The case for investigating a bidirectional association between insomnia symptoms and eating disorder pathology

The Integration of Sleep Research Into Eating Disorders Research: Recommendations and Best Practices

OBJECTIVE

Sleep disturbance is common among individuals with eating disorders (EDs), with approximately 50% of patients with EDs reporting sleep disturbance. Sleep problems may promote, exacerbate, or maintain ED symptoms through a variety of hypothesized mechanisms, such as impaired executive function, increased negative affect, and disruptions to appetitive rhythms. Although research investigating the role of sleep in EDs is growing, the current literature suffers from methodological limitations and inconsistencies, which reduce our ability to translate findings to improve clinical practice. The purpose of this forum is to propose a coordinated approach to more seamlessly integrate sleep research into ED research with particular emphasis on best practices in the definition and assessment of sleep characteristics.

METHODS

In this article, we will describe the current status of sleep-related research and relevant gaps within ED research practices, define key sleep characteristics, and review common assessment strategies for these sleep characteristics. Throughout the forum, we also discuss study design considerations and recommendations for future research aiming to integrate sleep research into ED research.

RESULTS/DISCUSSION

Given the potential role of sleep in ED maintenance and treatment, it is important to build upon preliminary findings using a rigorous and systematic approach. Moving forward as a field necessitates a common lens through which future research on sleep and EDs may be conducted, communicated, and evaluated.

Engagement in binge eating and fasting associated with poorer sleep quality in an online sample of adults

OBJECTIVES

Both disordered eating and disturbed sleep represent significant threats to mental health. Accumulating evidence suggests that disordered eating behaviors and sleep problems co-occur. A majority of current research, however, has focused on these behaviors as components of eating disorder diagnoses, rather than investigating the independent associations of transdiagnostic disordered eating behaviors and sleep. The present study sought to examine fasting, binge eating, self-induced vomiting, laxative or diuretic misuse, and driven exercise as predictors of sleep quality complaints.

METHOD

An online sample of 648 U.S. adults completed the Eating Disorder Examination - Questionnaire, the Pittsburgh Sleep Quality Index, and the Patient Health Care Questionnaire-2 as part of a larger parent study.

RESULTS

Results of a hierarchical linear regression revealed that, collectively, disordered eating behaviors predicted worse sleep quality [R2 = 0.30, F(7, 640) = 31.21, p < .001], and that both binge eating and fasting, but not other compensatory behaviors, accounted for unique variance in sleep quality after controlling for BMI and depression.

CONCLUSIONS

Overall, findings suggest that transdiagnostic disordered eating behaviors are associated with sleep quality complaints. Improved understanding of the specific relationships between individual eating behaviors and sleep characteristics can help refine the identification of individuals at high risk for sleep disturbance and address the potential reciprocal influence of sleep quality on disordered eating behaviors.

Impact of sleep disruption on BDD symptoms and treatment response

BACKGROUND

Body dysmorphic disorder (BDD) is severe, undertreated, and relatively common. Although gold-standard cognitive behavioral therapy (CBT) for BDD has strong empirical support, a significant number of patients do not respond. More work is needed to understand BDD's etiology and modifiable barriers to treatment response. Given its high prevalence and impact on the development, maintenance, and treatment of related, frequently comorbid disorders, sleep disruption is a compelling, but not-yet studied factor.

METHODS

Data were drawn from a randomized controlled trial of guided smartphone app-based CBT for BDD. Included participants were offered 12-weeks of treatment, immediately (n = 40) or after a 12-week waitlist (n = 37). Sleep disruption and BDD symptom severity were assessed at baseline, week-6, and week-12.

RESULTS

Hypotheses and analysis plan were pre-registered. Two-thirds of patients reported significant insomnia symptoms at baseline. Baseline severity of sleep disruption and BDD symptoms were not related (r = 0.02). Pre-treatment sleep disruption did not predict BDD symptom reduction across treatment, nor did early sleep improvements predict greater BDD symptom improvement. Early BDD symptom improvement also did not predict later improvements in sleep.

LIMITATIONS

Limitations include the small sample, restricted ranges of BDD symptom severity and treatment response, and few metrics of sleep disruption.

CONCLUSIONS

Although insomnia was disproportionately high in this sample and both BDD symptoms and sleep improved in treatment, results suggest sleep and BDD symptoms may function largely independent of one another. More work is encouraged to replicate and better understand findings as well as potential challenges and benefits of addressing sleep in BDD.

Weight bias internalization is positively associated with insomnia symptom severity in young women with disordered eating

OBJECTIVE

Social stigma has been associated with disparities in sleep heath; however, one type of stigma that has been less evaluated is weight bias internalization. Previous studies have shown inconsistent results linking weight bias internalization and sleep problems and few have examined associations with insomnia.

METHODS

Women with disordered eating (N = 173, Mage=20.22, SD=1.70, range=18-25) completed questionnaires measuring insomnia symptoms, weight bias internalization, alcohol use, and dysphoria. Linear regression tested associations between weight bias internalization and insomnia symptom severity, after adjusting for demographic variables, alcohol use, and dysphoria.

RESULTS

Weight bias internalization, alcohol use, and dysphoria were significantly positively associated with insomnia symptom severity above-and-beyond demographic variables.

CONCLUSIONS

Although effect sizes were small, weight bias internalization was associated with greater insomnia symptom severity. Results add to the growing literature examining the associations of stigma with sleep health.

Preliminary study: cognitive behavioural therapy for insomnia in adolescents with anorexia nervosa

PURPOSE

Insomnia and anorexia nervosa (AN) are frequently comorbid, negatively affecting the evolution and the prognosis of AN. Within this framework, the management of sleep disorders appears as critical. The aim of this retrospective study is to assess, for the first time, the efficacy of cognitive and behavioural therapy for insomnia (CBT-I) on sleep disturbances in adolescents with AN. To do so, we investigated the impact of CBT-I on sleep disturbances and sleep-related outcomes, in BMI, AN symptoms, anxiety and depressive symptoms, emotionality and quality of life. These features were compared between two groups of patients with AN, one following CBT-I, and the other receiving the regular treatment at the psychiatric unit.

METHODS

Data collection occurred between January and May 2022. The study included 42 adolescents in-treatment at the Eating Disorders care specialised unit at Salvator Hospital in Marseille. They were randomly assigned to the CBT-I group (N = 31) or the control group (N = 11). Several clinical elements were assessed using sleep diaries and self-report questionnaires.

RESULTS

Participants undergoing CBT-I showed a significant improvement in sleep latency, total wake time and sleep efficacy, as well as in physical well-being. No significant effects were found regarding AN symptoms.

CONCLUSION

These preliminary findings provide support for CBT-I effectiveness in adolescents with AN, as shown by significant improvements in several sleep parameters, as well as in physical well-being. These promising results, underline the relevance of this topic and its potential benefits for a more appropriate treatment for adolescents with AN.

LEVEL OF EVIDENCE

Level V, retrospective study.

Sleep is the best medicine: assessing sleep, disordered eating, and weight-related functioning

Sleep quality is linked to disordered eating, obesity, depression, and weight-related functioning. Most research, however, has focused on clinical populations. The current study investigated relationships between sleep quality, disordered eating, and patterns of functioning in a community sample to better understand relationships among modifiable health behaviors. Participants (N = 648) recruited from Amazon Mechanical Turk completed assessments of eating, depression, weight-related functioning, and sleep. Self-reported height and weight were used to calculate body mass index (M = 27.3, SD = 6.9). Participants were on average 37.6 years (SD = 12.3), primarily female (65.4%), and White, not Hispanic (72.7%). Over half of participants endorsed poor sleep quality, and average sleep scores were above the clinical cutoff for poor sleep quality. Sleep scores were significantly positively correlated with disordered eating, depression, and weight-related functioning, even after adjusting for age, body mass index, and sex. Multivariate regression models predicting weight-related functioning and depression showed that both sleep quality and disordered eating independently predicted depression. Sleep quality did not independently predict weight-related functioning; however, disordered eating did. To the best of our knowledge, this is the first study to assess sleep behaviors, disordered eating, and weight-related functioning in a community sample of weight diverse participants. Results indicate that most participants endorsed poor sleep quality, which was associated with disordered eating patterns, including binge eating and poorer weight-related functioning, even after controlling for body mass index, highlighting that this relationship exists across the weight spectrum. These results speak to the importance of health behavior assessment and intervention within nonclinical samples.Level of evidence Level III: evidence obtained from well-designed cohort or case-control analytic studies.

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.

Examining the relationship between obstructive sleep apnoea and eating behaviours and attitudes: A systematic review

BACKGROUND

Between 60 and 90% of adults with OSA are reported as overweight. The co-existence of obesity and OSA can greatly increase an individual's risk of type 2 diabetes, metabolic syndrome and cardiovascular disease. To better understand this relationship between OSA and weight, this review aimed to investigate if there is evidence of certain eating behaviours or eating attitudes that might be found in adults living with OSA.

METHODS

We searched four databases (MEDLINE, Embase, PsycInfo and Web of Science) on January 17th, 2022, to identify studies assessing the association between eating patterns and OSA in adults. Twenty-one studies met the inclusion criteria. A narrative synthesis was conducted on the included studies, following the vote-counting method.

RESULTS

There is preliminary evidence that the time of day when calories are consumed is associated with lower OSA severity. No other clear patterns of eating behaviours or attitudes were identified however this may be due to disparity within research studies and their reported results.

CONCLUSION

Further research is needed to examine the relationship between eating times and OSA severity. We recommend standardising the approach to examining the eating patterns of those living with OSA and the relationship that this might have on OSA symptoms as well as looking at attitudes towards food in this population. This may prove helpful in providing a better understanding of the relationship between OSA and persons with overweight and help in future intervention development.

An examination of daily sleep characteristics and subsequent eating disorder behavior among individuals with binge-spectrum eating disorders

INTRODUCTION

Specific characteristics of sleep (e.g., duration, quality, and fatigue) are positively associated with (ED) behaviors, specifically binge eating (BE) potentially through decreased self-regulation and increased appetite. However, prior work has been largely cross-sectional and has not examined temporal relationships between sleep characteristics and next-day ED behaviors. Thus, the present study examined daily relationships between sleep and ED behaviors among individuals with binge-spectrum EDs.

METHOD

Participants (N = 96) completed 7 daily ecological momentary assessment (EMA) surveys over 7-14 days; morning surveys assessed sleep characteristics and 6 randomly timed surveys each day captured ED behaviors. Analyses examined within-subject and between-subject effects of sleep quality, duration, and fatigue on BE, compensatory purging behaviors, and maladaptive exercise.

RESULTS

Within-subject sleep quality was significantly negatively associated with engagement in maladaptive exercise later that day. Additionally, between-subject sleep duration was significantly negatively associated with engagement in compensatory purging behaviors.

DISCUSSION

Within- and between-subjects associations between sleep quality and duration and compensatory behavior engagement indicate that sleep plays an important role in ED behaviors. Future research should incorporate sensor-based measurement of sleep and examine how specific facets of sleep impact BE and treatment response.

LEVEL OF EVIDENCE

Level II: Evidence obtained from controlled trial without randomization.

Relationship between college lifestyle variables, eating disorder education, and eating disorder risk

Objective: This study examined relationships between eating disorder risk (EDR), lifestyle variables (e.g., exposure to healthy eating media), and differences among male and female college students. Participants: College students (N = 323) completed survey questionnaires (Fall, 2016). Fifty-three participants retook the survey at a later time. Methods: Participants completed a survey measuring EDR using EDI-3 subscales and 10 college lifestyle variables. Female and male EDR and Time 1 and Time 2 EDR were compared. Relationships between EDR and college life-style variables were examined. Results: Exercise, fewer daily meals, less face-to-face interactions, more digital interactions, less exposure to healthy eating media, and having conversations about body image were associated with EDR risk. Male college students showed an increase in EDR over time. Conclusions: Several lifestyle factors predicted EDR in college females and males. These lifestyle factors are modifiable and may be addressed by colleges during orientation and within the campus environment.

A biobehavioral circadian model of restrictive eating and binge eating

Caloric consumption occurs in rhythms, typically during daytime, waking hours, marked by peaks at mealtimes. These rhythms are disrupted in individuals with eating disorders; mealtime peaks are blunted and delayed relative to sleep/waketimes. Individuals with eating disorders also tend to experience an overall phase delay in appetite; they lack hunger earlier in the day and experience atypically high hunger later in the day, the latter of which may culminate in binge-eating episodes. This disruptive appetitive behavior-early in the day restrictive eating and later in the day binge eating-may be partially accounted for by circadian disruptions, which play a role in coordinating appetitive rhythms. Moreover, restrictive eating and binge eating themselves may further disrupt circadian synchronization, as meal timing serves as one of many external signals to the central circadian pacemaker. Here, we introduce the biobehavioral circadian model of restrictive eating and binge eating, which posits a central role for circadian disruption in the development and maintenance of restrictive eating and binge eating, highlighting modifiable pathways unacknowledged in existing explanatory models. Evidence supporting this model would implicate the need for biobehavioral circadian regulation interventions to augment existing eating disorder treatments for individuals experiencing circadian rhythm disruption. PUBLIC SIGNIFICANCE: Existing treatments for eating disorders that involve binge eating and restrictive eating mandate a regular pattern of eating; this is largely responsible for early behavioral change. This intervention may work partly by regulating circadian rhythm and diurnal appetitive disruptions. Supplementing existing treatments with additional elements specifically designed to regulate circadian rhythm and diurnal appetitive rhythms may increase the effectiveness of treatments, which presently do not benefit all who receive them.

Exploring the bidirectional relationships between night eating, loss of control eating, and sleep quality in Chinese adolescents: A four-wave cross-lagged study

OBJECTIVE

This study examined the bidirectional relationships between sleep quality, loss of control (LOC) eating, and night eating in Chinese adolescents using longitudinal data over an 18-month study period.

METHOD

Four-waves of data measurement (Waves 1-4), at 6-month intervals, were conducted with 2566 adolescents aged 11-17 years at baseline. A set of questionnaires were used to assess night eating, LOC eating, and sleep quality at each wave of data collection. Cross-lagged models were applied to analyze the bidirectional relationships between night eating, LOC eating, and sleep quality.

RESULTS

Results indicated that higher night eating scores consistently predicted poorer sleep quality and higher LOC eating scores at Waves 1, 2, and 3. Furthermore, poorer sleep quality predicted higher night eating scores at Wave 1 and Wave 3, and higher LOC eating scores predicted higher night eating scores at Wave 1 and Wave 2.

DISCUSSION

These findings highlight that night eating, LOC eating, and sleep quality were interrelated across time in Chinese adolescents. Improving sleep quality and reducing LOC eating might be promising in the prevention of night eating in adolescents. Similarly, reducing night eating might be promising in improving sleep quality and reducing LOC eating in adolescents.

PUBLIC SIGNIFICANCE

This study explored the bidirectional relationship between night eating, LOC eating, and sleep quality in Chinese adolescents using cross-lagged models. Findings indicate bidirectional relationships between these variables and highlight the potential utility in incorporating sleep, LOC eating, and night eating interventions in eating pathology prevention designs for adolescents.

Adaptive Solutions to the Problem of Vulnerability During Sleep

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

Exploring the associations between behavioral health risk factors, abnormal eating attitudes and socio-demographic factors among Chinese youth: Survey of 7,984 vocational high school students in Hunan in 2020

BACKGROUND

This study investigated the associations between behavioral health risk factors (anxiety, depression, stress, insomnia, drinking, smoking) and abnormal eating attitudes among Chinese vocational high school students (CVHSS). Potential moderating relationships were also explored with relevant socio-demographic factors of the student's age, sex, rural or urban community, household income, family type and educational level of the father and mother.

METHODS

A total of 7,984 students from three vocational high schools in Hunan, China completed a questionnaire about their socio-demographic characteristics, alcohol use, smoking, and symptoms of depression, anxiety, stress (21-item version of the Depression Anxiety Stress Scale), insomnia (8-item Athens Insomnia Scale), and abnormal eating attitudes (19-item Chinese version of Eating Attitudes Test).

RESULTS

The prevalence rates for behavioral health problems among these students ranged widely depending on the risk factor: 42.5% insomnia, 41.3% anxiety, 26.2% depression, 14.4% stress, 13.7% drinking, and 8.3% smoking. Additionally, 61.7% of students were at-risk for at least one of these six behavioral health disorders. Abnormal eating attitudes were associated with depression (r = 0.422), anxiety (r = 0.490), stress (r = 0.490), and insomnia (r = 0.375), with all of these relationships being significant (p < 0.01) and large size statistical effects. However, other analyzes found that none of the socio-demographic background factors had meaningful associations with the behavioral health risk factors (0 of 28 tests) and very few background factors were associated with the abnormal eating attitude measures (only 3 of 35 tests). Females had higher levels than males on dieting and bulimia but not on the other two eating attitude components.

CONCLUSIONS

This study determined that behavioral health risk factors (sleep problems and anxiety in particular) were common among high school students in China and that mental health and sleep disorder risks also tended to co-occur in some students with abnormal eating attitudes. Therefore, prevention and early identification programs for behavioral risk factors are needed for this population. It is important to pay more attention to students with abnormal eating attitude-related symptoms, who may have also underlying mental health problems and need further evaluation.

Shining a light on ideas worth researching in the field of eating disorders: Introduction to a Virtual Issue of the International Journal of Eating Disorders

In celebration of the 2021 International Conference on Eating Disorders, this Virtual Issue showcases Spotlight articles published since 2019 in the International Journal of Eating Disorders. Spotlight articles identify gaps in the literature and propose novel "ideas worth researching" to improve understanding, etiology, epidemiology, impacts, and prevention or treatment of eating disorders. Nine such articles are presented and are grouped thematically into: exploring mechanisms underlying distinct eating disorder symptoms (severe food restriction; driven exercise; sleep disturbance); comparing cost-effectiveness of two commonly employed treatment formats (intensive day treatment vs. outpatient treatment); harnessing technology to improve screening and treatment; and improving the reach and impact of eating disorders research. This sample of Spotlight articles illustrates the breadth and diversity of research interests in the field. We hope the Virtual Issue inspires conference delegates to generate yet further ideas worth researching so that, collectively, we make progress toward the goal of reducing the burden of suffering from eating disorders.