A Cross-Sectional Study of Evening Hyperphagia and Nocturnal Ingestion: Core Constituents of Night Eating Syndrome with Different Background Factors.

This web-based cross-sectional survey aimed to elucidate the differences between the two core symptoms of night eating syndrome (NES): evening hyperphagia and nocturnal ingestion in the general Japanese population aged 16-79 years. Participants who consumed at least 25% of daily calories after dinner were defined as having evening hyperphagia. Those who consumed food after sleep initiation at least twice a week were determined to have nocturnal ingestion. Of the 8348 participants, 119 (1.5%) were categorized in the evening hyperphagia group, 208 (2.6%) in the nocturnal ingestion group, and 8024 in the non-NES group. Participants with evening hyperphagia and nocturnal ingestion had significantly higher anxiety scores (p < 0.05 and p < 0.001, respectively) and depression (p < 0.001 for both) than those without NES. Multiple logistic regression analysis revealed that evening hyperphagia was significantly and independently associated with higher body mass index, shorter sleep duration, later sleep-wake schedule, and higher insomnia score, while nocturnal ingestion was significantly and independently associated with younger age, smoking habit, living alone, earlier sleep-wake schedule, and higher insomnia score. Sleep duration and sleep-wake schedule characteristics in the two groups were opposite, suggesting differences in the sleep pathophysiology mechanisms.

Night Eating Syndrome, circadian rhythms and seasonality: a study in a population of Italian university students.

PURPOSE: The aim of this research was to assess the prevalence of Night Eating Syndrome (NES) in a university student population and to clear up the relationship between NES, depression and chronotype. The relation between NES and seasonality was also investigated. METHODS: The data were collected from a sample of 1136 students of the L'Aquila University, Italy. All subjects were invited to answer to the Sociodemographic Information Form and to take a self-report battery composed by four questionnaires: the Night Eating Questionnaire (NEQ), the Morningness Eveningness Questionnaire (MEQ), the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Beck Depression Inventory (BDI). RESULTS: The 5.3% of our population (60 subjects) reached the criteria for NES. The distribution of chronotypes in the sample was: Morning Type 15.3%, Intermediate 64.3% and Evening Type 20.4%. The 36.7% of the participants reaching the criteria for NES, obtained low scores on the MEQ. The data indicated that NEQ and MEQ scores are significantly inversely correlated (r=-.22; p<.01, two-tailed test). The 3.6% of our population (41 subjects) reached the criteria for Seasonal Affective Disorder (SAD) and 10.7% for subclinical SAD (121 subjects). Furthermore, the 11.7% of subjects with NES presented SAD and the 5% presented Subclinical SAD. The data demonstrated that NES and Global Seasonality Score (GSS) are significantly associated (r=.22; p<0.01, two-tailed test). CONCLUSIONS: The main finding of this study is the strong relation between NES and eveningness dimension. Our results help to clear up the literature debate about the role of eveningness dimension in the night eating, suggesting that subjects with NES present a circadian delay, not only in the food intake, but in the entire functioning. At the best of one knowledge this study is the first one to examine the relationship between NES and seasonality. This research found preliminary evidence that, similarly to the findings of previous studies in subjects with Bulimia Nervosa (BN) and Binge Eating Disorder (BED), night eating symptoms may vary significantly across the seasons; subjects with NES experience seasonal variation in their mood and in their eating patterns.

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.

Brain-Behavior-Immune Interaction: Serum Cytokines and Growth Factors in Patients with Eating Disorders at Extremes of the Body Mass Index (BMI) Spectrum.

Alterations of the immune system are known in eating disorders (EDs), however the importance of cytokine balance in this context has not been clarified. We compared cytokines and growth factors at opposite ends of BMI ranges, in 90 patients classified in relation to BMI, depressive and EDs comorbidities. Serum concentrations of interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were determined by a biochip analyzer (Randox Labs). Differences were calculated through ANOVA. Possible predictors of higher cytokine levels were evaluated through regression analysis. IL-1α, IL-10, EGF, and IFN-γ were altered individuals with anorexia nervosa (AN) and binge eating disorder (BED). Night-eating was associated with IL-8 and EGF levels, IL-10 concentrations with post-dinner eating and negatively with sweet-eating, long fasting with higher IFN-γ levels. IL-2 increase was not linked to EDs, but to the interaction of depression and BMI. Altogether, for the first time, IL-1α, IL-10, EGF, and IFN-γ were shown to differ between AN and HCs, and between AN and individuals with obesity with or without BED. Only IL-2 was influenced by depression. Dysfunctional eating behaviors predicted abnormal concentrations of IL-10, EGF, IL-8 and IFN-γ.

Visual Attention to Pictorial Food Stimuli in Individuals With Night Eating Syndrome: An Eye-Tracking Study.

Night eating syndrome (NES) is characterized by excessive evening and/or nocturnal eating episodes. Studies indicate an attentional bias towards food in other eating disorders. For NES, however, evidence of attentional food processing is lacking. Attention towards food and non-food stimuli was compared using eye-tracking in 19 participants with NES and 19 matched controls without eating disorders during a free exploration paradigm and a visual search task. In the free exploration paradigm, groups did not differ in initial fixation position or gaze duration. However, a significant orienting bias to food compared to non-food was found within the NES group, but not in controls. A significant attentional maintenance bias to non-food compared to food was found in both groups. Detection times did not differ between groups in the search task. Only in NES, attention to and faster detection of non-food stimuli were related to higher BMI and more evening eating episodes. The results might indicate an attentional approach-avoidance pattern towards food in NES. However, further studies should clarify the implications of attentional mechanisms for the etiology and maintenance of NES.

Night eating among veterans with obesity.

The obesity rate is higher among veterans than the general population, yet few studies have examined their eating behaviors, and none have examined the presence of night eating and related comorbidities. This study examines night eating syndrome (NES) among veterans seeking weight management treatment, and relationships between NES and weight, insomnia, disordered eating, and psychological variables. The sample consisted of 110 veterans referred to a weight management program at VA Connecticut Healthcare System. More than one out of ten veterans screened positive for NES, and one-third screened positive for insomnia. Most individuals screening positive for NES also screened positive for insomnia. Night eating was associated with higher BMI, and with higher scores on measures of binge eating, emotional overeating, and eating disorder symptomatology. Veterans screening positive for NES were also significantly more likely to screen positive for depression and PTSD. When controlling for insomnia, only the relationships between night eating and binge and emotional eating remained significant. Those screening positive for PTSD were more likely to endorse needing to eat to return to sleep. Findings suggest that both NES and insomnia are common among veterans seeking weight management services, and that NES is a marker for additional disordered eating behavior, specifically binge eating and overeating in response to emotions. Additional studies are needed to further delineate the relationships among NES, insomnia, and psychological variables, as well as to examine whether specifically addressing NES within behavioral weight management interventions can improve weight outcomes and problematic eating behaviors.

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.