Implicit cognitive processes in binge-eating disorder and obesity

Self-referential processing in anorexia nervosa

OBJECTIVE

Anorexia nervosa (AN) is a serious psychiatric illness associated with significant medical and psychiatric comorbidity and impairment. Theoretical models of AN and self-report studies suggest that negative self-evaluation (i.e., low self-esteem) is related to the development and maintenance of AN. The goal of this study was to extend findings from self-report methodology using a neurocognitive task that probes self-evaluation implicitly and explicitly.

METHOD

We compared female adolescent and adult patients with AN (n = 35) and healthy controls (HC, n = 38) on explicit (i.e., endorsement of words as self-relevant), implicit (recall, recognition, reaction time), and composite (i.e., valence index, bias score, drift rates) indices of self-evaluation. We applied a drift-diffusion model to compute the drift rates, reflecting participants' decision-making process as to whether words were self-relevant. The association between self-evaluation indices and eating disorder severity was examined.

RESULTS

There were significant Group × Condition interaction effects for all explicit and implicit measures (all p's ≤ .01), where the AN group endorsed, recalled, and recognized more negative relative to positive words than HC. The AN group had more negative valence index and bias scores, and slower drift rate away from negative words, reflecting more negative self-evaluation. The finding for recall was attenuated when individuals with depression were excluded. Measures of self-evaluation bias were not related to eating disorder severity.

DISCUSSION

Using a neurocognitive approach that includes explicit and implicit indices of bias, results suggest that patients with AN have more negative self-evaluation. Due to the cross-sectional design, additional studies are needed to further evaluate directionality.

PUBLIC SIGNIFICANCE

Negative self-evaluation/low self-esteem is thought to contribute to eating disorder symptoms. Findings of this study using a neurocognitive task to probe self-evaluation suggested that individuals with anorexia nervosa have more negative self-evaluation, reflected by endorsing and remembering more negative (than positive) words compared to healthy controls, and doing so faster. Targeting the construct of negative self-evaluation in treatment of AN may be warranted.

Days between sessions predict attrition in text-based internet intervention of Binge Eating Disorder

BACKGROUND

The number of days between treatment sessions is often overlooked as a predictor of attrition in psychotherapy. In text-based Internet interventions, days between sessions may be a simple yet powerful predictor of attrition.

OBJECTIVE

We hypothesized that a larger number of days between sessions increased the likelihood of attrition among participants with Binge Eating Disorder (BED) in a 12-session Internet-based cognitive behavioral therapy (iCBT) program. Participants could work on the sessions whenever convenient for them and received written support from a psychologist.

MATERIAL AND METHODS

We compared 201 adult participants with mild to moderate BED (85 non-completers and 116 completers) on the number of days between sessions to predict attrition rates.

RESULTS

Mixed model binomial logistic regression showed that non-completers spent significantly more days between sessions across the first four treatment sessions (1-4) when controlling for age, gender, and intake measures of BMI, BED, overall health status (EQ VAS), and depression symptoms (MDI) (OR = 1.042, p < .001). Age (OR = 0.976, p < .001) and EQ VAS (OR = 0.984, p < .001) were also significant. The risk of attrition increased by 4.2 % for each additional day participants spent completing a session.A receiver operating characteristic (ROC) curve analysis showed that classification accuracy increased across sessions from 61.1 % in session 1 and 65.7 % in session 2 to 68.8 % in session 3 and 73.2 % in session 4. The optimal cut-off point in session 4 was 17.5 days, which detected 60.4 % of non-completers (sensitivity) and 78.4 % of completers (specificity).An exploratory repeated measures of ANOVA of days between sessions showed a significant within-subjects effect, where both non-completers and completers spent more days between sessions as they progressed from sessions 1 through 4 (F = 20.54, df = 3, p < .001). There was no interaction effect, suggesting that the increase in slope did not differ between non-completers and completers.

CONCLUSIONS

Participants spending more days between sessions are at increased risk of dropping out of treatment. This may have important implications for identifying measures to reduce attrition, e.g., intensifying interventions through automated reminders or therapist messages. Our findings may have important transdiagnostic implications for text-based Internet interventions. Further studies should investigate the predictive value of days between sessions in other diagnoses.

Severity of Binge Eating Behavior among Overweight College Students in Taiwan and Associated Factors

BACKGROUND

Binge eating (BE) is considered a marker of obesity and overweight and a significant characteristic of feeding and eating disorders. Despite the high prevalence of obesity on college campuses, the issue of BE among college students in Taiwan has received little attention. The aim of this study was to investigate BE behavior among overweight college students in Taiwan and associated factors.

METHODS

This study utilized a cross-sectional survey. A total of 300 overweight college students were recruited through convenience sampling. Data were collected using a self-administered Binge Eating Scale (BES) and a body weight composition monitor (Model No. OMRON, HBF-126) and analyzed using descriptive statistics, correlation analysis, and regression analysis.

RESULTS

The average BES score was 10.67 (SD = 6.66, 0-34). With a BES score of 17 as the cut-off point, 17.3% (n = 52) of the participants were found to have moderate or severe BE behavior. Analysis of the demographic and psychosocial data using Spearman's rho rank correlation coefficient revealed that sex, body mass index (BMI), uncontrolled eating, weight loss diets, academic stress, peer competition, interpersonal distress, and unpleasant or major life events were significantly correlated with BE behavior and its probability (r_s = -0.14-0.15, p < 0.05). Furthermore, logistic regression analysis indicated that the odds ratio of the BES scores of female participants and those who stated to have experienced uncontrolled eating, weight loss diets, peer competition, and interpersonal distress was 1.05-6.04 times those of male participants and those without such experiences (p < 0.05).

CONCLUSION

The study found that nearly one-fifth of participants presented moderate to severe levels of BE behaviors, and these were significantly correlated with sex and external environmental stress. This study suggests early intervention from campus psychological health personnel to provide proper therapy.

Executive Functions of Adults with Binge-Eating Disorder: The Role of Weight Status and Psychopathology

Findings on executive functions (EFs) in binge-eating disorder (BED) are inconsistent and possibly biased by associated comorbidities. This study aimed to identify whether distinct levels of physical and mental comorbidity are related to EFs in BED. General and food-specific EFs in n = 77 adults with BED were compared to population-based norms and associations with weight status, depressive symptoms, and eating disorder psychopathology were analyzed. To detect within-sample patterns of EF performance, k-means clustering was applied. The results indicated that participants' general EFs were within the average range with slight deficits in alertness. While depression and eating disorder psychopathology were unrelated to EFs, weight status was associated with food-specific attentional bias that was significantly higher in obesity class 2 than in overweight/obesity class 1 and obesity class 3. Four meaningful clusters with distinct strengths and impairments in general and food-specific EFs but without differences in clinical variables were identified. Altogether, adults with BED showed few specific deficits compared to normative data. Performance was unrelated to depression and eating disorder psychopathology, while weight status was associated with food-specific EFs only. The results highlight the need for longitudinal studies to evaluate the relevance of EFs in BED development and maintenance in neurologically healthy adults.

Implicit Attitudes Towards Weight, One’s Own Body and its Relation to Food in Women with Overweight and Obesity

Background

Theoretical models emphasize the importance of implicit self-related weight attitudes for the maintenance of body dissatisfaction. Even though body dissatisfaction is increased in obesity, only general implicit weight-related attitudes have been investigated so far. Therefore, the present study assessed self-related and general implicit weight attitudes and their relation to food.

Methods

Women with overweight and obesity (OW; n = 71) and women with normal weight (NW; n = 44) completed three implicit tasks to (1) assess attitudes towards persons with normal weight and overweight in general, (2) attitudes towards one’s own body, and (3) the association between one’s own body and food.

Results

While both groups showed an implicit preference towards persons with normal weight relative to persons with overweight, only women with OW showed a significantly stronger negative implicit attitude towards their own body and a stronger association between food and one’s own body. Additionally, self-related and not general implicit weight attitudes correlated significantly with body dissatisfaction and eating pathology.

Conclusions

The results highlight the importance of self-related implicit attitudes and their relation to body dissatisfaction and eating pathology in women with overweight and obesity. Targeting these self-related implicit weight attitudes might help to improve obesity treatments.

Implicit bias to food and body cues in eating disorders: a systematic review

BACKGROUND

Rigid, restrictive eating patterns, fear of gaining weight, body image concerns, but also binge eating episodes with loss of control leading to overweight, at times followed by compensatory measures to control weight, are typical symptoms in eating disorders (EDs). The regulation of food intake in EDs may underlie explicit processes that require cognitive insight and conscious control or be steered by implicit mechanisms that are mostly automatic, rapid, and associated with affective-rather than cognitive-processing. While introspection is not capable of assessing implicit responses, so-called indirect experimental tasks can assess implicit responses underlying a specific behavior by-passing the participant's consciousness. Here, we aimed to present the current evidence regarding studies on implicit biases to food and body cues in patients with EDs.

METHODS

We performed a systematic review (PRISMA guidelines). We included controlled studies performed in clinical ED cohorts (vs. healthy control subjects or another control condition, e.g., restrictive vs. binge/purge AN) and using at least one indirect assessment method of interest.

RESULTS

Out of 115 screened publications, we identified 29 studies fulfilling the eligibility criteria, and present a synthesis of the essential findings and future directions.

CONCLUSION

In this emerging field of research, the present work provides cornerstones of evidence highlighting aspects of implicit regulation in eating disorders. Applying both direct (e.g., self-reports) and indirect measures for the assessment of both explicit and implicit responses is necessary for a comprehensive investigation of the interplay between these different regulatory mechanisms and eating behavior. Targeted training of implicit reactions is already in use and represents a useful future tool as an add-on to standard psychotherapeutic treatments in the battle against eating disorders.

EVIDENCE LEVEL

1 (systematic review).

A Systematic Review Of Implicit Attitudes And Their Neural Correlates In Eating Behaviour

An increasing number of studies suggests that implicit attitudes toward food and body shape predict eating behaviour and characterize patients with eating disorders (EDs). However, literature has not been previously analysed, thus differences between patients with EDs and healthy controls and the level of automaticity of the processes involved in implicit attitudes are still matters of debate. The present systematic review aimed to synthetize current evidence from papers investigating implicit attitudes towards food and body in healthy and EDs populations. PubMed, EMBASE (Ovid), PsycINFO, Web of Science and Scopus were systematically screened and 183 studies using different indirect paradigms were included in the qualitative analysis. The majority of studies reported negative attitudes towards overweight/obese body images in healthy and EDs samples and weight bias as a diffuse stereotypical evaluation. Implicit food attitudes are consistently reported as valid predictors of eating behaviour. Few studies on the neurobiological correlates showed neurostimulation effects on implicit attitudes, but the automaticity at brain level of implicit evaluations remains an open area of research. In conclusion, implicit attitudes are relevant measures of eating behaviour in healthy and clinical settings, although evidence about their neural correlates is limited.

A bifactor analysis of the Weight Bias Internalization Scale: What are we really measuring?

Internalized weight stigma (IWS) has been linked with disordered eating behavior, both directly, and as a mediator of the relationship between experienced weight stigma and maladaptive coping. However, the construct of IWS is highly correlated with the related constructs of body image and global self-esteem, and the three constructs may better be represented by underlying trait self-judgment. This overlap is not generally accounted for in existing studies. The present study investigated the shared variance between self-esteem, body image, and IWS in an international sample of higher-weight individuals. Bifactor analysis confirmed that the intermediary role of IWS in the relationship between experienced stigma and self-reported eating behavior was largely accounted for by aspects of body image and global self-esteem. Greater conceptual clarity in the study of IWS is needed to understand the mechanisms via which societal weight stigma impacts on individuals' self-directed judgments and downstream health-related behaviors.

Self-image and 12-month outcome in females with eating disorders: extending previous findings

BACKGROUND

The interpersonal Structural Analysis of Social Behavior (SASB) model of self-image has repeatedly proven valuable in relation to eating disorder (ED) symptoms and in predicting ED outcome.

OBJECTIVE

We studied the association between initial self-image according to the SASB and 12-month outcome, in five diagnostic groups of female ED patients. Based on previous findings, we expected autonomy related variables (self-control/autonomy) would strongly predict outcome in anorexia nervosa (AN) groups, whereas variables related to affiliation (self-attack/love) would moderately predict outcome in bulimia nervosa (BN).

METHOD

Participants were adult female patients, of whom 457 had AN restrictive type, 228 AN binge/purge subtype, 861 BN, 505 other specified ED and 170 binge eating disorder. Data came from the Stepwise clinical database in Sweden. Outcomes were presence/absence of ED diagnosis and self-rated ED symptoms, and we controlled for baseline ED pathology, BMI, age and general psychiatric symptoms.

RESULTS

Regression analyses showed that although the pattern differed somewhat between diagnostic groups, high initial self-love and low self-attack/self-blame predicted a more positive 12-month outcome. In some groups (AN/R in particular), these variables remained important even when baseline pathology and age were included in the analyses.

DISCUSSION

Self-image aspects once again display substantial power in predicting outcome in EDs. In AN/R patients, self-love plays an almost as crucial a role as baseline ED pathology in relation to 12-month outcome.

Two sides of weight bias in adolescent binge-eating disorder: Adolescents' perceptions and maternal attitudes

OBJECTIVE

Adolescents with binge-eating disorder (BED) are suffering from weight teasing and, as found in adult BED, are likely to internalize weight bias. Weight teasing by mothers accounts for psychopathology in overweight (OW), but stigmatization sources are largely unknown in BED. This study sought to address weight bias in adolescents with OW and BED by examining adolescents' perceived parental weight teasing and weight bias internalization in relation to their eating disorder psychopathology and maternal stigmatizing attitudes and beliefs.

METHOD

Adolescents with OW and BED (BED; n = 40) were compared to a socio-demographically matched group with OW only and a normal-weight control group (NW; each n = 25). They filled out the Perception of Teasing Scale, with parents as the source of teasing, the Weight Bias Internalization Scale and the Eating Disorder Examination-Questionnaire. Their mothers filled out the Attitudes Toward and Beliefs about Obese Persons Scales.

RESULTS

Significantly higher perceived parental weight teasing and weight bias internalization were found in BED compared to OW and NW. Maternal stigmatizing attitudes and beliefs did not differ significantly between groups and were not correlated with adolescents' perceptions of being stigmatized. Perceived parental weight teasing was associated with adolescents' eating disorder psychopathology, however, this association was fully mediated by weight bias internalization.

DISCUSSION

Results indicate that adolescents with OW and BED perceive weight teasing in families. As we found no significant association between adolescents' perceptions of being stigmatized and maternal stigmatizing attitudes, future research should examine parent-child interaction or implicit measures of stigmatizing attitudes.

Personality Traits and Weight Loss Surgery Outcome

PURPOSE OF THE REVIEW

To update the recent findings on the influence of personality features on postoperative weight loss in patients undergoing bariatric surgery.

RECENT FINDINGS

Several studies investigated the influence of pre-surgical psychological variables on the outcome of bariatric surgery, but the effective role of personality factors (i.e., both normal personality traits and personality disturbances) in shaping bariatric surgery outcome is still unclear. We analyzed nine recent papers that examined the impact of pre-operative personality traits on postoperative weight loss among individuals undergoing surgery for severe obesity. A personality pattern denoting the ability to self-regulate in spite of the urges or demands of the moment emerged as a robust predictor of good outcome across studies, independently from baseline psychiatric comorbidity and personality disorders.

The Effects of Obesity-Related Health Messages on Explicit and Implicit Weight Bias

The pervasiveness of explicit and implicit weight bias (WB) defined as negative stereotypes and prejudice regarding one’s weight has been observed among individuals of all weight categories. As a source of WB, health messages have been discussed due to reinforcing stigmatizing notions. The present study sought to investigate whether health messages (i.e., eat healthy, become physically active) have the potential to increase explicit and implicit WB. Participants (N = 144) from the community were randomized to either an experimental group (EG) or a control group (CG). While the EG was presented with health messages, the CG was presented with neutral information. Before and after manipulation, participants completed measures of explicit and implicit WB. Paired samples t-test revealed no differences in explicit WB after manipulation, however, a small effect decrease of implicit WB in the EG but not in the CG was found. This study provided evidence that health messages might have differential impact to change WB. According to dual-model approaches, explicit and implicit WB tap into two different information processing systems, and thus were differentially affected by health messages. Brief exposure to health messages might have the potential to contribute to health behavior and to mitigate implicit WB.

Weight Stigma Reduction and Genetic Determinism

One major approach to weight stigma reduction consists of decreasing beliefs about the personal controllability of-and responsibility for-obesity by educating about its biogenetic causes. Evidence on the efficacy of this approach is mixed, and it remains unclear whether this would create a deterministic view, potentially leading to detrimental side-effects. Two independent studies from Germany using randomized designs with delayed-intervention control groups served to (1) develop and pilot a brief, interactive stigma reduction intervention to educate N = 128 university students on gene × environment interactions in the etiology of obesity; and to (2) evaluate this intervention in the general population (N = 128) and determine mechanisms of change. The results showed (1) decreased weight stigma and controllability beliefs two weeks post-intervention in a student sample; and (2) decreased internal attributions and increased genetic attributions, knowledge, and deterministic beliefs four weeks post-intervention in a population sample. Lower weight stigma was longitudinally predicted by a decrease in controllability beliefs and an increase in the belief in genetic determinism, especially in women. The results underline the usefulness of a brief, interactive intervention promoting an interactionist view of obesity to reduce weight stigma, at least in the short term, lending support to the mechanisms of change derived from attribution theory. The increase in genetic determinism that occurred despite the intervention's gene × environment focus had no detrimental side-effect on weight stigma, but instead contributed to its reduction. Further research is warranted on the effects of how biogenetic causal information influences weight management behavior of individuals with obesity.

Should the IDEFICS outcomes have been expected?

The Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS) study evaluated with a large sample a comprehensive carefully planned obesity prevention intervention targeting multiple levels of influence that were culturally adapted to the situations in eight European countries. Despite the great effort and attention to detail, the IDEFICS study did not achieve its targeted adiposity or behaviour change objectives. Should we be surprised that the IDEFICS trial did not have its intended effects? We think not, and would have been surprised if it did. Recent research has revealed the lack of consistent meaningful relationships between several apparently obesogenic behaviours and adiposity, weak or no relationships among behavioural change procedures, mediating variables and targeted behaviours and inadequate attention to moderating effects. Future obesity prevention interventions would benefit from a more thorough understanding of the complex relationships that have been hypothesized and the interrelationships with biological factors. While systems modelling has been proposed as providing the solution, important less complex identification of new constructs, new relationships and community interventions are still needed, both to find innovative solutions and to provide input into the systems models. We should question results from cross-sectional studies and be satisfied only with longitudinal or experimental tests of relationships.

Diagnosing binge eating disorder in a primary care setting

Binge eating disorder (BED), now recognized as a distinct eating disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, is the most prevalent eating disorder. Although nearly half of individuals with BED are obese, BED also occurs in nonobese individuals. Despite the relatively high percentage of weight loss treatment-seeking individuals meeting BED criteria, primary care physicians may not be familiar with or have ever diagnosed BED. Many providers may also have difficulty distinguishing BED as a contributory factor in obesity. This review differentiates BED from other causes of obesity by describing how obese individuals with BED differ from obese individuals without BED and from nonobese individuals with BED in areas including psychopathology, behavior, genetics, physiology, quality of life and productivity. The ways in which health-care providers can identify individuals who may have BED are also highlighted so the proper course of treatment is pursued. Overall, obese individuals with BED demonstrate a number of key characteristics that differentiate them from obese individuals without eating disorders, including increased impulsivity in response to food stimuli with loss of control over eating, resulting in the consumption of more calories. They also experience significant guilt and other negative emotions following a meal. In addition, individuals with BED patients have more psychiatric comorbidity, display more psychopathology, exhibit longer binge durations, consume more meals as snacks during the day and have less dietary restraint compared with individuals with BED who are not obese. However, the differences between individuals with BED who are obese versus not obese are not as prominent. Taken together, the evidence appears to support the conclusion that BED is a unique and treatable neurobehavioral disorder associated with distinct behavioral and psychological profiles and distinct medical and functional outcomes, and that it is not merely a subtype of obesity.

Health Consequences of Weight Stigma: Implications for Obesity Prevention and Treatment

Despite decades of research documenting consistent stigma and discrimination against individuals with obesity, weight stigma is rarely considered in obesity prevention and treatment efforts. In recent years, evidence has examined weight stigmatization as a unique contributor to negative health outcomes and behaviors that can promote and exacerbate obesity. This review summarizes findings from published studies within the past 4 years examining the relationship between weight stigma and maladaptive eating behaviors (binge eating and increased food consumption), physical activity, weight status (weight gain and loss and development of obesity), and physiological stress responses. Research evaluating the effects of weight stigma present in obesity-related public health campaigns is also highlighted. Evidence collectively demonstrates negative implications of stigmatization for weight-related health correlates and behaviors and suggests that addressing weight stigma in obesity prevention and treatment is warranted. Key questions for future research to further delineate the health effects of weight stigmatization are summarized.

Stigma and eating and weight disorders

Although research has consistently documented the prevalence and negative health implications of weight stigma, little is known about the stigma associated with eating disorders. Given that weight stigma is a risk factor associated with disordered eating, it is important to address stigma across the spectrum of eating and weight disorders. The aim of this review is to systematically review studies in the past 3 years evaluating stigma in the context of obesity and eating disorders (including binge eating disorder, bulimia nervosa, and anorexia nervosa). Physical and psychological health consequences of stigma for individuals with obesity and eating disorders are discussed. Recent studies on weight stigma substantiate the unique influence of stigma on psychological maladjustment, eating pathology, and physiological stress. Furthermore, research documents negative stereotypes and social rejection of individuals with eating disorder subtypes, while attributions to personal responsibility promote blame and further stigmatization of these individuals. Future research should examine the association of stigma related to eating disorders and physical and emotional health correlates, as well as its role in health-care utilization and treatment outcomes. Additional longitudinal studies assessing how weight stigma influences emotional health and eating disorders can help identify adaptive coping strategies and improve clinical care of individuals with obesity and eating disorders.

Weight stigma "gets under the skin"-evidence for an adapted psychological mediation framework: a systematic review

OBJECTIVE

Research consistently shows a negative view of individuals with obesity in the general public and in various other settings. Stigma and discrimination can be considered chronic stressors, as these factors have a profound impact on the psychological well-being of the affected individuals. This article proposes a framework that entails a mediation of the adverse effects of discrimination and stigmatization on mental well-being through elevated psychological risk factors that are not unique to weight but that could affect overweight and normal-weight individuals alike.

METHODS

A systematic review was conducted to assess the prevalence of psychological risk factors, such as self-esteem and coping, in individuals with obesity.

RESULTS

Forty-six articles were assessed and included for detailed analysis. The number of studies on these topics is limited to certain dimensions of psychological processes. The best evaluated association of obesity and psychosocial aspects is seen for self-esteem. Most studies establish a negative association of weight and self-esteem in children and adults. All studies with mediation analysis find a positive mediation through psychological risk factors on mental health outcomes.

CONCLUSIONS

This review shows that elevated psychological risk factors are existent in individuals with obesity and that they may be a mediator between weight discrimination and pathopsychological outcomes.

Psychosocial, behavioural, pedagogical, and nutritional proposals about how to encourage eating a healthy breakfast

BACKGROUND

Even if more and more evidences have highlighted the importance of breakfast in the growth and development of children, from 10 to 30% of US and European children and adolescents regularly skip breakfast. Thus, there is still a lot to be done before breakfast becomes a daily habit. The aim of this paper is to try and understand how it is possible to overcome the real or imaginary difficulties associated with skipping breakfast by psychosocial, behavioural, pedagogical and nutritional proposals.

DISCUSSION

Schools are the best context where perform healthy interventions because it is here that children learn about the importance of good health at an age when the school still plays a major role in their education. Some school interventions, based on solid theories as the Self Determination Theory and the Behaviour Analysis, have been implemented in the last years to promote health behaviour such as intake of fruit and vegetables and physical activities. Cognitive behaviour therapy is the most closely monitored type of treatment/cure for obesity in randomised controlled trials. Moreover some associations such as the National Association of Food Science Specialists have drawn an own method to encourage food education at school and promote the importance of prevention. These projects could be used as starting point to perform interventions focus on breakfast.

SUMMARY

Increase the consumption of breakfast between children is very important. Efforts should be done to drawn new school projects based on scientific-evidences.