Obesity and eating disorders

Relationship of estrogen synthesis capacity in the brain with obesity and self-control in men and women

Gonadal hormones are linked to mechanisms that govern appetitive behavior and its suppression. Estrogens are synthesized from androgens by the enzyme aromatase, highly expressed in the ovaries of reproductive-aged women and in the brains of men and women of all ages. We measured aromatase availability in the amygdala using positron emission tomography (PET) with the aromatase inhibitor [¹¹C]vorozole in a sample of 43 adult, normal-weight, overweight, or obese men and women. A subsample of 27 also completed personality measures to examine the relationship between aromatase and personality traits related to self-regulation and inhibitory control. Results indicated that aromatase availability in the amygdala was negatively associated with body mass index (BMI) (in kilograms per square meter) and positively correlated with scores of the personality trait constraint independent of sex or age. Individual variations in the brain's capacity to synthesize estrogen may influence the risk of obesity and self-control in men and women.

Words with weight: The construction of obesity in eating disorders research

In current public health discourse, obesity is conceptualized as a disease epidemic, with treatment being weight loss. The pursuit of weight loss as a treatment for the “disease” of obesity is in direct contradiction to the history of research in eating disorders, which has demonstrated the risks for the development of eating disorders. In this study, we critically examined the eating disorder literature to explore this contradiction. We analyzed 30 of the top-cited articles in the eating disorder literature between 1994 and 2011, asking: how is the concept of obesity examined in eating disorder research? We identified tensions related to body mass index and the perceived associated risks of lower or higher body mass index, assumptions of the “causes” of fatness (i.e. overeating and inactivity), and the anti-diet voice challenging the prescription of dieting for those in fat bodies. In our analysis, we highlight the problematics of, for instance, prescribing a body mass index range of 20–24 in eating disorder recovery, how many studies in eating disorders do not problematize the presumption that a higher body mass index is necessarily associated with ill health, and a lack of cultural sensitivity and acknowledgment of intersectional spaces of belonging. We discuss these themes in the context of biomedical discourses of obesity contributing to the cultural thin ideal. We argue that biomedical discourses on obesity contribute to the thin ideal nuanced against discourses of healthism that permeate our society. Rather than an ideal of emaciation, it is an ideal of a healthy, productive person, often constructed as morally superior. The moral panic around obesity is evident throughout the eating disorder literature, which is a concern given that we would hope that the aim of eating disorder treatment would be to promote wellness for all—not only those who are thin.

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

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

Psychosocial Characteristics and Gestational Weight Change among Overweight, African American Pregnant Women

Objectives. To describe psychosocial factors identified as contributors of weight gain in the general population and to examine the relationship between these factors and gestational weight gain among low socioeconomic status, African American, overweight pregnant women. Methods. African American women (n = 120) with a pregravid body mass index ≥25 kg/m² completed measures of eating, sleep, and depressed mood between 14 and 24 weeks of gestation. Weight was tracked. Descriptive statistics, correlations, and linear regression modeling were used to characterize the sample and examine predictors of gestational weight gain. Results. Four percent screened positive for night eating syndrome, with 32% consuming at least 25% of their daily caloric intake after dinner (evening hyperphagia). None met criteria for binge eating disorder; 4% reported occasional binge episodes. Cognitive restraint over eating was low. Participants slept 7.1 (SD = 1.9) h per night and reported 4.3 (SD = 3.6) awakenings per week; 18% reported some level of depressed mood. Night and binge eating were related to each other, sleep quality, and depressed mood. Eating due to cravings was the only psychosocial variable to predict gestational weight gain. Conclusions. Depressed mood, night eating, and nighttime awakenings were common in this cohort, while cognitive restraint over eating was low. Most psychosocial variables were not predictive of excess gestational weight gain.

Lifestyle modifications and surgical options in the treatment of patients with obesity and type 2 diabetes mellitus

This article reviews recent developments in the behavioral and surgical treatment of obesity and type 2 diabetes mellitus (T2DM). Randomized controlled trials of comprehensive lifestyle-modification programs, which include dietary interventions, physical activity, and behavioral therapy, have shown weight losses of 7% to 10% of initial body weight within 4 to 6 months after treatment. These programs also reduce the likelihood of developing T2DM by 58% for individuals with impaired glucose tolerance. Long-term maintenance of these improvements requires continued implementation of the program diet, physical activity, and self-regulatory behaviors. This can be successfully facilitated by continued patient-provider contact, which is frequently delivered by phone, mail, email, or online. However, these benefits may have less impact on those with extreme obesity or more significant health problems. For these individuals, bariatric surgery may be a more appropriate treatment. Bariatric surgical procedures induce mean weight losses of 15% to 30% of initial body weight (depending on the procedure) within 2 years after surgery, as well as a 45% to 95% rate of diabetes remission. Familiarity with these developments can help physicians and patients to determine which combinations of behavioral, medical, and surgical interventions are appropriate for the treatment of obesity and T2DM.

Gastrointestinal symptoms and obesity: a meta-analysis

Weight loss is a recognized alarm symptom for organic gastrointestinal (GI) disease, yet the association between obesity and specific GI symptoms remains poorly described. A meta-analysis was conducted to determine which GI symptoms predominate among obese individuals. A search of the literature using the databases MEDLINE, EMBASE PubMed and Current Contents (1950 - November 2011) was conducted. All studies assessing GI symptoms and increasing body mass index (BMI)/obesity were included. English and non-English articles were searched. A random effect model of the studies was undertaken. Overall, significant associations between GI symptoms and increasing BMI were found for upper abdominal pain (odds ratio [OR] = 2.65, 95% confidence interval [CI]: 1.23-5.72), gastroesophageal reflux (OR = 1.89, 95% CI: 1.70-2.09), diarrhoea (OR = 1.45, 95% CI: 1.26-1.64), chest pain/heartburn (OR = 1.74, 95% CI: 1.49-2.04), vomiting (OR = 1.76, 95% CI: 1.28-2.41), retching (OR = 1.33, 95% CI: 1.01-1.74) and incomplete evacuation (OR = 1.32, 95% CI: 1.03-1.71). However, no significant associations were found for all abdominal pain, lower abdominal pain, bloating, constipation/hard stools, fecal incontinence, nausea and anal blockage. Several key GI symptoms are associated with increasing BMI and obesity. In addition, there were a number of other GI symptoms that had no relationship with obesity. A greater knowledge of the GI symptoms associated with obesity along with the physiology will be important in the clinical management of these patients.

Impact of eating disorders and psychological distress on the quality of life of obese people

OBJECTIVE

Quality of life (QoL) is impaired in obesity, but the roles of eating behavior and psychological distress need to be more documented.

METHODS

One hundred thirty consecutive obese patients seeking medical care filled out questionnaires evaluating QoL, the presence of an eating disorder (ED), levels of anxiety and depression, and perception of body image.

RESULTS

Global QoL was poor in 16.4% and intermediate in 61.8% of the patients. EDs were present in 58% of patients who were more (P = 0.05) overweight; 24.2% of patients had binging. EDs impaired significantly the global and specific dimensions of QoL; binging impaired physical and sexual QoLs (both P < 0.02). Anxiety and depression were found in 73.6% and 50.4% of patients, respectively; depression was more frequent in women (P = 0.007) and in patients with EDs. Anxiety and/or depression impaired global (P < 0.001) and specific dimensions of QoL. Body shape concern was marked in 86.4% of women and associated with poor global (P < 0.001) and specific QoL, and with anxiety and depression.

CONCLUSION

The impairment of QoL in obese patients is increased by the presence of an ED, anxiety, and/or depression and marked body shape concern. These psychological factors should be assessed more carefully and taken into account in global strategies aiming to improve the well-being of obese patients.

Medical and behavioral evaluation of patients with obesity

Obesity may be the most significant medical problem that health care providers will face over the coming decades. Physicians must aggressively address this chronic disease, providing both preventive and therapeutic care. Since this topic has not been traditionally taught in medical school or residency training, physicians and other health providers will need to acquire the knowledge, skills, and attitudes necessary to be effective obesity care providers. Performing a detailed initial assessment, including an obesity focused history, physical examination, and selected laboratory and diagnostic tests is fundamental to the process of care.

Ghrelin receptor signaling: a promising therapeutic target for metabolic syndrome and cognitive dysfunction

The neuroendocrine hormone ghrelin is an octanoylated 28-residue peptide that exerts numerous physiological functions. Ghrelin exerts its effects on the body mainly through a highly conserved G protein-coupled receptor known as the growth hormone secretagagogue receptor subtype 1a (GHS-R1a). Ghrelin and GSH-R1a are widely expressed in both peripheral and central tissues/organs, and ghrelin signaling plays a critical role in maintaining energy balance and neuronal health. The multiple orexigenic effects of ghrelin and its receptor have been studied in great detail, and GHS-R1a-mediated ghrelin signaling has long been a promising target for the treatment of metabolic disorders, such as obesity. In addition to its well-characterized metabolic effects, there is also mounting evidence that ghrelin-mediated GHS-R1a signaling exerts neuroprotective effects on the brain. In this review, we will summarize some of the effects of ghrelin-mediated GSH-R1a signaling on peripheral energy balance and cognitive function. We will also discuss the potential pharmacotherapeutic role of GSH-R1a-mediated ghrelin signaling for the treatment of complex neuroendocrine disorders.

Prevalence and epidemiology of gastrointestinal symptoms among normal weight, overweight, obese and extremely obese individuals

Until recently, the epidemiology of gastrointestinal (GI) symptoms had not been adequately studied in relation to increasing body mass index. To date there are only a few studies in the literature, and thus the relationship between obesity and specific GI symptoms is poorly understood. Future studies that incorporate different ethnicities from varied geographic locations are urgently required. A greater understanding of how GI symptoms are related to obesity and the physiology will be important in the clinical management of these patients.

Association studies on ghrelin and ghrelin receptor gene polymorphisms with obesity

Ghrelin exerts a stimulatory effect on appetite and regulates energy homeostasis. Ghrelin gene variants have been shown to be associated with metabolic traits, although there is evidence suggesting linkage and association with obesity and the ghrelin receptor (GHSR). We hypothesized that these genes are good candidates for susceptibility to obesity. Direct sequencing identified 12 ghrelin single-nucleotide polymorphisms (SNPs) and 8 GHSR SNPs. The 10 common SNPs were genotyped in 1,275 obese subjects and in 1,059 subjects from a general population cohort of European origin. In the obesity case-control study, the GHSR SNP rs572169 was found to be associated with obesity (P = 0.007 in additive model, P = 0.001 in dominant model, odds ratio (OR) 1.73, 95% confidence interval (1.23-2.44)). The ghrelin variant, g.A265T (rs4684677), showed an association with obesity (P = 0.009, BMI adjusted for age and sex) in obese families. The ghrelin variant, g.A-604G (rs27647), showed an association with insulin levels at 2-h post-oral glucose tolerance test (OGTT) (P = 0.009) in obese families. We found an association between the eating behavior "overeating" and the GHSR SNP rs2232169 (P = 0.02) in obese subjects. However, none of these associations remained significant when corrected for multiple comparisons. Replication of the nominal associations with obesity could not be confirmed in a German genome-wide association (GWA) study for rs4684677 and rs572169 polymorphisms. Our data suggest that common polymorphisms in ghrelin and its receptor genes are not major contributors to the development of polygenic obesity, although common variants may alter body weight and eating behavior and contribute to insulin resistance, in particular in the context of early-onset obesity.

The Night Eating Questionnaire (NEQ): psychometric properties of a measure of severity of the Night Eating Syndrome

The purpose of this study was to evaluate the Night Eating Questionnaire (NEQ) as a measure of severity of the Night Eating Syndrome (NES). The 14-item NEQ assesses the behavioral and psychological symptoms of NES. The NEQ was evaluated in three samples: 1980 persons who completed the NEQ on the Internet; 81 persons diagnosed with NES; and 194 bariatric surgery candidates. Study 1, using principal components analysis, generated four factors (nocturnal ingestions, evening hyperphagia, morning anorexia, and mood/sleep) and an acceptable alpha (.70). Confirmatory factor analysis suggested that 99% of covariation among factors is accounted for by a higher-order construct. Study 2 found convergent validity of the NEQ with additional measures of night eating, disordered eating, sleep, mood, and stress. Study 3 compared scores from obese bariatric surgery candidates with and without NES and found appropriate discriminant validity of the NEQ. The NEQ appears to be an efficient, valid measure of severity for NES.

Psychiatric considerations of the massive weight loss patient

As bariatric surgery for extreme obesity continues to grow in popularity, so does interest in postbariatric surgery body-contouring surgery. There is an extensive literature on the psychological characteristics of persons with extreme obesity who undergo bariatric surgery and the psychological changes that typically occur postoperatively. Far less, however, is known about the psychological aspects of body contouring following massive weight loss. This article reviews the psychosocial characteristics of individuals with extreme obesity who undergo bariatric surgery, as well as the changes in these traits that typically occur postoperatively. Because there have been few studies of the psychological aspects of patients who have lost massive amounts of weight, we use related literatures on the relationship between body image dissatisfaction and other plastic surgical procedures to identify the most relevant research and clinical issues for this unique patient population. Appropriate psychiatric screening and management of these patients is believed to play an important role in successful postoperative outcomes.

Is there a place for obesity in DSM-V?

OBJECTIVE

To revisit the merits and problems inherent in considering obesity, or some aspect of obesity, as a mental or behavioral disorder.

METHOD

The author suggests shifting the focus from the state of obesity to the process of nonhomeostatic overeating that results in obesity. Studies are reviewed that pertain to various models of nonnormative overeating including eating disorder models that stress the form of overeating, substance use disorder models focusing on its consequences, and affect regulation or stress response models focusing on its function.

RESULTS

Studies focusing on abnormal eating patterns, including binge eating and night eating suggest that such patterns may be related to the development of obesity. While the literature pertaining to substance use and other models of nonhomeostatic overeating is beginning to mount, current evidence is mostly preliminary and indirect.

CONCLUSION

An attempt to devise diagnostic criteria based on the above models raises multiple difficulties, since the phenomena central to each model are dimensional, common, and variably associated with distress or dysfunction. A detailed understanding of the neurobiological relationships among eating behavior, reward systems, and affect regulation systems will enable a more meaningful consideration of these models and will facilitate specific treatment for disorders of overeating.

Responses to weight loss treatment among obese individuals with and without BED: a matched-study meta-analysis

The moderating influence of binge eating status on obese individuals' responses to weight loss treatment was evaluated with a meta-analysis of 36 tests of weight loss treatment (n=792) that were matched to control key background variables. After controlling for pre-treatment weight, treatment produced more weight loss in samples of obese non-BED compared with obese BED participants. Weight loss treatment produced large posttreatment reductions in depression in both obese BED and non-BED samples. The results indicate that BED status moderated post-treatment weight loss among people in weight treatment programs. Obese BED (average weight loss=1.3 kg) samples lost negligible weight compared to obese non-BED (average weight loss=10.5 kg) samples. BED status did not moderate psychological responses to treatment: both BED and non-BED samples experienced large post-treatment reductions in depression. The clinical implications of these findings are discussed.

Psychosocial and behavioral status of patients undergoing bariatric surgery: what to expect before and after surgery

Extreme obesity, characterized by a body mass index (BMI) of 40 kg/m(2) or greater, is associated with significantly increased mortality, principally from cardiovascular disease, type 2 diabetes, and several cancers. It also is associated with an increased risk of psychosocial complications, including depression, eating disorders, and impaired quality of life. This article briefly examines the psychosocial status of extremely obese individuals who seek bariatric surgery and describes changes in functioning that can be expected with surgically induced weight loss. The article combines a review of the literature with clinical impressions gained from the more than 2500 candidates for bariatric surgery whom the authors have evaluated at the Hospital of the University of Pennsylvania.

The application of ecological momentary assessment to the study of night eating

OBJECTIVE

Night eating syndrome (NES) was first described in 1955 by Albert Stunkard and colleagues. NES consists of either overeating at night or waking up during the night and eating.

METHOD

In the current study we used ecological momentary assessment (EMA) to describe 14 self-defined night-eaters. The participants in the current study completed an EMA protocol of approximately two weeks.

RESULTS

We found that ratings of hunger appeared to be higher during night awakenings than in the evening. Also, both affect and arousal generally decreased throughout the day and were lowest during awakening episodes.

CONCLUSION

The current study adds interesting data in describing the experience of night-eating behavior with ecological momentary assessments from self-described night-eaters.

Night eating syndrome and binge eating disorder among persons seeking bariatric surgery: prevalence and related features

OBJECTIVE

To assess the prevalence of night eating syndrome (NES) and binge eating disorder (BED) and their related behavioral and psychological correlates in persons who sought bariatric surgery.

RESEARCH METHODS AND PROCEDURES

A consecutive series of 215 persons with extreme obesity (82% women, 70% European American) completed the Weight and Lifestyle Inventory and a semistructured interview as part of a pre-surgery behavioral/psychological assessment. Diagnoses for NES and BED were based on graded diagnostic criteria.

RESULTS

Percentages of participants who met diagnostic criteria for NES by interview were 1.9% for the strictest definition and 8.9% across all definitions of NES. After interview, full DSM-TR criteria for BED were met by 4.2%; an additional 1.4% reported binge eating at least once per week. Self-reported prevalence of NES and BED were higher. Those with NES or BED had significantly more symptoms of depression and a greater history of psychological complications than the remaining sample.

DISCUSSION

The prevalence rates of NES and BED among this population of bariatric surgery candidates were lower than expected based on previous reports. Findings and hypotheses regarding lowered prevalence rates are discussed.

Behavioral assessment of candidates for bariatric surgery: a patient-oriented approach

This paper discusses the behavioral evaluation of patients who seek bariatric surgery and the psychosocial complications most frequently observed in these individuals. The effects of such complications on surgical outcome are briefly examined, as is the challenge of predicting therapeutic response on the basis of preoperative variables. The paper concludes with a description of the goals and methods of a behavioral assessment used at the University of Pennsylvania. This evaluation includes the use of the Weight and Lifestyle Inventory, a questionnaire that guides our interview with patients.