On the relation of attempting to lose weight, restraint, and binge eating in outpatients with binge eating disorder

A systematic review and meta-analysis of animal models of binge eating - Part 1: Definitions and food/drink intake outcomes

Binge eating involves consuming excessive amounts of food within a discrete period of time and is associated with significant impairments in binge-eating disorder and bulimia nervosa. While research on clinical binge eating has provided valuable aetiological insights, animal models allow for closer examination of environmental, biological, and developmental risk factors. Numerous animal models of binge eating exist and differ widely in operational definitions of bingeing, animal characteristics and methodological parameters. The current review aimed to synthesise the available published evidence on these models. A systematic review of binge definitions in 170 articles found most studies displayed good face validity. Meta-analyses on 150 articles confirmed that the amount of food or drink consumed by animals under binge conditions was larger than that of non-binge conditions across many protocols. The meta-regression revealed species, strain, and sex moderated binge effect size, with the largest effect observed in studies with female animals and mice. Risk of bias assessment identified that improved reporting of allocation, baseline characteristics and outcome assessment is required in future studies.

Examining heterogeneity of binge-eating disorder using latent class analysis

There is significant variability in the type and severity of symptoms reported by individuals diagnosed with binge-eating disorder (BED). Using latent class analysis (LCA), the current study aimed to investigate potential sources of heterogeneity among individuals with BED. Participants were 775 treatment-seeking adults with DSM-IV-defined BED. Doctoral research clinicians reliably assessed participants for BED and associated eating-disorder psychopathology using the Structured Clinical Interview for DSM-IV Disorders and the Eating Disorder Examination (EDE) interview, measured weight and height, and participants completed a battery of self-report measures. Based on fit statistics and class interpretability, a 2-class model yielded the best overall fit to the data. The two classes were most distinct with respect to differences in body image concerns, distress about binge-eating, and depressive symptomology. Number of binge episodes were significantly different between classes, though the effect was much smaller. Body mass index was not a significant covariate in the majority of models. The results show that many of the features currently used to define BED (e.g., binge-eating frequency) are not helpful in explaining heterogeneity among individuals with BED. Instead, body image disturbances, which are not currently included as a part of the diagnostic classification system, appear to differentiate distinct subgroups of individuals with BED. Future research examining subgroups based on body image could be integral to resolving ongoing conflicting evidence related to the etiology and maintenance of BED.

Separating the Signal from the Noise: How Psychiatric Diagnoses Can Help Discern Food Addiction from Dietary Restraint

Converging evidence from both animal and human studies have implicated hedonic eating as a driver of both binge eating and obesity. The construct of food addiction has been used to capture pathological eating across clinical and non-clinical populations. There is an ongoing debate regarding the value of a food addiction "diagnosis" among those with eating disorders such as anorexia nervosa binge/purge-type, bulimia nervosa, and binge eating disorder. Much of the food addiction research in eating disorder populations has failed to account for dietary restraint, which can increase addiction-like eating behaviors and may even lead to false positives. Some have argued that the concept of food addiction does more harm than good by encouraging restrictive approaches to eating. Others have shown that a better understanding of the food addiction model can reduce stigma associated with obesity. What is lacking in the literature is a description of a more comprehensive approach to the assessment of food addiction. This should include consideration of dietary restraint, and the presence of symptoms of other psychiatric disorders (substance use, posttraumatic stress, depressive, anxiety, attention deficit hyperactivity) to guide treatments including nutrition interventions. The purpose of this review is to help clinicians identify the symptoms of food addiction (true positives, or "the signal") from the more classic eating pathology (true negatives, or "restraint") that can potentially elevate food addiction scores (false positives, or "the noise"). Three clinical vignettes are presented, designed to aid with the assessment process, case conceptualization, and treatment strategies. The review summarizes logical steps that clinicians can take to contextualize elevated food addiction scores, even when the use of validated research instruments is not practical.

Dietary restraint and weight loss as risk factors for eating pathology

Measures of dietary restraint do not consistently predict caloric restriction, and these scales appear inadequate for differentiating between healthy and risky restraint in individuals. The current study examined the relationship between self-reported dietary restraint, recent weight loss, body mass index (BMI), and eating pathology in a college sample to determine if dietary restraint coupled with caloric restriction would prove to be a more sensitive marker of eating disorder risk than restraint alone. Participants (N=245) completed a series of measures evaluating dietary restraint, recent weight loss, and eating habits. Results suggested that dietary restraint related most consistently to eating pathology, with more nuanced results for women regarding the relations between dietary restraint, recent weight loss, and BMI. Findings provided further evidence that dietary restraint and weight loss may relate to eating pathology through independent pathways. In addition, recent weight loss may be a relevant risk factor for women at lower current BMI.

Associations of negative affect and eating behaviour in obese women with and without binge eating disorder

The present study was planned to investigate differences in psychopathological features, eating behaviour and eating habits between obese women with and without BED. It also aimed to identify specific relationships between affective symptoms and eating behaviour in obese women with BED. Eighty-four obese women were studied (40 with BED, 44 non-BED). Psychiatric comorbidities were assessed with the structured diagnostic interview for DSM-IV (SCID). Depressive symptoms were measured with the Beck Depression Inventory (BDI) and anxiety with the state-trait anxiety inventory (STAI). Eating habits (emotional and restrained eating) were assessed by the Dutch eating behaviour questionnaire (DEBQ). Food diaries were used for assessing naturalistic eating behaviour (food intake) and mood before and after food intake. BED subjects exhibited higher levels of comorbidity (in particular mood disorders, anxiety disorders and substance-related disorders), higher depressive symptoms, trait anxiety, external and emotional eating scores than non-BED subjects. Regression analyses revealed that anxiety and emotional eating were significant predictors for BED status. In the BED group, depressive symptoms were significantly related to emotional eating and food intake and negatively related to restraint. Anxiety was significantly related to emotional eating. In general, food intake significantly enhanced mood. Mood was worse on the days with self-reported binge eating episodes than on nonbinge days. These results are discussed with regard to aetiological models for BED and for BED being a distinct diagnostic category separate from obesity.

Decision-making impairments in women with binge eating disorder

Even though eating is frequently driven by overindulgence and reward rather than by energy balance, few studies so far have analyzed decision-making processes and disturbances in feedback processing in women with binge eating disorder (BED). In an experimental study, 17 women with BED (DSM-IV) and 18 overweight healthy controls (HC) were compared in the game of dice task (GDT). This task assesses decision-making under risk with explicit rules for gains and losses. Additionally, differences in dispositional activation of the behavior inhibition and behavior approach system as well as cognitive flexibility were measured. Main results revealed that women with BED make risky decisions significantly more often than HC. Moreover, they show impaired capacities to advantageously utilize feedback processing. Even though these deficits were not related to disease-specific variables, they may be important for the daily decision-making behavior of women with BED, thus being relevant as a maintenance factor for the disorder.

Relationship of eating behavior to long-term weight change and body mass index: the Healthy Twin study

This study examined the relationships of the Dutch Eating Behavior Questionnaire (DEBQ) subscales with weight change and with current body mass index (BMI). A total of 1576 adult twins and their families (578 Korean men, 998 Korean women, age 44.5+/-12.9 years) participating in the Healthy Twin study completed a survey that included the DEBQ, self-reported weight at 20 years old and intentionally lost weight over the past 4 years. Their anthropometric measurements were taken. Using the general linear models, restrained eating was positively associated with weight gain from 20 years old to current age [beta (B) =1.01, standard error (SE)=0.27, p<0.001], and with current BMI (B=0.33, SE=0.09, p<0.001) after adjusting for demographics, health-related behaviors, energy intake, and emotional and external eating. Likewise, emotional eating was positively associated with weight gain (B=0.83, SE=0.28, p<0.001), and with current BMI (B=0.35, SE=0.10, p=0.003) after adjusting those factors, and restrained and external eating. However, external eating was not associated with both outcomes. In conclusion, high restrained eating or emotional eating may be indicators for long-term weight gain and high BMI in Korean twins and their families.

Recurrent binge eating (RBE) and its characteristics in a sample of young women in Germany

OBJECTIVE

To examine the characteristics of recurrent binge eating (RBE) in a non-treatment-seeking sample from the general population. RBE individuals are described in terms of socio-economic status, general psychopathology, and comorbidity rates of mental disorders.

METHOD

Participants were 1877 German females aged 18-24 years from a population-based epidemiological study.

RESULTS/DISCUSSION

The point prevalence of RBE in our sample was 0.9% (N = 17). Compared to healthy women, subjects with RBE suffered more often from comorbid mental disorders and also exhibited more general psychopathology: They were similar to women with other mental disorders and other eating disorders (EDs). RBE seems to be a syndrome of clinical significance itself and might be an important risk factor for the development of further EDs, especially binge eating disorder (BED) and other mental disorders.

The Eating Inventory, body adiposity and prevalence of diseases in a quota sample of Czech adults

OBJECTIVE

To study the relationships between the Eating Inventory (EI) factors (restraint, disinhibition and hunger), body adiposity and prevalence of selected diseases in a quota sample of Czech adults.

SUBJECTS AND METHODS

The sample included 1429 men and 1624 women who were interviewed individually by trained investigators. The sample was quota representative--for gender, age, size of residential location, region and socioeconomic status in Czech adults. Anthropometric data, socioeconomic and lifestyle information were obtained. Subjects filled out the EI questionnaire. Physicians reported about subjects' morbidity.

RESULTS

Backward stepwise regression analysis revealed that restraint and disinhibition were significant predictors of body mass index (BMI) along with gender, age, parental obesity, weight loss attempts, present dieting and educational level. The same factors plus income predicted the waist circumference. BMI and waist circumference were negatively related to restraint but positively to disinhibition. According to logistic regression analysis restraint and disinhibition were significantly associated with hypertension, cardiovascular diseases and hyperlipidaemia. Diabetes was significantly related to restraint and hunger scores. The observed association between EI factors and diseases remained significant even when BMI and age were taken into account.

CONCLUSION

As shown in earlier studies, disinhibition was positively and restraint negatively associated with BMI and waist circumference. For the first time, factors of the EI were also identified as significant predictors of diseases characterizing the metabolic syndrome.

Risk factors and patterns of onset in binge eating disorder

OBJECTIVE

The current study examined risk factors in women with binge eating disorder (BED) who began binging before dieting (binge-first [BF]) compared with women with BED who began dieting before binging (diet-first [DF]). It further aimed to replicate findings regarding eating disorder and general psychopathology among BF versus DF subtypes.

METHOD

One hundred fifty-five women with BED completed the Oxford Risk Factor Interview to retrospectively assess risk factors occurring before eating disturbance onset. Clinical interview assessed eating disorder and general psychopathology.

RESULTS

Overall, no significant differences in risk factors emerged between the groups. The BF group had a significantly earlier onset of BED than the DF group. In contradistinction to previous studies, the DF group endorsed more eating disorder psychopathology and lifetime diagnosis of any substance use disorder.

CONCLUSION

Limited support was seen for different risk factors in BF versus DF women, suggesting similar etiologic pathways in both subtypes.

Influence of heredity on dietary restraint, disinhibition, and perceived hunger in humans

OBJECTIVE

Dietary restraint, disinhibition, and perceived hunger have been shown to affect food intake and body weight and are thought to be risk factors for eating disorders, but little is known about their origins. We investigated the influence of heredity, shared (familial) environment, and individual environment on dietary restraint disinhibition, perceived hunger and their relation to body size and food intake.

METHODS

Scores on the Three Factor Eating Questionnaire and the Restraint Scale in addition to height, weight, body mass index, and 7-d diary reported nutrient intakes were obtained from 39 identical, 60 fraternal same-sex, and 50 fraternal opposite-sex adult twin pairs who were living independently. Linear structural modeling was applied to investigate the nature and degree of genetic and environmental influences.

RESULTS

Analysis showed significant genetic and individual environmental, but not shared (familial) environmental, influences on cognitive restraint, perceived hunger, and Restraint Scale scores, with genes accounting for 44%, 24%, and 58% of the variance, respectively. In contrast, disinhibition was found to be significantly influenced by the shared (familial) environment, accounting for 40% of the variance. Further analysis showed that cognitive restraint and perceived hunger heritabilities could not be accounted for by significant heritabilities of body weight, height, or body mass index. In contrast, the heritability of Restraint Scale scores was found to be related to body size. Cognitive restraint was negatively correlated with nutrient intake, and differences in cognitive restraint were found to be related to differences in the body sizes of identical twin pairs.

CONCLUSIONS

Dietary restraint appears to be another component in a package of genetically determined physiologic, sociocultural, and psychological processes that regulate energy balance, whereas dietary disinhibition may be the intermediary between upbringing and the development of overweight and/or eating disorders.

Psychobehavioral and nutritional predictors of weight loss in obese women treated with sibutramine

OBJECTIVE

To reveal whether baseline body mass index (BMI), and psychobehavioral and nutritional markers were significant predictors of the change in BMI observed after 4 and 12 months in obese women enrolled in a weight reduction program, including low-energy diet, increased physical activity, cognitive behavior therapy and sibutramine. The impact of changes in psychobehavioral and nutritional markers observed after 4 and 12 months of treatment on BMI changes was also investigated.

DESIGN

During a double-blind placebo-controlled 4-month period, subjects received either sibutramine (10 mg/day) or placebo. Then, an open phase with sibutramine administered to all patients continued until month 12.

SUBJECTS

In total, 80 obese women (age: 43.9+/-10.6 y, BMI: 36.7+/-4.8 kg/m(2)).

MEASUREMENTS

The dependent variable was change in BMI while baseline BMI, mode of treatment, the Beck depression score, the three items (dietary restraint, disinhibition and perceived hunger) of the Eating Inventory (EI), energy and macronutrient intakes were independent variables. At 1-week dietary records were analyzed using a computer software for assessing energy and macronutrient intake.

RESULTS

Multiple regression analysis revealed that the BMI loss at month 4 was significantly influenced by mode of treatment and initial BMI, whereas a borderline negative relationship was observed with the baseline restraint score. Baseline BMI, depression score, restraint score and total energy intake predicted weight loss at month 12. These predictive variables accounted for 43.8% of the variance in BMI loss at 12 months. When relationships between the BMI loss and changes in all included psychobehavioral and nutritional parameters were considered after 12 months of treatment, a drop in the disinhibition score of the EI appeared the only significant factor affecting the BMI decrease.

CONCLUSIONS

Our results suggest that psychobehavioral and nutritional characteristics can be used as predictors of weight loss in response to a comprehensive weight management program including pharmacological treatment with sibutramine.

When identical twins differ: an analysis of intrapair differences in the spontaneous eating behavior and attitudes of free-living monozygotic twins

Heredity has been shown to have major influences on the body size and ingestive behaviors of humans. However, environment is also important as evidenced by the fact that even identical twins can differ in body size and nutrient intake. To investigate the relative influence of heredity and environment, differences between the body size and food intake of 110 identical adult twin pairs who were living independently were studied with a 7-day diet diary technique. Differences within twin pairs (intrapair differences) in diet density were related to differences in daily intakes, but not with body size differences. On the other hand, cognitive restraint and disinhibition were related to intrapair differences in body size, but not intake. The fact that there are important environmental and psychological factors that influence intake and body size, even in individuals who have identical genotypes, supports the recently proposed general model of intake regulation [de Castro JM, Plunkett S. A general model of intake regulation. Neurosci. Biobehav. Rev. 26 (5) (2002) 581-595].

Characteristics of morbidly obese patients before gastric bypass surgery

The prevalence of binge eating disorder (BED) was assessed in a sample of 110 morbidly obese presurgery patients by means of self-report (Questionnaire on Eating and Weight Patterns [QEWP]). Subsequently, patients with (n = 19, 17.3%) and without BED (n = 91, 82.7%) were compared on several eating-related and general psychopathological instruments, as well as an obesity-specific health-related quality-of-life measure. Patients with BED exhibited higher scores than non-BED patients on most of the subscales of two questionnaires measuring eating behavior and attitudes towards eating, shape, and weight (Three Factor Eating Questionnaire [TFEQ], Eating Disorders Examination-questionnaire version [EDE-Q4]) with the exception of the respective restraint subscales. The two groups also differed significantly on the disease-specific quality-of-life measure (Impact of Quality of Life Questionnaire-Lite [IWQOL-Lite]). No differences were found for measures of severity of depressive symptoms (Inventory of Depressive Symptoms [IDS]) and impairment of self-esteem (Rosenberg Self-Esteem Questionnaire [RSE]). Our findings replicate the results of other studies comparing patients with and without BED in samples with different degrees of obesity and extend the results to an obesity-specific quality-of-life measure. Further research needs to investigate the short- and long-term impact of presurgery BED on surgery outcome, as well as the impact of surgery on binge eating and eating-related psychopathology.

Psychological and behavioral correlates of baseline BMI in the diabetes prevention program (DPP)

OBJECTIVE

To determine psychological and behavioral correlates of baseline BMI in the Diabetes Prevention Program (DPP).

RESEARCH DESIGN AND METHODS

Of 1,079 DPP lifestyle intervention participants, 274 completed validated questionnaires at baseline assessing weight loss history, stage of change, self-efficacy, dietary restraint, emotional eating, binge eating, perceived stress, depression, and anxiety.

RESULTS

The mean age of subjects was 52.5 years, 65% were women, and their mean BMI was 33.9 kg/m(2). Higher BMI correlated with more frequent weight cycling (r = 0.50, P < 0.0001) and efforts at weight loss (r = 0.34, P < 0.0001); younger age when first overweight (r = -0.42, P < 0.0001); lower exercise efficacy (r = -0.15, P = 0.015); lower weight loss efficacy (r = -0.21, P < 0.001); a less advanced stage of change for weight loss (r = -0.12, P = 0.04); more perceived stress (r = 0.14, P = 0.02); emotional eating (r = 0.19, P = 0.001); poor dietary restraint (r = -0.14, P = 0.02); binge eating frequency (r = 0.18, P = 0.004) and severity (r = 0.30, P < 0.0001); feeling deprived, angry, or upset while dieting (r = 0.27, P </= 0.0001); and food cravings while dieting (r = 0.31, P < 0.0001). Correlations did not differ as a function of sex; however, correlations of BMI with anxiety and low-fat diet and weight loss self-efficacy differed as a function of ethnicity. In multivariate models, binge eating severity, poor dietary restraint, and food craving were independent correlates of baseline BMI.

CONCLUSIONS

Many psychological and behavioral factors are associated with higher BMI in this ethnically diverse group of men and women. Whether strategies that help patients increase levels of dietary restraint and reduce binge eating and food craving lead to long-term weight loss maintenance needs longitudinal study.