remove dangerous objects)
    • Treat coexisting sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorders.
    • Refractory cases (frequent, persistent, and distressing) might benefit from a short course of benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines such as clonazepam Clonazepam An anticonvulsant used for several types of seizures, including myotonic or atonic seizures, photosensitive epilepsy, and absence seizures, although tolerance may develop. It is seldom effective in generalized tonic-clonic or partial seizures. The mechanism of action appears to involve the enhancement of gamma-aminobutyric acid receptor responses. Benzodiazepines
    • In addition, the following pharmacotherapy are options:
  • REM sleep REM sleep A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern eeg. It is usually associated with dreaming. Physiology of Sleep behavior disorder:
    • Risk factor modification
    • Ensure environmental safety around the individual (remove any dangerous objects near place of sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep).
    • Medications that might be helpful: 
      • Clonazepam Clonazepam An anticonvulsant used for several types of seizures, including myotonic or atonic seizures, photosensitive epilepsy, and absence seizures, although tolerance may develop. It is seldom effective in generalized tonic-clonic or partial seizures. The mechanism of action appears to involve the enhancement of gamma-aminobutyric acid receptor responses. Benzodiazepines is efficacious in 90% of individuals.
      • Melatonin 
  • Nightmare disorder:
    • Reassurance Reassurance Clinician–Patient Relationship might be enough.
    • Desensitization/imagery rehearsal therapy (IRT) involves:
      • Use of mental representation to modify the result of a recurrent nightmare
      • Writing down the improved outcome
      • Mentally repeating it in a relaxed state
    • Medications (e.g., prazosin Prazosin A selective adrenergic alpha-1 antagonist used in the treatment of heart failure; hypertension; pheochromocytoma; raynaud disease; prostatic hypertrophy; and urinary retention. Antiadrenergic Drugs, antidepressants) may be indicated if nightmare disorder is associated with PTSD PTSD Posttraumatic stress disorder is a psychiatric illness characterized by overwhelming stress and anxiety experienced after exposure to a life-threatening event. Symptoms last more than 1 month and involve re-experiencing the event as flashbacks or nightmares, avoiding reminders of the event, irritability, hyperarousal, and poor memory and concentration. Posttraumatic Stress Disorder (PTSD) or other psychiatric disorder(s).

Differential Diagnosis

  • Restless legs syndrome Restless legs syndrome Restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED), is marked by a severe urge to move the legs, and an unpleasant sensation only relieved by movement. Restless legs syndrome occurs after inactivity, especially during the evening and night, and is associated with sleep disturbance. Restless Legs Syndrome: marked by an overwhelming urge to move the legs, accompanied by unpleasant sensations, which are relieved by movement. Symptoms usually occur during the evening and cause sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disturbance. Individuals are aware of restless legs Restless legs A disorder characterized by aching or burning sensations in the lower and rarely the upper extremities that occur prior to sleep or may awaken the patient from sleep. Polyneuropathy causing distress, while they are not usually aware of parasomnias.
  • OSA OSA Obstructive sleep apnea (OSA) is a disorder characterized by recurrent obstruction of the upper airway during sleep, causing hypoxia and fragmented sleep. Obstructive sleep apnea is due to a partial or complete collapse of the upper airway and is associated with snoring, restlessness, sleep interruption, and daytime somnolence. Obstructive Sleep Apnea: episodic apnea, or cessation of breathing during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep, in which the period of apnea lasts for more than 10 seconds. Obstructive sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea is usually due to a partial or complete collapse of the upper airway Airway ABCDE Assessment and is associated with snoring, restlessness, daytime headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess, and somnolence. Obstructive sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea is much more prevalent than parasomnias and must be ruled out. 
  • Nocturnal seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures: should be excluded in individuals with suspected parasomnias. Symptoms of nocturnal seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures include repetitive stereotypical movements (tonic or dystonic), occurring at any time during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep. Episodes are usually short in duration (≤ 30 seconds).

References

  1. Fariba, K., Tadi, P. (2021). Parasomnias. StatPearls. Treasure Island (FL): StatPearls Publishing; https://www.ncbi.nlm.nih.gov/books/NBK560524/
  2. Foldvary-Schaefer, N. (2020). Disorders of arousal from non-rapid eye movement sleep in adults. UpToDate. Retrieved June 5, 2021, from https://www.uptodate.com/contents/disorders-of-arousal-from-non-rapid-eye-movement-sleep-in-adults
  3. Ganti, L., Kaufman, M., Blitzstein, S. (2016). Sleep-wake disorders. First Aid for the Psychiatry Clerkship, (4th ed.), pages 166–168. McGraw-Hill.
  4. Judd, B. (2020). Classification of sleep disorders. UpToDate. Retrieved March 28, 2021, from https://www.uptodate.com/contents/classification-of-sleep-disorders?search=Parasomnias
  5. Kotagal, S. (2021). Parasomnias of childhood, including sleepwalking. UpToDate. Retrieved June 4, 2021, from https://www.uptodate.com/contents/parasomnias-of-childhood-including-sleepwalking
  6. Kazaglis, L., Bornemann, M.A.C. (2006). Classification of Parasomnias. Curr Sleep Medicine Rep2, 45–52. https://doi.org/10.1007/s40675-016-0039-y
  7. Markov, D., Jaffe, F., & Doghramji, K. (2006). Update on parasomnias: a review for psychiatric practice. Psychiatry (Edgmont (Pa.: Township), 3(7), 69–76.
  8. Pressman, M.R. (2007). Factors that predispose, prime and precipitate NREM parasomnias in adults: clinical and forensic implications. Sleep Med Rev. 11(1): 5–30; discussion 31–3. https://pubmed.ncbi.nlm.nih.gov/17208473/
  9. Sadock, B. J., Sadock, V. A., & Ruiz, P. (2014). Kaplan and sadock’s synopsis of psychiatry: Behavioral sciences/clinical psychiatry (11th ed.). Chapter 16, Sleep-wake disorders, pages 533–563. Philadelphia, PA: Lippincott Williams and Wilkins.

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