A review of nighttime eating disorders

Associations between self-reported parasomnias and psychiatric illness in 370,000 patients with sleep disorders

AIM

To assess self-reported parasomnias in patients with sleep disorders and explore relationships with psychiatric illness, comorbidities, subjective sleep assessments, and polysomnographic study results.

METHODS

Results from intake questionnaires and polysomnographic assessments, collected from 240 sleep centers across 30 US states between 2004 and 2019, were analyzed retrospectively. Of 540,000 total patients, 371,889 who answered parasomnia-specific questions were included. Patients responding "often" or "always" to parasomnia-specific questions were considered "symptom-positive," whereas a "few times" or "never" were considered "symptom-negative" (controls).

RESULTS

The study sample was 54.5% male with mean age 54 years (range, 2-107 years). Frequencies for the different parasomnias were 16.0% for any parasomnia, 8.8% for somniloquy, 6.0% for hypnagogic hallucinations, 4.8% for sleep-related eating disorder, 2.1% for sleep paralysis, and 1.7% for somnambulism. Frequent parasomnias were highly associated with diagnosed depression (odds ratio = 2.72). All parasomnias were associated with being younger and female and with symptoms of depression, anxiety, insomnia, restless legs, pain, medical conditions, fatigue, and sleepiness. Associations with objective sleep metrics showed characteristics of consolidated sleep and differentiated weakly between nonrapid eye movement sleep and rapid eye movement sleep parasomnias. Machine learning accurately classified patients with parasomnia versus controls (balanced accuracies between 71% and 79%). Benzodiazepines, antipsychotics, and opioids increased the odds of experiencing parasomnias, while antihistamines and melatonin reduced the odds. Z-drugs were found to increase the likelihood of a sleep-related eating disorder.

CONCLUSION

Our findings suggest that parasomnias may be clinically relevant, yet understudied, symptoms of depression and anxiety. Further investigation is needed to quantify the nature of multimorbidity, including causality and implications for diagnosis and treatment.

The Parasomnias

Parasomnias usually present in childhood and resolve spontaneously. The diagnosis of non-rapid eye movement-related parasomnias is mainly based on clinical descriptors and can be challenging. Rapid eye movement-related parasomnias may index an underlying psychiatric disorder. Even if benign, parasomnias can affect quality of life. Pediatricians and child psychiatrists should be familiarized with these sleep disorders and suggest adequate sleep hygiene, avoidance of sleep deprivation, and regular bedtimes even on weekends as the first step in management of these disorders. Clinicians should pursue the opportunity for tailoring treatments and consider referral to a sleep expert when indicated.

Sleep Profiles in Eating Disorders: A Scientometric Study on 50 Years of Clinical Research

Sleep and diet are essential for maintaining physical and mental health. These two factors are closely intertwined and affect each other in both timing and quality. Eating disorders, including anorexia nervosa and bulimia nervosa, are often accompanied by different sleep problems. In modern society, an increasing number of studies are being conducted on the relationship between eating disorders and sleep. To gain a more comprehensive understanding of this field and highlight influential papers as well as the main research domains in this area, a scientometric approach was used to review 727 publications from 1971 to 2023. All documents were retrieved from Scopus through the following string "TITLE-ABS (("sleep" OR "insomnia") AND ("anorexia nervosa" OR "bulimia nervosa" OR "binge eating" OR "eating disorder*") AND NOT "obes*") AND (LIMIT-TO (LANGUAGE, "English"))". A document co-citation analysis was applied to map the relationship between relevant articles and their cited references as well as the gaps in the literature. Nine publications on sleep and eating disorders were frequently cited, with an article by Vetrugno and colleagues on nocturnal eating being the most impactful in the network. The results also indicated a total of seven major thematic research clusters. The qualitative inspection of clusters strongly highlights the reciprocal influence of disordered eating and sleeping patterns. Researchers have modelled this reciprocal influence by taking into account the role played by pharmacological (e.g., zolpidem, topiramate), hormonal (e.g., ghrelin), and psychological (e.g., anxiety, depression) factors, pharmacological triggers, and treatments for eating disorders and sleep problems. The use of scientometric perspectives provides valuable insights into the field related to sleep and eating disorders, which can guide future research directions and foster a more comprehensive understanding of this important area.

Metabolic, behavioral health, and disordered eating comorbidities associated with obesity in pediatric patients: An Obesity Medical Association (OMA) Clinical Practice Statement 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children. This CPS will be followed by a companion CPS covering further comorbidities, including genetics and social consequences related to overweight and obesity. These CPSs are intended to provide clinicians with an overview of clinical practices applicable to children and adolescents with body mass indices greater than or equal to the 95th percentile for their ages, particularly those with adverse consequences resulting from increased body mass. The information in this CPS is based on scientific evidence, supported by the medical literature, and derived from the clinical experiences of members of the OMA.

Methods

The scientific information and clinical guidance in this CPS is based upon referenced evidence and derived from the clinical perspectives of the authors.

Results

This OMA statement details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children. It provides clinical information regarding identifying and treating metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children over the 95th percentile of weight/height for age.

Conclusions

This OMA clinical practice statement details metabolic, behavioral health, and disordered eating comorbidities associated with obesity in children and provides an overview of current recommendations. These recommendations lay out a roadmap to the improvement of the health of children and adolescents with obesity, especially those with metabolic, physiological, and psychological complications.

Medications as a Trigger of Sleep-Related Eating Disorder: A Disproportionality Analysis

Sleep-related eating disorder (SRED) is a parasomnia with recurrent, involuntary, amnestic eating episodes during sleep. There is growing evidence of the association between SRED and medications. Therefore, we aimed to rank drugs showing the strongest association. VigiBase® (WHO pharmacovigilance database) was queried for all reports of “Sleep-related eating disorder”. Disproportionality analysis relied on the Reporting Odds Ratio, with its 95% Confidence Interval (CI), and the Information Component. Our VigiBase® query yielded 676 cases of drug-associated SRED. Reports mostly involved zolpidem (243, 35.9%), sodium oxybate (185, 27.4%), and quetiapine (97, 14.3%). Significant disproportionality was found for 35 medications, including zolpidem (387.6; 95%CI 331.2−453.7), sodium oxybate (204.2; 95%CI 172.4−241.8), suvorexant (67.3; 95%CI 38.0−119.2), quetiapine (53.3; 95%CI 43.0−66.1), and several psychostimulants and serotonin-norepinephrine reuptake inhibitors (SNRIs). Patients treated with nonbenzodiazepines or SNRIs were significantly older (mean age: 49.0 vs. 37.5; p < 0.001) and their SRED were more likely to be serious (62.6% vs. 51.4%; p = 0.014) than patients treated with sodium oxybate or psychostimulants. Psychotropic drugs are involved in almost all reports. In patients with SRED, an iatrogenic trigger should be searched for.

Diagnosing a nocturnal eating disorder in an average-weight man

A middle-aged man of average weight presented to the sleep medicine clinic for multiple episodes of nocturnal eating during night-time awakenings for the past several months. His symptoms were more characteristic of night eating syndrome rather than sleep-related eating disorder because of his recollection of the eating episodes and intake of edible substances during these episodes. He was treated with a low dose of sertraline with an initial improvement of symptoms followed by a relapse that was controlled with an increased dose. A year after initiation of therapy, his symptoms have resolved.

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.

Patterns of perceived parenting styles and associations with night eating syndrome symptoms and correlates among Chinese adolescents: a latent profile analysis

PURPOSE

This paper aimed to explore the association between the patterns of perceived parenting styles and adolescents' night eating syndrome symptoms and correlates, including sleep quality, weight status, loss of control over eating, and psychological distress.

METHODS

A sample of 455 Chinese adolescents (54.5% females, aged 12-15 years) were included in the current study. Latent Profile Analysis (LPA) was adopted to examine the patterns of perceived parenting styles. The three-step approach was used to explore the differences in night eating syndrome symptoms and correlates between different profiles.

RESULTS

A four-profile solution was found to fit the data best, and the four profiles were labeled as positive parenting, negative parenting, highly engaged parenting, and lowly engaged parenting. Subsequent analyses showed that adolescents across profiles exhibited significant differences in night eating syndrome symptoms and correlates. Specifically, adolescents in the positive parenting profile generally had the lowest scores in night eating and its correlates, while those in the negative parenting group reported the highest scores in night eating and its correlates.

CONCLUSION

Using a person-centered approach (i.e., LPA), the present study identified four distinct patterns of perceived parenting styles in a sample of Chinese adolescents, with night eating and related symptomatology differing across each profile. Future interventions targeting night eating among adolescents may consider the potential influence from the patterns of perceived parenting styles to have a better intervention outcome.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

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.

The nature of night eating syndrome: Using network analysis to understand unique symptomological relationships

OBJECTIVES

Despite the initial characterization of night eating syndrome (NES) in 1955, the definition and operationalization of its symptoms has varied considerably. To standardize the definition of NES and its symptoms, Allison et al. developed research diagnostic criteria. Even so, conceptualization and intervention of NES remains guided by medical models, which assume that pathology is driven by a distinct, underlying causal mechanism. Conversely, recent work on other eating disorders (EDs) has used network analysis to reconceptualize ED psychopathology and treatment by identifying (a) unique relationships between key symptoms, and (b) the symptoms most central to specific EDs. The present study examined NES symptoms through network analysis to identify the most central symptoms within the NES network.

METHOD

Regularized partial correlation networks were estimated using 144 individuals in a community sample diagnosed with NES. Participants completed semi-structured interviews, self-report measures, and food/sleep diaries to measure NES symptoms, nonspecific health domains (e.g., sleep disturbance, overall mood, stress, and circadian rhythm functioning), and transdiagnostic ED symptoms.

RESULTS

Depressed mood, poor sleep quality, and a strong urge to eat upon awakening at night were highly central to the psychopathology network for NES and were significantly more central than most other NES symptoms and nonspecific health domains.

DISCUSSION

This study provides insight on the unique symptomological relationships of NES and sets the stage for future work that can identify causal linkages among NES symptoms. These symptoms represent key elements of the core psychopathology of NES and should represent primary targets for intervention.

The Parasomnias

Parasomnias usually present in childhood and resolve spontaneously. The diagnosis of non-rapid eye movement-related parasomnias is mainly based on clinical descriptors and can be challenging. Rapid eye movement-related parasomnias may index an underlying psychiatric disorder. Even if benign, parasomnias can affect quality of life. Pediatricians and child psychiatrists should be familiarized with these sleep disorders and suggest adequate sleep hygiene, avoidance of sleep deprivation, and regular bedtimes even on weekends as the first step in management of these disorders. Clinicians should pursue the opportunity for tailoring treatments and consider referral to a sleep expert when indicated.

Adult NREM Parasomnias: An Update

Our understanding of non-rapid eye movement (NREM) parasomnias has improved considerably over the last two decades, with research that characterises and explores the causes of these disorders. However, our understanding is far from complete. The aim of this paper is to provide an updated review focusing on adult NREM parasomnias and highlighting new areas in NREM parasomnia research from the recent literature. We outline the prevalence, clinical characteristics, role of onset, pathophysiology, role of predisposing, priming and precipitating factors, diagnostic criteria, treatment options and medico-legal implications of adult NREM parasomnias.

Night eating model shows time-specific depression-like behavior in the forced swimming test

The circadian clock system is associated with feeding and mood. Patients with night eating syndrome (NES) delay their eating rhythm and their mood declines during the evening and night, manifesting as time-specific depression. Therefore, we hypothesized that the NES feeding pattern might cause time-specific depression. We established new NES model by restricted feeding with high-fat diet during the inactive period under normal-fat diet ad libitum. The FST (forced swimming test) immobility time in the NES model group was prolonged only after lights-on, corresponding to evening and early night for humans. We examined the effect of the NES feeding pattern on peripheral clocks using PER2::LUCIFERASE knock-in mice and an in vivo monitoring system. Caloric intake during the inactive period would shift the peripheral clock, and might be an important factor in causing the time-specific depression-like behavior. In the NES model group, synthesis of serotonin and norepinephrine were increased, but utilization and metabolism of these monoamines were decreased under stress. Desipramine shortened some mice’s FST immobility time in the NES model group. The present study suggests that the NES feeding pattern causes phase shift of peripheral clocks and malfunction of the monoamine system, which may contribute to the development of time-specific depression.

Pediatric Obesity Algorithm: A Practical Approach to Obesity Diagnosis and Management

Childhood obesity is a growing global health problem. Despite the highest rates of childhood obesity in the United States and other developed countries over the last 30 years, there is still no clear treatment strategy. Practitioners often do not know where to turn to find guidance on managing the nearly one third of their population who present for medical care either with obesity that coexists with other medical problems or because of obesity. The Pediatric Obesity Algorithm is an evidence based roadmap for the diagnosis and management of children with obesity. In this article, we summarize topics from the Pediatric Obesity Algorithm pertaining to pediatric obesity diagnosis, evaluation, and management including assessment, differential diagnosis, review of systems, diagnostic work up, physical exam, age specific management, comorbidities, use of medications and surgery, and medication associated weight gain. Identifying and treating children with obesity as early as possible is important, as is identifying comorbid conditions. Earlier and more comprehensive management through resources such as the Pediatric Obesity Algorithm serve to help guide health care practitioners with a practical and evidence based approach to the diagnosis and management of children with obesity, and provide families with the tools needed for a healthy future.

Disordered eating and obesity: associations between binge-eating disorder, night-eating syndrome, and weight-related comorbidities

Binge-eating disorder (BED) and night-eating syndrome (NES) are two forms of disordered eating associated with overweight and obesity. While these disorders also occur in nonobese persons, they seem to be associated with weight gain over time and higher risk of diabetes and other metabolic dysfunction. BED and NES are also associated with higher risk of psychopathology, including mood, anxiety, and sleep problems, than those of similar weight status without disordered eating. Treatments are available, including cognitive behavior therapy (CBT), interpersonal psychotherapy, lisdexamfetamine, and selective serotonin reuptake inhibitors (SSRIs) for BED; and CBT, SSRIs, progressive muscle relaxation, and bright light therapy for NES.

Night eating syndrome and its association with weight status, physical activity, eating habits, smoking status, and sleep patterns among college students

BACKGROUND

Night eating syndrome (NES) is characterized by evening hyperphagia and/or nocturnal ingestion.

OBJECTIVE

The main objective of this study was to assess the percentage of students complying with symptoms and behaviors consistent with the diagnostic criteria for NES, and explore its association with body mass index (BMI), dietary habits, physical activity, smoking status, and sleep patterns, among a sample of college students.

METHODS

A cross-sectional survey was conducted among a sample of 413 undergraduate students, mean age of 20.6 ± 1.68 SD, at Central Michigan University. Students completed an online survey including demographic information and the Night Eating Diagnostic Questionnaire (NEDQ) and Pittsburgh Sleep Quality Index Questionnaire (PSQI). Participants were grouped based on self-reporting of the presence and frequency of night eating-related symptoms and behaviors related to the diagnostic criteria for NES as follows: normal, mild night eater, moderate night eater, and full-syndrome night eater. Pearson's Chi-squared, Student's t test, and Wilcoxon rank-sum test were used to test the association between students with and without any night eating behavior in relation to BMI, lifestyle variables, and sleep duration/quality.

RESULTS

Results showed that the proportion of students complying with symptoms and behaviors consistent with full-syndrome of NES was 1.2%. There were no significant differences between students complying with symptoms and behaviors consistent with any level of NES and those without any night eating behavior regarding BMI, eating habits, physical activity, and smoking status. NES was significantly related to sleep duration (P = 0.023). Students complying with symptoms consistent with any level of NES reported shorter sleep time and had higher total PSQI score (6.73 ± 4.06) than students without the syndrome (5.61 ± 2.61) (P = 0.007).

CONCLUSION

Although the percentage of students complying with full-syndrome NES was relatively low in our student sample, those students had shorter sleep time and poorer sleep quality than the other groups. However, it is unclear whether evening hyperphagia is a response to a lack of sleep or vice versa, and further research is needed.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

The sleeping brain in Parkinson's disease: A focus on REM sleep behaviour disorder and related parasomnias for practicing neurologists

Sleep disorders are identified as common non-motor symptoms of Parkinson's disease (PD) and recently this recognition has been expanded to include parasomnias, encompassing not only REM sleep behaviour disorder (RBD), but also other non-REM forms. RBD, a prototypical parasomnia in PD, exists even in the prodromal stage of the disease, and is characterized by the presence of dream enactment behaviours occurring alongside a loss of normal skeletal muscle atonia during REM sleep. In contrast, non-REM parasomnias are more frequently observed in the late stage PD. However, the development of these disorders often overlaps and it is not uncommon for PD patients to meet the criteria for more than one type of parasomnias, thus making a clinical distinction challenging for practicing neurologists who are not sleep specialists. Indeed, clinical recognition of the predominant form of parasomnia does not just depend on video-polysomnography, but also on an individual physician's clinical acumen in delineating pertinent clinical history to determine the most likely diagnosis and proceed accordingly. In this review article, we highlight the various forms of parasomnias that have been reported in PD, including, but not limited to, RBD, with a focus on clinical symptomatology and implications for clinical practice. In addition, we review the differences in PD-related parasomnias compared to those seen in general populations. With advances in sleep research and better technology for ambulatory home monitoring, it is likely that many unanswered questions on PD-related parasomnias will soon be resolved resulting in better management of this nocturnal challenge in PD.

Matching Meals to Body Clocks-Impact on Weight and Glucose Metabolism

The prevalence of type 2 diabetes continues to rise worldwide and is reaching pandemic proportions. The notion that this is due to obesity, resulting from excessive energy consumption and reduced physical activity, is overly simplistic. Circadian de-synchrony, which occurs when physiological processes are at odds with timing imposed by internal clocks, also promotes obesity and impairs glucose tolerance in mouse models, and is a feature of modern human lifestyles. The purpose of this review is to highlight what is known about glucose metabolism in animal and human models of circadian de-synchrony and examine the evidence as to whether shifts in meal timing contribute to impairments in glucose metabolism, gut hormone secretion and the risk of type 2 diabetes. Lastly, we examine whether restricting food intake to discrete time periods, will prevent or reverse abnormalities in glucose metabolism with the view to improving metabolic health in shift workers and in those more generally at risk of chronic diseases such as type 2 diabetes and cardiovascular disease.

Is night eating syndrome associated with obstructive sleep apnea, BMI, and depressed mood in patients from a sleep laboratory study?

PURPOSE

The aim of this study was to assess night eating syndrome (NES) in patients referred for polysomnography and its association with obstructive sleep apnea (OSA). We also assessed whether participants with OSA were more likely to get up and eat at night, and whether these behaviors were associated with the apnea-hypopnea sleep index (AHI). We additionally examined whether NES and OSA were associated with BMI, and assessed depressed mood among participants with NES or OSA.

METHODS

The Night Eating Diagnostic Questionnaire (NEDQ), Zung Depression Scale, and demographic and medical questionnaires were used to evaluate 84 qualified participants. Polysomnography was used to assess AHI, and therefore OSA.

RESULTS

Thirty individuals met full or sub-threshold NES (NES[St]) criteria, and 54 had no night eating (Normal). Eighty-nine percent of the sample had OSA with AHI≥5. Neither AHI nor BMI differed between NES(St) and Normal, F(1,82)=1.67, p=0.20 and F(1, 82)=2.2, p=0.14, respectively. Participants with NES(St) were, however, more likely than Normal to have depressed mood (mild, moderately, or severely depressed), χ²=4.47 p=0.03. There was a positive correlation between AHI and BMI, r=0.37, p=0.001. Those with OSA were not more likely to eat at night, F(1,82)=0.04, p=0.84, or get out of bed more often, F(1,13)=0.23, p=0.64, and there was no correlation between AHI and eating at night (r=-0.11, p=0.31). However, there was a positive correlation between AHI and the number of times participants got up out of bed (r=0.81, p<0.001).

CONCLUSIONS

We found that NES was not associated with BMI or AHI severity. The findings show that NES is primarily an eating disorder, rather than a sleep disorder, and that there is an association between NES and depressed mood.

Comparison of clinical features between primary and drug-induced sleep-related eating disorder

PURPOSE

The aim of this study was to ascertain the clinical characteristics of drug-induced sleep-related eating disorder (SRED).

PATIENTS AND METHODS

We retrospectively reviewed the medical records of 30 patients with primary SRED (without any comorbid sleep disorders and who were not taking any possible causative medications), and ten patients with drug-induced SRED (occurrence of SRED episodes after starting nightly medication of sedative drugs, which completely resolved after dose reduction or discontinuation of the sedatives).

RESULTS

All patients with drug-induced SRED took multiple types of sedatives, such as benzodiazepines or benzodiazepine receptor agonists. Clinical features of drug-induced SRED compared with primary SRED were as follows: higher mean age of onset (40 years old in drug-induced SRED vs 26 years old in primary SRED), significantly higher rate of patients who had total amnesia during most of their SRED episodes (75.0% vs 31.8%), significantly lower rate of comorbidity of night eating syndrome (0% vs 63.3%), and significantly lower rate of history of sleepwalking (10.0% vs 46.7%). Increased doses of benzodiazepine receptor agonists may be responsible for drug-induced SRED.

CONCLUSION

The clinical features of drug-induced SRED were different from those of primary SRED, possibly reflecting differences in the underlying mechanisms between these two categories of SREDs.

[Psychometric Properties and Item Evaluation of Korean Version of Night Eating Questionnaire (KNEQ)]

PURPOSE

The aim of this study was to develop a Korean version of Night Eating Questionnaire (KNEQ) and test its psychometric properties and evaluate items according to item response theory.

METHODS

The 14-item NEQ as a measure of severity of the night eating syndrome was translated into Korean, and then this KNEQ was evaluated. A total of 1171 participants aged 20 to 50 completed the KNEQ on the Internet. To test reliability and validity, Cronbach's alpha, correlation, simple regression, and factor analysis were used. Each item was analyzed according to Rasch-Andrich rating scale model and item difficulty, discrimination, infit/outfit, and point measure correlation were evaluated.

RESULTS

Construct validity was evident. Cronbach's alpha was .78. The items of evening hyperphagia and nocturnal ingestion showed high ability in discriminating people with night eating syndrome, while items of morning anorexia and mood/sleep provided relatively little information. The results of item analysis showed that item2 and item7 needed to be revised to improve the reliability of KNEQ.

CONCLUSION

KNEQ is an appropriate instrument to measure severity of night eating syndrome with good validity and reliability. However, further studies are needed to find cut-off scores to screen persons with night eating syndrome.

Annual Research Review: Sleep problems in childhood psychiatric disorders--a review of the latest science

BACKGROUND

Hippocrates flagged the value of sleep for good health. Nonetheless, historically, researchers with an interest in developmental psychopathology have largely ignored a possible role for atypical sleep. Recently, however, there has been a surge of interest in this area, perhaps reflecting increased evidence that disturbed or insufficient sleep can result in poor functioning in numerous domains. This review outlines what is known about sleep in the psychiatric diagnoses most relevant to children and for which associations with sleep are beginning to be understood. While based on a comprehensive survey of the literature, the focus of the current review is on the latest science (largely from 2010). There is a description of both concurrent and longitudinal links as well as possible mechanisms underlying associations. Preliminary treatment research is also considered which suggests that treating sleep difficulties may result in improvements in behavioural areas beyond sleep quality.

FINDINGS

To maximise progress in this field, there now needs to be: (a) greater attention to the assessment of sleep in children; (b) sleep research on a wider range of psychiatric disorders; (c) a greater focus on and examination of mechanisms underlying associations; (d) a clearer consideration of developmental questions and (e) large-scale well-designed treatment studies.

CONCLUSIONS

While sleep problems may sometimes be missed by parents and healthcare providers; hence constituting a hidden risk for other psychopathologies - knowing about these difficulties creates unique opportunities. The current excitement in this field from experts in diverse areas including developmental psychology, clinical psychology, genetics and neuropsychology should make these opportunities a reality.

Treatment of sleep-related eating disorder

OPINION STATEMENT

Sleep-related eating disorder (SRED) is classified as an NREM-related parasomnia characterized by recurrent episodes of dysfunctional eating that occur after an arousal from the main sleep period with partial or complete amnesia for the event, resulting in weight gain from eating high calorie foods and causing various injuries due to consumption of inedible or toxic items. SRED can be idiopathic or commonly associated with other primary sleep disorders such as sleepwalking, restless legs syndrome (RLS), obstructive sleep apnea syndrome (OSAS), other clinical conditions, or use of sedative-hypnotic medications. First-line treatment of idiopathic SRED includes selective serotonin reuptake inhibitors (SSRIs) at mean dosages of 20 to 30 mg/day. Topiramate at 100-300 mg/day and clonazepam at 0.5-2.0 mg/day can be valid alternative options. SRED related to other parasomnias or sleep disturbances that cause sleep fragmentation benefit most from treatment of the associated sleep disorder. In particular, RLS-related SRED is best treated with dopamine agonists such as pramipexole, while sleepwalking-related SRED benefits from low-dose benzodiazepines such as clonazepam. Different kinds of drug associations have been proposed in a limited number of cases, especially in the past. We strongly recommend that all patients suffering from SRED should undergo consistent and regular follow-up about 2-3 times per year or otherwise according to the physician's judgment, in order to assess the evolution of symptom severity and frequency and re-evaluate treatment efficacy and any side effects that may arise.

Sleep-related eating disorder and its associated conditions

Sleep-related eating disorder (SRED) is a condition characterized by recurrent episodes of eating at the transition from night-time sleep to arousal. SRED patients describe eating in an out-of-control manner with preference for high-caloric foods and sometimes with inedible or toxic items. Level of consciousness during SRED episodes ranges from partial consciousness to dense unawareness typical of somnambulistic episodes. SRED is sometimes associated with psychotropic medication, in particular sedative hypnotics, and other sleep disorders, including parasomnias, narcolepsy, and restless legs syndrome. Night eating syndrome (NES) is another important condition in the disordered night-time eating spectrum showing hyperphagia episodes at full arousal from nocturnal sleep without accompanying amnesia. NES could be considered an abnormality in the circadian rhythm of meal timing with a normal circadian timing of sleep onset. The two conditions often overlap and possibly share a common pathophysiology. Studies have suggested that central nervous system serotonin modulation may lead to an effective treatment of NES, while the anti-seizure medication topiramate may be an effective SRED treatment.

Manipulating the circadian and sleep cycles to protect against metabolic disease

Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock, and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g., obesity) involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude-enhancing small molecules (CEMs) identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep, and metabolism will also have far-reaching implications for various chronic human diseases and aging.

Non-Benzodiazepine Receptor Agonists for Insomnia

Because of proven efficacy, reduced side effects, and less concern about addiction, non-benzodiazepine receptor agonists (non-BzRA) have become the most commonly prescribed hypnotic agents to treat onset and maintenance insomnia. First-line treatment is cognitive-behavioral therapy. When pharmacologic treatment is indicated, non-BzRA are first-line agents for the short-term and long-term management of transient and chronic insomnia related to adjustment, psychophysiologic, primary, and secondary causation. In this article, the benefits and risks of non-BzRA are reviewed, and the selection of a hypnotic agent is defined, based on efficacy, pharmacologic profile, and adverse events.

Restless Eating, Restless Legs, and Sleep Related Eating Disorder

Restless legs syndrome (RLS) often presents with a primary complaint of sleep initiation difficulty with only ambiguous allusions to motor symptoms. This may result in the condition being misdiagnosed as a psychophysiological insomnia. Further, nocturnal eating is common in RLS and like the classic motor symptoms, patients will describe an inability to initiate sleep until their urge (to eat) is addressed. Restless nocturnal eating arises, intensifies, and subsides in parallel to motor symptoms. Once misdiagnosed as psychophysiological insomnia, RLS patients are frequently treated with benzodiazepine receptor agonists. The CNS actions of these sedating agents, suppression of memory and executive function, unleash predisposed amnestic behaviors. In the case of RLS this would be expected to include the inappropriate ambulatory and eating behaviors of sleep related eating disorder (SRED). The evidence and implications of a link between the restless eating of RLS and SRED is presented here.

Nutritional Aspects of Late Eating and Night Eating

The timing of food intake has been investigated as a novel factor in the etiology, maintenance, and treatment of obesity. Indeed, consuming a large proportion of food later in the day and into the night has been associated with higher body weight and may even impair weight loss. The diet quality of late-eaters may be a factor involved in these relationships. Moreover, the nutritional characteristics of the foods consumed during the night may negatively affect metabolic and circadian rhythms that are required for optimal health. This review will first examine the diet quality of late-eaters and describe common foods consumed as nocturnal snacks. Second, this review will briefly acknowledge the potential adverse metabolic and circadian effects of consuming certain foods very late in the evening or during the night.

Sleep-related eating disorder: a descriptive study in Chilean patients

OBJECTIVES

We aimed to describe a group of adults diagnosed with sleep-related eating disorder (SRED) at the Sleep Medicine Center of the Pontificia Universidad Catolica de Chile.

METHODS

We performed a descriptive study of 34 consecutive patients who met the criteria of the International Classification of Sleep Disorders for SRED evaluated during a 3-year period who did not have an eating disorder according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. All patients had a structured clinical interview performed by a sleep specialist and completed the Beck Depression Inventory (BDI). Polysomnography (PSG) was performed when clinically indicated for ruling out other sleep-related disorders (18 patients; 52.9%). Patients' demographic and clinical data, comorbidities, and treatment response also were analyzed.

RESULTS

Most patients were women (n=23; 67.6%). The average age at the time of diagnosis was 39±13.8 (17-67 years) and the latency since symptom onset was 8.3±8.8 years. Most patients had several episodes per night (average, 2.6±1.6; 1-8) and all except one patient had partial or total amnesia of these events (n=33; 97%). Comorbidities were frequent and included insomnia (n=20; 58.8%), restless legs syndrome (RLS) (n=16; 47%), sleep-disordered breathing (SDB) (n=9; 26%), psychiatric disorders (n=13; 38.2%), and overweight or obesity (n=14; 41.1%). Most patients were hypnotic users (n=21; 61.7%) and reported weight-centered anxiety (n=23; 67.6%). Twenty patients (58.8%) were treated with topiramate, 17 of whom had adequate symptomatic responses.

CONCLUSION

Our SRED patients showed female preponderance, amnesia during the episodes, association with other sleep disorders, use of hypnotics, weight-centered anxiety, and positive response to topiramate. The presence of anxiety focused on weight in most patients may be an important element in the emergence of this behavior during sleep.

Novel putative mechanisms to link circadian clocks to healthy aging

The circadian clock coordinates the internal physiology to increase the homeostatic capacity thereby providing both a survival advantage to the system and an optimization of energy budgeting. Multiple-oscillator circadian mechanisms are likely to play a role in regulating human health and may contribute to the aging process. Our aim is to give an overview of how the central clock in the hypothalamus and peripheral clocks relate to aging and metabolic disorders, including hyperlipidemia and hyperglycemia. In particular, we unravel novel putative mechanisms to link circadian clocks to healthy aging. This review may lead to the design of large-scale interventions to help people stay healthy as they age by adjusting daily activities, such as feeding behavior, and or adaptation to age-related changes in individual circadian rhythms.

Short neuropeptide F is a sleep-promoting inhibitory modulator

To advance the understanding of sleep regulation, we screened for sleep-promoting cells and identified neurons expressing neuropeptide Y-like short neuropeptide F (sNPF). Sleep induction by sNPF meets all relevant criteria. Rebound sleep following sleep deprivation is reduced by activation of sNPF neurons, and flies experience negative sleep rebound upon cessation of sNPF neuronal stimulation, indicating that sNPF provides an important signal to the sleep homeostat. Only a subset of sNPF-expressing neurons, which includes the small ventrolateral clock neurons, is sleep promoting. Their release of sNPF increases sleep consolidation in part by suppressing the activity of wake-promoting large ventrolateral clock neurons, and suppression of neuronal firing may be the general response to sNPF receptor activation. sNPF acutely increases sleep without altering feeding behavior, which it affects only on a much longer time scale. The profound effect of sNPF on sleep indicates that it is an important sleep-promoting molecule.

Somnambulism: clinical aspects and pathophysiological hypotheses

Somnambulism, or sleepwalking, can give rise to a wide range of adverse consequences and is one of the leading causes of sleep-related injury. Accurate diagnosis is crucial for proper management and imperative in an ever-increasing number of medicolegal cases implicating sleep-related violence. Unfortunately, several widely held views of sleepwalking are characterised by key misconceptions, and some established diagnostic criteria are inconsistent with research findings. The traditional idea of somnambulism as a disorder of arousal might be too restrictive and a comprehensive view should include the idea of simultaneous interplay between states of sleep and wakefulness. Abnormal sleep physiology, state dissociation, and genetic factors might explain the pathophysiology of the disorder.

Disordered eating behaviors and sleep disturbances

The aim of the present study was to investigate if disordered eating behaviors predicted the development of sleep disturbances. A total of 870 students participated at baseline, 592 one year later (T1) and 305 two years later (T2). The Eating Attitudes Test-40 was used to assess global disordered eating behaviors, dietary concerns (DC), bulimic behaviors (BB) and social pressure to eat (SPE). Sleep disturbances were assessed by two items related to difficulties initiating sleep (DIS) and maintaining sleep (DMS). A sleep disturbance index (SDI) was calculated by summing DIS and DMS scores. Results revealed that global disordered eating behaviors at baseline predicted DIS, DMS and SDI at T1 and T2. Students with increased BB and SPE scores at baseline were more likely to experience sleep onset and sleep maintenance difficulties in the long term. These results suggest that assessment and correction of eating behaviors might prevent sleep disturbances.

Prevalence and clinical characteristics of unremembered nocturnal eating in diabetic subjects: Kurume sleep trouble in obesity and metabolic disorders (KUSTOMED) study

Nighttime food intake is associated with weight gain and higher HbA1c levels. We experienced night eaters who have no memory of their nocturnal eating in the morning. In this study, the curious night eating behavior was designated as "unremembered nocturnal eating syndrome (UNES)". We screened 1,169 patients with diabetes for sleep quality and abnormal eating behavior at night using the Pittsburgh Sleep Quality Index questionnaire with an additional question regarding UNES. When abnormal nocturnal eating behavior was noted, detailed clinical information was extracted from interviews with the patients. We identified 9 patients who experienced UNES. They had a higher BMI compared with subjects who reported no such episodes. Among them, 6 patients who consumed food at night without memory 2-5 times per month or more had significantly higher HbA1c levels. Continuous glucose monitoring in a patient with type 1 diabetes revealed an abrupt elevation of glucose levels from midnight when some foods were consumed. Eight of the 9 patients were taking benzodiazepine and/or non-benzodiazepine hypnotic agents when they experienced the episodes. The prevalence of UNES was 0.8% in all subjects and 4% in those taking hypnotic drugs. The ratio of hypnotic drug use in subjects with UNES was significantly higher than for individuals without UNES (89% vs. 17%, p<0.0001). Although UNES seems to be etiologically heterogeneous, hypnotics-induced parasomnia and/or anterograde amnesia may be associated with the behavior. UNES is not rare in diabetic patients on hypnotic medicine and may be a hidden cause of unexpected morning hyperglycemia.

Night eating syndrome in young adults: delineation from other eating disorders and clinical significance

The Night Eating Syndrome (NES) is a recently described disordered eating style whose status in current diagnostic systems needs to be further clarified. The aim of this study was to increase knowledge about the clinical features of NES in a sample of 1514 young adults aged 18-26 years from the general population who participated in an anonymous Internet survey. We first examined characteristics of NES and tried to delineate it from healthy controls as well as from other eating disorders in terms of socio-demography, eating disorder pathology and general psychopathology. Second, we attempted to further clarify the clinical utility of the NES by assessing the degree of distress as well as impairment. Twenty (1.3%) participants with NES were identified and there was only modest overlap between NES and both Binge Eating Disorder (BED) and Bulimia nervosa (BN) according to questionnaire-based DSM-IV criteria. Compared to healthy controls, NES individuals reported more pronounced eating disorder pathology as well as general psychopathology (depressive symptoms, chronic social stress). NES seems to be associated with considerable distress and impairment. Implications for the validity and classification of NES are discussed.

Parasomnias: an updated review

Parasomnias are abnormal behaviors emanating from or associated with sleep. Sleepwalking and related disorders result from an incomplete dissociation of wakefulness from nonrapid eye movement (NREM) sleep. Conditions that provoke repeated cortical arousals, 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 an arousal from sleep. SRED is often associated with the use of sedative-hypnotic medications; in particular, the widely prescribed benzodiazepine receptor agonists. Recently, compelling evidence suggests that nocturnal eating may in some cases be a nonmotor manifestation of Restless Legs Syndrome (RLS). rapid eye movement (REM) Sleep Behavior Disorder (RBD) is characterized by a loss of REM paralysis leading to potentially injurious dream enactment. The loss of atonia in RBD often predates the development of Parkinson's disease and other disorders of synuclein pathology. Parasomnia behaviors are related to an activation (in NREM parasomnias) or a disinhibition (in RBD) of central pattern generators (CPGs). Initial management should focus on decreasing the potential for sleep-related injury followed by treating comorbid sleep disorders. Clonazepam and melatonin appear to be effective therapies in RBD, whereas paroxetine has been reported effective in some cases of sleep terrors. At this point, pharmacotherapy for other parasomnias is less certain, and further investigations are necessary.

Restless nocturnal eating: a common feature of Willis-Ekbom Syndrome (RLS)

STUDY OBJECTIVES

To determine the frequency of nocturnal eating (NE) and sleep related eating disorder (SRED) in restless legs syndrome (RLS) versus psychophysiological insomnia (INS), and the relationship of these conditions with dopaminergic and sedative-hypnotic medications.

DESIGN

Prospective case series.

SETTING

Sleep disorders center.

PATIENTS

Newly diagnosed RLS or INS.

INTERVENTION

RLS or INS pharmacotherapy with systematic follow up interview for NE/SRED.

MEASUREMENTS AND RESULTS

Patients presenting with RLS (n = 88) or INS (n = 42) were queried for the presence of NE and SRED. RLS patients described nocturnal eating (61%) and SRED (36%) more frequently than INS patients (12% and 0%; both p < 0.0001). These findings were not due to arousal frequency, as INS patients were more likely to have prolonged nightly awakenings (93%) than RLS patients (64%; p = 0.003). Among patients on sedative-hypnotics, amnestic SRED and sleepwalking were more common in the setting of RLS (80%) than INS (8%; p < 0.0001). Further, NE and SRED in RLS were not secondary to dopaminergic therapy, as RLS patients demonstrated a substantial drop (68% to 34%; p = 0.0026) in the frequency of NE after dopamine agents were initiated, and there were no cases of dopaminergic agents inducing novel NE or SRED.

CONCLUSION

NE is common in RLS and not due to frequent nocturnal awakenings or dopaminergic agents. Amnestic SRED occurs predominantly in the setting of RLS mistreatment with sedating agents. In light of previous reports, these findings suggest that nocturnal eating is a non-motor manifestation of RLS with several clinical implications discussed here.

Sleep-related eating disorder versus sleepwalking: a controlled study

BACKGROUND/OBJECTIVE

Sleep-related eating disorder (SRED) may have some common clinical features with sleepwalking and with eating behavior disorders. The objective of this study was to compare clinical, sleep, and eating behavior measures in patients with SRED vs. sleepwalkers and controls.

METHODS

Overall, 15 patients with SRED, 21 sleepwalkers, and 20 age- and sex-matched healthy volunteers underwent interviews, completed sleep, anxiety, depression, and eating behavior scales, and had a night-time videopolysomnography.

RESULTS

Patients with SRED were mainly women, had disease onset in adulthood, suffered nightly episodes and insomnia, and had more frequent eating problems in childhood and higher current anorexia scores than sleepwalkers and controls. Unlike controls, they shared several commonalities with sleepwalkers, including a high frequency (66%) of past or current sleepwalking, a similar timing of parasomnia episodes during the first half of the night, numerous arousals from stage N3, and a similarly altered level of daytime sleepiness and anxiety, but higher awareness during parasomnia episodes. Conversely, only 10% of sleepwalkers ate during their sleepwalking episodes. On videopolysomnography, the eating episodes occurred mostly within 1min after awakening from stage N2 (n=9) or stage N3 (n=6). The frequencies of restless legs syndrome, periodic leg movements, and sleep apnea were similar across the three groups.

CONCLUSIONS

Patients with SRED share several clinical commonalities with sleepwalkers (although their level of awareness is higher) plus former or current eating behavior problems. It suggests that they have specialized a former sleepwalking behavior toward sleep-related eating because they are more vulnerable to eating behavior problems during the daytime.

Familial circadian rhythm disorder in the diurnal primate, Macaca mulatta

In view of the inverse temporal relationship of central clock activity to physiological or behavioral outputs in diurnal and nocturnal species, understanding the mechanisms and physiological consequences of circadian disorders in humans would benefit from studies in a diurnal animal model, phylogenetically close to humans. Here we report the discovery of the first intrinsic circadian disorder in a family of diurnal non-human primates, the rhesus monkey. The disorder is characterized by a combination of delayed sleep phase, relative to light-dark cycle, mutual desynchrony of intrinsic rhythms of activity, food intake and cognitive performance, enhanced nighttime feeding or, in the extreme case, intrinsic asynchrony. The phenotype is associated with normal length of intrinsic circadian period and requires an intact central clock, as demonstrated by an SCN lesion. Entrainment to different photoperiods or melatonin administration does not eliminate internal desynchrony, though melatonin can temporarily reinstate intrinsic activity rhythms in the animal with intrinsic asynchrony. Entrainment to restricted feeding is highly effective in animals with intrinsic or SCN lesion-induced asynchrony. The large isolated family of rhesus macaques harboring the disorder provides a powerful new tool for translational research of regulatory circuits underlying circadian disorders and their effective treatment.