Disordered Eating in Young Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) was the most prevalent endocrine disorder among women. Weight issues were commonly observed and found to be associated with comorbidities. This study aimed to compare Eating Disorder Examination Questionnaire (EDE-Q) scores and Night Eating Questionnaire (NEQ) scores in patients with and without PCOS and analyze the factors associated with disordered eating. Women aged 18-25 years with and without PCOS (n = 110 for each group) were included in the study. All patients completed the EDE-Q, NEQ, Beck Anxiety, and Beck Depression inventories. Disordered eating was found more frequently in women with PCOS than in controls (25.5% vs. 2.7%, p < 0.001). There were no significant differences in NEQ scores between the two groups. Anxiety and depression scores were higher in patients with PCOS than in controls (p = 0.002 and p = 0.001, respectively). PCOS diagnosis (OR: 7.4, CI: [1.63-33.7]; p = 0.010) and high BMI (OR: 1.24, CI: [1.10-1.39]; p < 0.001) were found to be independent factors for disordered eating (EDE-Q global score ≥ 4). Disordered eating was more common in young women with PCOS compared to the control group. PCOS diagnosis and having a high BMI (> 25) were found to be independent factors related to disordered eating in young women with PCOS. Young women with a high BMI or PCOS appear to be at a higher risk of disordered eating than women of the same age. Scanning this group may help clinicians in identifying women at high risk for eating disorders and preventing comorbidities associated with them.

Evaluation of night eating syndrome and food addiction in esports players

PURPOSE

Esports players' training takes long periods and they sit for a long time during competitions, which increases their risk of obesity and urges them to develop inappropriate eating behaviors. In this study, we aimed to investigate the night-eating syndrome and food addiction in esports players.

METHODS

This cross-sectional study was conducted with 248 esports players who were members of a university's esports community. The study data were collected using an online questionnaire consisting of the descriptive information form, Night Eating Questionnaire, and Yale Food Addiction Scale.

RESULTS

The mean age of the sports players participating in the study was 22.19 ± 5.97 years. Of them, 55.6% had a normal body weight, 13.4% were obese, 54.4% played esports for 3 years or more, 13.3% experienced night eating syndrome, and 21.4% experienced food addiction. While the weekly duration of playing esports and skipping meals were associated with night eating syndrome, the weekly duration of playing esports and smoking were associated with food addiction (p < 0.05). Additionally, although there was no statistically significant difference, the risk of food addiction was 2.12 times higher in those with poor perceived sleep quality.

CONCLUSION

We observed that night eating syndrome was very common in esports players and that these individuals were at risk in terms of food addiction. Since esports has a more sedentary structure than traditional sports, we suggest that esports players should be evaluated in terms of their unhealthy eating behaviors and risk of eating disorders.

Hedonic hunger, food addiction, and night eating syndrome triangle in adolescents and ıts relationship with body mass ındex

BACKGROUND

The relationship between adolescent obesity and eating disorders is an issue that needs urgent attention. Screening for eating disorders is as important as dietary interventions to treat obesity. This study aimed to determine the relationship between hedonic hunger, food addiction, and night eating syndrome, which are considered potential risk factors for obesity, and body mass index (BMI) in adolescents.

METHODS

The data were collected through an online questionnaire. The "Power of Food Scale (PFS)" was used to assess hedonic hunger; the "Yale Food Addiction Scale for Children 2.0 (dYFAS-C 2.0)" was used to assess food addiction; and the "Night Eating Questionnaire (NEQ)" was used to assess night eating syndrome (NES)". BMI was calculated using self-reported height and weight values of adolescents. The mediated structural model analysis was performed to evaluate the effect of hedonic hunger on BMI z score via food addiction and NES.

RESULTS

The study was conducted with 614 voluntary adolescents aged between 11 and 18 years. The dYFAS-C 2.0 and NEQ scores were found to be higher in adolescents with overweight and obesity, and the BMI z-score of the adolescents had significant positive correlation with their PFS scores (p < .001). Hedonic hunger has no direct effect on BMI independent of food addiction and NES (β = - 0.051, p = .468), but when the total indirect effect is evaluated with the bootstrap analysis, it was found that one-unit increase in hedonic hunger score increases BMI z-score by approximately 0.22 units (β = 0.223, SE = 0.046, 95% CI 0.131-0.313). Hedonic hunger, food addiction, and NES together explained 5.2% of the total variance in BMI z score.

CONCLUSION

This study showed that hedonic hunger significantly predicted BMI z-score in adolescents through food addiction and NES. This emphasizes the critical importance of evaluating adolescents in terms of hedonic hunger, food addiction, and NES in the prevention, diagnosis, and treatment of obesity.

Association of participants who screened positive for night eating syndrome with physical health, sleep problems, and weight status in an Australian adult population

BACKGROUND

Night eating syndrome (NES) is a unique eating disorder characterised by evening hyperphagia and nocturnal ingestions which cause significant distress and/or impairment in functioning. Despite the growing literature, NES remains poorly understood and under diagnosed. As such, this study aims to compare the prevalence of physical health conditions in participants with NES when compared to participants without an eating disorder (ED) and participants with other eating disorders (including anorexia nervosa (AN), binge eating disorder (BED) and bulimia nervosa (BN)) in a general population Australian sample of adults.

METHODS

The data for this study were obtained from the 2017 Health Omnibus Survey (HOS) a multi-stage, cross-sectional survey, conducted by Harrison Research in South Australia. This current study focused on 2547 participants over 18 years of age and specific questions from this population survey including those related to participant demographics and health.

RESULTS

This study identified that participants who screened positive for night eating syndrome (spNES) when compared to participants with other eating disorders (ED) or no ED diagnosis, were significantly more likely to have an increased age, be female, have lower levels of education and have lower household income. Additionally, the spNES group was significantly associated with sleep apnoea (p = 0.031), insomnia or other sleep problems (p < 0.0001), increased BMI (p < 0.0001), increased levels of pain/discomfort and lower physical health-related quality of life. Hypertension, hypercholesterolemia, and diabetes were not significantly associated with the spNES group or the "other ED" group which included participants with AN, BED, BN.

CONCLUSIONS

Several physical health problems were found to be significantly associated with the spNES group including sleep problems, increased BMI, increased levels of pain and lower self-reported physical health-related quality of life. Consequently, future research exploring the complex interaction between NES and these medical conditions may provide further insight into the diagnosis, screening tools and management of NES. Additionally, this study highlights the need for future studies which use larger population-based samples.

LEVEL OF EVIDENCE

Level III. Evidence obtained from well-designed cohort or case-control analytic studies.

Prevalence of night eating syndrome among inbound call centre employees in Kuala Lumpur, Malaysia

Background: Night eating syndrome (NES) is described as a disordered eating pattern relative to sleep, where consumption of food occurs in the evening and night. Numerous studies had been conducted in various populations but studies on (NES) among call centre employees are limited. Aim: This study aimed to determine the prevalence of NES and its determinants among selected inbound call centre employees in Kuala Lumpur, Malaysia. Methods: In this cross-sectional study, a total of 217 inbound call centre employees were recruited through random sampling. A self-administered socio-demographic and work-related questionnaire was used to collect data on the background of the respondents. Information on NES and well-being was obtained by using the Night Eating Questionnaire (NEQ) and World Health Organisation-Five Well-Being Index (WHO-5) respectively. Data on dietary intakes, smoking habits, alcohol intakes and life stress were acquired using a Simple Lifestyle Indicator Questionnaire (SLIQ) while eating behaviour of the respondents was studied using the Three-Factor Eating Questionnaire (TFEQ-18). Results: The mean age of the respondents was 24.1 ± 6.0 years. The prevalence of NES was 12.0% (95% CI = 8.12-17.24). The binary logistic regression identified that NES is significantly associated with adequate exercise (AOR = 4.250, p = 0.012) and emotional eating (AOR = 6.510, p = 0.014). Conclusion: This study showed that the prevalence of NES was high in the call centre and repeated nocturnal eating can have multiple adverse health effects. Therefore, promoting healthy eating habits are crucial to reduce the impacts of NES.

Changes in Eating Behaviors and Their Relation to Weight Change 6 and 12 Months After Bariatric Surgery

INTRODUCTION

Identifying eating behaviors associated with suboptimal weight loss following bariatric surgery remains important. This study assessed the relationship between eating behaviors and weight loss following bariatric surgery in a racially diverse sample.

METHODS

Participants were assessed before surgery and 6 and 12 months postoperatively, with the Structured Clinical Interview for DSM-5, the Eating Disorder Examination-Bariatric Surgery Version, and validated measures assessing a range of eating behaviors. Linear mixed effect models were used to test the impact of eating behaviors on percent weight loss (%WL) at 6 and 12 months.

RESULTS

We enrolled 300 participants (mean age 40.1 years; BMI 45.9 kg/m2; 87% women; 62% Black and 30% White). The majority (82%) underwent sleeve gastrectomy (SG). Mean %WL was 23.0 ± 5.1% at 6 months and 26.2 ± 7.6% at 12 months. Subjective binge episodes prior to surgery predicted greater %WL over the first 12 postoperative months (p = 0.028). Postoperative disinhibition, hunger, night eating symptoms, objective binge episodes, global disordered eating attitudes and behaviors, and snacks per day were associated with smaller %WL over 12 months (all p's < 0.01). The presence of picking/nibbling and addictive-like eating behaviors was not associated with %WL at the end of the first postoperative year.

CONCLUSION

Among a diverse participant sample, problematic eating behaviors following surgery were associated with smaller %WL over 12 months. Postoperative assessment and treatment of eating behaviors are needed to address these issues as they arise and to prevent attenuation of early weight loss in some patients.

The association between night eating syndrome and health-related quality of life in Korean adults: a nationwide study

PURPOSE

Quality of life may be influenced by the presence of eating disorders. This study investigated the association between night eating syndrome (NES) and health-related quality of life in the general population.

METHODS

Data were from the 2019 Korea Community Health Survey. The presence of NES was determined using the Night Eating Questionnaire. Health-related quality of life was measured using the 3-level EuroQoL-5 Dimension Index. Multivariable linear regression analyses assessed the association between NES and health-related quality of life. Subgroup analyses were performed based on daily sleep duration.

RESULTS

A total of 34,434 individuals aged 19 years or older were included in the study population. Participants with NES (β = - 4.85, p < 0.001) reported poorer health-related quality of life scores than those without NES. Decreases in health-related quality of life scores among those with NES were greatest in those who slept over 8 h daily (β = - 12.03, p = 0.004), followed by those who slept less than 6 h (β = - 5.90, p = 0.006) and participants who slept between 6 and 8 h (β = - 3.40, p = 0.026) daily.

CONCLUSION

Individuals with NES were more likely to have a lower health-related quality of life than those without NES. These findings highlight the potential importance of considering NES in investigating the health-related quality of life.

LEVEL OF EVIDENCE

Level III, well-designed case-control analytic studies.

Night eating syndrome is associated with mental health issues among palestinian undergraduate students-cross sectional study

BACKGROUND

University students are exposed to several factors associated with Night Eating Syndrome NES, which is distinguished by nocturnal consumption and/or evening hyperphagia. The main purpose of the current study is to examine the state of NES, and to explore its relationship with selected factors (e.g. sociodemographic factors, lifestyle habits, body mass index "BMI", and mental health) among a sample of undergraduates.

METHODS

A cross-section design was done among undergraduates recruited from three universities in the southern part of Palestine. Students completed a self-administrated questionnaire including demographic information, lifestyle habits, medical profile, and the Arabic version of Night Eating Questionnaire (NEQ). Mental health status was also assessed using the Arabic version of the 12-item General Health Questionnaire (GHQ-12). Cronbach alpha was used to check the reliability of the Arabic version of NEQ. Data were analyzed using univariate and multivariate approach.

RESULTS

A total of 475 participants were included in the study, 197 (47%) males, 253(54%) females. Mean age was 19.8 ± 1.4 years, ranged from 18 to 25 years old. It is found that 141 university students (29.7%) screened positive for NES. According to univariate analysis, NES was significantly related to gender (p = 0.023), major (p = 0.005), personal monthly income (p = 0.007), source of funding (p = 0.005), and mental health (p < 0.005). Besides, the results of binary logistic regression revealed that having mental health problems (Exp (B) = 4.18; 95% CI = 2.50-6.98; p = 0.000), males (Exp (B) = 1.99; 95% CI = 1.17-3.39; p = 0.014), and those who study expenses was not covered either by scholarship or parents (Exp (B) = 2.75; 95% CI = 1.29-5.8; p = 0.08) were significantly associated with NES.

CONCLUSION

It is found that NES is common among Palestinian university students. In this study, NES was significantly more prevalent among males, and those who were studying scientific majors, having a personal income between 500 and 1000 new Israeli shekel per month, and having mental problems, and those whose studies were funded by neither by a scholarship nor by their parents.

An Updated Review of Night Eating Syndrome: An Under-Represented Eating Disorder

PURPOSE OF REVIEW

Night eating syndrome (NES) is an eating disorder that has historically been under-studied. The current review aims to summarize the most up-to-date research on NES to support better awareness.

RECENT FINDINGS

Since NES was recently included as a formal diagnosis, research on the prevalence of NES is ever evolving. Current studies underscore the high comorbidity between NES and other eating disorders, with additional complexities for patient with comorbid eating disorders. Recent findings also support the association between NES and sleep correlates, a relationship that has remained during the COVID-19 pandemic. Emerging research confirms correlates of distress in NES across cultures. There remain mixed findings between NES and BMI. There is also debate around whether age is a risk factor. Bariatric surgery research has focused on the re-emergence of NES post-operatively. Our understanding of the correlates of NES is increasing. However, research on the treatment for NES remains particularly under-studied and requires further attention.

Is poor sleep quality related to disordered eating behavior and mental health among university students?

The role of sleep in eating behavior has received increasing attention in recent years. This paper aimed to determine the prevalence and associations between sleep quality and mental health, anthropometric measurements, and disordered eating in university students. This cross-sectional research was conducted among 568 students (78.7% women) aged 18-25 years. Students completed a survey including demographic information, Pittsburgh Sleep Quality Index (PSQI), Eating Attitude Test-26 (EAT-26), Night Eating Questionnaire (NEQ), and Beck Depression Inventory (BDI). Anthropometric measurements were taken. Students were grouped based on poor (PSQI > 5) and good (PSQI ≤ 5) sleep quality. The students' average age was 20.32 ± 1.61 years. Additionally, 36.3% (n = 206) of the students had PSQI > 5, and these students had more frequent night eating syndrome (NES) and depressive symptoms. Students with PSQI > 5 had significantly higher total NEQ and BDI scores than students with PSQI ≤ 5. Significant positive correlations were found between sleep quality and its subscale scores with NEQ and BDI scores. When anthropometric measurements were evaluated according to gender, a significant difference was found between sleep quality and body mass index and waist/hip ratio in men only. There was a significant association between PSQI > 5 and NES after adjusting for age, sex, class standing, residency, smoking status, and alcohol consumption on logistic regression. Our results suggest that PSQI > 5 is a significant risk for the NES, but not other disordered eating behaviors or obesity. The relationship between sleep, depression, anthropometric measurements, and disordered eating should be further evaluated in future studies.

Night eating, weight, and health behaviors in adults participating in the Daily24 study

BACKGROUND

Night eating syndrome (NES) is associated with adverse health outcomes. This study evaluated the relationship between night eating severity, weight, and health behaviors.

METHODS

Participants (N = 1017; 77.6% female, mean Body Mass Index (BMI) = 30.5, SD = 7.8 kg/m², age = 51.1, SD = 15.0 years) were recruited from three health systems. Participants completed the Night Eating Questionnaire (NEQ) and questionnaires assessing sleep, chronotype, physical activity, diet, weight, and napping.

RESULTS

In the overall sample, higher NEQ scores were associated with higher BMI (p < .001) and consumption of sugar-sweetened beverages (p < .001), as well as lower fruit/vegetable consumption (p = .001). Higher NEQ scores were associated with increased odds of having overweight/obesity (p < .001), eating fast food (p < .001), moderate-vigorous physical activity (p = .005), and smoking (p = .004). Participants who exceeded the screening threshold for NES (n = 48, 4.7%) reported elevated BMI (p = .014), an increased likelihood of overweight/obesity (p = .004), greater sugar-sweetened beverages consumption (p < .001), napping less than twice per week (p = .029), shorter sleep duration (p = .012), and a later chronotype (M = 4:55, SD = 2:45).

CONCLUSION

Night eating severity was associated with obesity and intake of fast food and sugar-sweetened beverages. Interventions to address night eating and associated behaviors may enhance the efficacy of weight management interventions and promote engagement in positive health behaviors.

Personality traits and night eating syndrome in women with bulimia nervosa and binge eating disorder

PURPOSE

Previous research suggests that eating disorders may be associated with certain personality profiles; however, there is limited research investigating associations with night eating syndrome (NES). This research suggests harm avoidance personality trait is higher in NES individuals than in the general population, however, evidence of associations with other personality traits is inconsistent. To understand which personality traits are associated with NES symptoms, the current study aimed to improve understanding of the relationship between NES symptoms and a range of personality traits, addressing limitations in the earlier literature in this area by controlling for common confounders.

METHODS

Baseline data were analysed from an outpatient psychotherapy trial for 111 women with bulimia nervosa or binge eating disorder. Pre-treatment measures of personality traits (measured with the Temperament and character inventory-revised) and NES symptoms (measured with the Night eating questionnaire) were used. Regression analyses tested associations between these variables, adjusting for potential confounders, including age and ethnicity.

RESULTS

Low cooperativeness scores were associated with greater NES symptoms in the multivariable model (mean difference: - 0.10, 95% confidence intervals: - 0.20 to - 0.01, p = 0.033). There was weak evidence of associations between both high harm avoidance and low self-directedness personality traits and greater NES symptoms.

CONCLUSIONS

This study adds to the limited research measuring associations between a range of personality traits and NES, addressing limitations of previous research. Weak evidence for an association between high harm avoidance and low self-directedness and increased NES symptoms was found. A novel association was found between low cooperativeness and greater NES symptoms. Further research is needed to validate its presence in those with and without comorbid eating disorders and to examine the relative change in NES, eating disorder symptoms and personality scores in treatments focusing on cooperativeness.

LEVEL OF EVIDENCE

Level IV (cross-sectional data from a randomised controlled trial, CTB/04/08/139).

Adult attachment anxiety is associated with night eating syndrome in UK and US-based samples: Two cross-sectional studies

Previous research has shown that "attachment anxiety" is a robust predictor of disinhibited eating behaviours and that this relationship is underpinned by difficulties in managing emotion. Night eating syndrome (NES), a proposed eating disorder characterized by evening hyperphagia, nocturnal awakenings to eat, and morning anorexia, is also associated with eating to manage emotion. Across two studies (N = 276 &N = 486), we considered a relationship between attachment anxiety and NES. In Study 1, we hypothesised (pre-registered) that attachment anxiety would predict NES score and that this relationship would be mediated by disinhibited eating. Participants were asked to complete questionnaire measures of attachment orientation, disinhibited eating (emotional and uncontrolled eating) and NES. Our parallel mediation model confirmed a direct relationship between attachment anxiety and NES (p < .001) and showed an indirect path via both emotional (95% CI: 0.15-0.63) and uncontrolled eating (95% CI: 0.001-0.36). In Study 2, we showed that fear of negative evaluation of eating significantly mediated a reversed relationship between attachment anxiety and NES (95% CI: 0.02-0.04). Finally, across both studies we used a novel tool to assess "eating to cope". We showed a relationship with emotional eating but failed to show a robust relationship with NES. Attachment orientation may represent a potential intervention target for night eating syndrome. Future research should consider a longitudinal approach to strengthen our understanding of directionality amongst these factors.

'In the night kitchen': A scoping review on the night eating syndrome

BACKGROUND

First described in 1955, night eating syndrome refers to an abnormal eating behavior clinically defined by the presence of evening hyperphagia (>25% of daily caloric intake) and/or nocturnal awaking with food ingestion occurring ⩾ 2 times per week.

AIMS

Although the syndrome is frequently comorbid with obesity, metabolic and psychiatric disorders, its etiopathogenesis, diagnosis, assessment and treatment still remain not fully understood.

METHODS

This review was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines; PubMed database was searched until 31 October 2020, using the key terms: 'Night Eating Syndrome' AND 'complications' OR 'diagnosis' OR 'drug therapy' OR 'epidemiology' OR 'etiology' OR 'physiology' OR 'physiopathology' OR 'psychology' OR 'therapy'.

RESULTS

From a total of 239 citations, 120 studies assessing night eating syndrome met the inclusion criteria to be included in the review.

CONCLUSION

The inclusion of night eating syndrome into the Diagnostic and Statistical Manual of Mental Disorders-5 'Other Specified Feeding or Eating Disorders' category should drive the attention of clinician and researchers toward this syndrome that is still defined by evolving diagnostic criteria. The correct identification and assessment of NES could facilitate the detection and the diagnosis of this disorder, whose bio-psycho-social roots support its multifactorial nature. The significant rates of comorbid illnesses associated with NES and the overlapping symptoms with other eating disorders require a focused clinical attention. Treatment options for night eating syndrome include both pharmacological (selective serotonin reuptake inhibitors, topiramate and melatonergic drugs) and non-pharmachological approaches; the combination of such strategies within a multidisciplinary approach should be addressed in future, well-sized and long-term studies.

Effects of night eating and binge eating disorders on general health in university students in Lebanon

BACKGROUND

Eating disorders (EDs) have an important impact on both physical and mental wellbeing, especially in a young population. There is a lack in research about EDs in the Middle East, and especially in Lebanon, where the co-occurring obesity is a widespread health problem.

AIM

Our study aims to assess the relation between night eating syndrome (NES) with binge eating disease (BED) and obesity (BMI) on one hand, and between NES and general health on the other hand, in university students.

MATERIALS AND METHODS

An observational cross-sectional study was conducted on 460 university students in Lebanon. Data collection was carried out using an online questionnaire. Socio-demographic and general health characteristics, BMI, Arabic validated General Health Questionnaire (GHQ-12), Arabic validated Binge Eating Scale (BES) and the Night Eating Diagnostic Questionnaire (NEDQ). Statistical analysis was accomplished on SPSS.

RESULTS

Participants having highest income showed highest NEDQ score. Females and participants with a history of eating disorders were more likely to have BED. A significant correlation was also found between having an ED history and negative impact on general health. BMI was correlated with both NEDQ and BES. Having NES was associated with also having BED. Furthermore, those with NES showed higher scores regarding GHQ-12.

CONCLUSION

Relatively high prevalence of NES and BED was noted in university students in Lebanon. This was correlated to a household income, general health, and BMI. The repercussion on both physical and mental morbidities highlights the importance for stepping up of the Lebanese organizational system to perform periodic screening.

Addiction-like response in brain and behavior in a rat experimental model of night-eating syndrome

STUDY OBJECTIVES

Individuals ailing from night eating syndrome (NES) consume more than 25% of their daily food intake during the normal sleep time, delaying their sleep or waking up in the middle of the night to eat. This study explored two experimental conditions resembling NES in Wistar rats by offering palatable food during the sleep phase, alone or combined with sleep delay. Also we explored their impact on addiction-like changes in the brain and behavior.

METHODS

Experiment 1 explored the brain response after a first NES-like event; experiment 2 and 3 explored addiction-like behaviors c-Fos and FosB/ΔFosB in corticolimbic regions after 4 weeks exposition to NES-like conditions and after one week of withdrawal, respectively. For all 3 experiments 6 experimental groups were used: 1. Control; 2. Restricted access (1 h) to high-sugar diet (HSD) or to 3. high-fat diet (HFD); 4., Sleep delay for 4 h (SD) (from ZT0-ZT4, rats using slow rotating wheels); 5. SD + HSD; 6. SD + HFD.

RESULTS

A first event of eating a palatable diet with or without SD was sufficient to stimulate c-Fos and ΔFosB. Along 4 weeks of exposure to the palatable diets rats exhibited escalation and binge eating, which was highest for the HFD. At this stage, SD did not influence behavioral changes nor the neuronal response. After one-week in withdrawal, rats exhibited craving and effort to obtain their palatable diet. The brains of rats previously exposed to sleep delay maintained high levels of FosB/ΔFosB in the accumbens shell and high c-Fos activation in the insular cortex.

CONCLUSIONS

In our experimental models of NES-like a HFD in the sleep phase and SD are risk factors to develop binge eating and addiction-like behaviors.

Dietary patterns of patients with binge eating disorders with and without night eating

OBJECTIVE

This study aimed to compare dietary patterns (timing and frequency of binge episodes, caloric intake and macronutrient composition) of patients with binge eating disorders (BE) with and without night eating syndrome (NES).

DESIGN

The study includes 59 women (18-60) who sought treatment for Eating Disorders (EDs) and were diagnosed with BED or BN (BE) with or without NES. They were divided into two groups: NES-BE and BE-only. The participants kept 7-day, 24-h food diaries and completed demographic and depression questionnaires.

RESULTS

NES-BE reported significantly a higher frequency of binge days and binge episodes during the week, and more energy and fat consumption than BE-only.

CONCLUSIONS

Individuals with NES-BE exhibit higher levels of eating pathology than individuals with BE-only. Thus, NES-BE may not be simply a variant of BED or BN but rather a separate entity that may lead to a more severe disorder and require early assessment and more intensive and suitable treatment.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

Night eating syndrome: a psychiatric disease, a sleep disorder, a delayed circadian eating rhythm, and/or a metabolic condition?

Introduction: Night Eating Syndrome (NES) refers to an abnormal eating behavior which presents as evening hyperphagia consuming >25% calorie intake and/or nocturnal awaking with food ingestion which occurs ≥2 times per week. Although the syndrome has been described more than seven decades ago, the literature has been growing slowly on its etiology, diagnosis, and treatment. Areas covered: The proposed treatment options for NES are all at a case-study level. Moreover, our understanding of its etiology, comorbidities, and diagnosis is still premature. We performed a literature review in Medline/PubMed to identify all the studies proposing a management plan for NES and summarized all the existing data on its diagnosis and treatment. Expert opinion: To date, none of the proposed treatment options for NES have been promising and long-term data on its efficacy is lacking. The slow growth of evidence on this debilitating but underreported condition may be due to unawareness among clinicians, under-reporting by patients, and unrecognized diagnostic criteria. Objective screening of symptoms during office visits especially for patients at a high-risk for NES will identify more patients suffering from the syndrome.

Dysfunctional eating in type 2 diabetes mellitus: A multicenter Italian study of socio-demographic and clinical associations

BACKGROUND AND AIMS

Dysfunctional eating might impact on the management and metabolic control of type 2 diabetes (T2DM), modifying adherence to healthy diet and food choices.

METHODS AND RESULTS

In a multicenter study, we assessed the prevalence of dysfunctional eating in 895 adult outpatients with T2DM (51% males, median age 67, median BMI 30.3 kg/m²). Socio-demographic and clinical characteristics were recorded; dysfunctional eating was tested by validated questionnaires (Eating Attitude Test-EAT-26, Binge Eating Scale-BES; Night Eating Questionnaire-NEQ); food intake and adherence to Mediterranean diet were also measured (in-house developed questionnaire and Mediterranean Diet Score-MDS). Obesity was present in 52% of cases (10% obesity class III), with higher rates in women; 22% had HbA1c ≥ 8%. The EAT-26 was positive in 19.6% of women vs. 10.2% of men; BES scores outside the normal range were recorded in 9.4% of women and 4.4% of men, with 3.0% and 1.5% suggestive of binge eating disorder, respectively. Night eating (NEQ) was only present in 3.2% of women and 0.4% of men. Critical EAT and BES values were associated with higher BMI, and all NEQ + ve cases, but one, were clustered among BES + ve individuals. Calorie intake increased with BES, NEQ, and BMI, and decreased with age and with higher adherence to Mediterranean diet. In multivariable logistic regression analysis, female sex, and younger age were associated with increase risk of dysfunctional eating.

CONCLUSION

Dysfunctional eating is present across the whole spectrum of T2DM and significantly impacts on adherence to dietary restriction and food choices.

Associations between night eating syndrome and metabolic parameters in pregnant women

Objective:

In this study, we aimed to evaluate the incidence of night eating in pregnancy and the relationship between night eating scores and nutritional status, insulin resistance, and lipid profile in pregnant women.

Materials and Methods:

In this study, 148 pregnant women who presented to the Gynecology and Obstetrics Clinics at Konya Training and Research Hospital in Konya were divided into two groups according to their night eating scores. These two groups were compared in terms of their nutritional attitudes and metabolic parameters.

Results:

Comparisons of participants meeting night eating syndrome (NES) scores versus women without NES indicated that patients with NES exhibited fever hunger at breakfast time, more breakfast skipping (p<0.05) than those without NES. Also homeostatic model assessment insulin resistance, insulin, and high-density lipoprotein cholesterol parameters were significantly higher in pregnant women in the NES group (p<0.05). Also, correlations were found between higher night eating questionnaire total scores and higher HbA1c, insulin resistance, insulin, and more breakfast skipping.

Conclusion:

The results of this study suggest that night eating symptoms during pregnancy may increase and this is able to effect glucose metabolism.

A Review of the Relationship between Night Eating Syndrome and Body Mass Index

PURPOSE OF THE REVIEW

To review literature on night eating syndrome (NES) and body mass index (BMI, kg/m²) published in the last 5 years.

RECENT FINDINGS

Since December, 2013, 11 studies examined the association between NES and BMI. Five of these studies reported a positive relationship, five showed no relationship, and one produced mixed findings. Emotional eating and age were moderators. Twelve studies examined whether there was a difference in BMI between those with and without NES with only five of these finding differences. A primary weakness of the recent literature base is that it is almost entirely cross-sectional. Recent findings regarding the relationship between NES and BMI are mixed. Future research should examine the relationship between these variables longitudinally and continue to examine moderating variables that explain why some individuals manifest excess weight with NES and others do not.

Psychometric properties and gender invariance of the simplified Chinese version of Night Eating Questionnaire in a large sample of mainland Chinese college students

PURPOSE

The Night Eating Questionnaire (NEQ) is the most frequently used instrument for assessing night eating syndrome (NES), and it has been translated to many languages, including a traditional Chinese version in Taiwan. However, significant differences exist in the social, linguistic, and cultural contexts between mainland China and Taiwan. For its use in mainland China, a simplified Chinese version is needed and its psychometric properties should be further evaluated. Thus, the current study aimed to obtain a simplified Chinese NEQ (SC-NEQ) and validate its psychometric properties.

METHODS

According to standard procedures, the SC-NEQ was obtained by language transformation from the traditional Chinese version of NEQ. The SC-NEQ was then administered to 1273 mainland Chinese college students recruited from three provinces in mainland China.

RESULTS

The four-factor structure of the original English NEQ (morning anorexia, evening hyperphagia, mood/sleep, and nocturnal ingestions) was confirmed in the current sample. Moreover, a second-order model also fitted the data well. The SC-NEQ showed good reliability with a Cronbach's alpha and omega of 0.70 and 0.83, respectively. The total score of the SC-NEQ was significantly and moderately correlated with eating pathology (r = .35, p < .01). Strong measurement invariance across gender groups was also supported.

CONCLUSIONS

These findings suggest that the SC-NEQ can be a useful tool to assess NES in mainland China.

LEVEL OF EVIDENCE

V, descriptive (cross-sectional) study.

Factor structure of the Night Eating Diagnostic Questionnaire (NEDQ) and an evaluation of the diagnostic criteria of the night eating syndrome

BACKGROUND

The Night Eating Diagnostic Questionnaire (NEDQ) is a validated assessment of the night eating syndrome (NES) based on the proposed diagnostic criteria. While past results show that NEDQ is associated with psychopathology and body mass index (BMI), the relationships between the proposed NES diagnostic criteria and psychopathology and BMI have not been investigated. Thus, the relationships between the proposed NES diagnostic criteria and factors previously associated with NES, namely depression, "food addiction" (FA), sleep quality, and BMI were examined. Finally, the NEDQ factor structure was examined for the first time in order to determine whether the NEDQ is assessing NES appropriately.

METHODS

The NEDQ, depression, sleep quality, and FA questionnaires were administered to a sample of older community members (n = 468) and a student sample (n = 254). Principal Components Analysis (PCA) was performed to examine the factor structure of the NEDQ. The relationships between the proposed diagnostic criteria and depression, sleep quality, FA, and BMI were examined using multiple regression.

RESULTS

The proposed NES criteria were highly intercorrelated. PCA revealed a single factor solution for the NEDQ. In the community sample, depression was associated with the presence of five of nine proposed diagnostic criteria while poor sleep quality and FA were associated with the presence of seven and six criteria respectively. In the community sample, only the sleep problems and impairment/distress criteria were positively associated with BMI. In the student sample, fewer criteria were associated with psychopathology, and no criteria were associated with BMI.

CONCLUSIONS

These findings support the proposed criteria for diagnosis of NES. All proposed criteria were associated with at least one psychopathology measure. BMI was only associated with the sleep problems and impairment/distress criteria in the community sample. The PCA finding of a single factor indicates that the NEDQ is a cohesive assessment of NES, and that the NEDQ is a good measure of NES criteria.

Night eating syndrome in patients with eating disorders: Is night eating syndrome distinct from bulimia nervosa?

BACKGROUND/PURPOSE

Night eating syndrome (NES) is a diagnosis newly introduced in the fifth version of the Diagnostic and Statistical Manual of Mental Disorders. This study investigated the characteristics of NES in individuals with eating disorders and the clinical significance of NES in individuals with bulimia nervosa (BN).

METHODS

We recruited participants with eating problems at psychiatric outpatient clinics and from Internet referrals and age, sex, and educational level-comparable controls from September 2013 to April 2017. All participants received in-face structured clinical interviews to establish their eating disorder and NES diagnoses and completed questionnaires assessing NES, eating attitudes/behaviors, depression, sleep disturbances, morningness/eveningness preference, and functional impairment. Comparisons of measurements were made across patients with eating disorder subtypes and across patients with NES-only, BN-only, comorbid BN and NES, and controls.

RESULTS

NES was identified in 10.3%, 34.9%, and 51.7% of the individuals with anorexia nervosa, BN, and binge-eating disorder, respectively. NES-only group had more frequent binge-eating, higher degrees of eating pathology, depression, sleep disturbances, and functional impairment compared to controls; however, NES-only group shared similar levels of disordered eating, depression, sleep disturbances, and functional impairment with BN-only group. BN-NES group had no difference from BN-only group on most eating pathology, psychopathology, and functional impairment, except for the presence of greater eating and weight concerns.

CONCLUSION

NES has its clinical significance; however, it overlaps with BN in several dimensions of psychopathology. Presence of night eating in a BN group may not contribute clinically meaningful psychopathology.

The relationship between night eating symptoms and disordered eating attitudes via insomnia and chronotype differences

Humans' sleep timing and the psychological construct "diurnal preference" determines their "chronotype" (i.e., morning or evening type). Diurnal preferences can affect sleep-awake rhythms and eating behaviors. Our aim in this study was to examine the relationship between night eating symptoms and disordered eating attitudes by evaluating insomnia and chronotype differences in university students. The participants, 383 university students, filled out a package of psychological tools, including the Morningness-Eveningness Questionnaire, the Insomnia Severity Index, the Night Eating Questionnaire, and the Eating Attitude Test. One way analysis of variance was used to investigate the relationship of chronotypes with scale scores, and mediation regression analysis was used to investigate the indirect effects of night eating symptoms on disordered eating attitudes. Insomnia and night eating scores of the participants varied statistically according to chronotypes, and both insomnia and night eating scores were associated with the evening type. Findings show that night eating symptoms have a direct effect on the chronotype differences and insomnia and an indirect effect on disordered eating attitudes, by increasing insomnia scores. In conclusion, night eating syndrome may represent the misalignment of food intake and may shift the circadian rhythm to delayed sleep phase, acting as a peripheral oscillator in human.

Why I eat at night: A qualitative exploration of the development, maintenance and consequences of Night Eating Syndrome

Night Eating Syndrome (NES), as a diagnosis, presents as a combination of disordered eating, sleep and mood. Patients identified as having both NES and obesity demonstrate poorer outcomes in terms of weight loss compared to those with NES only. However, research focusing on psychological factors associated with NES remains relatively underdeveloped. This study aimed to explore the relationship between NES and the experience of emotion from the perspective of patients accessing a weight management service. Ten adults who met diagnostic criteria for moderate or full NES took part in a semi-structured interview. Data were analysed using a constructivist approach to grounded theory. A core concept to emerge from the analysis was termed 'emotional hunger'; reflecting an urge or need to satiate a set of underlying unmet emotional needs. It was underpinned by the following interrelated themes: (1) Cultivating a dependency on food; (2) Relying on food to regulate emotions; (3) Understanding the significance of night-time; (4) Acknowledging the consequences of night eating. This study provides an in-depth understanding of the relationship between NES and the experience of emotion from the perspective of patients attending a weight management service. Results have potential to inform future service development, particularly around the adoption of a more holistic approach to night eating behaviours.

Are Eating Disorders Risk Factors for Type 2 Diabetes? A Systematic Review and Meta-analysis

RECENT FINDINGS

Eating disorders (ED) affect energy intake modifying body fat depots. Prior evidence suggests that binge eating disorder (BED) and bulimia nervosa (BN) could increase the risk for type 2 diabetes (T2D), while anorexia nervosa (AN) could reduce it.

PURPOSE OF REVIEW

A systematic review and meta-analysis were conducted to evaluate if ED are risk factors for T2D. Ten studies were selected out of 1057 screened. Meta-analysis of six studies with T2D as outcome is reported. Among cross-sectional studies, both BED (OR 3.69, 95% CI [1.12-12.12]) and BN (OR 3.45 [1.92-6.1]) increased the risk of T2D, while AN was not associated with lower risk (OR 0.87 [0.40-1.88]). Cohort studies showed increased risk of T2D with BN (RR 1.7 [1.2-2.5]), and decreased risk with AN (RR 0.71 [0.52-0.98]), but for BED the association was less clear (OR 3.34 [0.85-13.12]). Limitations of studies and recommendations for future research are presented.

Prevalence, demographic correlates, and association with psychological distress of night eating syndrome among Chinese college students

Night eating syndrome (NES) has primarily been studied in Western societies, and the prevalence and associated factors of NES in China still remain unknown. This study examined the prevalence, demographic correlates, and association with psychological distress of NES among Chinese college students. By using the Chinese version of Night Eating Questionnaire (C-NEQ), data were collected from 909 university students sampled from three provinces in China. Results showed that the prevalence of NES was 2.8% (2.4% after excluding students with binge eating); the occurrence of NES was correlated with gender ([Formula: see text]) and the higher night eating scores were significantly correlated with higher psychological distress (rs = .396-.471, ps < .001). Because of the huge population base in China, there could be a large number of Chinese college students with NES. Therefore, more attention is needed for prevention, detection, and treatment of NES for Chinese college students.

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.

Eating disoders in type 2 diabetic people: Brief review

BACKGROUND

Relationship between type 1 diabetes and Eating disorders is well-known, less information exists on the relationship between type 2 diabetes (T2DM) people and eating disorders.

AIM

Review information on the prevalence and impact of type 2 diabetes and eating disorders comorbidity.

METHODS

Search in Medline and PubMed relevant articles on the aforementioned co-morbidity. Review includes articles on epidemiological, clinical and therapeutics aspects.

CONCLUSIONS

Disordered eating behaviours may affect around 40% of T2DM people, being the predominant clinical forms: Eating Disorders Non otherwise specified (EDNOS), Night Eating Syndrome (NES) and Binge Eating Disorder (BED), however, population-based estimates of T2DM and ED comorbidity are mandatory to determine the prevalence of ED in T2DM people. The association between both entities has a consequence which is an impairment of metabolic control, associated to increase risk of vascular complications and difficult body weight loss, basis of T2DM treatment.

Sleep and Eating Disorders

Insomnia is related to an increased risk of eating disorders, while eating disorders are related to more disrupted sleep. Insomnia is also linked to poorer treatment outcomes for eating disorders. However, over the last decade, studies examining sleep and eating disorders have relied on surveys, with no objective measures of sleep for anorexia nervosa or bulimia nervosa, and only actigraphy data for binge eating disorder. Sleep disturbance is better defined for night eating syndrome, where sleep efficiency is reduced and melatonin release is delayed. Studies that include objectively measured sleep and metabolic parameters combined with psychiatric comorbidity data would help identify under what circumstances eating disorders and sleep disturbance produce an additive effect for symptom severity and for whom poor sleep would increase risk for an eating disorder. Cognitive behavior therapy for insomnia may be a helpful addition to treatment of those with both eating disorder and insomnia.

Bright light therapy for the treatment of night eating syndrome: A pilot study

The effect of bright light therapy (BLT) on the symptoms of night eating syndrome was evaluated. Fifteen adults completed two weeks of daily 10,000 lux BLT administered in the morning. Significant reductions were found pre-to-post treatment in night eating symptomatology, mood disturbance, and sleep disturbance. This pilot trial provides preliminary support for the efficacy of BLT for the treatment of night eating syndrome.

New data on psychological traits and sleep profiles of patients affected by nocturnal eating

OBJECTIVE

Nocturnal eating behavior is shared by patients affected by a parasomnia, sleep-related eating disorder (SRED), and several eating disorders such as night eating syndrome (NES) and binge-eating disorder (BED); however, the differential clinical features of these patients have been poorly studied, with persisting difficulties in defining the borders between these pathologies. The aim of this study was to evaluate polysomnographic and personality characteristics of nocturnal eaters to further differentiate the syndromes.

METHODS

During a period of six months, consecutive patients complaining of nocturnal eating were asked to participate to the study. Twenty-four patients who were found to eat during the polysomnographic recording (PSG) study, and gender-matched control subjects were included. All subjects underwent a full-night video-PSG study and a psychometric assessment including the Eating Disorder Inventory (EDI-2), the self-rating Bulimic Investigatory Test-Edinburgh (BITE), the Temperament and Character Inventory (TCI), and the Barratt Impulsivity Scale (BIS).

RESULTS

Nocturnal eaters showed a mild reduction in sleep efficiency and duration due to a moderate sleep fragmentation, whereas the percentage of each sleep stage was not significantly affected. Nocturnal eaters scored higher at many subscales of the EDI-2, at the BITE symptoms subscale, and at the BIS attentional impulsivity subscale.

CONCLUSION

The psychological characteristics found in our patients with NES seem to be typical for patients affected by eating disorders, and support the hypothesis that the nocturnal behavior of these individuals is due to an eating disorder; however, specific traits also allow differentiation of NES from BED.

Night Eating Syndrome in Major Depression and Anxiety Disorders

INTRODUCTION

The purpose of this study is to investigate the prevalence and the clinical features of night eating syndrome (NES) in patients with depression and anxiety disorders.

METHOD

The study was conducted at Bakırköy State Hospital for Mental Health and Neurological Disorders. Three-hundred out-patients who had major depression (MD), panic disorders (PD), general anxiety disorders (GAD) and obsessive-compulsive disorders (OCD) participated in the study. The semi-structured socio-demographic form, the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Night Eating Questionnaire, and NES Evaluation Questionnaire were implemented.

RESULTS

In our sample, the prevalence of the NES was 15.7% (n=47). NES frequency was significantly higher in the patients diagnosed with major depression (MD 22%, GAD 7.8%, OCD 12.5%, PD 14%). Smoking, presence of past suicide attempts, rates of antipsychotic drugs use, and average scores of body mass index (BMI) were significantly higher in the patients who had NES. In this sample, depression, BMI, and smoking were found to be determinants of NES.

CONCLUSION

This study shows that NES may be frequently observed in patients admitted to psychiatric clinics, especially in those with major depression. Evaluation of NES in psychiatric patients may help the treatment of the primary psychopathology and prevent the adverse effects, like weight gain, which may reduce the quality of life.

Nonnormative eating behavior and psychopathology in prebariatric patients with binge-eating disorder and night eating syndrome

BACKGROUND

Binge-eating disorder (BED) as a distinct eating disorder category and night eating syndrome (NES) as a form of Other Specified Feeding or Eating Disorders were recently included in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). This study sought to investigate the prevalence of BED and NES and associations with various forms of nonnormative eating behavior and psychopathology in prebariatric patients. Within a consecutive multicenter registry study, patients in 6 bariatric surgery centers in Germany were recruited.

METHODS

Overall, 233 prebariatric patients were assessed using the Eating Disorder Examination and self-report questionnaires. Assessment was unrelated to clinical procedures.

RESULTS

Diagnostic criteria for full-syndrome BED and NES were currently met by 4.3% and 8.2% of prebariatric patients, respectively. In addition, 8.6% and 6.9% of patients met subsyndromal BED and NES criteria, respectively. Co-morbid BED and NES diagnoses were present in 3.9% of patients. In comparison to patients without any eating disorder symptoms, patients with BED and NES reported greater emotional eating, eating in the absence of hunger, and more symptoms of food addiction. Moreover, differences between patients with BED and NES emerged with more objective binge-eating episodes and higher levels of eating concern, weight concern, and global eating disorder psychopathology in patients with BED.

CONCLUSION

BED and NES were shown to be prevalent among prebariatric patients, with some degree of overlap between diagnoses. Associations with nonnormative eating behavior and psychopathology point to their clinical significance and discriminant validity.

Prevalence and clinical significance of night eating syndrome in university students

PURPOSE

Most studies of night eating syndrome (NES) fail to control for binge eating, despite moderate overlap between the two conditions. Establishing the independent clinical significance of NES is imperative for it to be considered worthy of clinical attention. We compared students with and without NES on eating disorder symptomatology, quality of life, and mental health, while exploring the role of binge eating in associations.

METHODS

Students (N = 1,636) ages 18-26 years (M = 20.9) recruited from 10 U.S. universities completed an online survey including the Night Eating Questionnaire (NEQ), Eating Disorder Examination-Questionnaire (EDE-Q), Project Eating Among Teens, and the Health-Related Quality of Life-4. NES was diagnosed according to endorsement of proposed diagnostic criteria on the NEQ. Groups (NES vs. non-NES) were compared on all dependent variables and stratified by binge eating status in secondary analyses.

RESULTS

The prevalence of NES in our sample was 4.2%; it decreased to 2.9% after excluding those with binge eating. Body mass index did not differ between groups, but students with NES were significantly more likely to have histories of underweight and anorexia nervosa. In students with NES, EDE-Q scores were significantly higher; purging, laxative use, and compulsive exercise were more frequent; quality of life was reduced; and histories of depression, attention-deficit/hyperactivity disorder, and self-injury were more common. Binge eating did not account for all of these differences; the presence of it and NES was associated with additive risk for psychopathology on some items.

CONCLUSIONS

NES may be a distinct clinical entity from other DSM-5 eating disorders.

Personality Traits in Obesity Associated with Binge Eating and/or Night Eating

Specific personality traits, as assessed by the Temperament and Character Inventory (TCI), have been identified in individuals with obesity, but their association with binge and/or night eating has scarcely been reported. Indeed, our systematic search of Medline (1987 to 2013) yielded only five studies on the issue. Taken together, they suggest that personality traits do not have any significant role in determining body mass index, and therefore obesity class. However, obese individuals, in comparison with normal weight individuals, do seem to have a distinctive personality profile, characterized by low self-directedness and cooperativeness, and obese individuals with binge eating show lower self-directedness than those without. Moreover obese individuals with binge eating and/or night eating share a temperament profile characterized by high novelty-seeking and harm-avoidance, two traits also observed in other eating disorder categories and in clinical depression. Future longitudinal studies are needed to investigate the role of personality traits in the onset of binge eating and night eating in obese individuals, and to clarify their influence, if any, on treatment outcomes. Such information will enable us to determine whether the evaluation of personality traits should be included in the comprehensive assessment of obese individuals.

Neuroendocrine Profile in the Night Eating Syndrome

Night eating syndrome (NES) has recently been getting more attention as a recognized eating disorder. NES is characterized by a delay in the circadian pattern of food intake, associated with morning anorexia, evening hyperphagia, awakenings from sleep with ingestion of food, depressed mood, and obesity. Although the behavioral characteristics of NES were first described in 1955, the neuroendocrine characteristics have only been described recently. Researchers have examined several hormones that appear to differ in night eaters compared to controls, including melatonin, leptin, and cortisol. Researchers have more recently examined the hypothalamic-pituitary-adrenal axis in more detail, with emphasis on corticotrophin releasing hormone. Further studies have examined ghrelin, growth hormone, prolactin, and IGF-1, with differences observed in the circadian pattern of these hormones in those with NES compared to controls. Despite increasing interest in the neuroendocrine profile of night eating behavior, the biological basis of NES is still not well understood.

Delayed Timing of Eating: Impact on Weight and Metabolism

Animal studies of delayed eating have provided useful information regarding the potential relationship between nighttime eating and increased weight and metabolic dysregulation, which occur in the absence of increased locomotion or increased caloric intake. We first review recent studies detailing these relationships and possible mechanisms in rodents. We then examine human data showing that sleep restriction leads to increased energy intake and weight gain, followed by a review of the human phenotype of delayed eating, night eating syndrome, and its relation to weight and metabolism. Finally, we examine human experimental studies of delayed eating and discuss preliminary data that show slight weight gain, dysfunction in energy expenditure, and abnormalities in the circadian rhythms of appetitive, stress, and sleep hormones. Well-controlled, longer-term experimental studies in humans are warranted to test the effect of delayed eating without sleep restriction to clarify whether limiting or eliminating nighttime eating could lead to weight loss and significantly improve related disorders, such as diabetes and heart disease, over time.

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.

The Treatment of Night Eating Syndrome: A Review and Theoretical Model

The treatment of night eating syndrome, a disorder characterized by evening hyperphagia, morning anorexia, and insomnia, continues to gain attention with its inclusion in the DSM-V. Known treatments for NES include pharmacological, phototherapy, weight loss and dietary, and psychological interventions, which, together with the syndrome's clinical characteristics, support a treatment guiding biobehavioral model. The biobehavioral model proposes that a genetic predisposition, coupled with stress, enhances midbrain serotonin transporter (SERT) binding, which results in lower post-synaptic serotonin, dysregulating circadian rhythms and decreasing satiety. Selective serotonin reuptake inhibitors should therefore decrease SERT binding, increase postsynaptic serotonin, and restore circadian function and satiety regulation. Psychological interventions may be used to decrease stress as well as address insomnia and circadian rhythm disruptions. Dietary and behavioral interventions may produce beneficial changes in satiety as well as dysregulated eating. Avenues for future treatment outcome studies, including alternative pharmacological and combination therapies, are discussed.

Using the Neuroscience of Obesity, Eating Behavior, and Sleep to Inform the Neural Mechanisms of Night Eating Syndrome

The development and maintenance of night eating syndrome (NES) is likely influenced by physiological, psychological, and social factors. Within the physiological domain, neural mechanisms (e.g., neurotransmitters and specific brain region functioning) remain understudied in contrast to other eating disorders and obesity. The serotonin system has been hypothesized to contribute to NES based on one single photon emission computed tomography (SPECT) study and supportive pharmacologic treatment outcome findings, but additional neural models are plausible. Functional magnetic resonance imaging (fMRI) is a brain imaging tool that is increasingly being used to study obesity, eating behavior, and sleep. Converging data from these literatures using food motivation and decision making fMRI paradigms suggest that the prefrontal and limbic brain systems might also play a role in the development and/or maintenance of NES. We use these data to support a new neural model of NES for future testing and validation.