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

Current evidence and future perspectives in the exploration of sleep-related eating disorder-a systematic literature review

Sleep-related eating disorder (SRED) is a non-REM parasomnia with potentially significant negative effects on general health (dangerous activities during night eating episodes, obesity, or metabolic syndrome, for example). Although the history of SRED encompasses more than six decades, public awareness and even the awareness of the mental health specialists of this disorder is very limited, a phenomenon that hinders the development of research in this field. Therefore, a systematic review based on PRISMA 2020 guidelines explored the available evidence for SRED found in four electronic databases (PubMed, Cochrane Collaboration, Google Scholar, and Clarivate/Web of Science). A number of 94 primary and secondary reports were retrieved, investigating aspects regarding the risk factors, epidemiology, clinical data and differential diagnosis, epidemiology, structured evaluation, and treatment of SRED. Based on the results of these reports, Z-drugs, but also certain benzodiazepines, antidepressants, antipsychotics, and psychostimulants may trigger the onset of SRED. Psychiatric and neurologic disorders have also been associated with SRED, either as risk factors or comorbid conditions. Cerebral glucose metabolism dysfunctions, neurotransmitter dysfunctions, and genetic factors have been invoked as pathogenetic contributors. Structured assessment of SRED is possible, but there is a dearth of instruments dedicated to this purpose. Data on the prevalence and treatment of SRED exist, but good-quality epidemiological studies and clinical trials are still missing. In conclusion, future research is expected to address the shortcomings of SRED exploration by creating the conditions for better quality and larger group clinical research. The need for such investigation is granted by the importance of this pathology and its negative functional consequences.

Polysomnography findings in sleep-related eating disorder: a systematic review and case report

Background

Sleep-related eating disorder (SRED) consists of recurrent episodes of uncontrolled, involuntary eating and drinking 1-3 h after falling asleep with partial or full unconsciousness. This condition is diagnosed based on interviews with the patients affected and the diagnostic criteria of the International Classification of Sleep Disorders. However, polysomnography (PSG) is not necessary to confirm this disease. This systematic review aims to evaluate the findings of PSG in SRED patients.

Methods

For this systematic review, PubMed, Embase, and Scopus databases were searched in February 2023, which resulted in 219 records. After removing duplicates, the articles that included the presentation of PSG results of SRED patients in English were selected. In addition, only original studies were considered. The risk of bias by using case reports and descriptive studies was assessed using the Joanna Briggs Institute critical appraisal tools and the Risk of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool. Furthermore, a case report of a 66-year-old woman with SRED was included.

Results

A total of 15 papers were selected for further analysis, of which 7 were descriptive studies, 6 were case reports, and 2 were observational studies. The risk of bias in the majority of the studies was moderate or high. Unexpectedly, if the eating episode occurred during PSG, in most cases it was not observed during deep sleep (the N3 sleep stage). Moreover, studies did not report significant deviations in the sleep parameters measured using PSG. Among SRED patients, the prevalence of sleepwalking was much higher than the general population. Our case report presented a potentially life-threatening episode of holding an apple in the mouth that might result in choking, which was captured using PSG.

Conclusion

Polysomnography is not necessary for the diagnosis of SRED. However, it could facilitate the diagnosis and differentiation of SRED from other eating disorders. PSG also has limitations in capturing eating episodes and in addition, its cost effectiveness should be considered during the diagnostic process. More studies into the pathophysiology of SRED are needed because classifying SRED as non-rapid eye movement parasomnias can be inappropriate as it does not always occur during deep sleep.

Drugs Used in Parasomnia

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

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.

Drugs Used in Parasomnia

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

Topiramate reduces nocturnal eating in sleep-related eating disorder

Study Objectives

Sleep-related eating disorder (SRED) is a parasomnia characterized by partial arousals from sleep with compulsive consumption of food with impaired level of awareness and memory for the event. Small case series’ have demonstrated efficacy of topiramate in SRED. We conducted a placebo-controlled randomized clinical trial of topiramate to assess efficacy in SRED.

Methods

Thirty-four participants with an ICSD-2/ICSD-3 diagnosis of SRED with >6 months of symptoms and ≥3 sleep-related eating episodes per week were randomized to placebo or topiramate with flexible dosing to a maximum dosage of 300 mg for 13 weeks. Primary outcomes were percentage of nights with eating and Clinician Global Impression-Improvement (CGI-I). Intention-to-treat last observation carried forward (ITT LOCF) analysis was conducted.

Results

Mean age was 39.5 years, 74% were female, with mean duration of sleep-related eating of 13.7 years. SRED symptoms were significantly reduced with topiramate (74.7% to 33.2% nights/week; n = 15) compared to placebo (77.0% to 57.4%; n = 17) (p = 0.035). There were significantly more CGI-I responders on topiramate (71%) than placebo (27%) (p = 0.016). Level of wakefulness (r = −0.49) and memory for nighttime eating (r = −0.58) at baseline predicted topiramate response. The topiramate group lost significantly more weight than the placebo group (−8.5 lbs vs. +1.0 lbs, p = 0.001). The most common side effects were paresthesias and cognitive dysfunction.

Conclusions

This first randomized controlled trial demonstrating efficacy for treatment of SRED supports preliminary data on the use of topiramate for SRED. Side effects were prominent for topiramate. Limitations include a small sample size and a high drop-out rate in both study groups.

Clinical Trial Information

NCT00606411

Non-REM Parasomnia: The Promise of Precision Medicine

Our understanding of non-REM parasomnias is just beginning to unfold the potential biomarkers and underlying pathophysiologic processes that lead to these events. Biomarkers need further investigation and will help us to understand better ways to develop risk models and possible mechanisms. Similarly, as we develop more accurate pathophysiologic-based diagnostic testing for non-REM parasomnias, we will begin the evolution toward a physiologic-based classification scheme that aids the application of precision medicine. This article explores currently known characteristics and exploratory features that may aid in this transition to better understanding our individual patients with non-REM parasomnias and tailoring their treatments.

Prevalence of Parasomnias in Patients With Obstructive Sleep Apnea. A Registry-Based Cross-Sectional Study

Objective: To assess the prevalence of parasomnias in relation to presence and severity of obstructive sleep apnea (OSA). We hypothesized higher parasomnia prevalence with higher OSA severity.

Methods: The sample comprised 4,372 patients referred to a Norwegian university hospital with suspicion of OSA (mean age 49.1 years, 69.8% males). OSA was diagnosed and categorized by standard respiratory polygraphy (type 3 portable monitor). The patients completed a comprehensive questionnaire prior to the sleep study, including questions about different parasomnias during the last 3 months. Pearson chi-square tests explored differences according to the presence and severity of OSA. Furthermore, logistic regression analyses with the parasomnias as dependent variables and OSA severity as predictor were conducted (adjusted for sex, age, marital status, smoking, and alcohol consumption).

Results: In all, 34.7% had apnea-hypopnea index (AHI) <5 (no OSA), 32.5% had AHI 5-14.9 (mild OSA), 17.4% had AHI 15-29.9 (moderate OSA), and 15.3% had AHI ≥30 (severe OSA). The overall prevalence of parasomnias was 3.3% (sleepwalking), 2.5% (sleep-related violence), 3.1% (sexual acts during sleep), 1.7% (sleep-related eating), and 43.8% (nightmares). The overall parasomnia prevalence was highest in the no OSA group. In the chi-square analyses, including all OSA groups, the prevalence of sleep-related violence and nightmares were inversely associated with OSA severity, whereas none of the other parasomnias were significantly associated with OSA severity. In adjusted logistic regression analyses the odds of sleepwalking was significantly higher in severe compared to mild OSA (OR = 2.0, 95% CI = 1.12–3.55). The other parasomnias, including sleep-related violence and nightmares, were not associated with OSA presence or severity when adjusting for sex and age.

Conclusions: We found no increase in parasomnias in patients with OSA compared to those not having OSA. With the exception of sleepwalking, the parasomnias were not associated with OSA severity.

Psychiatric Illness and Parasomnias: a Systematic Review

PURPOSE OF REVIEW

Little is known about the presence of parasomnias such as nightmare disorder, sleep paralysis, REM sleep behavior disorder (RBD), and sleep-related eating disorders (SRED) in people with mental illness. A predominant view suggests that psychotropic medications might be contributing to parasomnias. This article summarizes knowledge regarding the relationships between psychiatric disorders and parasomnias, and possible confounds. A systematic search of the literature in the past 10 years identified 19 articles.

RECENT FINDINGS

There were significantly elevated rates of parasomnias in psychiatric disorders (average prevalence of nightmares was 38.9%, sleep paralysis 22.3%, SRED 9.9%, sleepwalking 8.5%, and RBD 3.8%). Medication usage was only one of many risk factors (other sleep disorders, medical comorbidities, and substance abuse) which were associated with parasomnias. A strong association exists between mental illness and parasomnias which is not fully explained by medications. Prospective longitudinal studies are needed to develop a better understanding of the unique and shared variance from multiple risk factors.

Zolpidem Induced Sleep-related Eating and Complex Behaviors in a Patient with Obstructive Sleep Apnea and Restless Legs Syndrome

Zolpidem-induced sleep-related complex behaviors (SRCB) with anterograde amnesia have been reported. We describe herein a case in which the development of zolpidem-induced sleep-related eating disorder (SRED) and SRCB was strongly suspected. A 71-year-old Korean male was admitted to the Department of Psychiatry due to his repetitive SRED and SRCB with anterograde amnesia, which he reported as having occurred since taking zolpidem. The patient also had restless legs syndrome (RLS) and obstructive sleep apnea (OSA). His baseline serum iron level was low at admission. Zolpidem discontinuation resulted in the immediate disappearance of his SRED, but did not affect his RLS symptoms. These symptoms rapidly improved after adding a single i.v. iron injection once daily, and so he was discharged to day-clinic treatment. These findings indicate that zolpidem can induce SRCB. Although the pathophysiology of zolpidem-induced SRED and other SRCB remains unclear, clinicians should carefully monitor for the potential induction of complex behaviors associated with zolpidem in patients with comorbid RLS or OSA.

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.