Predictors and moderators of treatment outcome in a randomized clinical trial for binge-eating disorder

Relationship of Genetic Polymorphisms and Microbial Composition with Binge Eating Disorder: A Systematic Review

Humans are the result of an evolutionary process, and because of this, many biological processes are interconnected with each other. The intestine-brain axis consists of an intricately connected neuronal-neuroendocrine circuit that regulates the sensation of hunger and satiety. Genetic variations and the consumption of unnatural diets (ultra-processed foods, high contents of sugars, etc.) can override this circuit and cause addiction to certain foods and/or the inability to feel satiety in certain situations. The patients who come to consultations (mainly psychology or nutrition) in an attempt to resolve this problem sometimes fail, which leads to them looking for new strategies based on biological predisposition. This investigation aims to evaluate the genetic studies regarding the microbiota carried out in the last 12 years in humans to try to determine which genes and microbes that have been recently studied are related to patients diagnosed with binge eating disorder or compulsive eating (presenting obesity or not). The protocol followed the PRISMA statement, and the following databases were searched from 2012 until the present day: PubMed, PsycINFO, SCOPUS, and Web of Science. Twenty-four international articles were analyzed, including cross-sectional or exploratory studies; five of them referred to the microbial composition, and in nineteen, the existence of genetic polymorphisms present in binge eating disorder or in compulsive eating could be observed: DRD2, OPRM1, COMT, MC4R, BNDF, FTO, SLC6A3, GHRL, CARTPT, MCHR2, and LRP11. Even though there is still much to investigate on the subject, it must be highlighted that, in the last 4 years, a two-fold increase has been observed in potential markers and in studies related to the matter, also highlighting the importance of different analyses in relation to psychosocial factors and their interaction with the genetic and microbial factors, for which research on the matter must be continued.

Evaluating dietary restriction as a maintaining factor in binge-eating disorder

OBJECTIVE

Prominent theories of binge-eating (BE) maintenance highlight dietary restriction as a key precipitant of BE episodes. Consequently, treatment approaches for eating disorders (including binge-eating disorder; BED) seek to reduce dietary restriction in order to improve BE symptoms. The present study tested the hypothesis that dietary restriction promotes BE among 112 individuals with BED.

METHODS

Participants completed a 7-day ecological momentary assessment (EMA) protocol before and after completing 17 weeks of either Integrative Cognitive-Affective Therapy or guided self-help cognitive behavioral therapy. Analyses examined whether dietary restriction on 1 day of the baseline EMA protocol predicted risk for BE later that same day, and on the following day. Changes in dietary restriction over the course of treatment were also evaluated as a predictor of change in BE from pre-treatment to post-treatment. Baseline dietary restraint was examined as a moderator of the above associations.

RESULTS

Dietary restriction did not predict BE later the same day, and changes in restriction were not related to changes in BE across treatment, regardless of baseline dietary restraint levels. Restriction on 1 day did predict increased BE risk on the following day for individuals with higher levels of dietary restraint, but not those with lower levels.

DISCUSSION

These findings challenge the assumption that dietary restriction maintains BE among all individuals with BED. Rather, results suggest that dietary restriction may be largely unrelated to BE maintenance in this population, and that reducing dietary restriction generally does not have the intended effect on BE frequency.

Web-based guided self-help cognitive behavioral therapy-enhanced versus treatment as usual for binge-eating disorder: a randomized controlled trial protocol

Binge-eating disorder (BED) is a psychiatric disorder characterized by recurrent episodes of eating a large amount of food in a discrete period of time while experiencing a loss of control. Cognitive behavioral therapy-enhanced (CBT-E) is a recommended treatment for binge-eating disorder and is typically offered through 20 sessions. Although binge-eating disorder is highly responsive to CBT-E, the cost of treating these patients is high. Therefore, it is crucial to evaluate the efficacy of low-intensity and low-cost treatments for binge-eating disorder that can be offered as a first line of treatment and be widely disseminated. The proposed noninferiority randomized controlled trial aims to determine the efficacy of web-based guided self-help CBT-E compared to treatment-as-usual CBT-E. Guided self-help will be based on a self-help program to stop binge eating, will be shorter in duration and lower intensity, and will require fewer therapist hours. Patients with binge-eating disorder (N = 180) will be randomly assigned to receive guided self-help or treatment-as-usual. Assessments will take place at baseline, mid-treatment, at the end of treatment, and at 20- and 40-weeks post-treatment. Treatment efficacy will be measured by examining the reduction in binge-eating days in the previous 28 days between baseline and the end of treatment between groups, with a noninferiority margin (Δ) of 1 binge-eating day. Secondary outcomes will include full remission, body shape dissatisfaction, therapeutic alliance, clinical impairment, health-related quality of life, attrition, and an economic evaluation to assess cost-effectiveness and cost-utility. The moderators examined will be baseline scores, demographic variables, and body mass index. It is expected that guided self-help is noninferior in efficacy compared to treatment-as-usual. The proposed study will be the first to directly compare the efficacy and economically evaluate a low-intensity and low-cost binge-eating disorder treatment compared to treatment-as-usual. If guided self-help is noninferior to treatment-as-usual in efficacy, it can be widely disseminated and used as a first line of treatment for patients with binge-eating disorder. The Dutch trial register number is R21.016. The study has been approved by the Medical Research Ethics Committees United on May 25th, 2021, case number NL76368.100.21.

New understandings meet old treatments: putting a contemporary face on established protocols

In the twenty years since the publication of the most widely used treatment manuals describing evidence-based therapies for eating disorders, there have been some substantial advances in the field. New methods of delivering treatments have been trialled and our perception of mental health has advanced; significant cultural changes have led to shifts in our societal landscape; and new technologies have allowed for more in-depth research to be conducted. As a result, our understanding of eating disorders and their treatment has broadened considerably. However, these new insights have not necessarily been translated into improved clinical practice. This paper highlights the changes we consider to have had the greatest impact on our work as experienced clinical psychologists in the field and suggests a list of new learnings that might be incorporated into clinical practice and research design.

Predictors of neurofeedback treatment outcome in binge-eating disorder: An exploratory study

OBJECTIVE

Knowledge on predictors for treatment response to psychotherapy in binge-eating disorder (BED) is mixed and not yet available for increasingly popular neurofeedback (NF) treatment targeting self-regulation of aberrant brain activity. This study examined eating disorder- and psychopathology-related predictors for NF treatment success in BED.

METHOD

Patients with BED (N = 78) were randomized to 12 sessions of real-time functional near-infrared spectroscopy (rtfNIRS)-NF, targeting individual prefrontal cortex signal up-regulation, electroencephalography (EEG)-NF, targeting down-regulation of fronto-central beta activity, or waitlist (WL). The few studies assessing predictors for clinical outcomes after NF and evidenced predictors for psychotherapy guided the selection of baseline eating disorder-related predictors, including objective binge-eating (OBE) frequency, eating disorder psychopathology (EDP), food cravings, and body mass index (BMI), and general psychopathology-related predictors, including depressive and anxiety symptoms, impulsivity, emotion dysregulation, and self-efficacy. These questionnaire-based or objectively assessed (BMI) predictors were regressed on outcomes OBE frequency and EDP as key features of BED at post-treatment (t1) and 6-month follow-up (t2) in preregistered generalized mixed models (https://osf.io/4aktp).

RESULTS

Higher EDP, food cravings, and BMI predicted worse outcomes across all groups at t1 and t2. General psychopathology-related predictors did not predict outcomes at t1 and t2. Explorative analyses indicated that lower OBE frequency and higher self-efficacy predicted lower OBE frequency, and lower EDP predicted lower EDP after the waiting period in WL.

DISCUSSION

Consistent with findings for psychotherapy, higher eating disorder-related predictors were associated with higher EDP and OBE frequency. The specificity of psychopathological predictors for NF treatment success warrants further examination.

PUBLIC SIGNIFICANCE

This exploratory study firstly assessed eating disorder- and psychopathology-related predictors for neurofeedback treatment outcome in binge-eating disorder and overweight. Findings showed an association between higher eating disorder symptoms and worse neurofeedback outcomes, indicating special needs to be considered in neurofeedback treatment for patients with a higher binge-eating disorder symptom burden. In general, outcomes and assignment to neurofeedback treatment may be improved upon consideration of baseline psychological variables.

Causal discovery analysis: A promising tool in advancing precision medicine for eating disorders

OBJECTIVE

Precision medicine (i.e., individually tailored treatments) represents an optimal goal for treating complex psychiatric disorders, including eating disorders. Within the eating disorders field, most treatment development efforts have been limited in their ability to identify individual-level models of eating disorder psychopathology and to develop and apply an individually tailored treatment for a given individual's personalized model of psychopathology. In addition, research is still needed to identify causal relationships within a given individual's model of eating disorder psychopathology. Addressing this limitation of the current state of precision medicine-related research in the field will allow us to progress toward advancing research and practice for eating disorders treatment.

METHOD

We present a novel set of analytic tools, causal discovery analysis (CDA) methods, which can facilitate increasingly fine-grained, person-specific models of causal relations among cognitive, behavioral, and affective symptoms.

RESULTS

CDA can advance the identification of an individual's causal model that maintains that individuals' eating disorder psychopathology.

DISCUSSION

In the current article, we (1) introduce CDA methods as a set of promising analytic tools for developing precision medicine methods for eating disorders including the potential strengths and weaknesses of CDA, (2) provide recommendations for future studies utilizing this approach, and (3) outline the potential clinical implications of using CDA to generate personalized models of eating disorder psychopathology.

PUBLIC SIGNIFICANCE STATEMENT

CDA provides a novel statistical approach for identifying causal relationships among variables of interest for a given individual. Person-specific causal models may offer a promising approach to individualized treatment planning and inform future personalized treatment development efforts for eating disorders.

Psychotherapies for eating disorders: findings from a rapid review

BACKGROUND

Psychotherapy is considered central to the effective treatment of eating disorders-focusing on behavioural, psychological, and social factors that contribute to the illness. Research indicates psychotherapeutic interventions out-perform placebo, waitlist, and/or other treatments; but, outcomes vary with room for major improvement. Thus, this review aims to (1) establish and consolidate knowledge on efficacious eating disorder psychotherapies; (2) highlight select emerging psychotherapeutic interventions; and (3) identify knowledge gaps to better inform future treatment research and development.

METHODS

The current review forms part of a series of Rapid Reviews published in a special issue in the Journal of Eating Disorders to inform the development of the Australian-government-funded National Eating Disorder Research and Translation Strategy 2021-2031. Three databases were searched for studies published between 2009 and 2023, published in English, and comprising high-level evidence studies (meta-analyses, systematic reviews, moderately sized randomised controlled studies, moderately sized controlled-cohort studies, and population studies). Data pertaining to psychotherapies for eating disorders were synthesised and outlined in the current paper.

RESULTS

281 studies met inclusion criteria. Behavioural therapies were most commonly studied, with cognitive-behavioural and family-based therapies being the most researched; and thus, having the largest evidence-base for treating anorexia nervosa, bulimia nervosa, and binge eating disorder. Other therapies, such as interpersonal and dialectical behaviour therapies also demonstrated positive treatment outcomes. Emerging evidence supports specific use of Acceptance and Commitment; Integrative Cognitive Affective; Exposure; Mindfulness; and Emotionally-Focused therapies; however further research is needed to determine their efficacy. Similarly, growing support for self-help, group, and computer/internet-based therapeutic modalities was noted. Psychotherapies for avoidant/restrictive food intake disorder; other, and unspecified feeding and eating disorders were lacking evidence.

CONCLUSIONS

Currently, clinical practice is largely supported by research indicating that behavioural and cognitive-behavioural psychotherapies are most effective for the treatment of eating disorders. However, the efficacy of psychotherapeutic interventions varies across studies, highlighting the need for investment and expansion of research into enhanced variants and novel psychotherapies to improve illness outcomes. There is also a pressing need for investigation into the whole range of eating disorder presentations and populations, to determine the most effective interventions.

Elevated reward, emotion, and memory region response to thin models predicts eating disorder symptom persistence: A prospective functional magnetic resonance imaging study

Because few studies have identified biological factors that predict the persistence of eating pathology, we tested the hypotheses that elevated responsivity of brain regions implicated in reward valuation to thin models and high-calorie binge foods would predict the persistence of eating pathology. We analyzed data from 146 women (Mage = 21.87 ± 3.81) with threshold or subthreshold anorexia nervosa, bulimia nervosa, binge eating disorder, or purging disorder who completed functional magnetic resonance imaging scans assessing neural response to thin models and binge foods at baseline, were randomized to two eating disorder treatments or a waitlist control condition and completed diagnostic interviews that assessed change in symptoms over 2.5-month follow-up. Elevated activation in regions associated with memory (parahippocampal gyrus r = .38; hippocampus r = .25) and with reward valuation and emotional salience (amygdala r = .35) in response to thin versus average-weight models predicted future persistence of an eating disorder symptom composite (all analyses controlled for treatment condition). Neural response to high-calorie binge foods did not predict the persistence of eating disorder symptoms. There was no evidence that either treatment moderated the relation of baseline neural responsivity to thin models to future persistence of eating disorder symptoms, though power for these post hoc analyses was limited. Results suggest that overvaluation of the thin ideal increases the risk for the persistence of eating disorder symptoms but provided no support for the hypothesis that overvaluation of high-calorie foods would predict symptom persistence. Results imply that treatments should seek to reduce the overvaluation of the thin ideal. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Loneliness in Breast Cancer Patients with Early Life Adversity: An Investigation of the Effects of Childhood Trauma and Self-Regulation

Childhood trauma may be prevalent in the general population, and the psychosocial treatment of patients with cancer may require consideration of the effects of such early adversity on the healing and recovery process. In this study, we investigated the long-term effects of childhood trauma in 133 women diagnosed with breast cancer (mean age 51, SD = 9) who had experienced physical, sexual, or emotional abuse or neglect. We examined their experience of loneliness and its associations with the severity of childhood trauma, ambivalence about emotional expression, and changes in self-concept during the cancer experience. In total, 29% reported experiencing physical or sexual abuse, and 86% reported neglect or emotional abuse. In addition, 35% of the sample reported loneliness of moderately high severity. Loneliness was directly influenced by the severity of childhood trauma and was directly and indirectly influenced by discrepancies in self-concept and emotional ambivalence. In conclusion, we found that childhood trauma was common in breast cancer patients, with 42% of female patients reporting childhood trauma, and that these early experiences continued to exert negative effects on social connection during the illness trajectory. Assessment of childhood adversity may be recommended as part of routine oncology care, and trauma-informed treatment approaches may improve the healing process in patients with breast cancer and a history of childhood maltreatment.

Change in impulsivity is prospectively associated with treatment outcomes for binge-eating disorder

BACKGROUND

Impulsivity may be a process underlying binge-eating disorder (BED) psychopathology and its treatment. This study examined change in impulsivity during cognitive-behavioral therapy (CBT) and/or pharmacological treatment for BED and associations with treatment outcomes.

METHODS

In total, 108 patients with BED (NFEMALE = 84) in a randomized placebo-controlled clinical trial evaluating the efficacy of CBT and/or fluoxetine were assessed before treatment, monthly throughout treatment, at post-treatment (16 weeks), and at 12-month follow-up after completing treatment. Patients completed established measures of impulsivity, eating-disorder psychopathology, and depression, and were measured for height and weight [to calculate body mass index (BMI)] during repeated assessments by trained/monitored doctoral research-clinicians. Mixed-effects models using all available data examined changes in impulsivity and the association of rapid and overall changes in impulsivity on treatment outcomes. Exploratory analyses examined whether baseline impulsivity predicted/moderated outcomes.

RESULTS

Impulsivity declined significantly throughout treatment and follow-up across treatment groups. Rapid change in impulsivity and overall change in impulsivity during treatment were significantly associated with reductions in eating-disorder psychopathology, depression scores, and BMI during treatment and at post-treatment. Overall change in impulsivity during treatment was associated with subsequent reductions in depression scores at 12-month follow-up. Baseline impulsivity did not moderate/predict eating-disorder outcomes or BMI but did predict change in depression scores.

CONCLUSIONS

Rapid and overall reductions in impulsivity during treatment were associated with improvements in specific eating-disorder psychopathology and associated general outcomes. These effects were found for both CBT and pharmacological treatment for BED. Change in impulsivity may be an important process prospectively related to treatment outcome.

Machine learning v. traditional regression models predicting treatment outcomes for binge-eating disorder from a randomized controlled trial

BACKGROUND

While effective treatments exist for binge-eating disorder (BED), prediction of treatment outcomes has proven difficult, and few reliable predictors have been identified. Machine learning is a promising method for improving the accuracy of difficult-to-predict outcomes. We compared the accuracy of traditional and machine-learning approaches for predicting BED treatment outcomes.

METHODS

Participants were 191 adults with BED in a randomized controlled trial testing 6-month behavioral and stepped-care treatments. Outcomes, determined by independent assessors, were binge-eating (% reduction, abstinence), eating-disorder psychopathology, and weight loss (% loss, ⩾5% loss). Predictors included treatment condition, demographic information, and baseline clinical characteristics. Traditional models were logistic/linear regressions. Machine-learning models were elastic net regressions and random forests. Predictive accuracy was indicated by the area under receiver operator characteristic curve (AUC), root mean square error (RMSE), and R2. Confidence intervals were used to compare accuracy across models.

RESULTS

Across outcomes, AUC ranged from very poor to fair (0.49-0.73) for logistic regressions, elastic nets, and random forests, with few significant differences across model types. RMSE was significantly lower for elastic nets and random forests v. linear regressions but R2 values were low (0.01-0.23).

CONCLUSIONS

Different analytic approaches revealed some predictors of key treatment outcomes, but accuracy was limited. Machine-learning models with unbiased resampling methods provided a minimal advantage over traditional models in predictive accuracy for treatment outcomes.

Examining changes in binge-eating disorder network centrality and structure in patients treated with cognitive-behavioral therapy versus interpersonal psychotherapy

OBJECTIVE

A sizeable minority of patients with binge-eating disorder (BED) do not fully respond to evidence-based treatments. Evidence to guide refinements of treatments is needed. Conceptualizing BED as arising from a network of symptom-to-symptom interactions allows for identification of the most strongly connected symptoms, which could inform intervention targets. This study estimated networks of BED features at pretreatment and posttreatment to assess whether cognitive behavioral therapy (CBT) and interpersonal psychotherapy (IPT) differentially impacted the interrelationships of BED symptoms/features.

METHODS

Participants were 392 adults (83% women, 88% white) with BED who received CBT (n = 236) or IPT (n = 156) and assessed at pretreatment and posttreatment. Networks were estimated across timepoints and treatments. Expected influence (EI) was calculated; symptoms with the highest EI have the most strong and frequent associations with other symptoms. We also assessed whether the symptoms with the highest and lowest EI predicted posttreatment remission indicators.

RESULTS

In the CBT and IPT networks, shape concern, weight concern, and eating concern had the highest EI at pretreatment and posttreatment. EI significantly increased from pretreatment to posttreatment for some symptoms in CBT but did not change for any symptoms in IPT. Shape concern significantly and positively predicted BED remission indicators in CBT and IPT.

CONCLUSIONS

CBT and IPT similarly impacted interrelations among BED features. Pretreatment EI predicted posttreatment remission indicators, indicating that pretreatment centrality could signal meaningful intervention targets. Clinical implications and avenues for future research are discussed including how personalized network analysis may advance the understanding of the clinical utility of centrality.

PUBLIC SIGNIFICANCE

Cognitive behavioral therapy and interpersonal therapy for binge-eating disorder, which are two leading evidence-based treatments for binge-eating disorder that are quite different in their models and approaches, similarly impacted interrelations among binge-eating disorder symptoms. In addition, the most strongly interconnected symptom predicted indicators of remission. Studying the interrelations among symptoms may provide new insight on how treatments impact symptom relationships and inform intervention targets.

Emotion dysregulation and eating disorder outcome: Prediction, change and contribution of self-image

OBJECTIVES

Eating disorders (EDs) are severe disorders with unsatisfactory outcome. Emotion dysregulation and self-image are suggested maintenance factors; this study examined emotion dysregulation as potential predictor and/or mechanism of change in relation to ED outcome, and associations between change in emotion dysregulation and self-image in relation to outcome.

DESIGN

Registry data from initial and 1-year follow-up assessments for 307 patients with a wide range of EDs in specialized ED treatment were used.

METHODS

Initial and change (∆) in emotion dysregulation were examined as predictors of 1-year outcome. Direct and indirect associations between ∆emotion dysregulation and ∆self-image as either independent variable or mediator in relation to ∆ED psychopathology as dependent were also examined.

RESULTS

Higher initial emotion dysregulation was weakly associated with higher follow-up ED psychopathology, but not remission, while relative increase in emotion dysregulation was associated with both higher follow-up psychopathology and increased risk of still having a diagnosis. Change in emotion dysregulation primarily had an indirect effect (through change in self-image), while change in self-image had a direct effect, on change in ED psychopathology improvement (such that improvement in one was associated with improvement in the other).

CONCLUSIONS

Results identify emotion dysregulation as a potential mechanism of change in relation to ED outcome. However, this association was mainly mediated by change in self-image. Results indicate that, in order to improve emotion regulation as a means to reduce ED psychopathology, improving self-image is essential.

Body image as a multidimensional concept: A systematic review of body image facets in eating disorders and muscle dysmorphia

Body image disturbance is core to the psychopathology of eating disorders (EDs), and related disorders such as muscle dysmorphia (MD). Global measures of body image fail to quantify specific aspects of body image disturbance that characterizes EDs, and may be differentially associated to outcomes. The aim of this systematic review was to provide an overview of specific body image facets and synthesize findings from controlled studies that compared clinical ED/MD and control-comparison groups in body image disturbance. One-hundred sixty-seven studies met inclusion criteria, and reported on comparisons among 30,584 individuals in 28 body image facets, which were more broadly grouped into evaluative, perceptual, cognitive-affective and motivational categories for the purpose of the present review. Effect sizes were calculated as Cohen's d for every comparison between ED and control groups. Body dissatisfaction (evaluative category) was the most prevalent facet assessed across studies (62 %), and differences between clinical and control groups were the largest in this category, especially for bulimia nervosa (d = 1.37). Scarcity of studies with male and MD clinical samples, and use of single-item and non-validated measures, should encourage development of instruments for body image facets pertinent to EDs and MD that can be validly applied across gender.

Which dimensions of emotion dysregulation predict the onset and persistence of eating disorder behaviours? A prospective study

BACKGROUND

Theoretical models highlight the importance of emotion dysregulation as a key risk and maintaining factor for eating disorders. However, most studies testing these theories are cross-sectional. It remains unclear which dimensions of emotion dysregulation account for the onset and persistence of eating disorder behaviours over time.

METHODS

To address these gaps, data were analyzed from 1321 adult women who completed study measures at baseline and eight-month follow-up. The dimensions of emotion dysregulation assessed were five subscales from the abbreviated 16-item Difficulties in Emotion Regulation Scale. Outcomes included the onset (versus asymptomatic) and persistence (versus remission) of binge eating and compensatory behaviours.

RESULTS

Univariate logistic regressions showed that, among initially asymptomatic women, higher baseline levels of each emotion dysregulation dimension (except the "goals" subscale) predicted the onset of binge eating and compensatory behaviours at follow-up. Each dimension also predicted the persistence of compensatory behaviours at follow-up among women endorsing these behaviours at baseline, while the "impulse", "strategies", and "non-acceptance" dimensions predicted the persistence of binge eating. In multivariate analyses, only the "strategies" dimension predicted the onset and persistence of binge eating, while the "non-acceptance" dimension predicted the onset and persistence of compensatory behaviours.

LIMITATIONS

Only a limited number of emotion dysregulation dimensions were tested.

CONCLUSION

Findings demonstrate the importance of emotion dysregulation dimensions in accounting for the onset and maintenance of eating disorder behaviours. The delivery of specific intervention strategies designed to address emotion dysregulation may depend on the risk and symptom profile of an individual.

Change in eating-disorder psychopathology network structure in patients with binge-eating disorder: Findings from treatment trial with 12-month follow-up

OBJECTIVE

Effective treatments exist for binge-eating disorder (BED), although roughly 50% of patients fail to attain binge-eating abstinence. Evidence on how to refine treatments is lacking. Conceptualizing BED as arising from a network of symptom-to-symptom interactions allows for the identification of the most strongly connected symptoms, which could inform intervention targets. This study assessed how BED symptom centrality changed with behaviorally based weight-loss treatments (BBWLTs).

METHODS

Participants were 191 adult patients (71% female, 79% White) with BED with comorbid obesity participating in a randomized controlled trial testing 6-month BBWLTs for BED. Independent assessments of BED symptoms were performed at pretreatment, posttreatment, and 12 months after treatment. Strength centrality indicated how strongly and frequently symptoms were associated with each other in the network. Significant changes in centrality between timepoints were determined using permutation tests.

RESULTS

At pretreatment, overvaluation of shape/weight and preoccupation with shape/weight and food/eating had the highest strength centrality. At posttreatment and 12-month follow-up, dissatisfaction with shape/weight had the highest centrality, which significantly increased from pretreatment.

CONCLUSIONS

The relations among symptoms of BED are not static and change over time with treatment. BBWLTs do not appear to reduce connectivity of overvaluation of shape/weight (the most central BED symptom prior to treatment), but instead increase connectivity of dissatisfaction with shape/weight with other symptoms following treatment. The observed network structure of symptoms following BBWLTs resembles network analyses of people without eating disorders. Findings highlight the importance of understanding how treatments impact symptom relationships, not just symptom intensities. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Comparing the effectiveness and predictors of cognitive behavioural therapy-enhanced between patients with various eating disorder diagnoses: a naturalistic study

Cognitive behaviour therapy-enhanced (CBT-E) is an effective treatment for non-underweight patients with eating disorders. Its efficacy and effectiveness is investigated mostly among transdiagnostic samples and remains unknown for binge eating disorder. The aim of the present study was to assess several treatment outcome predictors and to compare effectiveness of CBT-E among adult out-patients with bulimia nervosa (n=370), binge eating disorder (n=113), and those with a restrictive food pattern diagnosed with other specified feeding and eating disorders (n=139). Effectiveness of CBT-E was assessed in routine clinical practice in a specialised eating disorders centre. Eating disorder pathology was measured with the EDEQ pre- and post-treatment, and at 20 weeks follow-up. Linear mixed model analyses with fixed effect were performed to compare treatment outcome among the eating disorder groups. Several predictors of treatment completion and outcome were examined with a regression analysis. No predictors for drop-out were found, except the diagnosis of bulimia nervosa. Eating disorder pathology decreased among all groups with effect sizes between 1.43 and 1.70 on the EDE-Q total score. There were no differences in remission rates between the three groups at end of treatment or at follow-up. Eating disorder severity at baseline affected treatment response. The results can be generalised to other specialised treatment centres. No subgroup of patients differentially benefited from CBT-E supporting the transdiagnostic perspective for the treatment of eating disorders. Longer-term follow-up data are necessary to measure persistence of treatment benefits.

Key learning aims

(1)

Predictors of Symptom Trajectories After Cognitive-Behavioral Therapy in Adolescents With an Age-Adapted Diagnosis of Binge-Eating Disorder

Although evidence demonstrated efficacy of cognitive-behavioral therapy (CBT) in adolescents with binge-eating disorder (BED), treatment response is heterogeneous. This study uniquely examined baseline predictors of symptom trajectories in N = 73 adolescents (12-20 years) with an age-adapted diagnosis of BED (i.e., based on objective and subjective binge-eating episodes). Based on evidence from adult BED, dietary restraint, overvaluation of weight/shape, and depressive symptoms were used to predict changes in abstinence from binge eating and eating disorder psychopathology after 4 months of individual, face-to-face CBT using growth models. Longitudinal trajectories of abstinence from objective and subjective binge eating and global eating disorder psychopathology assessed via the Eating Disorder Examination were modeled for five time points (pre- and posttreatment, 6-, 12-, and 24-month follow-up). Beyond significant, positive effects for time, no significant predictors for abstinence from binge eating emerged. In addition to significant decreases in eating disorder psychopathology over time, higher pretreatment dietary restraint and overvaluation of weight/shape significantly predicted greater decreases in eating disorder psychopathology over time. Consistent with research in adult BED, adolescents with higher than lower eating disorder-specific psychopathology especially benefit from CBT indicating that restrained eating and overvaluation of weight/shape may be BED-specific prognostic characteristic across developmental stages. Future predictor studies with an additional focus on potential age-specific predictors, such as family factors, and within-treatment processes may be critical in further evaluating treatment-related symptom trajectories in adolescent BED.

Clinical moderators and predictors of cognitive-behavioral therapy by guided-self-help versus therapist-led for binge-eating disorder: Analysis of aggregated clinical trials

OBJECTIVE

Cognitive-behavioral therapy (CBT)-therapist-led (CBTth) and guided-self-help (CBTgsh)-has efficacy for binge-eating disorder (BED) but many patients do not benefit sufficiently. We examined predictors and moderators for these two CBT methods.

METHOD

Data were aggregated from randomized controlled trials (RCTs) testing psychosocial treatments for BED in the U.S. Predictors and moderators of outcomes (treatment completion and binge-eating remission) were examined in N = 457 participants who received either CBTgsh (N = 164) or CBTth (N = 293).

RESULTS

Analyses, adjusting for demographic/clinical variables, indicated CBTth was significantly superior to CBTgsh for treatment completion (odds ratio [OR] = 20.0) and remission (OR = 14.6). For remission, analyses revealed significant predictors (age, treatment length, Weight Concern), a moderator (weight concern [OR = 5.13]), and a significant interaction between CBT-type and treatment length (OR = 2.66). For CBTgsh, longer treatment was associated with less remission, whereas for CBTth, longer treatment was associated with greater remission. For CBTgsh, 44.1% with low weight concern versus 56.3% with high weight concern achieved remission whereas for CBTth, 43.5% with high weight concern and 61.0% with low weight concern achieved remission.

DISCUSSION

Analyses of aggregated RCT BED data, adjusting for demographic/clinical characteristics, indicated superiority (large effect-sizes) in treatment outcomes of CBTth over CBTgsh and that Weight Concern moderated outcomes.

Predictors of treatment response durability in psychotherapy for binge-eating disorder: Examining the roles of self-discrepancy, self-directed style, and emotion dysregulation

OBJECTIVE

To examine changes in hypothesized maintenance mechanisms during treatment as predictors of treatment response durability in binge-eating disorder (BED) treatment, using data from a randomized clinical trial comparing the efficacy of Integrative Cognitive-Affective Therapy for BED with cognitive-behavioral therapy delivered using guided self-help.

METHOD

Adults with BED (N = 112) received 17 weeks of treatment. Regression models were conducted to examine the extent to which changes in hypothesized maintenance mechanisms from baseline to end of treatment predicted treatment outcomes at 6-month follow-up, adjusting for demographics, study site, and baseline level of treatment outcome.

RESULTS

During-treatment reductions in negative self-directed style and emotion dysregulation predicted reductions in the primary treatment outcome (i.e., binge-eating episode frequency) at follow-up. During-treatment reductions in emotion dysregulation also predicted improvements at follow-up across all three secondary treatment outcomes examined (i.e., global eating disorder [ED] psychopathology, depressive symptoms, and anxiety symptoms), as did during-treatment reductions in actual-ideal self-discrepancy and actual-ought self-discrepancy. Increases in positive self-directed style (e.g., self-affirmation) and reductions in negative self-directed style (e.g., self-blame) during treatment each predicted improvements in anxiety symptoms at follow-up. When predictors were examined simultaneously, the most salient predictors of treatment response durability identified were negative self-directed style for binge-eating episode frequency, actual-ought self-discrepancy and emotion dysregulation for depressive symptoms, and emotion dysregulation for anxiety symptoms. No predictors emerged as most salient for global ED psychopathology.

DISCUSSION

Results indicate that negative self-directed style and emotion dysregulation are particularly important treatment targets in relation to behavioral treatment outcomes in BED.

Negative Affectivity and Emotion Dysregulation as Mediators between ADHD and Disordered Eating: A Systematic Review

Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with disordered eating, especially addictive-like eating behavior (i.e., binge eating, food addiction, loss of control overeating). The exact mechanisms underlying this association are unclear. ADHD and addictive-like eating behavior are both associated with negative affectivity and emotion dysregulation, which we hypothesized are mediators of this relationship. The purpose of this systematic review was to review the evidence related to this hypothesis from studies assessing the relationship between childhood or adulthood ADHD symptomatology, negative affectivity, emotion dysregulation and addictive-like eating behavior. The systematic review followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) recommendations. The literature search was conducted in PubMed and PsycINFO (publication date: January 2015 to August 2020; date of search: 2 September 2020). Out of 403 potentially relevant articles, 41 were retained; 38 publications reported that ADHD and disordered eating or addictive-like eating behavior were significantly associated, including 8 articles that suggested a mediator role of negative affectivity or emotion dysregulation. Sixteen publications reported that the association between ADHD symptomatology and disordered eating or addictive-like eating behavior differed according to gender, eating behavior and ADHD symptoms (hyperactivity, impulsivity and inattention). We discuss the practical implications of these findings and directions future research.