Somnambulism (sleepwalking)

Awake or Sleeping? Maybe Both… A Review of Sleep-Related Dissociative States

Recent studies have begun to understand sleep not only as a whole-brain process but also as a complex local phenomenon controlled by specific neurotransmitters that act in different neural networks, which is called "local sleep". Moreover, the basic states of human consciousness-wakefulness, sleep onset (N1), light sleep (N2), deep sleep (N3), and rapid eye movement (REM) sleep-can concurrently appear, which may result in different sleep-related dissociative states. In this article, we classify these sleep-related dissociative states into physiological, pathological, and altered states of consciousness. Physiological states are daydreaming, lucid dreaming, and false awakenings. Pathological states include sleep paralysis, sleepwalking, and REM sleep behavior disorder. Altered states are hypnosis, anesthesia, and psychedelics. We review the neurophysiology and phenomenology of these sleep-related dissociative states of consciousness and update them with recent studies. We conclude that these sleep-related dissociative states have a significant basic and clinical impact since their study contributes to the understanding of consciousness and the proper treatment of neuropsychiatric diseases.

Diagnosis and Management of NREM Sleep Parasomnias in Children and Adults

Non-rapid eye movement (NREM) sleep parasomnias are recurrent abnormal behaviors emerging as incomplete arousals out of NREM sleep. Mounting evidence on NREM sleep parasomnias calls for an update of clinical and therapeutical strategies. In the current review, we summarize the state of the art and provide the necessary background to stimulate a critical revision of diagnostic criteria of disorders of arousal (DoA), the most common NREM sleep parasomnia. In particular, we highlight the poor sensitivity of the diagnostic items related to amnesia and absence of conscious experiences during DoA episodes, encourage the role of video-polysomnography and home-video recordings in the diagnostic and treatment work-up, and suggest three levels of diagnostic certainty based on clinical and objective findings. Furthermore, we highlight current gaps of knowledge that prevent the definition of standard guidelines and future research avenues.

Sleep-related motor disorders

Sleep-related motor disorders include non-rapid-eye movement (NREM) sleep parasomnias, rapid-eye movement (REM), sleep parasomnias including REM sleep behavior disorder (RBD), isolated motor phenomena in sleep, and periodic limb movement disorder. Restless legs syndrome (RLS) occurs while awake but is closely related to sleep and has a circadian pattern. The pontine sublaterodorsal tegmental nucleus has an important role in aligning motor control with sleep states, and dysfunction in this region can explain motor activities including cataplexy and loss of REM atonia seen in REM sleep behavior disorder. This chapter begins with a review of motor control in sleep. The rest of the chapter summarizes the clinical presentation, epidemiology, differential and treatment of NREM, REM, and isolated sleep-related motor disorders as well as restless legs syndrome.

Drugs Used in Parasomnia

Parasomnias, especially disorders of arousal during childhood, are often relatively benign and transitory and do not usually require a pharmacologic therapy. A relevant aspect in both nonrapid eye movement and rapid eye movement parasomnia treatment is to prevent sleep-related injuries by maintaining a safe environment. Physicians should always evaluate the possible presence of favoring and precipitating factors (sleep disorders and drugs). A pharmacologic treatment may be indicated in case of frequent, troublesome, or particularly dangerous events. The aim of this article is to review current available evidence on pharmacologic treatment of different forms of parasomnia.

Olanzapine-Related Somnambulism: A Systematic Review of Literature and a Case Report of Anorexia Nervosa

BACKGROUND

Somnambulism, or sleepwalking (SW), is one of the most common forms of arousal parasomnias. It is characterized by different complex motor behaviors leading to unwanted movements in bed or walking during sleep. It can be the consequence of psychological stress, abnormal breathing during sleep, high fever, or drug adverse effects. There is evidence of an association between antipsychotic treatment, including olanzapine, and SW.

METHODS

We present the case of a patient experiencing treatment-resistant anorexia nervosa whose somnambulism re-exacerbated after the addition of a low dose of olanzapine, following the CARE (CAse REport) Statement and Checklist. We also conducted a systematic review of the literature on olanzapine-induced somnambulism following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, PsychINFO, and the Cochrane Library databases were independently reviewed up to January 2021 for articles reporting olanzapine-related somnambulism cases, without language or time restriction.

RESULTS

We describe a case of somnambulism in a patient initially admitted to our hospital for anorexia nervosa and treated with a low dose of olanzapine. This is the first case of SW induced by olanzapine in eating disorders to be reported. Up-to-date olanzapine-related somnambulism was described in 8 patients experiencing psychiatric disorders (ie, schizophrenia and bipolar disorder).

CONCLUSIONS

To provide a reliable estimate of incidence and prevalence for olanzapine-related somnambulism, large-scale, pharmacovigilance studies are required, to allow for comparisons of overall clinical characteristics, outcomes, including time to recovery, between different treatment options. Clinician awareness should be enhanced, and attention should be given to such infrequent adverse effects associated with antipsychotics.

Drugs Used in Parasomnia

Patient education and behavioral management represent the first treatment approaches to the patient with parasomnia, especially in case of disorders of arousal (DOA). A pharmacologic treatment of DOA may be useful when episodes are frequent and persist despite resolution of predisposing factors, are associated with a high risk of injury, or cause significant impairment, such as excessive sleepiness. Approved drugs for DOA are still lacking. The most commonly used medications are benzodiazepines and antidepressants. The pharmacologic treatment of rapid eye movement sleep behavior disorder is symptomatic, and the most commonly used drugs are clonazepam and melatonin.

Sleep-walking a rarest side effect of zolpidem

A 46-years-old male, with past history of road traffic accident and with no current/past history of substance abuse and no family history of sleep-walking, took zolpidem 10 mg without any prescription and after few days, the patient's son noticed the patient waking up in the middle of night and walking into their room with a staring expression and some incoherent speech. The patient had no memory of this event in the morning. This sleep-walking episode was attributed to zolpidem, as no medication change was made besides new start of zolpidem and the patient had no history of such episodes in the past. Zolpidem treatment was stopped, and since then, no further complaints of sleep-walking were reported.

Sleep-disordered breathing

PURPOSE OF REVIEW

This article introduces readers to the clinical presentation, diagnosis, and treatment of sleep-disordered breathing and reviews the associated risk factors and health consequences.

RECENT FINDINGS

Sleep-disordered breathing is associated with significant impairments in daytime alertness and cognitive function as well as adverse health outcomes. The initial treatment of choice is positive airway pressure. Improvements in technology and mask delivery systems have helped to make this treatment more comfortable and convenient for many patients.

SUMMARY

Sleep-disordered breathing, particularly in the form of obstructive sleep apnea, is highly prevalent in the general population and has important implications for neurology patients. Sleep-disordered breathing is characterized by repetitive periods of cessation in breathing, termed apneas, or reductions in the amplitude of a breath, known as hypopneas, that occur during sleep. These events are frequently associated with fragmentation of sleep, declines in oxygen saturation, and sympathetic nervous system activation with heart rate and blood pressure elevation. Obstructive sleep apnea, which represents cessation of airflow, develops because of factors such as anatomic obstruction of the upper airway related to obesity, excess tissue bulk in the pharynx, and changes in muscle tone and nerve activity during sleep. Central sleep apnea represents cessation of airflow along with absence or significant reduction in respiratory effort during sleep and is more commonly found in the setting of congestive heart failure, neurologic disorders, or cardiopulmonary disease.

Sleep medicine pharmacotherapeutics overview: today, tomorrow, and the future (part 2: hypersomnia, parasomnia, and movement disorders)

Over the past 10 years, significant strides have been made in therapeutics for sleep disorders. In this second installment of a two-part review series, we discuss the current evidence surrounding the mechanisms of actions, indications, efficacy, and adverse side effects associated with the current over-the-counter and pharmacotherapeutics for hypersomnia, parasomnias, and movement disorders of sleep.

Biperiden for treatment of somnambulism in adolescents and adults with or without epilepsy: clinical observations

BACKGROUND

Sleepwalking in adolescents and adults may lead to serious injuries and require treatment. Anecdotal treatment recommendations include benzodiazepines (which also work in focal seizures of the frontal lobe that are an important differential diagnosis), imipramine and amitriptyline.

METHODS

We assessed in a follow-up study of 4 years (medium, range: 2-7 years) the usefulness of the antiparkinsonian drug biperiden (Akineton©), an acetylcholine antagonist with high affinity for muscarinic M1-type receptors, in four consecutive cases of arousal disorder with sleepwalking and confusional behavior in adolescents and adults with or without epilepsy who did not respond to diazepam, clonazepam or amitriptyline.

FINDINGS

The adjunctive use of biperiden was associated with reduction or remission of sleepwalking episodes in four consecutive treatment-refractory cases of arousal disorder with sleepwalking and confusional behavior. In contrast, biperiden showed no effect in a patient with REM behavioral disorder.

INTERPRETATION

Although our observations do not and cannot establish the efficacy or safety of biperiden, it may be useful to consider biperiden for treatment of sleepwalking, if needed. A putative cholinergic mechanism of arousal disorders, including sleepwalking, provides a reasonable hypothesis why the anticholinergic agent biperiden might work. Evidence for efficacy and safety from randomized controlled trials is needed to confirm our preliminary observations.

Sleep and violence

OPINION STATEMENT

Treatment of violent behaviors in sleep depends on the underlying condition and a correct identification of the causative disorder is mandatory. After eliminating possible precipitating factors, pharmacological treatment is often required to control violent sleep behaviors. Although no drugs are specifically approved for the treatment of parasomnias and placebo-controlled trials are lacking in these patient populations, clonazepam is considered the drug of choice in the management of both Non-REM and REM parasomnias. Benzodiazepines may cause unwanted side effects especially in older individuals and tolerance is sometime observed. Melatonin and pramipexole may represent alternative options in REM sleep behavior disorder. Hypnosis therapy may be considered in arousal disorders when pharmacological treatment is contraindicated or ineffective. Management of nocturnal frontal lobe epilepsy include a first-step pharmacological approach with antiepileptic drugs (eg, carbamazepine, oxcarbazepine or other drugs effective on partial seizures), but surgical options may be considered in drug refractory patients. The published evidence for the efficacy of various treatments relies mostly upon case series or case reports.

Desensitization of GABAergic receptors as a mechanism of zolpidem-induced somnambulism

Sleepwalking is a frequently reported side effect of zolpidem which is a short-acting hypnotic drug potentiating activity of GABA(A) receptors. Paradoxically, the most commonly used medications for somnambulism are benzodiazepines, especially clonazepam, which also potentiate activity of GABA(A) receptors. It is proposed that zolpidem-induced sleepwalking can be explained by the desensitization of GABAergic receptors located on serotonergic neurons. According to the proposed model, the delay between desensitization of GABA receptors and a compensatory decrease in serotonin release constitutes the time window for parasomnias. The occurrence of sleepwalking depends on individual differences in receptor desensitization, autoregulation of serotonin release and drug pharmacokinetics. The proposed mechanism of interaction between GABAergic and serotonergic systems can be also relevant for zolpidem abuse and zolpidem-induced hallucinations. It is therefore suggested that special care should be taken when zolpidem is used in patients taking at the same time selective serotonin reuptake inhibitors.

Treatment options for parasomnias

Parasomnias are undesirable physical or experiential events that occur in and around sleep. Treatments include reassurance in some cases, various forms of cognitive-behavioral therapy (CBT), and pharmacologic agents. Cognitive restructuring, imagery rehearsal, relaxation, hypnosis, desensitization, and anticipatory awakenings are some of the common CBT and nonpharmacologic interventions. Medications that are used belong to a wide variety of pharmacologic classes, such as alpha-blockers (prazosin), tricyclic antidepressants (imipramine and clomipramine), selective serotonin reuptake inhibitors, benzodiazepines (diazepam and clonazepam), anticonvulsants (topiramate and gabapentin), desmopressin acetate, and anticholinergic agents (oxybutynin and tolterodine). Data on efficacy are only available from randomized trials on CBT and prazosin for nightmares and on pharmacologic and alarm therapy for enuresis. No large-scale randomized trials are available to assess the efficacy of the other treatments, and most data come from anecdotal case reports, case series, or small open-label trials.

[Disturbances of slow-wave sleep and psychiatric disorders]

Slow-wave sleep is defined as sleep stages 3 and 4 that characteristically show slow delta EEG activity during polysomnography. The percentage of slow-wave sleep normally declines with age. Sleep disorders are a common symptom of many psychiatric disorders. In polysomnographic recordings they mostly manifest as disturbances of sleep continuity. In some disorders changes in REM sleep are also found. A reduction of slow-wave sleep has most often been described in patients with depression and addictive disorders. More recent research implicates slow-wave sleep as an important factor in memory consolidation, especially the contents of declarative memory. Psychotropic drugs influence sleep in different ways. Hypnotic substances can reduce the deep sleep stages (e.g. benzodiazepines), whereas 5-HT2C antagonists increase the percentage of slow-wave sleep. Whether a selective impairment/alteration of slow-wave sleep is clinically relevant has not yet been proved.

New onset somnambulism associated with different dosage of mirtazapine: a case report

Somnambulism consists of variously complex behaviors that may result in harm to self or to others. Many different medications have been reported to induce somnambulism, and a few of them are newer antidepressants. A 40-year-old woman with history of major depression who experienced new onset somnambulism for successive 3 nights, whereas the antidepressant mirtazapine was increased from 30 to 45 mg/d. The notable and complex sleepwalking symptoms terminated dramatically on the first night after withdrawal of mirtazapine. There is clearly a cause-and-effect relationship between the treatment of higher-dosage mirtazapine and development of somnambulism. It might be related to the different affinities to 5-hydroxytryptamine 2 (5-HT(2)) and H(1) receptors at different dosages of mirtazapine, which explain the patient experiencing sleepwalking episodes exclusively at higher doses of mirtazapine. Clinical physicians should be aware of this adverse effect and taper or discontinue the regimen if sleepwalking develops.

Sexsomnia: an uncommon variety of parasomnia

Sexsomnia is considered a particular form of parasomnia characterized by atypical sexual behaviour during sleep. Only a few cases have been reported in the literature. We describe here two cases of sexsomnia that took place in adult women whose personal history was remarkable for traumatic sexual psychological stress during childhood. In addition, the first patient had a medical history of alcoholism during adolescence and current sleepwalking. In the second patient, drug consumption was reported during adolescence, and psychiatric assessment found a major depressive disorder. Neurological examination was normal for both patients. The sexual behaviour was reported by the bed partner because of total amnesia of the event by the patients. Events included moaning, vocalizations with dirty talk, masturbation, sexual assault, and sexual intercourse. The behaviour was harmful for the bed partner in the second case. For both patients, electroencephalogram and brain magnetic resonance imaging were normal whereas nocturnal polysomnography recordings revealed several abrupt and spontaneous arousals from slow-wave sleep. Patients were successfully treated by serotonin reuptake inhibitors. Our observations underline the fact that efforts need to be made to increase awareness of the issue of sexsomnia, in order to identify patients suffering from this atypical parasomnia, which can be associated with adverse psychological consequences and serious medico-legal issues.

Treatments for somnambulism in adults: assessing the evidence

Somnambulism, or sleepwalking, is a parasomnia of non-rapid eye movement (NREM) sleep where movement behaviours usually confined to wakefulness are displayed during sleep. Generally, if sleepwalking is causing distress or danger in spite of safety measures, medical or psychological treatment is indicated. Clinicians will need to assess the evidence for treatment options. MEDLINE, EMBASE, PsycINFO and the Ovid Evidence-Based Medicine Reviews (EBM) multifile databases were searched. No properly powered rigorous controlled trials were found for treatment of sleepwalking in adults. Seven reports described small trials with some kind of control arm, or retrospective case series which included 30 or more patients. With no high quality evidence to underpin recommendations for treatments of somnambulism, full discussion with patients is advised. Adequately powered, well-designed clinical trials are now needed, and multi-centre collaborations may be required to obtain the sample sizes required.

Are there distinctive sleep problems in Angelman syndrome?

Angelman syndrome is a neurogenetic condition characterized by developmental delay, absence of speech, motor impairment, epilepsy and a peculiar behavioral phenotype that includes sleep problems. It is caused by lack of expression of the UBE3A gene on the maternal chromosome 15q11-q13. Although part of the diagnostic description, 'sleep problems' are not well characterized. A pattern emerges from the available reports. It includes reduced total sleep time, increased sleep onset latency, disrupted sleep architecture with frequent nocturnal awakenings, reduced rapid eye movement (REM) sleep and periodic leg movements. Poor sleep does not significantly interfere with daytime alertness and sleep problems commonly diminish by late childhood, with continuing improvement through adolescence and adulthood. Sleep problems in Angelman syndrome reflect abnormal neurodevelopmental functioning presumably involving dysregulation of GABA-mediated inhibitory influences in thalamocortical interactions. Management may be difficult, particularly in young children; it primarily involves behavioral approaches, though pharmacological treatment may be required. The relationship between sleep and seizure disorder, and between sleep and learning raises critical questions, but more studies are needed to address these relationships adequately.

Sexsomnia: abnormal sexual behavior during sleep

This review attempts to assemble the characteristics of a distinct variant of sleepwalking called sexsomnia/sleepsex from the seemingly scarce literature into a coherent theoretical framework. Common features of sexsomnia include sexual arousal with autonomic activation (e.g. nocturnal erection, vaginal lubrication, nocturnal emission, dream orgasms). Somnambulistic sexual behavior and its clinical implications, the role of precipitating factors, diagnostic, treatment, and medico-legal issues are also reviewed. The characteristics of several individuals described in literature including their family/personal history of parasomnia as well as the abnormal behaviors occurring during sleep are reported.

A Review of Pediatric Nonrespiratory Sleep Disorders

Sleep problems are extremely common during childhood, from infancy to adolescence. Despite the prevalence of sleep problems, childhood sleep disorders are often underrecognized and undiagnosed, despite being either preventable or treatable. Sleep impacts almost all aspects of a child's functioning, and thus the increased recognition and treatment of sleep disorders will positively affect a child's well-being. Children experience the same broad range of sleep disturbances encountered in adults, including sleep apnea, insomnia, parasomnia, delayed sleep phase, narcolepsy, and restless legs, but their clinical presentation, evaluation, and management may differ. Although snoring and sleep apnea may be the most common indication for an overnight sleep study in a child, one quarter of children presenting to a sleep clinic for evaluation will have a second sleep diagnosis, which is often nonrespiratory in nature. Especially in children, ruling out sleep apnea is rarely the end point of the sleep evaluation. Clinicians involved in sleep medicine must be prepared to recognize, evaluate, and manage plans for sleep disorders across the lifespan of the patient. This article will provide an updated review of nonrespiratory pediatric sleep disorders within a developmental framework.

Sleep-related violence

Most violent behaviors arise from wakefulness. It is important to realize that violent behaviors that may have forensic science implications can arise from the sleep period. By virtue of the fact that these behaviors arise from sleep, they are executed without conscious awareness, and, therefore, without culpability. The most common underlying conditions arising from sleep are disorders of arousal (sleepwalking and sleep terrors), the rapid eye movement sleep behavior disorder, and nocturnal seizures. In addition, there are a number of psychiatric conditions (dissociative disorders, malingering, and Munchausen syndrome by proxy) that actually arise from periods of wakefulness occurring during the sleep period. The clinical and medico-legal evaluation of such cases is outlined, and should be performed by a multidisciplinary team of experienced sleep medicine practitioners.

Adult chronic sleepwalking and its treatment based on polysomnography

Adult sleepwalking affects 2.5% of the general population and may lead to serious injuries. Fifty young adults with chronic sleepwalking were studied prospectively. Clinical evaluation, questionnaires from patients and bed partners, and polysomnography were obtained on all subjects in comparison with 50 age-matched controls. Subjects were examined for the presence of psychiatric anxiety, depression and any other associated sleep disorder. Isolated sleepwalking or sleepwalking with psychiatric disorders was treated with medication. All other patients with other sleep disorders were treated only for their associated problem. Prospective follow-up lasted 12 months after establishment of the most appropriate treatment. Patients with only sleepwalking, treated with benzodiazepines, dropped out of follow-up testing and reported persistence of sleepwalking, as did patients with psychiatric-related treatment. Chronic sleepwalkers frequently presented with sleep-disordered breathing (SDB). All these patients were treated only for their SDB, using nasal continuous positive airway pressure (CPAP). All nasal CPAP-compliant patients had control of sleepwalking at all stages of follow-up. Non-compliant nasal CPAP patients had persistence of sleepwalking. They were offered surgical treatment for SDB. Those successfully treated with surgery also had complete resolution of sleepwalking. Successful treatment of SDB, which is frequently associated with chronic sleepwalking, controlled the syndrome in young adults.