Investigating change in network structure of eating disorder symptoms after delivery of a smartphone app-based intervention.

BACKGROUND: Eating disorder (ED) research has embraced a network perspective of psychopathology, which proposes that psychiatric disorders can be conceptualized as a complex system of interacting symptoms. However, existing intervention studies using the network perspective have failed to find that symptom reductions coincide with reductions in strength of associations among these symptoms. We propose that this may reflect failure of alignment between network theory and study design and analysis. We offer hypotheses for specific symptom associations expected to be disrupted by an app-based intervention, and test sensitivity of a range of statistical metrics for identifying this intervention-induced disruption. METHODS: Data were analyzed from individuals with recurrent binge eating who participated in a randomized controlled trial of a cognitive-behavioral smartphone application. Participants were categorized into one of three groups: waitlist (n = 155), intervention responder (n = 49), and intervention non-responder (n = 77). Several statistical tests (bivariate associations, network-derived strength statistics, network invariance tests) were compared in ability to identify change in network structure. RESULTS: Hypothesized disruption to specific symptom associations was observed through change in bivariate correlations from baseline to post-intervention among the responder group but were not evident from symptom and whole-of-network based network analysis statistics. Effects were masked when the intervention group was assessed together, ignoring heterogeneity in treatment responsiveness. CONCLUSION: Findings are consistent with our contention that study design and analytic approach influence the ability to test network theory predictions with fidelity. We conclude by offering key recommendations for future network theory-driven interventional studies.

A call to action for more rigorous research on compassion-focused interventions for eating disorders: Commentary on Paranjothy and Wade (2024).

Paranjothy and Wade's (2024) meta-analysis identifying relations between self-criticism, self-compassion, and disordered eating prompted recommendations for augmenting existing front-line interventions with compassion-focused therapy (CFT) principles among self-critical individuals. While in theory this sounds promising, the reality is that the evidence supporting the use of CFT for eating disorders (EDs) is limited. I argue that before any clinical recommendations can made, more research is needed to better understand the utility of CFT, as well as what precise role self-criticism and self-compassion play in the context of intervention. In this commentary, I present three critical avenues for future research necessary to achieve this level of understanding. These include: (1) identifying moderators of response in clinical trials so that CFT can be safely delivered to those likely to benefit from this approach and avoided for those likely to experience harm; (2) establishing mediators of change so that we can understand whether CFT works through theory-specific or common mechanisms; and (3) testing the causal impact of intervention components so that knowledge on how to most effectively trigger the probable mediators of change can be gathered. This commentary will ideally spark further discussion, collaboration, and rigorous research dedicated to improving ED outcomes. PUBLIC SIGNIFICANCE: This commentary discusses the importance of further research dedicated towards enhancing understanding of the utility of compassion-focused interventions for eating disorders. It calls for more research on (1) testing moderators of response, (2) identifying mechanisms of change, and (3) establishing the most effective intervention components.

Exploration of the individual and combined effects of predictors of engagement, dropout, and change from digital interventions for recurrent binge eating.

OBJECTIVE: Our ability to predict responsiveness to digital interventions for eating disorders has thus far been poor, potentially for three reasons: (1) there has been a narrow set of predictors explored; (2) prediction has mostly focused on symptom change, ignoring other aspects of the user journey (uptake, early engagement); and (3) there is an excessive focus on the unique effects of predictors rather than the combined contributions of a predictor set. We evaluated the univariate and multivariate effects of outcome predictors in the context of a randomized trial (n = 398) of digitally delivered interventions for recurrent binge eating. METHOD: Thirty baseline variables were selected as predictors, ranging from specific symptoms, to key protective factors, to technological acceptance, and to online treatment attitudes. Outcomes included uptake, early engagement, and remission. Univariate (d) and multivariate (D) standardized mean differences were calculated to estimate the individual and combined effects of predictors, respectively. RESULTS: At the univariate level, few predictors produced an effect size larger than what is considered small (d > .20) across outcomes. However, our multivariate approach enhanced prediction (Ds = .65 to 1.12), producing accuracy rates greater than chance (63%-71% accuracy). Less than half of the chosen variables proved to be useful in contributing to predictions in multivariate models. CONCLUSION: Findings suggest that accuracy in outcome prediction from digitally delivered interventions may be better driven by the aggregation of many small effects rather than one or several largely influential predictors. Replication with different data streams (sensor, neuroimaging) would be useful. PUBLIC SIGNIFICANCE: Our ability to predict who will and will not benefit from digital interventions for eating disorders has been poor. We highlight the viability of a multivariate approach to outcome prediction, whereby prediction may be better driven by the aggregation of many small effects rather than one or a few influential predictors.

Trajectories of therapeutic skills use and their dynamic relations to symptom change during cognitive-behavioral therapy for bulimia nervosa.

OBJECTIVE: To examine trajectories of therapeutic skills use and weekly relations between skills use and symptom change during the enhanced version of cognitive-behavioral therapy (CBT-E) for bulimia nervosa (BN). METHOD: Fifty-five adults (M age: 39.0 ± 14.1; 83.9% female; 64.3% White, 93.6% non-Hispanic/Latino) receiving CBT-E for BN-spectrum eating disorders (EDs) self-monitored their use of five therapeutic skills (i.e., regular eating, eating enough to prevent excessive hunger and eating a range of macronutrients, breaking dietary rules, urge management strategies, and mood management strategies) several times per day during treatment. Patients also self-reported their ED symptoms (i.e., frequency of binge eating, compensatory behaviors, and dietary restraint) weekly. We examined trajectories of use of each CBT-E skill and temporal relations between skills use and ED symptoms from week-to-week during treatment. RESULTS: Participants showed significant increases in eating enough to prevent excessive hunger and eating a range of macronutrients from week-to-week (p < .05). Regular eating, eating enough to prevent excessive hunger, and eating a range of macronutrients 1 week predicted lower binge eating and compensatory behaviors the same week and the following week, and urge management strategy use predicted greater binge eating the same week and the following week (p < .05). CONCLUSIONS: Results showed temporal relationships between therapeutic skills use and symptom change on a weekly level, with evidence that using skills targeting dietary restraint was associated with lower BN symptoms. Findings highlight the promise of future work to elucidate the most potent CBT-E skills for symptom improvement and inform more targeted interventions. PUBLIC SIGNIFICANCE: Findings showed weekly relationships between therapeutic skills use and symptom change during treatment, with evidence that using CBT-E skills aimed to reduce dietary restraint (i.e., regular eating, eating enough to prevent excessive hunger, and eating a range of macronutrients) was associated with lower BN symptoms. Future work has the potential to identify the most potent CBT-E skills for symptom improvement and inform more targeted interventions.

A randomized controlled trial of an online single session intervention for body image in individuals with recurrent binge eating.

OBJECTIVE: Theoretical models highlight body image disturbances as central to the maintenance of eating disorders, with empirical evidence finding negative body image to be a robust predictor of treatment nonresponse, relapse and symptom persistence. Accessible, scalable, and inexpensive interventions that can effectively target negative body image across the eating disorders are needed. We developed an online single session intervention (SSI) for negative body image and evaluated its acceptability and efficacy in a randomized controlled trial in individuals with recurrent binge eating. METHOD: Participants with recurrent binge eating were randomly assigned to the SSI (n = 99) or a waitlist (n = 101). Assessments were conducted at baseline, 4 week follow-up, and 8 week follow-up. RESULTS: 81% of participants accessed the SSI, demonstrating reasonable uptake. However, issues with attrition were apparent; a 32% study dropout rate was observed at posttest, while a 58% dropout rate was observed at follow-up. 87% of participants who completed satisfaction measures would recommend the SSI. SSI participants experienced greater improvements in negative body image at both 4 (d = -0.65) and 8 week (d = -0.74) follow-up. Significant between-group effects were also observed on most other secondary symptom measures, though no differences were found for motivations and help-seeking beliefs and intentions. CONCLUSION: Body image-focused self-guided SSIs for recurrent binge are largely accepted by those who are retained in the trial, but are associated with significant attrition. Although SSIs are not intended to replace standard treatment, they may help with short-term symptom management and could play an important role in eating disorder care. PUBLIC SIGNIFICANCE: Single session interventions (SSI) are a potentially accessible, scalable, and cost-effective way to deliver evidence-based treatment content to people with eating disorders. This study shows that an online (SSI) designed to target body image among people with recurrent binge eating is accepted and produced short-term symptom relief.

The Intuitive Eating Scale-3: Development and psychometric evaluation.

Intuitive eating has been found to protect against disordered eating and preserve well-being. Yet, there are methodological (length), conceptual (inconsideration of medical, value-based, and access-related reasons for food consumption), and psychometric (item wording) concerns with its most common measure, the Intuitive Eating Scale-2 (IES-2). To address these concerns, we developed the IES-3 and investigated its psychometric properties with U.S. community adults. Across three online studies, we evaluated the IES-3's factorial validity using exploratory factor analysis (EFA; Study 1; N = 957; Mage = 36.30), as well as confirmatory factor analysis (CFA), exploratory structural equation modeling (ESEM), bifactor-CFA, and bifactor-ESEM (Study 2; N = 1152; Mage = 40.95), and cross-validated the optimal model (Study 3; N = 884; Mage = 38.54). We examined measurement invariance across samples and time, differential item functioning (age, body mass index [BMI], gender), composite reliability, and validity. Study 1 revealed a 12-item, 4-factor structure (unconditional permission to eat, eating for physical reasons, reliance on hunger and satiety cues, body-food choice congruence). In Study 2, a bifactor-ESEM model with a global intuitive eating factor and four specific factors best fit the data, which was temporally stable across three weeks. This model also had good fit in Study 3 and, across Studies 2 and 3, and was fully invariant and lacked measurement bias in terms of age, gender, and BMI. Associations between latent IES-3 factors and age, gender, and BMI were invariant across Studies 2 and 3. Composite reliability and validity (relationships with disordered eating, embodiment, body image, well-being, and distress; negligible relationship with impression management) of the retained model were also supported. The 12-item IES-3 demonstrates strong psychometric properties in U.S. community adults. Research is now needed using the IES-3 in other cultural contexts and social identity groups.

Identifying factors that predict the onset and persistence of fasting for weight control: Prospective findings.

OBJECTIVE: Fasting for weight control is an under-studied behaviour implicated in eating disorders. However, little is known about what factors account for its onset and persistence. METHOD: This study sought to identify risk and maintenance factors for fasting among 1025 women recruited through an eating disorder self-help platform who completed study measures at baseline and 6 month follow-up. Univariate and multivariate logistic regressions were performed to test which variables at baseline predicted the onset (vs. stably asymptomatic) and persistence (vs. remission) of fasting at follow-up. RESULTS: Univariate models showed that higher baseline overvaluation, dissatisfaction, fear of weight gain, generalised and social anxiety, depression, self-esteem deficits and eating disorder symptoms (inflexible eating rules, driven exercise) predicted greater likelihood of fasting onset. Only fear of weight gain and depressive symptoms remained significant in the multivariate model. Higher baseline overvaluation, fear of weight gain, driven exercise, inflexible eating rules, and depression predicted greater likelihood of fasting persistence in univariate models. An adherence to inflexible eating rules and overvaluation remained significant in the multivariate model. CONCLUSION: Findings shed new light on factors that may account for the development and maintenance of fasting, which have implications for guiding effective interventions targeting this behaviour.

Target-user preferences, motivations, and acceptance for a dialectical behaviour therapy smartphone application for eating disorders.

PURPOSE: Evidence shows that dialectical behavioural therapy (DBT) is efficacious for eating disorders (ED), yet few people have access to specialized treatments like DBT. Translating key DBT skills for delivery via a smartphone application may broaden the dissemination of evidence-based interventions. However, prior to developing a DBT-based app, it is crucial to gather information on target-user needs and preferences. Assessing overall acceptance and identifying predictors of acceptance, informed by the UTAUT framework, is also important. This process ensures not only a demand for such an app, but also that users receive content and features tailored to their needs. METHOD: This study aimed to understand target-user preferences of DBT-based apps for EDs by assessing willingness to engage, overall acceptance levels, and preferred functionality/content delivery modes (n = 326 symptomatic participants). RESULTS: Eighty-eight percent indicated they would be willing to use a DBT-based ED app if it were available. Acceptance levels of a DBT app were high (64%), which was uniquely predicted by performance expectancy (perceptions of how beneficial an intervention is) and facilitating conditions (expectations of technological infrastructure and support in interventions) in path analysis. Content perceived as important to contain were emotion regulation techniques, tailored intervention strategies, and psychoeducation. CONCLUSION: Findings generate important information about target-user preferences of a DBT-based app for EDs, highlighting necessary design principles for apps of this kind. Level of evidence Level V, cross-sectional descriptive study.

Bidirectional relationships between muscularity-oriented disordered eating and mental health constructs: a prospective study.

Muscularity-oriented disordered eating (MODE) is a novel class of eating behaviors characterised by abnormal dietary alterations aimed towards building lean muscle. Although traditionally shown to affect men, emerging evidence suggests that increasingly more women are striving for the muscular and lean ideal, resulting in engagement of MODE behaviors. Prior research examining MODE in women is limited, yet emerging evidence from cross-sectional studies have established associations between MODE and poor mental health indices in this population. However, the temporal order of these associations in women is not yet known. Thus, the current study examined possible bi-directional associations between MODE behaviors and common mental health outcomes (depression, anxiety, loneliness). Adult women completed online study measures at baseline (Time 1 [T1]; n = 1760) and three-month follow-up (Time 2 [T2]; n = 1180). Cross-lagged panel models were computed to test for possible bi-directional relationships between MODE and the relevant mental health constructs. Findings showed that higher MODE levels at T1 significantly predicted increased depressive and anxiety symptoms (but not loneliness) at T2, and loneliness at T1 (but not depression/anxiety) significantly predicted MODE at T2. Effect sizes were small, so findings should be interpreted with this in mind. This is the first study to establish temporal relationships between MODE and mental health outcomes in adult women. Findings suggest that clinicians may benefit from inquiring about MODE behaviors for proper screening, assessment, and intervention, and potentially addressing loneliness to decrease risk of MODE.

A broad v. focused digital intervention for recurrent binge eating: a randomized controlled non-inferiority trial.

BACKGROUND: Empirically validated digital interventions for recurrent binge eating typically target numerous hypothesized change mechanisms via the delivery of different modules, skills, and techniques. Emerging evidence suggests that interventions designed to target and isolate one key change mechanism may also produce meaningful change in core symptoms. Although both 'broad' and 'focused' digital programs have demonstrated efficacy, no study has performed a direct, head-to-head comparison of the two approaches. We addressed this through a randomized non-inferiority trial. METHOD: Participants with recurrent binge eating were randomly assigned to a broad (n = 199) or focused digital intervention (n = 199), or a waitlist (n = 202). The broad program targeted dietary restraint, mood intolerance, and body image disturbances, while the focused program exclusively targeted dietary restraint. Primary outcomes were eating disorder psychopathology and binge eating frequency. RESULTS: In intention-to-treat analyses, both intervention groups reported greater improvements in primary and secondary outcomes than the waitlist, which were sustained at an 8-week follow-up. The focused intervention was not inferior to the broad intervention on all but one outcome, but was associated with higher rates of attrition and non-compliance. CONCLUSION: Focused digital interventions that are designed to target one key change mechanism may produce comparable symptom improvements to broader digital interventions, but appear to be associated with lower engagement.

Targeting dietary restraint to reduce binge eating: a randomised controlled trial of a blended internet- and smartphone app-based intervention.

BACKGROUND: Existing internet-based prevention and treatment programmes for binge eating are composed of multiple distinct modules that are designed to target a broad range of risk or maintaining factors. Such multi-modular programmes (1) may be unnecessarily long for those who do not require a full course of intervention and (2) make it difficult to distinguish those techniques that are effective from those that are redundant. Since dietary restraint is a well-replicated risk and maintaining factor for binge eating, we developed an internet- and app-based intervention composed solely of cognitive-behavioural techniques designed to modify dietary restraint as a mechanism to target binge eating. We tested the efficacy of this combined selective and indicated prevention programme in 403 participants, most of whom were highly symptomatic (90% reported binge eating once per week). METHOD: Participants were randomly assigned to the internet intervention (n = 201) or an informational control group (n = 202). The primary outcome was objective binge-eating frequency. Secondary outcomes were indices of dietary restraint, shape, weight, and eating concerns, subjective binge eating, disinhibition, and psychological distress. Analyses were intention-to-treat. RESULTS: Intervention participants reported greater reductions in objective binge-eating episodes compared to the control group at post-test (small effect size). Significant effects were also observed on each of the secondary outcomes (small to large effect sizes). Improvements were sustained at 8 week follow-up. CONCLUSIONS: Highly focused digital interventions that target one central risk/maintaining factor may be sufficient to induce meaningful change in core eating disorder symptoms.

The promise of single session interventions for eating disorders: Lessons to be learned from research on digital mental health. Commentary on Schleider et al. (2023).

Schleider et al. propose that single session interventions (SSIs) could be a promising path toward catalyzing innovation in the development of accessible interventions for eating disorders (EDs). In this commentary, we contend that the arguments made by Schleider et al. raise many unresolved questions that continue to arise in the broader field. Drawing from our experiences with-and lessons learned from-developing, evaluating, and disseminating digital health interventions, we discuss four key empirical questions that should be addressed in order to realize the full potential of SSIs and other innovations in intervention delivery. These include: (i) for whom do we deliver an SSI; (ii) what are the optimal treatment mechanisms to target; (iii) what constitutes a "good" outcome; and (iv) where and how might we embed innovations like these. The SSI approach is a fruitful area of research enquiry, and we hope that this commentary generates further discussion and high-quality, collaborative work related to improving treatment accessibility and clinical outcomes among people with EDs.

Predictors, mediators, and moderators of response to digital interventions for eating disorders: A systematic review.

OBJECTIVE: Digital interventions show promise as an effective prevention or self-management option for eating disorders (EDs). However, it remains unclear how, for whom, and through what mechanisms they work in this population, as a synthesis of outcome predictors, moderators, and mediators is lacking. This systematic review synthesized empirical research investigating predictors, mediators, and moderators of response to digital interventions for EDs. METHOD: Six databases were searched (PROSPERO CRD42022295565) for studies that assessed predictors, moderators, or mediators of response (i.e., uptake, drop-out, engagement, and symptom level change) to a digital prevention or treatment program for EDs. Variables were grouped into several overarching categories (demographic, symptom severity, psychological, etc.) and were synthesized qualitatively across samples without a formally diagnosed ED (typically prevention-focused) and samples with a formally diagnosed ED (typically treatment-focused). RESULTS: Eighty-six studies were included. For studies recruiting samples without a formal diagnosis (n = 70 studies), most predictors explored were statistically unrelated to outcome, although participant age, baseline symptom severity, confidence to change, motivation, and program engagement showed preliminary evidence of prognostic potential. No robust moderators or mediators were identified. Few studies recruiting samples with a formal diagnosis emerged (n = 16), of which no reliable predictors, moderators, or mediators were identified. DISCUSSION: It remains unclear how, for whom, and under what circumstances digital programs targeting EDs work. We offer several recommendations for future research with the aim of advancing understanding of client characteristics and intervention elements that signal success from this intervention modality. PUBLIC SIGNIFICANCE: Digital interventions have shown potential as an effective, scalable, and accessible intervention option for EDs. However, responsiveness varies, so advancing understanding of predictors, mediators, and moderators of outcome to digital interventions for EDs is needed. Such knowledge is important for enabling safe and efficient treatment matching, and for informing future development of effective digital interventions.

OBJETIVO: Las intervenciones digitales se muestran prometedoras como una opción eficaz de prevención o autocontrol de los trastornos de la conducta alimentaria (TCA). Sin embargo, sigue sin estar claro cómo, para quién y a través de qué mecanismos funcionan en esta población, ya que falta una síntesis de los predictores de resultados, moderadores y mediadores. Esta revisión sistemática sintetiza la investigación empírica que estudia los predictores, mediadores y moderadores de la respuesta a las intervenciones digitales para los TCA. MÉTODO: Se realizaron búsquedas en seis bases de datos (CRD42022295565) de estudios que evaluaron predictores, moderadores o mediadores de la respuesta (es decir, admisión, abandono, compromiso y cambio en el nivel de síntomas) a un programa digital de prevención o tratamiento de los TCA. Las variables se agruparon en varias categorías generales (demográficas, gravedad de los síntomas, psicológicas, etc.) y se sintetizaron cualitativamente en muestras sin un TCA diagnosticado formalmente (normalmente centradas en la prevención) y muestras con un TCA diagnosticado formalmente (normalmente centradas en el tratamiento). RESULTADOS: Se incluyeron 86 estudios. Para los estudios que reclutaron muestras sin un diagnóstico formal (n = 70 estudios), la mayoría de los predictores explorados no estaban estadísticamente relacionados con el resultado, aunque la edad del participante, la gravedad de los síntomas basales, la confianza en el cambio, la motivación y el compromiso con el programa mostraron evidencia preliminar de potencial pronóstico. No se identificaron moderadores o mediadores sólidos. Surgieron pocos estudios que reclutaran muestras con un diagnóstico formal (n = 16), de los cuales no se identificaron predictores, moderadores o mediadores fiables. DISCUSIÓN: Sigue sin estar claro cómo, para quién y en qué circunstancias funcionan los programas digitales dirigidos a los TCA. Ofrecemos varias recomendaciones para futuras investigaciones con el objetivo de avanzar en la comprensión de las características de los consultantes y los elementos de intervención que señalan el éxito de esta modalidad de intervención.

Psychotherapy appears to improve symptoms of functional dyspepsia and anxiety: systematic review with meta-analysis.

This systematic review and meta-analysis examined the efficacy of psychotherapy on symptoms of functional dyspepsia, anxiety, depression and quality of life. We searched Medline, Embase, PsycINFO, Emcare, Ovid Nursing, CINAHL, Cochrane Library, Informit Health Collection and ClinicalTrials.gov on 2 July 2021. Randomised controlled trials that compared psychotherapy to non-psychotherapy interventions in adults with functional dyspepsia were included. Meta-analyses were conducted (using Hedges's g) under random effects models. Overall, 1,575 records were identified after duplicates were removed, with nine randomised controlled trials (n = 786) included. Preliminary meta-analyses showed that psychotherapy outperformed control conditions at post-test and follow-up on functional dyspepsia symptom severity and anxiety symptoms, but no differences emerged for depressive symptoms. The qualitative synthesis showed psychotherapy's promise in improving quality of life in functional dyspepsia. Psychotherapy might have a small to moderate effect on functional dyspepsia symptoms and anxiety at short- and long-term. However, conclusions are limited by the small number of trials with a high risk of bias.

Longitudinal association between self-compassion and intuitive eating: Testing emotion regulation and body image flexibility as mediating variables.

OBJECTIVES: Growing evidence suggests that intuitive eating is associated with numerous positive mental health and well-being constructs. Understanding factors that predict intuitive eating is necessary for identifying practical targets to enhance this style of eating, yet research identifying such predictors is scarce. Self-compassion is one variable that could enhance intuitive eating because it involves the practice of healthy emotion regulation skills that may disrupt the tendency to turn to food to cope during distressing situations. The present study tested for a longitudinal association between self-compassion and intuitive eating. We also tested whether this association was mediated by indices of emotion regulation (i.e., global emotion regulation skill scores and body image flexibility). METHOD: Adult women (n = 3039) were invited to completed study measures at baseline (T1), 4-month follow-up (T2), and 8-month follow-up (T3). Path analyses were computed to test hypothesized indirect effects. RESULTS: A direct path from T1 self-compassion to T3 intuitive eating emerged, such that higher self-compassion levels predicted increased intuitive eating over time. However, this association was not mediated by T2 emotion regulation skills nor body image flexibility. CONCLUSION: Findings suggest that self-compassion may facilitate an intuitive eating style, which does not appear to be explained by certain emotion regulation skills.

Investigating longitudinal bidirectional associations between appearance comparisons to fitspiration content on Instagram, positive and negative body image, and dietary restraint.

This study tested whether appearance comparisons to fitspiration images on Instagram are reciprocally associated with positive body image, negative body image, and dietary restraint. Adult women were invited to complete study measures at the baseline (n = 3039), 4-month (n = 1453), and 8-month (n = 1329) follow-up. Cross-lagged panel analyses were computed to test hypothesized bidirectional relationships using full information maximum likelihood to handle missing data. Results identified a unidirectional relationship between positive body image and fitspiration comparisons: higher positive body image (body appreciation) predicted lower fitspiration comparisons at each time-point. Evidence for bidirectional associations between fitspiration comparisons, negative body image and dietary restraint was also found. Higher negative body image and dietary restraint predicted greater fitspiration comparisons, and higher fitspiration comparisons predicted greater negative body image and dietary restraint. The findings identify factors associated with appearance-related fitspiration comparisons. Social media literacy programs may benefit from addressing comparisons to fitspiration content depicted on Instagram.

The independent contribution of muscularity-oriented disordered eating to functional impairment and emotional distress in adult men and women.

Muscularity-oriented disordered eating (MODE) refers to a broad cluster of pathological eating patterns driven by the pursuit of muscularity and leanness. Although increasing attention has been devoted towards understanding these symptoms in men, little work has been conducted to understand MODE in women. It is also unclear whether MODE contributes unique variance to functional impairment and emotional distress beyond thinness-oriented disordered eating symptoms. We addressed these gaps in a sample of 1,321 community-based adult women (n = 1136) and men (n = 185). Hierarchical multiple regressions revealed that MODE explained a significant proportion of unique variance in functional impairment in both men and women, even after controlling for traditional thinness-oriented disordered eating symptoms. MODE also contributed unique variance in symptoms of depression and anxiety in women, but not for men. Findings highlight the possible significance of these unique symptoms patterns geared towards the pursuit of muscularity and leanness. MODE symptoms may be a viable target in eating disorder intervention or prevention programs, although further longitudinal research is needed.

Efficacy of a transdiagnostic cognitive-behavioral intervention for eating disorder psychopathology delivered through a smartphone app: a randomized controlled trial.

BACKGROUND: Although effective treatments exist for diagnostic and subthreshold-level eating disorders (EDs), a significant proportion of affected individuals do not receive help. Interventions translated for delivery through smartphone apps may be one solution towards reducing this treatment gap. However, evidence for the efficacy of smartphones apps for EDs is lacking. We developed a smartphone app based on the principles and techniques of transdiagnostic cognitive-behavioral therapy for EDs and evaluated it through a pre-registered randomized controlled trial. METHODS: Symptomatic individuals (those who reported the presence of binge eating) were randomly assigned to the app (n = 197) or waiting list (n = 195). Of the total sample, 42 and 31% exhibited diagnostic-level bulimia nervosa and binge-eating disorder symptoms, respectively. Assessments took place at baseline, 4 weeks, and 8 weeks post-randomization. Analyses were intention-to-treat. The primary outcome was global levels of ED psychopathology. Secondary outcomes were other ED symptoms, impairment, and distress. RESULTS: Intervention participants reported greater reductions in global ED psychopathology than the control group at post-test (d = -0.80). Significant effects were also observed for secondary outcomes (d's = -0.30 to -0.74), except compensatory behavior frequency. Symptom levels remained stable at follow-up. Participants were largely satisfied with the app, although the overall post-test attrition rate was 35%. CONCLUSION: Findings highlight the potential for this app to serve as a cost-effective and easily accessible intervention for those who cannot receive standard treatment. The capacity for apps to be flexibly integrated within current models of mental health care delivery may prove vital for addressing the unmet needs of people with EDs.

An exploratory application of machine learning methods to optimize prediction of responsiveness to digital interventions for eating disorder symptoms.

OBJECTIVE: Digital interventions show promise to address eating disorder (ED) symptoms. However, response rates are variable, and the ability to predict responsiveness to digital interventions has been poor. We tested whether machine learning (ML) techniques can enhance outcome predictions from digital interventions for ED symptoms. METHOD: Data were aggregated from three RCTs (n = 826) of self-guided digital interventions for EDs. Predictive models were developed for four key outcomes: uptake, adherence, drop-out, and symptom-level change. Seven ML techniques for classification were tested and compared against the generalized linear model (GLM). RESULTS: The seven ML methods used to predict outcomes from 36 baseline variables were poor for the three engagement outcomes (AUCs = 0.48-0.52), but adequate for symptom-level change (R2  = .15-.40). ML did not offer an added benefit to the GLM. Incorporating intervention usage pattern data improved ML prediction accuracy for drop-out (AUC = 0.75-0.93) and adherence (AUC = 0.92-0.99). Age, motivation, symptom severity, and anxiety emerged as influential outcome predictors. CONCLUSION: A limited set of routinely measured baseline variables was not sufficient to detect a performance benefit of ML over traditional approaches. The benefits of ML may emerge when numerous usage pattern variables are modeled, although this validation in larger datasets before stronger conclusions can be made.

A systematic scoping review of research on COVID-19 impacts on eating disorders: A critical appraisal of the evidence and recommendations for the field.

OBJECTIVE: Research investigating the effects of COVID-19 on eating disorders is growing rapidly. A comprehensive evaluation of this literature is needed to identify key findings and evidence gaps to better inform policy decisions related to the management of eating disorders during and after this crisis. We conducted a systematic scoping review synthesizing and appraising this literature. METHOD: Empirical research on COVID-19 impacts on eating disorder severity, prevalence, and demand for treatment was searched. No sample restrictions were applied. Findings (n = 70 studies) were synthesized across six themes: (a) suspected eating disorder cases during COVID-19; (b) perceived pandemic impacts on symptoms; (c) symptom severity pre versus during the pandemic; (d) pandemic-related correlates of symptom severity; (e) impacts on carers/parents; and (f) treatment experiences during COVID-19. RESULTS: Pandemic impacts on rates of probable eating disorders, symptom deterioration, and general mental health varied substantially. Symptom escalation and mental health worsening during-and due to-the pandemic were commonly reported, and those most susceptible included confirmed eating disorder cases, at-risk populations (young women, athletes, parent/carers), and individuals highly anxious or fearful of COVID-19. Evidence emerged for increased demand for specialist eating disorder services during the pandemic. The forced transition to online treatment was challenging for many, yet telehealth alternatives seemed feasible and effective. DISCUSSION: Evidence for COVID-19 effects is mostly limited to participant self-report or retrospective recall, cross-sectional and descriptive studies, and samples of convenience. Several novel pathways for future research that aim to better understand, monitor, and support those negatively affected by the pandemic are formulated.

OBJETIVO: La investigación que se hace sobre los efectos de COVID-19 en los trastornos de la conducta alimentaria está creciendo rápidamente. Se necesita una evaluación exhaustiva de esta literatura para identificar los hallazgos clave y evidenciar las brechas para informar mejor las decisiones de políticas públicas relacionadas con el manejo de los trastornos de la conducta alimentaria durante y después de esta crisis. Se realizó una revisión sistemática del alcance que sintetizó y valoró esta literatura. MÉTODO: Se buscó investigación empírica sobre los impactos de COVID-19 en la gravedad, prevalencia y demanda de tratamiento de los trastornos de la conducta alimentaria. No se aplicaron restricciones a la muestra. Los hallazgos (n = 70 estudios) se sintetizaron en seis temas: (1) casos sospechosos de trastornos de la conducta alimentaria durante COVID-19; (2) impacto percibido en los síntomas; (3) gravedad de los síntomas antes versus durante la pandemia; (4) correlatos relacionados con la pandemia de la gravedad de los síntomas; (5) impactos en los cuidadores/padres; (6) experiencias de tratamiento durante COVID-19. RESULTADOS: El impacto de la pandemia en las tasas de probables trastornos de la conducta alimentaria, deterioro de los síntomas y salud mental en general variaron sustancialmente. La escala de síntomas y el empeoramiento de la salud mental durante y debido a la pandemia fueron reportados comúnmente, y los más susceptibles incluyeron casos confirmados de trastornos de la conducta alimentaria, poblaciones en riesgo (mujeres jóvenes, atletas, padres / cuidadores) e individuos con altos niveles de ansiedad o con miedo de COVID-19. Surgió alguna evidencia de una mayor demanda de servicios especializados en trastornos de la conducta alimentaria durante la pandemia. La transición forzada al tratamiento en línea fue un desafío para muchos, sin embargo, las alternativas de telesalud parecían factibles y efectivas. Conclusiones. La evidencia de los efectos de COVID-19 se limita principalmente al autoinforme de los participantes o al recuerdo retrospectivo, los estudios transversales y descriptivos, y las muestras de conveniencia. Se formulan varias vías novedosas para futuras investigaciones que tienen como objetivo comprender, monitorear y apoyar mejor a aquellos que fueron afectados negativamente por la pandemia.