Prevalence of different parasomnias in the general population

Comparing patients treated with CBT for insomnia with healthy sleepers and sleepers with past insomnia on dimensions of sleep health

OBJECTIVES

To compare patients treated with cognitive behavioral therapy for insomnia (CBT-I) with healthy sleepers and individuals with past but not current insomnia on multidimensional sleep health.

METHODS

The study evaluates CBT-I on six dimensions of sleep health (regularity, satisfaction, alertness, timing, efficiency, duration) in a sample of individuals with insomnia compared to two other unique sleep samples. Participants were in one of three groups: insomnia (CUR, n = 299), healthy sleeper (HS, n = 122), or past insomnia (PAST, n = 35). Daily diaries and validated measures were employed to capture six dimensions of sleep health. The CUR group received four 60-minute sessions of CBT-I every 2weeks, and sleep health indices were measured at baseline and post-treatment. The HS and PAST groups were measured only at baseline.

RESULTS

Results of the pairwise t tests indicated improvements in sleep satisfaction, alertness (fatigue but not sleepiness), timing, efficiency, and duration (Cohen's d=0.22 to 1.55). ANCOVA models revealed significant differences in sleep health scores between treated insomnia patients and the other two sleep groups. Treated patients demonstrated less bedtime and risetime variability, in addition to lower napping duration. Overall, the study observed significant changes in various domains of sleep health after four sessions of cognitive behavioral therapy for insomnia; however, differences remain when compared to the other groups in the study.

CONCLUSION

There may be ongoing sleep vulnerability in patients treated with cognitive behavioral therapy for insomnia though future inclusion of a control group would increase internal validity. Borrowing from transdiagnostic sleep modules may be helpful to support remaining deficits after cognitive behavioral therapy for insomnia.

From trenches to technology: a narrative review of sleep medicine in the military

Diagnoses of military-relevant sleep disorders have increased substantially since the terrorist attacks of September 11, 2001. The cause of this increase appears to be complicated and multifactorial, with military and civilian populations clearly differing with respect to both the nature and distribution of sleep disorders diagnoses. In part, these differences may be attributable to the fact that a majority of service members are chronically sleep-restricted-an unavoidable consequence of continuous and sustained military operations that "set the stage" for development of specific sleep disorders. The purpose of this narrative review is to describe the military relevance of several common sleep disorders, assess the extent to which these disorders currently constitute a burden on the military health care system, and suggest strategies to alleviate that burden. The military health care system does not have enough sleep medicine providers to address the immediate and long-term consequences of sleep disorders in military personnel. Digital technologies and education packages can be leveraged to improve access to care.

CITATION

Thomas CL, Carr K, Yang F, et al. From trenches to technology: a narrative review of sleep medicine in the military. J Clin Sleep Med. 2024;20(6):973-981.

Lamentations in the night: A systematic review on catathrenia

Catathrenia is a loud expiratory moan during sleep that is a social embarrassment and is sometimes confused with central apnea on polysomnography. It affects about 4% of adults, but cases are rarely referred to sleep centers. Catathrenia affects males and females, children and adults, who are usually young and thin. A "typical" catathrenia begins with a deep inhalation, followed by a long, noisy exhalation, then a short, more pronounced exhalation, followed by another deep inhalation, often accompanied by arousal. The many harmonics of the sound indicate that it is produced by the vocal cords. It is often repeated in clusters, especially during REM sleep and at the end of the night. It does not disturb the sleepers, but their neighbors, and is associated with excessive daytime sleepiness in one-third of cases. The pathophysiology and treatment of typical catathrenia are still unknown. Later, a more atypical catathrenia was described, consisting of episodes of short (2 s), regular, semi-continuous expiratory moans during NREM sleep (mainly in stages N1 and N2) and REM sleep, often in people with mild upper airway obstruction. This atypical catathrenia is more commonly reduced by positive airway pressure and mandibular advancement devices that promote vertical opening.

ZleepAnlystNet: a novel deep learning model for automatic sleep stage scoring based on single-channel raw EEG data using separating training

Numerous models for sleep stage scoring utilizing single-channel raw EEG signal have typically employed CNN and BiLSTM architectures. While these models, incorporating temporal information for sequence classification, demonstrate superior overall performance, they often exhibit low per-class performance for N1-stage, necessitating an adjustment of loss function. However, the efficacy of such adjustment is constrained by the training process. In this study, a pioneering training approach called separating training is introduced, alongside a novel model, to enhance performance. The developed model comprises 15 CNN models with varying loss function weights for feature extraction and 1 BiLSTM for sequence classification. Due to its architecture, this model cannot be trained using an end-to-end approach, necessitating separate training for each component using the Sleep-EDF dataset. Achieving an overall accuracy of 87.02%, MF1 of 82.09%, Kappa of 0.8221, and per-class F1-socres (W 90.34%, N1 54.23%, N2 89.53%, N3 88.96%, and REM 87.40%), our model demonstrates promising performance. Comparison with sleep technicians reveals a Kappa of 0.7015, indicating alignment with reference sleep stags. Additionally, cross-dataset validation and adaptation through training with the SHHS dataset yield an overall accuracy of 84.40%, MF1 of 74.96% and Kappa of 0.7785 when tested with the Sleep-EDF-13 dataset. These findings underscore the generalization potential in model architecture design facilitated by our novel training approach.

Association of nightmares with cardio-cerebrovascular disease, hypertension and hyperlipidemia in older adults: A population-based cross-sectional study

OBJECTIVE

This cross-sectional study investigated the relationship of nightmares with cardio-cerebrovascular disease (CVD), hypertension and hyperlipidemia which are major preceding diseases of CVD in older adults.

METHODS

Participants (n = 2824; mean age 63.6 ± 6.6 years, females 49.3%) completed the Disturbing Dream and Nightmare Severity Index (DDNSI), which was used to divide the sample into either the Nightmare or Non-Nightmare group (cut-off score ≥ 10). Demographic information, history of CVD (cerebrovascular disease, myocardial infarction, congestive heart failure, coronary artery disease, and arrhythmia), hypertension, hyperlipidemia, and self-report questionnaires about stress (Perceived Stress Scale), depression (Beck Depression Inventory), sleep quality (Pittsburgh Sleep Quality Index), and insomnia symptoms were also collected.

RESULTS

Among the sample, 379 participants (13.4%) reported experiencing nightmares more than once a year, and 73 participants (2.6%) were classified as having nightmare disorder based on DDNSI scores (≥10). 11.3% of participants (n = 319) reported having more than one CVD. Approximately half of the participants reported a history of hypertension (52.1%, n = 1471) and hyperlipidemia (47.7%, n = 1346). Logistic regression analysis indicated the Nightmare group was 2.04 times at higher risk for hyperlipidemia (OR = 2.04, 95% CI 1.22-3.40, p = .006) after controlling for covariates compared to the Non-Nightmare group. Although non-significant, there was a trend toward a higher risk of hypertension in the Nightmare group (OR = 1.67, 95% CI 0.99-2.84, p = .056).

CONCLUSIONS

Results of this study indicate frequent nightmares in older adults may be associated with hyperlipidemia, which are risk factors for CVD. Further studies are needed to explore nightmares' directionality and health consequences in an aging population.

Understanding Sexual Parasomnias: A Review of the Current Literature on Their Nature, Diagnosis, Impacts, and Management

Sexual behavior during sleep, known as sexual parasomnias, has captured the interest of researchers and clinicians. These parasomnias involve various sexual activities that occur unconsciously during sleep. Although relatively rare, they can profoundly affect well-being and relationships and can carry legal consequences. Understanding their nature, prevalence, and causes is crucial for advancing knowledge in this field. This article revisits the topic of sexsomnia, presenting new data and discussing cases published from 2007 to 2023. By analyzing these cases, we aim to enhance recognition, diagnosis, and management of sexsomnia, reducing stigma and providing better support for affected individuals.

Forensic Implications of the Parasomnias

Although many sleep-related behaviors are benign, others can result in physical or sexual aggression toward bed partners or others. Individuals who engage in sleep-related violence (SRV) and sexual behavior in sleep (SBS) may face legal sanctions for their behavior. Attorneys or legal decision-makers may call on an expert to evaluate a defendant and opine about the veracity of an alleged parasomnia diagnosis, the criminal responsibility of the defendant, and his risk of violence to others. This article reviews the phenomena of SRV and SBS and guides evaluators in the forensic considerations relevant to parasomnias.

Impact of REM Sleep Behavior and Sleep Talking on Mortality in Parkinson's Disease

Background REM sleep behavior disorder (RBD) is a prodromal marker for Parkinson's disease (PD) and other alpha-synucleinopathies. Sleep talking (ST) is an isolated symptom and is frequent in PD and RBD. Here, we investigate the associations of ST and RBD with the mortality of PD patients. Patients and methods A total of 1,500 PD patients were randomly selected from the registry of the Finnish Parkinson's Association. Of the 855 that participated at baseline, 645 gave permission for follow-up studies. We gathered a completely filled sleep questionnaire and mortality information from 384 subjects. The Nelson-Aalen test and Cox hazard ratios (HR) were used for mortality analyses. Results The mean follow-up time was 4.3 years (0.3-7.0). PD patients with RBD or frequent ST had more non-motor symptoms. Depression, hallucinations, constipation, and excessive daytime sleepiness were more prevalent among subjects with RBD. Subjects with RBD and frequent ST (talking in their sleep ≥ once per week) had increased mortality (HR: 1.90, 95% CI: 1.18-3.06). RBD without frequent ST was not associated with mortality (HR: 0.77, 95% CI: 0.4-1.5). Frequent ST was associated with increased mortality when adjusted for age, PD duration, depression, gender, RBD, BMI, and hallucinations (HR: 2.22, 95% CI: 1.10-4.51). Additionally, age, duration of PD, arterial hypertension, and lower BMI were associated with increased mortality. Male gender, dopaminergic medication, depression, and hallucinations were not significantly associated with mortality. Conclusions RBD with frequent ST and ST alone appear to be risk factors for mortality in PD. Frequent ST may be a sign representing wider neurodegeneration. RBD subjects and frequent sleep talkers demonstrated more non-motor symptoms compared to PD without RBD or ST. Our findings have clinical implications. It remains to be seen if frequent ST indicates a poorer prognosis. Prospective studies are needed to find whether frequent ST is also a risk factor for developing PD.

Common Childhood Sleep Problems and Disorders

BACKGROUND

Sleep insufficiency and disturbances affect the physical, cognitive, and emotional well-being of children.

OBJECTIVE

To perform a narrative review on common sleep problems and disorders encountered in primary care for children and adolescents.

METHODS

A search of English literature in the Pubmed and Google Scholar databases published from 1 January 2000 till 31 October 2021 was conducted with the keywords "sleep problem" or "sleep disorder" and "child" or "adolescent". Findings in the relevant articles and cross-references were compiled.

RESULTS

Sleep duration and habits of children vary widely across countries with different cultural backgrounds. There is robust evidence to support the promotion of positive bedtime routines and sleep hygiene as prevention and management of sleep problems. 15-70% of parents reported their children having sleep problems or disturbances. Common sleep complaints include difficulty in initiation or maintenance of sleep, abnormal behaviors or movements, snoring or abnormal breathing, and excessive daytime sleepiness. Comprehensive sleep history and a sleep diary are the first steps for evaluation. Home video and actigraphy may be used as preliminary tools to confirm the history. Referrals to a sleep specialist for polysomnography and other tests are needed, if suspecting specific sleep disorders, such as obstructive sleep apnea and narcolepsy, needs timely intervention. Common sleep disorders in different age groups encountered in primary care are reviewed with clinical features, indications for evaluation, and treatment options summarized.

CONCLUSION

Screening for sleep problems shall be an integral part of each child's health care visit. It is important to evaluate the impact of common sleep problems and identify specific sleep disorders for early intervention to prevent long-term adverse outcomes.

Gender differences in spontaneous adverse event reports associated with zolpidem in South Korea, 2015-2019

Study objectives: While zolpidem is considered as an example of a gender effect on drug response, there is insufficient evidence to reach a consensus. This study aimed to investigate gender differences in adverse events (AEs) of zolpidem. Methods: We estimated the difference between the reporting odds ratios (RORs) calculated in gender subgroups for the AEs signals detected in data mining using 2015-2019 Korea voluntary adverse drug events reporting system (KAERS) data. Different reporting risk by gender was evaluated by using the log RORs being significantly different by gender at the 5% significance level and the 95% confidence intervals of the gender ROR. Results: A total of 94 AE signals were detected. Among these, 35 signals showed significant disparities by gender at the 5% level or were detected only in one gender. When categorized by similarity of AEs, parasomnia including somnambulism and paroniria, and cardiovascular disorders including coronary thrombosis had higher reporting risks in women. Men were more likely to report cognitive disorders such as delirium, insomnia related disorders, and movement disorders. Among all AEs with gender differences in reporting risk, the difference in somnambulism was the most consistent and substantial. Conclusion: For several AEs associated with zolpidem, gender-based reporting disparities were evident. Notably, women exhibited a higher susbeptibility to somnambulism, potentially serious adverse effects of zolpidem. This underscores the need for further investigation into the underlying factors influencing these gender-specific reporting patterns.

Behavioral and psychological treatments for NREM parasomnias: A systematic review

BACKGROUND

Non-rapid eye movement (NREM) parasomnias are often benign and transient, requiring no formal treatment. However, parasomnias can also be chronic, disrupt sleep quality, and pose a significant risk of harm to the patient or others. Numerous behavioral strategies have been described for the management of NREM parasomnias, but there have been no published comprehensive reviews. This systematic review was conducted to summarize the range of behavioral and psychological interventions and their efficacy.

METHODS

We conducted a systematic search of the literature to identify all reports of behavioral and psychological treatments for NREM parasomnias (confusional arousals, sexsomnia, sleepwalking, sleep terrors, sleep-related eating disorder, parasomnia overlap disorder). This review was conducted in line with PRISMA guidelines. The protocol was registered with PROSPERO (CRD42021230360). The search was conducted in the following databases (initially on March 10, 2021 and updated February 24, 2023): Ovid (MEDLINE), Cochrane Library databases (Wiley), CINAHL (EBSCO), PsycINFO (EBSCO), and Web of Science (Clarivate). Given a lack of standardized quantitative outcome measures, a narrative synthesis approach was used. Risk of bias assessment used tools from Joanna Briggs Institute.

RESULTS

A total of 72 publications in four languages were included, most of which were case reports (68%) or case series (21%). Children were included in 32 publications and adults in 44. The most common treatment was hypnosis (33 publications) followed by various types of psychotherapy (31), sleep hygiene (19), education/reassurance (15), relaxation (10), scheduled awakenings (9), sleep extension/scheduled naps (9), and mindfulness (5). Study designs and inconsistent outcome measures limited the evidence for specific treatments, but some evidence supports multicomponent CBT, sleep hygiene, scheduled awakenings, and hypnosis.

CONCLUSIONS

This review highlights the wide breadth of behavioral and psychological interventions for managing NREM parasomnias. Evidence for the efficacy of these treatments is limited by the retrospective and uncontrolled nature of most research as well as the infrequent use of validated quantitative outcome measures. Behavioral and psychological treatments have been studied alone and in various combinations, and recent publications suggest a trend toward preference for multicomponent cognitive behavioral therapies designed to specifically target priming and precipitating factors of NREM parasomnias.

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.

A Rare Case of Sleep Terror Disorder in an Adult With Chronic Alcohol Abuse: A Case Report and Literature Review

Sleep terror disorder and chronic alcohol abuse are severe conditions that can significantly impact an individual's quality of life. Sleep terror disorder is characterized by sudden and intense episodes of fear or terror, while chronic alcohol abuse can lead to physical and psychological problems that can negatively impact sleep quality. This patient had terminal insomnia with episodes of terror, screaming, and no memory of arousal. Treatment of sleep terror disorder in chronic alcohol abuse patients involves addressing any underlying medical or psychological issues, medication, and cognitive-behavioral therapy (CBT). CBT can help identify and dispute harmful thought patterns and teach coping mechanisms. We present a case of an adult male who had terminal insomnia with episodes of terror, screaming, and no memory of arousal.

The Correlation of Sleep Disturbance and Location of Glioma Tumors: A Narrative Review

Sleep disturbance can occur when sleep centers of the brain, regions that are responsible for coordinating and generating healthy amounts of sleep, are disrupted by glioma growth or surgical resection. Several disorders cause disruptions to the average duration, quality, or patterns of sleep, resulting in sleep disturbance. It is unknown whether specific sleep disorders can be reliably correlated with glioma growth, but there are sufficient numbers of case reports to suggest that a connection is possible. In this manuscript, these case reports and retrospective chart reviews are considered in the context of the current primary literature on sleep disturbance and glioma diagnosis to identify a new and useful connection which warrants further systematic and scientific examination in preclinical animal models. Confirmation of the relationship between disruption of the sleep centers in the brain and glioma location could have significant implications for diagnostics, treatment, monitoring of metastasis/recurrence, and end-of-life considerations.

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.

Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias

STUDY OBJECTIVES

This pilot study determined whether transdiagnostic cognitive behavioral therapy for parasomnias (CBTp) reduces parasomnia and activity levels during sleep in a sample of adult sleep clinic outpatients. A secondary objective was to assess whether treatment produces improvements in daytime fatigue/sleepiness, perceived cognition, mood, and depression/anxiety/stress, as well as functional impairment in work and leisure activities.

METHODS

This was a randomized controlled trial with CBTp and self-monitoring control conditions. Participants were 19 adults with a DSM 5 parasomnia disorder who received individual CBTp virtually from their homes. CBTp consisted of psychoeducation, sleep hygiene and safety instructions, relaxation training, parasomnia techniques, and relapse prevention in a 6-week manualized, structured program.

RESULTS

Using a repeated measures analysis of variance model, and relative to a self-monitoring control condition, results showed that CBTp produced statistically significant improvements in parasomnia frequency, severity, nocturnal activity, and sleep efficiency. There was a trend toward reduced sleep-onset latency and improved work and social adjustment. Of treated participants, 100% rated themselves as improved at study conclusion.

CONCLUSIONS

Implications of these findings are that cognitive behavioral interventions for parasomnias are effective in lessening parasomnias. More investigation into this type of treatment is warranted.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Impact of Cognitive Behavioral Therapy on Parasomnias; URL: https://clinicaltrials.gov/ct2/show/NCT04633668; Identifier: NCT04633668.

CITATION

Vincent N, Dirkse D, Giannouli E, McQuarrie A. Transdiagnostic cognitive behavioral therapy for nightmares and parasomnias. J Clin Sleep Med. 2023;19(3):499-509.

Sleep quality of medical students and relationships with academic performances

OBJECTIVE

Sleep health is a major public health concern because of its correlation with physical and mental health, and it may be particularly altered in medical students. This study aims: i) to examine the sleep characteristics of French medical students and their knowledge about basic sleep hygiene rules and; ii) to examine the correlations between sleep quality and academic performances, as well as between sleep quality and sleep knowledge.

METHODS

Students from 4th, 5th and 6th years of medicine, of the Faculty of Paris Diderot, voluntarily responded to an online questionnaire including PSQI and multiple-choice quizzes (MCQ) about basic sleep hygiene rules.

RESULTS

From the 177 participants, 49.7% had a poor sleep (PSQI>5). Regarding sleep latency, 44.6% needed>30min to fall asleep at least once a week, 26.5% slept 6 hours or less by night, 42.4% of them qualified their sleep quality as bad or very bad. A serious lack of knowledge about basic sleep hygiene rules was observed, with an average score at the MCQ of 6.61/10, and only 31% of medical students were aware of basic good sleep habits. Significant correlations were observed between sleep efficiency and all academic mean scores (both regarding the morning, afternoon, and pooled mean scores), and between sleep disturbances and the morning mean score.

CONCLUSIONS

French medical students have a poor sleep quality, correlating with academic performances, and present a poor knowledge of basic sleep rules. These findings are a call to improve medical training schedules and to develop prevention and training programs.

Worldwide estimation of restless legs syndrome: a systematic review and meta-analysis of prevalence in the general adult population

This systematic review, meta-analysis and meta-regression assessed the prevalence of restless legs syndrome (RLS) in the general adult population. Studies identified in Scopus, PubMed, Web of Science, and PsycInfo between January 2000 and February 2022 were included if they used a case-control or cross-sectional design and reported data regarding the prevalence of RLS. The protocol was pre-registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022300709). A total of 97 studies including 483,079 participants from 33 different countries met the eligibility criteria. The Newcastle Ottawa Scale was used to evaluate the methodological quality, and the fill-and-trim method was used to correct probable publication bias, while the jack-knife method was performed to assess small study effect. The corrected overall pooled prevalence of RLS was 3% (95% confidence interval [CI] 1.4%-3.8%). The pooled prevalence of RLS syndrome was affected by methodological quality (no data from non-respondents in the included studies), gender (higher among women), study design (lower prevalence in case-control versus cohort and cross-sectional studies). The figures for corrected pooled prevalence among men, women, alcohol consumers and smokers were 2.8% (95% CI 2%-3.7%); 4.7% (95% CI 3.2%-6.3%); 1.4% (95% CI 0%-4.2%); and 2.7% (95% CI 0%-5.3%), respectively. The prevalence among male and female participants was lower in community-based versus non-community-based studies. Moreover, the prevalence was higher in developed versus developing countries and among elders versus adults. In conclusion, RLS is a common disorder in the general adult population, with a higher prevalence in women; however, prevalence data are affected by study design and quality.

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.

The Effects of Pharmacological Treatment of Nightmares: A Systematic Literature Review and Meta-Analysis of Placebo-Controlled, Randomized Clinical Trials

Nightmares are highly prevalent and distressing for the sufferer, which underlines the need for well-documented treatments. A comprehensive literature review and meta-analysis of the effects of different pharmacological placebo-controlled randomized clinical trials, covering the period up to 1 December 2022, was performed. Searches were conducted in PubMed, Embase, Web of Science, PsychInfo, Cinahl, and Google Scholar, resulting in the identification of 1762 articles, of which 14 met the inclusion criteria: pharmacological intervention of nightmares, based on a placebo-controlled randomized trial published in a European language, reporting outcomes either/or in terms of nightmare frequency, nightmare distress, or nightmare intensity, and reporting sufficient information enabling calculation of effect sizes. Most studies involved the effect of the α₁-adrenergic antagonist prazosin in samples of veterans or soldiers suffering from posttraumatic stress disorder. Other medications used were hydroxyzine, clonazepam, cyproheptadine, nabilone, and doxazosin. The vast majority of studies were conducted in the USA. The studies comprised a total of 830 participants. The Clinician-Administered PTSD Scale was the most frequently used outcome measure. The results showed an overall effect size of Hedges' g = 0.50 (0.42 after adjustment for publication bias). The synthetic cannabinoid nabilone (one study) showed the highest effect size (g = 1.86), followed by the histamine H₁-antagonist hydroxyzine (one study), and prazosin (10 studies), with effect sizes of g = 1.17 and g = 0.54, respectively. Findings and limitations are discussed, and recommendations for future studies are provided.

Prescription of Silexan Is Associated with Less Frequent General Practitioner Repeat Consultations Due to Disturbed Sleep Compared to Benzodiazepine Receptor Agonists: A Retrospective Database Analysis

The aim of the present study was to analyze the association between the prescription of Silexan and the recurrence of general practitioner (GP) repeat consultations because of disturbed sleep versus benzodiazepine receptor agonists including zolpidem, zopiclone, and zaleplon (Z-drugs). This retrospective cohort study was based on data from the IQVIA Disease Analyzer (DA) database. The study included adult patients treated by 1284 GPs in Germany with a documented sleep disorder and their first prescription of Silexan or Z-drug (prescription between January 2010 and October 2020). The recurrence of seeking medical advice because of sleep disorders in the 15-365 days after the first prescription was evaluated. Multivariate regression models were used, adjusted for age, sex, insurance status, and defined co-diagnoses. Data were available for 95,320 (Silexan: 5204; Z-Drug: 90,526) patients. In total, 15.6% of the Silexan patients and 28.6% of the Z-drug patients had a further documented GP consultation because of a sleep disorder. Silexan prescription was associated with significantly lower odds of recurrent sleep disorder diagnosis in the 15-365 days after the index date (Odds Ratio (OR): 0.56; 95% confidence intervals (CI): 0.51-0.60), although mental burden levels appeared higher in this group. Our study shows that the prescription of Silexan to adult patients consulting GPs for disturbed sleep results in less frequent repeat consultations than Z-drugs. This may support Silexan's role as an efficacious, self-enabling, well-tolerated, and sustained treatment option. Because Silexan is a proven anxiolytic, its impact in improving undiagnosed anxiety disorders may have had a lasting effect for certain patients.

Parasomnias during trans-meridian and long-distance travel: Critical literature review and clinical practice recommendations

Parasomnias are undesirable events that occur during sleep. They can be classified into rapid eye movement parasomnias and non-rapid eye movement parasomnias. Those who experience parasomnias may be anxious about travel for many reasons, including the occurrence of unwanted events during the trip, increased exposure to environmental trigger factors, and the propensity for harm to occur due to unfamiliar surroundings while travelling. There is a paucity of literature examining this area. This review summarizes the relevant literature and the clinical experience of the authors to compile clinical practice recommendations. The clinical features of parasomnias and how they relate to trans-meridian and long-distance travel are described. Triggers for non-rapid eye movement parasomnias, particularly the use of sedative hypnotic drugs, alcohol, drug withdrawal, sleep deprivation, emotional stress and environmental stimulations, are described. Management of parasomnias whilst travelling is reviewed, with a particular focus on trigger minimalization. The role for clonazepam and melatonin is outlined. At the pre-travel health consultation, the physician is strongly advised to screen the traveller for co-morbid sleep conditions, which exacerbate parasomnias. Areas for further research are explored, including the extent to which these sleep disorders impact on the travel experience.

The Influence of Sleep Talking on Nocturnal Sleep and Sleep-Dependent Cognitive Processes

BACKGROUND

Sleep talking (ST) is characterized by the production of unaware verbal vocal activations (VBs) during sleep. ST seems potentially linked to linguistic and memory consolidation processes. However, sleep and dream characteristics and the relationship between verbal vocalizations (VBs) and cognitive functions are still unknown. Our study aimed to investigate qualitative sleep and dream features in sleep talkers (STs) compared to healthy subjects (CNTs) through retrospective and longitudinal measures and explore the relationship between ST and memory consolidation.

METHODS

We recruited N = 29 STs and N = 30 CNTs (age range of 18-35). Participants recorded their dreams and filled out sleep logs for seven consecutive days. Vocal activations of STs were audio-recorded. On the eighth day, we administered a word-pair task.

RESULTS

We showed that STs had significantly worse self-reported sleep quality. VBs were positively correlated with sleep fragmentation and negatively associated with the oneiric emotional load. No difference between groups was found in the memory consolidation rate.

CONCLUSIONS

Although ST is a benign phenomenon, we revealed that ST is associated with more sleep alterations and lower emotional intensity of dreams. In this vein, we support that ST depends on sleep fragmentation and could represent a potential window into sleep-dependent cognitive processes.

More than sleepiness: prevalence and relevance of nonclassical symptoms of obstructive sleep apnea

PURPOSE OF REVIEW

The purpose of this review is to describe the nonclassical symptoms and manifestations occurring in patients with obstructive sleep apnea (OSA), both from a standpoint of prevalence and in terms of clinical relevance. Particular emphasis will be given to nightmares, comorbid insomnia, restless legs syndrome and periodic limb movement disorder, bruxism, morning headache, nocturia, acid reflux, chronic cough and dysphagia.

RECENT FINDINGS

A review of the recent literature suggests that nonclassical symptoms have a high prevalence, are underestimated, and can interact with quality of life. Although these disturbances may occur together by mere coincidence, they may interact reciprocally. However, the degree of symptoms is not always correlated with OSA severity.

SUMMARY

OSA is a heterogeneous disease with variable clinical manifestations. This review highlights the need for detailed evaluation of patients with OSA to diagnose other important sleep disorders and clinical manifestations, given their frequent association.

NREM Sleep Parasomnias Commencing in Childhood: Trauma and Atopy as Perpetuating Factors

Objective/Background: Phenotyping of non-rapid-eye-movement (NREM) parasomnias is currently poorly undertaken. This study aimed to determine whether there are differences phenotypically among childhood-, adolescent-, and adult-onset NREM parasomnias continuing into and presenting in adulthood. Patients/Methods: A retrospective, cohort study of patients presenting with NREM parasomnia between 2008 and 2019 (n = 307) was conducted. Disorders included sleepwalking (n = 231), night terrors (n = 150), sexualised behaviour in sleep (n = 50), and sleep-related eating disorder (n = 28). Results: Compared to the adult-onset NREM behaviours group, the childhood- and adolescent-onset groups were more likely to have a family history of NREM behaviours (p < 0.001), experience a greater spectrum of NREM disorders (p = 0.001), and report a history of sleep-talking significantly more frequently (p = 0.014). Atopy was most prevalent in the childhood-onset group (p = 0.001). Those with childhood-onset NREM parasomnias were significantly more likely to arouse from N3 sleep on video polysomnography (p = 0.0003). Psychiatric disorders were more likely to be comorbid in the adult-onset group (p = 0.012). A history of trauma coinciding with onset of NREM behaviours was significantly more common in the childhood- and adolescent-onset groups (p < 0.001). Conclusions: Significant differences exist across childhood-, adolescent-, and adult-onset NREM parasomnia presenting in adulthood. This study suggests that adult-onset slow-wave sleep disorders may be confounded by psychiatric disorders resulting in nocturnal sleep disruption and that unresolved traumatic life experiences perpetuate NREM disorders arising in childhood and comprise one of the strongest external risk factors for triggering and perpetuating these disorders in adolescence.

Sleep terrors in early childhood and associated emotional-behavioral problems

STUDY OBJECTIVES

While sleep terrors are associated with emotional-behavioral problems in school-aged children and adults, little is known about these associations in early childhood, when sleep terrors prevalence is at its highest. Moreover, studies using a longitudinal design and controlling for confounding variables are scarce. This study's objective was to determine whether the frequency of sleep terrors in toddlers predicts emotional-behavioral problems during the preschool years.

METHODS

Participants (n = 324) were enrolled in the prospective Maternal Adversity Vulnerability and Neurodevelopment cohort study. The frequency of sleep terrors in children was assessed at 12, 18, 24, and 36 months using maternal reports. Children's emotional-behavioral problems were measured at 48 and 60 months using the Child Behavior Checklist. Relevant confounders linked to the child, mother, and environment were also taken into consideration.

RESULTS

The frequency of sleep terrors was relatively stable across early childhood (16.7-20.5%). A generalized estimating equation revealed that the frequency of sleep terrors in early childhood was associated with increased emotional-behavioral problems at 4 and 5 years of age, more specifically with internalizing problems (P < .001), after controlling for child's sex, time point, family socioeconomic status, maternal depressive symptoms, and nighttime sleep duration. The frequency of sleep terrors was further associated with the emotionally reactive, anxious/depressed, and somatic complaints scales (P < .01).

CONCLUSIONS

This longitudinal study provides further support for a high prevalence of sleep terrors in early childhood. Our findings show meaningful associations between higher frequency of sleep terrors and emotional-behavioral problems as early as toddlerhood, especially internalizing problems.

CITATION

Laganière C, Gaudreau H, Pokhvisneva I, et al. Sleep terrors in early childhood and associated emotional-behavioral problems. J Clin Sleep Med. 2022;18(9):2253-2260.

Sleep-Related Drug Therapy in Special Conditions: Children

Pharmacologic treatment of the most common pediatric sleep disorders lacks evidence, and alternative methods, which have been proved to alleviate the symptoms, are preferred in most cases. The implementation of specific guidelines is of great importance because sleep disorders in children are not rare and they can negatively affect children's development and their cognitive and social skills. This article summarizes the current therapeutic management of sleep disorders in children, bearing in mind the absence of evidence-based guidelines on this topic.

What respiratory physicians should know about parasomnias

Parasomnias have significant quality-of-life, prognostic and potentially forensic implications for patients and their bed-partners. Identifying key clinical features will accelerate diagnosis and appropriate management for these patients. Parasomnias are undesirable physical events or experiences that arise out of, or during, sleep. They can include movements, behaviours, emotions, perceptions, dreams or autonomic nervous system activity. While more common during childhood, they can persist into, or present de novo, during adulthood. Parasomnias can arise out of non-rapid eye movement (NREM) sleep, as in confusional arousals, sleepwalking, sleep terrors or sleep-related eating disorder, or out of REM sleep, as in REM behaviour disorder, recurrent isolated sleep paralysis or nightmare disorder. Sleep-related hypermotor epilepsy is an important differential diagnosis to consider in patients presenting with a parasomnia. A thorough clinical history, including a collateral history if available, is crucial to identify characteristic clinical features. Video polysomnography is useful to identify macro- and micro-sleep architectural features, characteristic behavioural events, and any concomitant sleep pathologies. Treatment of parasomnias involves a combined approach of pharmacological and non-pharmacological intervention, including safety measures, sleep hygiene and medicines such as clonazepam or melatonin to improve sleep consolidation and reduce behavioural activity. As parasomnias can not only be disruptive for the patient and their bed-partner but have important prognostic or forensic consequences, an understanding of their pathophysiology, clinical features and management is valuable for any respiratory physician who may encounter them.

Educational aims

To understand the common features of NREM and REM parasomnias.To differentiate between the causes of motor behaviours during sleep.To discuss the treatment approach for NREM and REM parasomnias.

Sleep terrors-A parental nightmare

Sleep terrors (STs) are sleep disorders characterized by abrupt arousal from sleep with autonomic hyperactivity and inappropriate behavior. Though a common condition in childhood that usually affects children between 4 and 12 years of age, STs, however, may be present even in adulthood. The exact etiology of STs is not known yet, however, several hypotheses have been proposed over the years, identifying some potential genetic, neurodevelopmental, or other causes. Nevertheless, a useful pathophysiological model identified a common cascade of predisposing, priming, and precipitating factors, which could help to explain and sometimes prevent STs. Establishing a correct diagnosis is mandatory for appropriate management, as several conditions (such as other parasomnias or nocturnal seizures) may mimic STs. Furthermore, we also described some conditions which can be comorbid to STs, like some medical or psychological disorders. A number of treatment options have been proposed, ranging from only sleep hygiene practices to pharmacological therapies; we reviewed some of the most prominent ones. In spite of the fact that STs have long been considered benign disorders, which tend to reduce spontaneously over the years, they may have unexpected consequences on the child but also on the caregivers.

Sleep talking versus sleep moaning: electrophysiological patterns preceding linguistic vocalizations during sleep

STUDY OBJECTIVES

Sleep talking (ST) has been rarely studied as an isolated phenomenon. Late investigations over the psycholinguistic features of vocal production in ST pointed to coherence with wake language formal features. Therefore, we investigated the EEG correlates of Verbal ST as the overt manifestation of sleep-related language processing, with the hypothesis of shared electrophysiological correlates with wake language production.

METHODS

From a sample of 155 Highly frequent STs, we recorded 13 participants (age range 19-30 years, mean age 24.6 ± 3.3; 7F) via vPSG for at least two consecutive nights, and a total of 28 nights. We first investigated the sleep macrostructure of STs compared to 13 age and gender-matched subjects. We then compared the EEG signal before 21 Verbal STs versus 21 Nonverbal STs (moaning, laughing, crying, etc.) in six STs reporting both vocalization types in Stage 2 NREM sleep.

RESULTS

The 2 × 2 mixed analysis of variance Group × Night interaction showed no statistically significant effect for macrostructural variables, but significant main effects for Group with lower REM (%), total sleep time, total bedtime, sleep efficiency index, and greater NREM (%) for STs compared to controls. EEG statistical comparisons (paired-samples Student's t-test) showed a decrement in power spectra for Verbal STs versus Nonverbal STs within the theta and alpha EEG bands, strongly lateralized to the left hemisphere and localized on centro-parietal-occipitals channels. A single left parietal channel (P7) held significance after Bonferroni correction.

CONCLUSIONS

Our results suggest shared neural mechanisms between Verbal ST and language processing during wakefulness and a possible functional overlapping with linguistic planning in wakefulness.

Dream-enactment behaviours during the COVID-19 pandemic: an international COVID-19 sleep study

There has been increasing concern about the long-term impact of coronavirus disease 2019 (COVID-19) as evidenced by anecdotal case reports of acute-onset parkinsonism and the polysomnographic feature of increased rapid eye movement sleep electromyographic activity. This study aimed to determine the prevalence and correlates of dream-enactment behaviours, a hallmark of rapid eye movement sleep behaviour disorder, which is a prodrome of α-synucleinopathy. This online survey was conducted between May and August 2020 in 15 countries/regions targeting adult participants (aged ≥18 years) from the general population with a harmonised structured questionnaire on sleep patterns and disorders, COVID-19 diagnosis and symptoms. We assessed dream-enactment behaviours using the Rapid Eye Movement Sleep Behaviour Disorder Single-Question Screen with an additional question on their frequency. Among 26,539 respondents, 21,870 (82.2%) answered all items that were analysed in this study (mean [SD] age 41.6 [15.8] years; female sex 65.5%). The weighted prevalence of lifetime and weekly dream-enactment behaviours was 19.4% and 3.1% and were found to be 1.8- and 2.9-times higher in COVID-19-positive cases, respectively. Both lifetime and weekly dream-enactment behaviours were associated with young age, male sex, smoking, alcohol consumption, higher physical activity level, nightmares, COVID-19 diagnosis, olfactory impairment, obstructive sleep apnea symptoms, mood, and post-traumatic stress disorder features. Among COVID-19-positive cases, weekly dream-enactment behaviours were positively associated with the severity of COVID-19. Dream-enactment behaviours are common among the general population during the COVID-19 pandemic and further increase among patients with COVID-19. Further studies are needed to investigate the potential neurodegenerative effect of COVID-19.

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.

Worsening sleep quality across the lifespan and persistent sleep disturbances in persons with opioid use disorder

STUDY OBJECTIVES

Individuals with opioid use disorder (OUD) may experience worsening sleep quality over time, and a subset of individuals may have sleep disturbances that precede opioid use and do not resolve following abstinence. The purpose of the present study was to (1) collect retrospective reports of sleep across the lifespan and (2) identify characteristics associated with persistent sleep disturbance and changes in sleep quality in persons with OUD.

METHODS

Adults with OUD (n = 154) completed a cross-sectional study assessing current and past sleep disturbance, opioid use history, and chronic pain. Repeated-measures analysis of variance was used to examine changes in retrospectively reported sleep quality, and whether changes varied by screening positive for insomnia and/or chronic pain. Multivariate linear regression analyses were used to identify additional correlates of persistent sleep disturbance.

RESULTS

Participants reported that their sleep quality declined over their lifespan. Changes in reported sleep over time varied based on whether the individual screened positive for co-occurring insomnia and/or chronic pain. In regression analyses, female sex (β = 0.16, P = .042), a greater number of treatment episodes (β = 0.20, P = .024), and positive screens for chronic pain (β = 0.19, P = .018) and insomnia (β=0.22, P = .013) were associated with self-reported persistent sleep disturbance. Only a portion of participants who screened positive for sleep disorders had received a formal diagnosis.

CONCLUSIONS

OUD treatment providers should routinely screen for co-occurring sleep disturbance and chronic pain. Interventions that treat co-occurring OUD, sleep disturbance, and chronic pain are needed.

CITATION

Ellis JD, Mayo JL, Gamaldo CE, Finan PH, Huhn AS. Worsening sleep quality across the lifespan and persistent sleep disturbances in persons with opioid use disorder. J Clin Sleep Med. 2022;18(2):587-595.

Comorbid parasomnias in narcolepsy and idiopathic hypersomnia: more REM than NREM parasomnias

STUDY OBJECTIVES

To assess the frequency, determinants and clinical impact of clinical NREM and REM parasomnias in adult patients with narcolepsy type 1 (NT1), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH) compared to healthy controls.

METHODS

Familial and past and current personal parasomnias were assessed by questionnaire and medical interviews in 710 patients (220 NT1, 199 NT2, and 221 IH) and 595 healthy controls.

RESULTS

Except for sleep-related eating disorder (SRED), current NREM parasomnias were rare in all patient groups and controls. SRED was more frequent in NT1 patients (7.9%, vs. 1.8% in NT2 patients, 2.1% in IH patients and 1% in controls) and associated with disrupted nighttime sleep (odds ratio [OR] = 3.9) and nocturnal eating in full awareness (OR = 6.9) but not with sex. Clinical REM sleep behavior disorder (RBD) was more frequent in NT1 patients (41.4%, half being violent) than in NT2 patients (13.2%) and affected men more often than women (OR = 2.4). It was associated with disrupted nighttime sleep, depressive symptoms and antidepressant use. Frequent (>1/week) nightmares were reported by 39% of patients with NT1, 29% with NT2 and 27.8% with IH (vs. 8.3% in controls) and were associated with depressive symptoms in narcolepsy. No parasomnia (except sleep-related hallucinations) worsened daytime sleepiness.

CONCLUSIONS

In patients with central disorders of hypersomnolence, comorbid NREM parasomnias (except SRED) are rare and do not worsen sleepiness. In contrast, REM parasomnias are prevalent (especially in NT1) and associated with male sex, disrupted nighttime sleep, depressive symptoms and antidepressant use.

Do animals dream?

The understanding of biological functions of sleep has improved recently, including an understanding of the deep evolutionary roots of sleep among animals. However, dreaming as an element of sleep may be particularly difficult to address in non-human animals because in humans dreaming involves a non-wakeful form of awareness typically identified through verbal report. Here, we argue that parallels that exist between the phenomenology, physiology, and sleep behaviors during human dreaming provide an avenue to investigate dreaming in non-human animals. We review three alternative measurements of human dreaming - neural correlates of dreaming, 'replay' of newly-acquired memories, and dream-enacting behaviors - and consider how these may be applied to non-human animal models. We suggest that while animals close in brain structure to humans (such as mammals and birds) may be optimal models for the first two of these measurements, cephalopods, especially octopuses, may be particularly good candidates for the third.

Evaluation of the effects of shift work on parasomnia prevalence

Shift work is increasingly common in industrialized countries but is associated with numerous health problems, especially sleep disorders. This study compared the frequency of NREM (confusional arousal, sleep terrors, sleepwalking, sleep-related eating disorder), REM parasomnias (REM sleep behavior disorder, nightmare disorder), and isolated symptoms/normal variants (sleeptalking) between shift workers and daytime workers. A total of 1473 participants in 3 different professional groups and working different shift schedules (daytime, night, or rotating shifts) were included. Participants completed a questionnaire consisting of 132 questions about parasomnia, occupational stress, history of occupational and traffic accidents, depression, and other sleep disorders. The lifetime parasomnia prevalence was 43.7% and the 1-year parasomnia prevalence was 24.4% overall. The 1-year parasomnia prevalence was 27.5% among shift workers and 13% among daytime workers. This rate was highest among rotating shift workers (27.9%), followed by night shift workers (21.2%), and lowest in daytime workers (13%) (P < .001). The most common parasomnias reported were sleep terrors, confusional arousals, and sleeptalking. Parasomnia prevalence rates among workers with and without a history of occupational accidents were 43.7% and 24.2%, while those of workers with and without a history of car accidents were 47.4% and 23.8%, respectively (P < .001). Shift work was associated with higher parasomnia prevalence. Working rotating shifts in particular was an independent risk factor for parasomnia. The parasomnias most frequently associated with shift work were confusional arousal, sleeptalking, and sleep terrors. It should be kept in mind that higher parasomnia rates may increase the risk of occupational and traffic accidents in this population.

Epidemiology of disturbing dreams in a diverse US sample

STUDY OBJECTIVES

Disturbing dreams are a common complaint among trauma survivors, but little epidemiological research exists to document the frequency in the general population. In addition, information about their occurrence in diverse adults is lacking.

METHODS

Using the Collaborative Psychiatric Epidemiology Surveys we had the unique opportunity to examine disturbing dreams in a diverse sample of adults in the US. Disturbing dreams were measured in three different variables including trauma dreams, dreams of the worst event, and dreams of separation. A fourth variable was created to assess for any disturbing dream reported across the three categories.

RESULTS

Disturbing dream prevalence varied in the overall sample (N = 20,013) based on the assessment question. Dreams of trauma was 2.01% in the overall sample, dreams of the worst event was 7.21% and dreams of separation was 1.73%. Prevalence rates of all dream variables varied by racial and ethnic group membership, gender, and age. Odds ratios were also calculated for the three variables of interest by racial and ethnic group with significant differences emerging. Women had significantly higher rates of disturbing dreams in all variables assessed (p < 0.01). Older adults reported significantly lower rates of disturbing dreams compared to younger and middle-aged adults (p < 0.001).

CONCLUSIONS

This study establishes prevalence rates for disturbing dreams in a diverse sample of US adults. Understanding the prevalence can aid in reducing barriers to care for evidence-based treatments currently underutilized.

Mandibular advancement device as treatment trial for catathrenia (nocturnal groaning)

STUDY OBJECTIVES

Catathrenia is a rare disease, classified as isolated symptoms and normal variants under sleep-related breathing disorders in the International Classification of Sleep Disorders, third edition. Because of its rarity, the research on its pathogenesis and treatment is insufficient. This study aimed to evaluate whether the mandibular advancement device (MAD) could be considered an alternative treatment trial and if so, to explore factors predicting its effectiveness.

METHODS

Thirty patients (12 males and 18 females, aged 16 to 67 years) with catathrenia participated in the study. They underwent standard clinical evaluation, questionnaires, physical examinations, craniofacial evaluations, video-polysomnography, and imaging of the upper airway before and after the insertion of the MAD. Groaning index (GI, groaning episodes per hour of sleep) and apnea-hypopnea index (AHI) were evaluated and anatomic factors predicting effectiveness were explored.

RESULTS

The sleep efficiency of most patients was higher than 80% and groaning was present throughout all stages of sleep. With the insertion of MAD, GI decreased significantly from 5.8 (2.7, 14.3) to 2.8 (1.3, 12.2) events/h (P = 0.014). Age had a negative effect on efficacy. Mandibular repositioning of MAD, especially the amount of vertical opening and changes of cross-sectional area of hypopharynx, was positively related with efficacy.

CONCLUSIONS

The MAD could be considered a possible treatment trial for those seeking treatment for groaning.

CLINICAL TRIAL REGISTRATION

Registry: Chinese Clinical Trial Registry; Identifier: ChiCTR-COC-17013239; URL: http://www.chictr.org.cn/showproj.aspx?proj=22286.

Psychometric properties of the Disturbing Dream and Nightmare Severity Index-Korean version

STUDY OBJECTIVES

This study aimed to examine psychometric properties of the Disturbing Dream and Nightmare Severity Index (DDNSI) in individuals aged between 18 and 39.

METHODS

All participants (n = 674) were asked to complete the DDNSI, including the modified Nightmare Effects Survey. Additionally, 109 participants were tested for test-retest reliability after 3 months. Among our sample, 229 (33.9%) reported having at least 1 nightmare per month.

RESULTS

Internal consistency was evaluated for the total sample (Cronbach's α = .920) and separately for individuals reporting more than once per month (Cronbach's α = .755). Test-retest reliability after 3 months was .705. Convergent validity of the DDNSI with Nightmare Effects Survey was also satisfactory (r = .638, P < .001). Finally, exploratory factor analysis was conducted to explore the construct of the DDNSI, and results indicated that it consisted of 2 factors, nightmare frequency and nightmare distress [χ²(df) = 2.241(1) ∆χ² (∆df) = 155.575(4), Tucker-Lewis incremental fit index = .980, root mean square error of approximation (90% confidence interval) = .074 (0, .208), standardized root-mean-square residual = .011].

CONCLUSIONS

The DDNSI is a reliable measure of nightmare severity that can be used in various settings.

Insomnia - A Heterogenic Disorder Often Comorbid With Psychological and Somatic Disorders and Diseases: A Narrative Review With Focus on Diagnostic and Treatment Challenges

Patients with insomnia complain of problems with sleep onset or sleep maintenance or early morning awakenings, or a combination of these, despite adequate opportunity and circumstances for sleep. In addition, to fulfill the diagnostic criteria for insomnia the complaints need to be associated with negative daytime consequences. For chronic insomnia, the symptoms are required to be present at least 3 days per week for a duration of at least 3 months. Lastly, for insomnia to be defined as a disorder, the sleep complaints and daytime symptoms should not be better explained by another sleep disorder. This criterion represents a diagnostic challenge, since patients suffering from other sleep disorders often complain of insomnia symptoms. For instance, insomnia symptoms are common in e.g., obstructive sleep apnea and circadian rhythm sleep-wake disorders. It may sometimes be difficult to disentangle whether the patient suffers from insomnia disorder or whether the insomnia symptoms are purely due to another sleep disorder. Furthermore, insomnia disorder may be comorbid with other sleep disorders in some patients, e.g., comorbid insomnia and sleep apnea (COMISA). In addition, insomnia disorder is often comorbid with psychological or somatic disorders and diseases. Thus, a thorough assessment is necessary for correct diagnostics. For chronic insomnia disorder, treatment-of-choice is cognitive behavioral therapy, and such treatment is also effective when the insomnia disorder appears comorbid with other diagnoses. Furthermore, studies suggest that insomnia is a heterogenic disorder with many different phenotypes or subtypes. Different insomnia subtypes may respond differently to treatment, but more research on this issue is warranted. Also, the role of comorbidity on treatment outcome is understudied. This review is part of a Research Topic on insomnia launched by Frontiers and focuses on diagnostic and treatment challenges of the disorder. The review aims to stimulate to more research into the bidirectional associations and interactions between insomnia disorder and other sleep, psychological, and somatic disorders/diseases.

Disorders of Arousal: A Chronobiological Perspective

Non-rapid eye movement (NREM) sleep parasomnias are characterized by motor and emotional behaviors emerging from incomplete arousals from NREM sleep and they are currently referred to as disorders of arousal (DoA). Three main clinical entities are recognized, namely confusional arousal, sleep terror and sleepwalking. DoA are largely present in pediatric populations, an age in which they are considered as transitory, unhabitual physiological events. The literature background in the last twenty years has extensively shown that DoA can persist in adulthood in predisposed individuals or even appear de novo in some cases. Even though some episodes may arise from stage 2 of sleep, most DoA occur during slow wave sleep (SWS), and particularly during the first two sleep cycles. The reasons for this timing are linked to the intrinsic structure of SWS and with the possible influence on this sleep phase of predisposing, priming and precipitating factors for DoA episodes. The objective of this paper is to review the intrinsic sleep-related features and chronobiological aspects affecting SWS, responsible for the occurrence of the majority of DoA episodes during the first part of the night.

Prevalence and associated factors of circadian rhythm sleep-wake disorders and insomnia among visually impaired Japanese individuals

BACKGROUND

Although earlier studies have demonstrated that circadian rhythm sleep-wake disorders (CRSWD) are more prevalent in visually impaired individuals, the actual prevalence of CRSWD and insomnia among the visually impaired Japanese population remains unclear. The aim of this cross-sectional, telephone-based study was to estimate the prevalence of CRSWD and insomnia, and explore factors associated with CRSWD and insomnia among visually impaired Japanese individuals.

METHODS

A nationwide telephone survey was conducted among visually-impaired individuals through local branches of the Japan Federation of the Blind. In total, 157 visually impaired individuals were eligible for this study. Demographic information and information about visual impairments, lifestyle, and sleep patterns were assessed using questionnaires and subsequent telephone interviews. CRSWD and insomnia were defined according to the International Classification of Sleep Disorders-Third Edition criteria.

RESULTS

The prevalence of CRSWD in visually impaired individuals was 33.1%. Among those with CRSWD, a non-24-h/irregular sleep-wake rhythm type was the most frequently observed (26.8%), followed by an advanced sleep-wake phase type and a delayed sleep-wake phase type (3.8 and 2.5%, respectively). Furthermore, 28.7% of the visually impaired individuals were found to have insomnia. In the visually impaired individuals, the absence of light perception, unemployment, living alone, and use of hypnotics were significantly associated with CRSWD, whereas only the use of hypnotics was extracted as a marginally associated factor of insomnia.

CONCLUSIONS

CRSWD and insomnia were highly prevalent in visually impaired Japanese individuals. The presence of CRSWD among the visually impaired individuals was associated with a lack of light perception and/or social zeitgebers.

Case Report: Parasomnia Overlap Disorder Induced by Obstructive Sleep Hypopnea Apnea Syndrome: A Case Report and Literature Review

Obstructive sleep apnea hypopnea syndrome (OSAHS) and parasomnia overlap disorder (POD) are types of sleep disorders. When the symptoms of both conditions coexist, the POD symptoms are most likely caused by OSAHS. In these cases, the symptoms of POD will be relieved when OSAHS is effectively treated. We refer to these cases as symptomatic POD (related to OSAHS), which differs in pathophysiology, complications, and treatment from idiopathic POD. It is important to note that the treatment for idiopathic POD may aggravate the symptoms of OSAHS. In this case, we used video polysomnography (v-PSG) on a POD patient with suspected OSAHS to distinguish idiopathic POD from symptomatic POD, to inform the appropriate treatment course. The video results and clinical features lead us to diagnose symptomatic POD, and we treated the patient with auto-set continuous positive airway pressure to address their OSAHS. This course of treatment resolved all POD-related symptoms. Here, we discuss this case and review the relevant literature. This report highlights the importance of the use of v-PSG in the clinical diagnosis, differential diagnosis, and subsequent treatment of POD.

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.

Nightmare experience and personality disorder functioning styles in healthy volunteers and nightmare disorder patients

Nightmares are prevalent in psychiatric disorders, and personality disorder features might be associated with nightmare experience, especially in nightmare disorder patients. The authors invited 219 healthy volunteers and 118 nightmare disorder patients to undergo tests of the Nightmare Experience Questionnaire (NEQ), the Parker Personality Measure (PERM), and the Plutchik-van Praag Depression Inventory. Compared to healthy volunteers, nightmare disorder patients scored significantly higher on annual nightmare frequency and NEQ Physical Effect, Negative Emotion, Meaning Interpretation, and Horrible Stimulation, and higher on PERM Paranoid, Schizotypal, Borderline, Histrionic, Narcissistic, Avoidant, and Dependent styles. Borderline, Schizotypal, and Passive-Aggressive styles in healthy volunteers and Dependent, Avoidant, Histrionic, and Paranoid in patients were significant predictors of some NEQ scales. Higher annual nightmare frequency, higher scale scores of nightmare experience and personality disorder styles, and more associations between the two were found in nightmare disorder patients, implying the need for personality-adjustment therapy for nightmare disorder.