Non-REM Sleep Parasomnias

OBJECTIVE

Non-rapid eye movement (non-REM) parasomnias are common across the lifespan. This article describes the manifestations, diagnosis, and management of non-REM parasomnias in adults and discusses the social implications of these conditions.

LATEST DEVELOPMENTS

Non-REM parasomnias represent a hybrid state of wakefulness and sleep, often triggered by events that increase the frequency of arousals or make it more difficult to fully arouse from sleep. Sleep deprivation, certain medications, and untreated obstructive sleep apnea are known to provoke parasomnias, particularly in those who are genetically predisposed. Non-REM parasomnias include disorders of arousal (ie, sleepwalking, sleep terrors, and confusional arousals), sleep-related eating disorder, and exploding head syndrome. Clinical overlap exists between sleep-related eating disorder and disorders of arousal, suggesting that sleep-related eating disorder may be a fourth disorder of arousal or a manifestation of sleepwalking. Exploding head syndrome is a unique parasomnia of uncertain etiology.

ESSENTIAL POINTS

Non-REM parasomnias can range from minor nuisances to severe, life-altering events. While some patients with non-REM parasomnia experience significant consequences during sleep, wakefulness, or both, non-REM parasomnias do not pose a major risk to most patients. For all patients with non-REM parasomnias, safety should be explicitly discussed and addressed. Nonpharmacologic treatment should be prioritized, as increasing total sleep time, avoiding triggering substances, and treating comorbid sleep disorders is often sufficient for the management of non-REM parasomnias. If symptoms persist despite these interventions, treatment with clonazepam or other medications can be considered.

Nonrapid Eye Movement Parasomnias

SUMMARY

Non-REM parasomnias are often observed during childhood and adolescence, by which time they typically remit. For a small percentage, these nocturnal behaviors can persist into adulthood, or in some cases, present as a new onset in adults. Non-REM parasomnias (also known as disorders of arousal) can offer a diagnostic challenge in patients who have an atypical presentation where REM sleep parasomnias, nocturnal frontal lobe epilepsy, and overlap parasomnia should be considered as part of the differential. The purpose of this review is to discuss the clinical presentation, evaluation, and management of non-REM parasomnias. The neurophysiology behind non-REM parasomnias is considered, and this gives insights into their cause and the potential for treatment.

A case-control study of sexualised behaviour in sleep: A strong association with psychiatric comorbidity and relationship difficulties

Sexualised behaviour in sleep (SBS) is a relatively rare parasomnia consisting of instinctive behaviours of a sexual nature occurring during non-rapid-eye movement (NREM) sleep. Little information exists at present regarding the clinical features and onset of this condition as well as its link to psychiatric comorbidity, other sleep disorders and history of adverse early life experience. Aims were to typify the condition further and compare features of SBS patients to those with other NREM parasomnias.

METHODS

Details of 335 consecutive patients presenting to a single tertiary sleep centre with non-rapid eye movement (NREM)-parasomnias over a 15-year period (2005-2020) were examined. Data were collated by reviewing case-notes for anthropometric data, past medical history, clinical findings, and video polysomnography. SBS patients were compared to a cohort of 270 non-SBS, NREM-sleep disorder patients (case-control) to ascertain whether they had any distinguishing features from other parasomnias classified in this group.

RESULTS

Sixty-five patients with SBS were identified: 58 males, 7 females (comprising 19.4% of the cohort overall). Mean age at presentation was 33(±9.5) years. Onset of behaviours was commoner in adulthood in the SBS cohort, whereas non-SBS, NREM-parasomnia onset (n = 270) was commoner in childhood: 61.1% and 52.9% respectively (p = 0.007). An association was identified between the presence of psychiatric diagnoses and onset of SBS (p = 0.028). Significant triggers for SBS behaviours included alcohol consumption (p < 0.001), intimate relationship difficulties (p = 0.009) and sleep deprivation (p = 0.028). Patients with SBS were significantly more likely to report sleepwalking as an additional NREM behaviour (p < 0.001). Males were more likely to present at clinic together with their bedpartner and females presented alone. A history of SBS appeared to be more common in those working in the armed forces or the police compared to those presenting with non-SBS, NREM-parasomnias (p = 0.004).

CONCLUSIONS

SBS is more common in clinical practice than previously described and presents with some distinguishing features within the NREM disorder category. This study is the first to identify that onset in childhood or lack of amnesia does not preclude the condition and that patterns of presentation differ between men and women. Sleepwalkers particularly should be asked about SBS. Comorbid psychiatric conditions, profession and intimate partner difficulties are strong determinants of the presentation.

The prevalence of sleep loss and sleep disorders in young and old adults

The ability to sleep declines with age. The National Sleep Foundation, USA has recommended a minimum sleep amount for all ages. Individuals who experience sleep lesser than the recommended amount could be sleep-deprived. Several factors like stress, altered circadian cycle, medical conditions, etc. cause sleep deficiency. Almost 50-60 % of elderly population suffer from sleep disorders such as sleep apnea, restless legs syndrome, REM sleep behavior disorder, etc. Chronic sleep deprivation may further lead to the development of diseases such as Alzheimer's and Parkinson's. This paper reviews the prevalence of sleep disorders and consequences of sleep loss in young and old adults.

Adaptive Solutions to the Problem of Vulnerability During Sleep

Sleep is a behavioral state whose quantity and quality represent a trade-off between the costs and benefits this state provides versus the costs and benefits of wakefulness. Like many species, we humans are particularly vulnerable during sleep because of our reduced ability to monitor the external environment for nighttime predators and other environmental dangers. A number of variations in sleep characteristics may have evolved over the course of human history to reduce this vulnerability, at both the individual and group level. The goals of this interdisciplinary review paper are (1) to explore a number of biological/instinctual features of sleep that may have adaptive utility in terms of enhancing the detection of external threats, and (2) to consider relatively recent cultural developments that improve vigilance and reduce vulnerability during sleep and the nighttime. This paper will also discuss possible benefits of the proposed adaptations beyond vigilance, as well as the potential costs associated with each of these proposed adaptations. Finally, testable hypotheses will be presented to evaluate the validity of these proposed adaptations.

Sleepwalking, sleep terrors, sexsomnia and other disorders of arousal: the old and the new

Disorders of arousal (DOA) is an umbrella term initially covering classical sleepwalking, sleep terrors, and confusional arousals, and now including a wider spectrum of specialised forms of non rapid eye movement (non REM) parasomnias such as sexsomnia, sleep-related eating disorder, and sleep-related choking syndrome. Growing evidence has shown that DOA are not restricted to children but are also prevalent in adults (2%-4% of the adult population). While DOA run in family, genetics studies remain scarce and inconclusive. In addition to the risk of injury on themselves and others (including sexual assaults in sexsomnia), adults with DOA frequently suffer from excessive daytime sleepiness, pain, and altered quality of life. The widespread view of DOA as automatic and amnesiac behaviours has now been challenged by subjective (dream reports) and objective (dream-enacting behaviours documented on video-polysomnography) observations, suggesting that sleepwalkers are 'dream walking' during their episodes. Behavioural, experiential, cognitive, and brain (scalp electroencephalography [EEG], stereo-EEG, high density-EEG, functional brain imaging) data converge in showing a dissociated pattern during the episodes. This dissociated pattern resembles the new concept of local arousal with a wake-like activation in motor and limbic regions and a preserved (or even increased) sleep intensity over a frontoparietal network. EEG and behavioural criteria supporting the DOA diagnosis with high sensitivity and specificity are now available. However, treatment is still based on controlling priming and precipitating factors, as well as on clinicians' personal experience with sedative drugs. Placebo-controlled trials are needed to improve patients' treatment. DOA deserve more attention from sleep researchers and clinicians.

Validation of the Dutch translation of the Paris Arousal Disorders Severity Scale for NREM parasomnias in a one-year and one-month version

STUDY OBJECTIVES

We created a Dutch version of the Paris Arousal Disorders Severity Scale, which assesses non-rapid eye movement (NREM) parasomnia symptoms over the past year (PADSS-year). This questionnaire was previously validated in patients with sleep walking and/or sleep terrors ('SW/ST'). We validated the questionnaire in SW/ST patients, and in a broader population, including patients with confusional arousals, co-morbidities, and medication-users ('other NREM parasomnias'). Furthermore, we introduced a version covering the past month (PADSS-month), with the potential purpose of evaluating symptom evolution and treatment response.

METHODS

We compared PADSS scores among 54 SW/ST patients, 34 age-matched controls, and 23 patients with other NREM parasomnias. We evaluated discriminative capacity, internal consistency and construct validity. Furthermore, we assessed the test-retest reliability and treatment response of PADSS-month.

RESULTS

Healthy controls scored significantly lower than both patient groups. We found an excellent diagnostic accuracy (AUC PADSS-year 0.990, PADSS-month 0.987) and an acceptable internal consistency. Exploratory factor analysis identified three components: 'behaviors outside the bed', 'behaviors in/around the bed', and 'violent behaviors', the former two factors reflecting the distinction between SW and ST. PADSS-month showed an acceptable test-retest reliability (0.75). Additionally, PADSS-month significantly decreased after pharmaceutical and/or behavioral treatment. This change was correlated with the clinical impression of the caregiver, implying that PADSS-month is sensitive to treatment effects.

CONCLUSIONS

The Dutch PADSS questionnaire can be used as a screening tool in a broad population of NREM parasomnia patients, not only SW/ST. Furthermore, we validated a PADSS-month version, to assess the evolution of symptoms and treatment effect.

From burlesque to horror: a century of sleepwalking on the silver screen

BACKGROUND

Long before being described as a disorder, sleepwalking was considered as a mysterious phenomenon inspiring artwork. From the early beginning of cinema, sleepwalkers were shown to populations, playing a crucial role in storytelling and collective knowledge.

OBJECTIVE

We characterized how sleepwalking has been portrayed in a large number of movies from the origins of cinema to recent years.

METHODS

Movies containing the words "sleepwalking" or "somnambulism" were searched for in International Movie Databases. Types of movies, sleepwalking characters, postures and behaviors during episodes, triggers, and suggested treatments were collected.

RESULTS

Production of 87 movies and 22 cartoons portraying sleepwalkers was clustered around two peaks, in the 1910s and 2010s. Comedies predominated before 1960, and thriller/horror movies as a dominant genre after 1960. In contrast with real-life sleepwalking epidemiology, sleepwalkers are more often portrayed as women than men (and often wearing a transparent white nightgown), as adults more than children on-screen, and 23% suffered psychiatric comorbidities. The unrealistic posture of outstretched arms and eyes closed was found in 20% of movies and 79% of cartoons. Night terrors, sexsomnias (kissing, having sex, initiated pregnancy), sleep-related eating and sleep driving were also featured. Homicides and falls while sleepwalking were recurrent fear-inducing topics. The first sleep EEG was featured in a sleepwalking movie in 1985, and a sleep specialist gave his first advice in 1997.

DISCUSSION

The representation of sleepwalking on the screen seems to have evolved from popular, unrealistic stereotypes of somnambulism towards a medical condition, paralleling the development of sleep medicine.

Resolution of sexsomnia with paroxetine

None

Sexsomnia is a parasomnia consisting of sexual behavior during non-rapid eye movement sleep. To date, there have been 116 clinical cases of sexsomnia reported and most were treated with clonazepam. We present a case of an adult male with sexsomnia that started during his college days. He presented to us because of problems in his current marriage arising from sexual behavior during sleep. Polysomnography revealed no significant sleep-disordered breathing, electroencephalography abnormality, or abnormal movement during non-rapid eye movement and rapid eye movement (REM) sleep. Alcohol consumption was reported to worsen his sexsomnia. To avoid the neuro-depressant effects of benzodiazepines, paroxetine was administered and resulted in complete resolution of sexsomnia.

REM sleep behavior disorder: Mimics and variants

Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia with dream-enactment behaviors occurring during REM sleep and associated with the lack of the physiological REM sleep muscle atonia. It can be isolated and secondary to other neurological or medical conditions. Isolated RBD heralds in most cases a neurodegenerative condition due to an underlying synucleinopathy and consequently its recognition is crucial for prognostic implications. REM sleep without atonia on polysomnography is a mandatory diagnostic criterion. Different conditions may mimic RBD, the most frequent being obstructive sleep apnea during sleep, non-REM parasomnia, and sleep-related hypermotor epilepsy. These diseases might also be comorbid with RBD, challenging the evaluation of disease severity, the treatment choices and the response to treatment evaluation. Video-PSG is the gold standard for a correct diagnosis and will distinguish between different or comorbid sleep disorders. Careful history taking together with actigraphy may give important clues for the differential diagnosis. The extreme boundaries of RBD might also be seen in more severe and complex conditions like status dissociatus or in the sleep disorders' scenario of anti IgLON5 disease, but in the latter both clinical and neurophysiological features will differ. A step-by-step approach is suggested to guide the differential diagnosis.

Sleep-Related Hypermotor Epilepsy vs Disorders of Arousal in Adults: A Step-Wise Approach to Diagnosis

Disorders of arousal (DoA) and sleep-related hypermotor epilepsy (SHE) are sleep-related events characterized by complex, often bizarre, and violent behaviors. DoA are involuntary motor manifestations of various complexities occurring during incomplete awakening from non-rapid eye movement sleep. SHE is a focal epilepsy characterized by stereotyped hyperkinetic or/and asymmetric tonic/dystonic seizures usually arising from non-rapid eye movement sleep. Even if many aspects regarding DoA and SHE have been clarified, the differential diagnosis remains challenging, because DoA and SHE share some semiologic features and genetic background. The clinical history, collected from the patient and his/her witness, represents the first and common milestone in the diagnosis. Validated questionnaires constitute suitable screening tools that could guide further analysis. The worldwide availability of homemade video recordings has increased the possibility of adding more objective information to the clinical history alone. The confirmed diagnosis relies on video-polysomnographic recording although it requires time, economic resources, and specific skills for the analysis. In this review we propose a simple diagnostic algorithm for the differential diagnosis between DoA and SHE in adults, based on the most updated knowledge, from the simpler tool to the most specific and tailored one.

NonREM Disorders of Arousal and Related Parasomnias: an Updated Review

Parasomnias are abnormal behaviors and/or experiences emanating from or associated with sleep typically manifesting as motor movements of varying semiology. We discuss mainly nonrapid eye movement sleep and related parasomnias in this article. Sleepwalking (SW), sleep terrors (ST), confusional arousals, and related disorders result from an incomplete dissociation of wakefulness from nonrapid eye movement (NREM) sleep. Conditions that provoke repeated cortical arousals, and/or promote sleep inertia, lead to NREM parasomnias by impairing normal arousal mechanisms. Changes in the cyclic alternating pattern, a biomarker of arousal instability in NREM sleep, are noted in sleepwalking disorders. Sleep-related eating disorder (SRED) is characterized by a disruption of the nocturnal fast with episodes of feeding after arousal from sleep. SRED is often associated with the use of sedative-hypnotic medications, in particular the widely prescribed benzodiazepine receptor agonists. Compelling evidence suggests that nocturnal eating may in some cases be another nonmotor manifestation of Restless Legs Syndrome (RLS). Initial management should focus upon decreasing the potential for sleep-related injury followed by treating comorbid sleep disorders and eliminating incriminating drugs. Sexsomnia is a subtype of disorders of arousal, where sexual behavior emerges from partial arousal from nonREM sleep. Overlap parasomnia disorders consist of abnormal sleep-related behavior both in nonREM and REM sleep. Status dissociatus is referred to as a breakdown of the sleep architecture where an admixture of various sleep state markers is seen without any specific demarcation. Benzodiazepine therapy can be effective in controlling SW, ST, and sexsomnia, but not SRED. Paroxetine has been reported to provide benefit in some cases of ST. Topiramate, pramipexole, and sertraline can be effective in SRED. Pharmacotherapy for other parasomnias continues to be less certain, necessitating further investigation. NREM parasomnias may resolve spontaneously but require a review of priming and predisposing factors.

Sexual Behaviors and Sexual Health of Sexsomnia Individuals Aged 18-58

Objective: The objective of this study was to address the relationships between demographics and sexsomnia episodes, and sexual health issues in affected individuals. This study is the first sexsomnia survey conducted in Turkey. Sexsomnia comprises involuntary, unconscious sexual behavior during sleep, observed by a bed partner. Method:To reach people with and without sexsomnia, an online survey method was used. Among 274 participants, 42 of them reported having sexsomnia. Results: Women who do not have sexsomnia have more sexual problems than women who have sexsomnia episodes. The sexsomnia experiences of men and women also differed. Additionally, there were gender differences with difficulties caused by the sexsomnia. Conclusions: There is a need for further studies on sexsomnia that address socio-cultural, gender, and biological factors (including sleep disorders).

Sleep and Sex: A Review of the Interrelationship of Sleep and Sexuality Disorders in the Female Population, Through the Lens of Sleeping Beauty Syndrome

INTRODUCTION

For many, sleep and sex are crucial for physical, emotional, and mental well-being. Poor sleep quality is linked to a myriad of ailments from coronary artery disease to major depressive disorder. Likewise, a decrease in the frequency of sexual activity is associated with a decrease in self-rated health status. Kleine-Levin syndrome (KLS) is a rare sleep disorder that provides a unique lens to examine the intricate interplay between sleep and sex as it is one of the few sleep disorders defined by concomitant sexual dysfunction.

OBJECTIVES

This study reviews the literature on links between sleep disorders and sexuality with a focus on women's health followed by a case study of unusual patient with KLS with persistent genital arousal disorder.

METHODS

Literature searches were conducted for English language publications, including foreign language publications with English abstracts with ninety-five articles reviewed. The literature review is followed by a case report.

RESULTS

We review the known literature linking sleep and women's sexual health with a focus on insomnia, circadian rhythm sleep disorder, obstructive sleep apnea, restless leg syndrome, sexsomnia, and KLS. We then present a case of KLS-associated persistent genital arousal disorder, which was amenable to treatment with a multimodal approach aimed at symptomatic relief with intravaginal diazepam suppositories, topical clitoral lidocaine, and duloxetine.

CONCLUSION

This case highlights that hypersexuality and persistent arousal cannot effectively be treated in isolation but rather must be contextualized within a patient's broader medical history and diagnoses. Specifically, sleep quality and potential sleep disorders should be assessed for those presenting with sexual health complaints (and vice versa). Zwerling B, Keymeulen S, Krychman ML. Sleep and Sex: A Review of the Interrelationship of Sleep and Sexuality Disorders in the Female Population, Through the Lens of Sleeping Beauty Syndrome. Sex Med Rev 2021;9:221-229.

NREM sleep parasomnias as disorders of sleep-state dissociation

Non-rapid eye movement (NREM) sleep parasomnias (or NREM parasomnias) are fascinating disorders with mysterious neurobiological substrates. These conditions are common and often severe, with social, personal and forensic implications. The NREM parasomnias include sleepwalking, sleep terrors and confusional arousals - collectively termed disorders of arousal (DOAs) - as well as less well-known entities such as sleep-related sexual behaviours and eating disorders. Affected patients can exhibit waking behaviours arising abruptly out of NREM sleep. Although the individual remains largely unresponsive to the external environment, their EEG shows both typical sleep-like and wake-like features, and they occasionally report dreaming afterwards. Therefore, these disorders offer a unique natural model to explore the abnormal coexistence of local sleep and wake brain activity and the dissociation between behaviour and various aspects of consciousness. In this article, we critically review major findings and updates on DOAs, focusing on neurophysiological studies, and offer an overview of new clinical frontiers and promising future research areas. We advocate a joint effort to inform clinicians and the general public about the management and follow-up of these conditions. We also strongly encourage collaborative multicentre studies to add more objective polysomnographic criteria to the current official diagnostic definitions and to develop clinical practice guidelines, multidisciplinary research approaches and evidence-based medical care.

Sexsomnia in an Adolescent

ABSTRACT

Sexsomnia has been reported and is well described in 115 prior cases in the literature. There have been associations with other sleep disorders serving as triggers for confusional arousals, thereby worsening sexsomnia episodes. We present a case of an adolescent boy with a history of resected and treated pineoblastoma who later developed sexsomnia marked by multiple episodes of masturbatory events per night. He had additional suspicions of obstructive sleep apnea. Polysomnography confirmed severe obstructive sleep apnea and captured multiple episodes of sexsomnia from both REM and NREM sleep. The patient also had daytime symptoms of severe anxiety and hypersomnia that required pharmacological intervention, cognitive behavioral techniques, and hypnosis. The patient showed improvement with hypnosis along with a multimodal approach to the treatment of sexsomnia.

Sleep-Related Orgasms in a 57-Year-Old Woman: A Case Report

ABSTRACT

We report a case of problematic spontaneous orgasms during sleep in a 57-year-old woman who also complained of hypnic jerks and symptoms of exploding head syndrome. To our knowledge, this is the first case report in the English language literature of problematic spontaneous orgasms during sleep. She had a complex medical and psychiatric history, and was taking oxycontin, venlafaxine, amitriptyline, and lurasidone. Prolonged video electroencephalogram monitoring did not record any ictal or interictal electroencephalogram discharges, and nocturnal video polysomnography monitoring did not record any behavioral or orgasmic event. Periodic limb movement index was zero events/h. Severe central sleep apnea was detected with apnea-hypopnea index = 130 events/h, but she could not tolerate positive airway pressure titration. Sleep architecture was disturbed, with 96.4% of sleep spent in stage N2 sleep. Bedtime clonazepam therapy (1.5 mg) was effective in suppressing the sleep-related orgasms and hypnic jerks.