Subtypes of exercise are differentially associated with baseline eating disorder pathology and treatment outcome among individuals with bulimia nervosa.

OBJECTIVE: Individuals with bulimia nervosa (BN) engage in both maladaptive (i.e., compulsive and/or compensatory) and adaptive exercise (e.g., for enjoyment). No research has examined whether those who engage in adaptive, compulsive, and/or compensatory exercise exhibit differences in BN pathology or treatment outcome compared to those not engaging in exercise, limiting intervention efficacy. METHOD: We examined associations of baseline exercise engagement with baseline and posttreatment BN pathology among 106 treatment-seeking adults (Mage = 37.4, SDage = 12.95, 87.74% female, 68.87% White) enrolled across four clinical trials of outpatient enhanced cognitive behavioral therapy for BN (range: 12-16 sessions). Analysis of covariances examined associations between baseline exercise type and baseline/posttreatment global eating pathology, dietary restraint, loss-of-control (LOC) eating, and purging frequency. RESULTS: Those engaging in only adaptive exercise reported lower global eating pathology compared to those engaging in compulsive-only exercise (Est = -1.493, p = .014, Mdiff = -.97) while those engaging in baseline compulsive exercise reported less LOC eating compared to those not engaging in exercise (Est = -22.42, p = .012, Mdiff = -12.50). Baseline engagement in compulsive-only exercise was associated with lower posttreatment global eating pathology compared to baseline engagement in no exercise (Est = -.856, p = .023, Mdiff = -.64) and both compulsive and compensatory exercise (Est = .895, p = .026, Mdiff = -1.08). DISCUSSION: Those engaging in compulsive, compensatory, adaptive, and no exercise exhibit different patterns and severity of BN pathology. Future research is needed to position treatments to intervene on maladaptive, while still promoting adaptive, exercise. PUBLIC SIGNIFICANCE STATEMENT: No research to date has examined whether those who engage in adaptive, compulsive, and/or compensatory exercise exhibit differences in BN pathology or treatment outcome compared to those not engaging in exercise, limiting targeted intervention efforts. We found that those engaging in compulsive, compensatory, and adaptive exercise exhibit different patterns of BN pathology and that adaptive exercise engagement was related to lower cognitive eating disorder symptoms at baseline.

A naturalistic examination of feeling fat: Characteristics, predictors, and the relationship with eating disorder behaviors.

OBJECTIVE: Although literature implicates feeling fat in the maintenance of binge-spectrum eating disorders (EDs; e.g., bulimia nervosa, binge-ED), research in this area is small, nascent, and relies on retrospective self-report. The current study sought to understand the temporal pattern of feeling fat and its role as a precipitant and consequence of ED behaviors. METHODS: Totally 106 treatment-seeking adults with binge-spectrum EDs completed 7-14-day ecological momentary assessments. They rated feeling fat, negative affect states, and reported on ED behaviors six times per day. Multilevel models evaluated whether feeling fat mediates prospective links between negative affect states and ED behaviors, assessed if negative affect states mediate the prospective association of feeling fat on ED behaviors, and examined the bidirectional prospective association between feeling fat and ED behaviors. RESULTS: Feeling fat was highest in the early morning (6-8:59 a.m.). Individuals with binge-ED-spectrum EDs demonstrated greater variability in feeling fat than those with bulimia nervosa-spectrum EDs who had stable and high levels of feeling fat. Guilt, sadness, anxiety, and the overall NA at Time 2 mediated the prospective associations between at Time 1 feeling fat and Time 3 dietary restraint, actual dietary restriction, and compensatory exercise. There was a bidirectional prospective association between feeling fat and binge eating. DISCUSSION: Feeling fat serves as a proximal predictor and mediator of the prospective association between guilt and binge eating. Feeling fat and binge eating mutually reinforce each other. PUBLIC SIGNIFICANCE: Little is understood regarding the experience of feeling fat in natural environments among individuals with binge-spectrum eating disorders. We found that the risk for having the experience of feeling fat is high in the morning and evening. Feeling fat triggers guilt, anxiety, and sadness which in turn, increases engagement in dietary restraint/restriction and compensatory exercise. Feeling fat also triggers binge eating, and binge eating leads to feelings of fatness.

Working out measurement overlap in the assessment of maladaptive exercise.

OBJECTIVE: Although exercise is generally considered healthy, many individuals engage in maladaptive exercise (e.g., compulsive in nature). Several definitions of maladaptive exercise exist, leading to multiple, varied assessment tools; assuming homogeneity across these assessments contributes to low consensus in etiological models. METHOD: We used a Jaccard Index to quantify content overlap among 15 commonly-used self-report instruments measuring maladaptive exercise, with 31 features identified across 224 items. RESULTS: The most common features were exercise to control weight/shape and to avoid negative affect (both included in 9/15 instruments), or compensate for calories consumed (8/15 instruments). Overlap among instruments was low (.206) and no features were common across all instruments. CONCLUSIONS: Findings generally support theoretical models of exercise in eating pathology. However, instruments most commonly used to assess maladaptive exercise measure heterogenous content. Careful consideration should be taken when comparing findings derived from differing instruments, when synthesizing literature on maladaptive exercise, and when selecting instruments to measure specific maladaptive exercise features. PUBLIC SIGNIFICANCE: Many, varied, tools exist for the assessment of maladaptive exercise (e.g., compulsive or compensatory) in the context of eating disorders. Assuming homogeneity across tools contributes to low consensus in the field. We used a Jaccard Index to quantify content overlap among 15 self-report instruments measuring maladaptive exercise. The most commonly used instruments measure heterogenous content. Careful consideration should be taken when synthesizing literature and selecting instruments to use in research.

A preliminary study of latent trajectories of change in dietary restraint during CBT-E for bulimia-spectrum eating disorders and their associations with treatment response.

OBJECTIVE: Dietary restraint is a primary target of CBT-E. However, little research has examined how specific types of dietary restraint change during CBT-E for bulimia-spectrum eating disorders (BN-EDs) or the association between changes in dietary restraint and treatment response. This study examined latent trajectories of change in eating enough, eating a range of macronutrients, and following dietary rules during CBT-E for BN-EDs and the relationships between these trajectories and pre- to post-treatment change in BN symptoms and remission. METHOD: Participants were 56 adults with BN-EDs who received 16 sessions of CBT-E and completed the Eating Disorder Examination and ecological momentary assessments (EMA) of eating behaviors and BN symptoms. Latent growth mixture modeling identified trajectories of change in dietary restraint, which were compared on pre- to post-treatment BN symptom change and remission. RESULTS: Three trajectories of change were identified for eating enough, eating a range of macronutrients, and food rules. Trajectories of change in eating enough were differentially associated with pre- to post-treatment change in BN symptoms, and trajectories of change in eating a range of macronutrients and food rules were differentially associated with remission. CONCLUSIONS: CBT-E yields heterogeneous trajectories of change in dietary restraint, which are associated with treatment response.

Identifying mechanistic links between sleep disturbance and binge eating: the role of depressed mood.

Global sleep disturbance is robustly linked with a subjective sense of loss-of-control over eating (LOC). Depressed mood has been proposed as a mechanism to explain the bi-directional relationship between sleep disturbance and LOC eating. The current study evaluated whether sleep disturbance indirectly affects LOC eating via depressed mood. Adults seeking treatment for a DSM-5 binge-spectrum eating disorder (e.g. bulimia nervosa, binge-eating disorder) were recruited (n = 79) and asked to complete self-report questionnaires assessing sleep disturbance and depression, and a semi-structured interview assessing LOC eating. Tests of indirect effects evaluated the effect of depressed mood on the association between global sleep disturbance and LOC frequency covarying for BMI and parent study. A significant indirect effect of depressed mood on the association between global sleep disturbance and frequency of LOC eating was identified (Est = 1.519, S.E. = 0.859, p = .033). The indirect effect of depressed mood on the association between sleep disturbance and LOC eating may indicate that depressed mood serves as a mechanistic link between sleep disturbance and LOC eating. The findings offer preliminary support for adjunctive treatments targeting both sleep disturbance and depressed mood for LOC eating. Future research should explore these pathways in a larger clinical sample.

Divergent trajectories of positive affect following maladaptive and non-maladaptive exercise among individuals with binge-spectrum eating disorders.

OBJECTIVE: Individuals with eating disorders (EDs) often engage in maladaptive exercise (e.g., feeling driven, or to "compensate" for eating) which maintains eating pathology. Maladaptive exercise has been theorized to help individuals with EDs regulate emotions by enhancing positive affect (PA) and reducing negative affect (NA) associated with binge episodes and poor body image. However, no research has considered the presence of non-maladaptive exercise or evaluated this theory in binge-spectrum EDs. METHODS: This study evaluated affective trajectories pre- and post-exercise and examined exercise type (maladaptive or non-maladaptive) as a moderator. We recruited adults with binge-spectrum EDs (N = 107; n = 84 endorsed exercise) to complete a 7- to 14-day ecological momentary assessment protocol assessing NA (anxiety, guilt, and sadness), PA (excitement and cheerfulness), and exercise. RESULTS: There was a significant quadratic trajectory of PA pre-exercise, suggesting that the upward trajectory of PA leveled out as it moved closer to an exercise episode. Exercise type significantly moderated the cubic trajectory of PA post-exercise, such that the upward trajectory of PA accelerated in the hours following non-maladaptive exercise episodes while the downward trajectory of PA accelerated in the hours following maladaptive exercise episodes. No trajectories of NA demonstrated significant effects. CONCLUSIONS: Pre-exercise trajectories of PA may reflect positive expectancies around exercise. Post-exercise trajectories of PA suggest that non-maladaptive exercise promotes increased PA. Future research should evaluate when, and for whom, exercise serves to regulate affect and examine other momentary risk factors of exercise in EDs. PUBLIC SIGNIFICANCE: Individuals with EDs often engage in maladaptive exercise (e.g., feeling driven, or to "compensate" for eating). Maladaptive exercise has been theorized to help individuals with EDs regulate emotions. This study evaluated affective trajectories pre- and post-exercise and examined whether exercise type (maladaptive or non-maladaptive) changed these trajectories. Pre-exercise trajectories of PA may reflect positive expectancies around exercise. Post-exercise trajectories of PA suggest that non-maladaptive exercise promotes increased PA.

Differentiating types of dietary restraint and their momentary relations with loss-of-control eating.

OBJECTIVE: Despite evidence supporting the link between dietary restraint (i.e., attempts at dietary restriction) and loss of control (LOC) eating among individuals with binge-spectrum eating disorders (EDs), some research suggests that dietary restraint may not be linked to LOC eating in all contexts. It is currently unknown how often dietary restraint results in successful dietary restriction, or which types of restraint/restriction confer highest risk for LOC eating. Furthermore, little research has evaluated momentary, temporal associations between dietary restraint and LOC eating. Thus, the present study aimed to (1) characterize dietary restraint and restriction, among individuals with LOC eating, and (2) examine temporal relationships between restraint/restriction and LOC eating within- and between-subjects. METHOD: The current study recruited adults with binge spectrum EDs (n = 96, 80.4% female) to complete a 7-14-day ecological momentary assessment protocol assessing ED symptoms. Multilevel models and linear regression evaluated within- and between-subjects associations between momentary restraint/restriction and LOC eating, respectively. RESULTS: Attempted avoidance of enjoyable foods, limiting the amount eaten, and any restraint predicted greater likelihood of LOC eating at the next survey. Attempts to delay eating predicted reduced likelihood of LOC eating at the next survey, though this effect was no longer statistically significant after correcting for multiple comparisons. Diagnostic presentation moderated the association between attempted avoidance of enjoyable foods and LOC eating such that this association was significantly stronger for those on the BN-spectrum. DISCUSSION: Dietary restraint seems to be more predictive of LOC eating than dietary restriction both within- and between-subjects. Future treatments should target dietary restraint to reduce LOC eating. PUBLIC SIGNIFICANCE: Some research suggests that dietary restriction (i.e., reduced calorie intake) and restraint (i.e., attempted restriction) may not be linked to LOC eating in all contexts. We found that dietary restraint is more predictive of LOC eating than dietary restriction both within and between individuals. Future treatments should target dietary restraint to reduce LOC eating.

Affective profiles of exercise episodes are associated with maladaptive and adaptive motivations for exercise.

OBJECTIVE: Maladaptive exercise (i.e., driven and/or compensatory exercise) is common in binge-spectrum eating disorders (EDs; e.g., bulimia nervosa, binge ED) and associated with adverse treatment outcomes. Alternatively, individuals with EDs are often also engaging in adaptive exercise (e.g., for enjoyment or health improvement), and increasing adaptive exercise may decrease ED symptoms. The current study aimed to understand which exercise episodes are likely to be maladaptive/adaptive so that interventions can appropriately decrease/increase maladaptive and adaptive exercise. METHOD: We used latent profile analysis (LPA) to identify pre-exercise affective profiles of 661 exercise episodes among 84 individuals with binge-spectrum EDs and examined associations between LPA-identified profiles and subsequent exercise motivations using ecological momentary assessment. RESULTS: A two-profile solution best fit our data: Profile 1 (n = 174), 'positive affectivity,' and Profile 2 (n = 487), 'negative affectivity.' Episodes in the 'negative affectivity' profile were more likely to be endorsed as both driven and intended to influence body shape/weight. Episodes in the 'positive affectivity' profile were more likely to be endorsed as exercising for enjoyment. CONCLUSIONS: Results support two phenotypes of exercise episodes, and differential associations of these phenotypes with adaptive and maladaptive motivations for exercise.

Latent profiles of dietary restraint among individuals with binge-spectrum eating disorders: Associations with eating disorder symptom severity.

OBJECTIVE: The relationship of dietary restraint in increasing risk for binge eating among individuals with binge-spectrum eating disorders (B-EDs) is well established. However, previous research has not yet identified whether these individuals exhibit heterogeneous profiles of dietary restraint and whether these profiles are associated with differences in eating pathology. METHODS: Individuals with B-EDs (N = 290) completed the Eating Disorder Examination. Latent profile analysis was conducted on dietary restraint frequency data, including restriction of overall amount of food consumed, avoidance of eating, desire for an empty stomach, food avoidance, and dietary rules. Identified latent profiles were compared on binge eating frequency, compensatory behaviors frequency, and ED pathology using the three-step procedure. RESULTS: A four-class model of dietary restraint best fit the data. Classes significantly differed in frequency of compensatory behaviors (F[3, 286] = 31.01, p < .001), EDE Eating Concern (F[3, 286] = 14.36, p < .001), EDE Shape Concern (F[3, 286] = 7.06, p < .001), EDE Weight Concern (F[3, 286] = 6.83, p < .001), and ED Pathology (F[3, 286] = 12.86, p < .001), but did not differ in frequency of objective (F[3, 286] = 2.45, p = .06) or subjective binge episodes (F[3, 286] = 1.87, p = .14). DISCUSSION: Individuals with B-EDs exhibit distinct profiles of dietary restraint, which are associated with frequency of compensatory behaviors and severity of ED pathology. PUBLIC SIGNIFICANCE STATEMENT: Individuals with binge-spectrum eating disorders have different patterns of restrictive eating symptoms. These profiles of restrictive eating behaviors are associated with differences in severity of compensatory behaviors and cognitive eating disorder symptoms, like shape and weight dissatisfaction. Understanding the relationships between profiles of restrictive eating behaviors and other eating disorder symptoms may allow for personalization of treatment and improvements in treatment efficacy.

Sensor technology in eating disorders research: A systematic review.

OBJECTIVE: Sensor technologies offer exciting potential to objectively measure psychopathological correlates of eating pathology and eating disorder (ED) research utilizing sensors has rapidly proliferated in the past several years. The aims of the present review are: (1) characterize the types of sensors that have been utilized in ED research, (2) identify the psychopathological factors relevant to EDs that have been assessed using sensors, (3) describe the data supporting the validity and reliability of these sensors, (4) discuss limitations associated with these sensors, and (5) identify gaps that persist within the ED literature with regard to use of sensor technologies. METHOD: A systematic search was conducted of PubMed, PsycINFO, Web of Science, ProQuest, and "gray" literature sources. Eligible publications were empirical studies that utilized sensors to measure at least one psychological variable among clinical ED populations. RESULTS: Sensors have been utilized with ED samples to measure eating behaviors, physical activity, sleep, autonomic nervous system activity, eyeblink startle response, visual attention, and visual-haptic object integration. The reliability and validity of these sensors varies widely and there are a number of significant gaps that remain in the literature with regard to the types of sensors utilized, context in which sensors have been used, and populations studied. DISCUSSION: The existing literature utilizing sensors within ED research largely support the feasibility and acceptability of these tools. Sensors should continue to be utilized within the field, with a specific focus on examining the reliability and validity of these tools within ED samples and increasing the diversity of samples studied. PUBLIC SIGNIFICANCE STATEMENT: Sensor technologies, such as those included in modern smartwatches, offer new opportunities to measure factors that may maintain or contribute to symptoms of eating disorders. This article describes the types of sensors that have been used in eating disorders research, challenges that may arise in using these sensors, and discusses new applications of these sensors that may be pursued in future research.

Momentary associations between fear of weight gain and dietary restriction among individuals with binge-spectrum eating disorders.

OBJECTIVE: Fear of weight gain (FOWG) is increasingly implicated in the maintenance of binge-spectrum eating disorders (EDs; e.g., bulimia nervosa [BN], binge-eating disorder [BED]) through the pathway of increased dietary restriction. However, particularly in binge-spectrum EDs, research is nascent and based on retrospective self-report. To improve treatment outcomes, it is critical to better understand the momentary relations between FOWG and dietary restriction. METHOD: Sixty-seven adults with binge spectrum EDs completed a 7-14-day ecological momentary assessment protocol that included items regarding FOWG, ED behaviors, and types of dietary restriction (e.g., attempted restraint vs. actual restriction) several times per day. Multilevel models were used to evaluate reciprocal associations between FOWG and dietary restriction, and to evaluate the indirect of effects of dietary restriction on the relation between FOWG and binge eating. RESULTS: While main effects were not statistically significant, ED presentation significantly moderated the association between increases in FOWG at time1 and both attempted and actual avoidance of enjoyable foods at time2 such that those with BN-spectrum EDs were more likely to avoid enjoyable foods following increased FOWG compared to those with BED-spectrum EDs. Engagement in restriction at time1 was not associated with decreased FOWG at time2. DISCUSSION: Prospective associations between FOWG and restriction suggest that individuals with BN may be more likely to restrict their eating following increased FOWG. These findings suggest FOWG may be an important target for future treatments.

Associations between emotion regulation and remission following cognitive behavioural therapy for adults with bulimia nervosa.

OBJECTIVE: Emotion regulation (ER) deficits are associated with illness severity in individuals with bulimia nervosa. We examined whether baseline ER abilities are associated with remission following enhanced cognitive behavioural therapy for eating disorders (CBT-E). METHOD: Participants (N = 50, 85.0% female) receiving CBT-E completed a measure (yielding a global score and six subscale scores) of ER pre-treatment. Remission was assessed by the Eating Disorder Examination at post-treatment and follow-up. Analyses tested associations between baseline ER and behavioural, cognitive, or full remission at post-treatment and three-month follow-up. RESULTS: Lower global ER abilities, measured by the Difficulties in Emotion Regulation Scale, were associated with lower likelihood of behavioural and full, but not cognitive, remission at post-treatment. Specifically, individuals low in emotional clarity and impulse control were less likely to be behaviourally remitted. Those low in emotional acceptance, awareness, clarity, or strategies to manage emotion were less likely to be fully remitted. Global ER scores were not associated with any remission type at follow-up. DISCUSSION: Baseline ER deficits were associated with lower likelihood of behavioural or full remission at post-treatment. However, ER was less associated with remission at follow-up, indicating that ER is most important during treatment. Findings highlight a need for targeted treatments aimed at improving ER.

Feasibility, Acceptability, and Preliminary Target Engagement of a Healthy Physical Activity Promotion Intervention for Bulimia Nervosa: Development and Evaluation via Case Series Design.

Bulimia nervosa (BN) is characterized by a pattern of binge eating and compensatory behaviors as well as an overemphasis on body weight and shape in self-evaluation. Although cognitive behavioral therapy (CBT) is efficacious, recent reviews suggest that only 30% of patients reach abstinence at posttreatment. One potential reason for these poor outcomes is that CBT fails to adequately reduce elevated negative affect (NA) and shape and weight concern, which have been shown to be correlated with poorer treatment outcomes in BN. Therefore, novel treatment components that focus on improving NA and shape and weight concern are needed in order to enhance outcomes. Promoting physical activity (PA) is a promising avenue through which to reduce NA and improve body image in healthy individuals, other clinical populations (e.g., individuals with depression or anxiety), and individuals with eating disorders. While prescribing PA for individuals with BN has been controversial (due to concerns that exercise maybe be used to compensate for binge episodes or become driven or compulsive), this approach may have many benefits, including promoting healthy lifetime exercise habits that reduce likelihood of relapse through the improvement of emotion regulation skills and weight regulation. Given the promise of PA for targeting key maintenance factors of BN, we developed a 12-session healthy PA promotion intervention for BN and tested initial feasibility, acceptability, and preliminary target engagement in an iterative case series design (n = 3). The treatment provided cognitive-behavioral skills designed to identify, practice, and achieve behavioral goals while asking patients to engage in up to 150 minutes of moderate-to-vigorous PA per week, which was preplanned during each session with the client's therapist. Results suggested that the healthy PA promotion intervention was both feasible and acceptable to deliver. In addition, the intervention resulted in a clinically significant decrease in BN symptom frequency in each participant. Further, participants showed clinically significant decreases in NA and shape and weight concern. The current study demonstrates that healthy PA interventions can have beneficial effects on BN symptoms, NA, and shape and weight concern. However, due to the small sample size, conclusions must be treated with caution. Future research should investigate additional approaches for promoting healthy PA and include a larger sample in order to further test initial efficacy of this treatment approach.

Associations between fear of weight gain and exercise in binge-spectrum eating disorders.

PURPOSE: Maladaptive exercise (i.e., exercise that is either driven or compensatory) is thought to momentarily down-regulate elevated fear of weight gain (FOWG). However, little research has examined associations between FOWG and exercise, and no research has measured FOWG at a momentary level or considered exercise type (i.e., maladaptive vs. adaptive). Thus, we examined both within- and between-subject associations between FOWG and exercise among individuals with trans-diagnostic binge eating. METHODS: We recruited treatment-seeking adults (N = 58, 82.9% female) to complete a 7-14-day ecological momentary assessment protocol which assessed levels of FOWG and exercise engagement and type. Mixed models and generalized estimating equations assessed within-subject associations, and linear regression assessed between-subject associations. RESULTS: There was no main effect of FOWG on exercise engagement at the next survey. However, unexpectedly, exercise type moderated this relationship such that the relationship between FOWG and exercise was strongest for episodes of adaptive exercise. Overall exercise frequency accounted for 10.4% of the variance in FOWG and exercise type explained an additional 1.7% of the variance in FOWG. CONCLUSION: The findings of the current study indicate that momentary levels of FOWG are associated with subsequent adaptive exercise episodes, while higher overall levels of maladaptive exercise were associated with higher levels of FOWG. Future treatments should place a greater emphasis on reducing the frequency of maladaptive exercise by providing strategies for reducing FOWG. LEVEL OF EVIDENCE: Level IV: Evidence obtained from multiple time series analysis such as case studies.

Latent trajectories of symptom change during cognitive-behavior therapy predict post-treatment worsening of symptoms: a preliminary examination among outpatients with bulimia-spectrum eating disorders.

PURPOSE: Up to 44% of individuals with bulimia nervosa (BN) experience worsening of symptoms after cognitive behavior therapy (CBT). Identifying risk for post-treatment worsening of symptoms using latent trajectories of change in eating disorder (ED) symptoms during treatment could allow for personalization of treatment to improve long-term outcomes METHODS: Participants (N = 56) with BN-spectrum EDs received 16 sessions of CBT and completed digital self-monitoring of eating episodes and ED behaviors. The Eating Disorder Examination was used to measured ED symptoms at post-treatment and 3-month follow-up. Latent growth mixture modeling of digital self-monitoring data identified latent growth classes. Kruskal-Wallis H tests examined effect of trajectory of change in ED symptoms on post-treatment to follow-up symptom change. RESULTS: Multi-class models of change in binge eating, compensatory behaviors, and regular eating improved fit over one-class models. Individuals with high frequency-rapid response in binge eating (H(1) = 10.68, p =0 .001, η2 = 0.24) had greater recurrence of compensatory behaviors compared to individuals with low frequency-static response. Individuals with static change in regular eating exhibited greater recurrence of binge eating than individuals with moderate response (H(1) = 8.99, p = 0.003, η2 = 0.20). CONCLUSION: Trajectories of change in ED symptoms predict post-treatment worsening of symptoms. Personalized treatment approaches should be evaluated among individuals at risk of poor long-term outcomes. LEVEL OF EVIDENCE: IV, evidence obtained from multiple time series. TRIAL REGISTRATION: ClinicalTrials.gov registration number NCT03673540, registration date: September 17, 2018.

Understanding momentary associations between body dissatisfaction and exercise in binge-spectrum eating disorders.

PURPOSE: Maladaptive exercise is common among individuals with binge-spectrum eating disorders. One mechanism that may drive engagement in exercise in this population is state body dissatisfaction. However, no studies to date have examined prospective, momentary relationships between state body dissatisfaction and exercise. METHODS: Adults with binge-spectrum eating disorders (N = 58) completed a 7-14-day ecological momentary assessment protocol assessing exercise and state body dissatisfaction several times per day. Multilevel models were used to evaluate prospective reciprocal associations between state body dissatisfaction and exercise. Mixed models examined trajectories of change in state body dissatisfaction pre- and post-exercise. Additional models examined exercise type (maladaptive vs. adaptive) as a moderator. RESULTS: Momentary increases (i.e., greater than one's average levels) in state body dissatisfaction at any given timepoint did not prospectively predict engagement in exercise at the next nearest timepoint. Exercise at any given timepoint did not prospectively predict momentary increases in state body dissatisfaction. State body dissatisfaction was found to increase in the initial hours preceding an exercise episode (linear estimate, ß = - 0.012, p = 0.004). State body dissatisfaction did not significantly change in the hours following engagement in exercise. Exercise type did not moderate these associations. CONCLUSION: If replicated, our results may suggest that momentary increases in state body dissatisfaction may not be associated with exercise behaviors in individuals with binge-spectrum eating disorders. LEVEL OF EVIDENCE: Level V: Opinions of authorities, based on descriptive studies, narrative reviews, clinical experience, orreports of expert committees.

An examination of daily sleep characteristics and subsequent eating disorder behavior among individuals with binge-spectrum eating disorders.

INTRODUCTION: Specific characteristics of sleep (e.g., duration, quality, and fatigue) are positively associated with (ED) behaviors, specifically binge eating (BE) potentially through decreased self-regulation and increased appetite. However, prior work has been largely cross-sectional and has not examined temporal relationships between sleep characteristics and next-day ED behaviors. Thus, the present study examined daily relationships between sleep and ED behaviors among individuals with binge-spectrum EDs. METHOD: Participants (N = 96) completed 7 daily ecological momentary assessment (EMA) surveys over 7-14 days; morning surveys assessed sleep characteristics and 6 randomly timed surveys each day captured ED behaviors. Analyses examined within-subject and between-subject effects of sleep quality, duration, and fatigue on BE, compensatory purging behaviors, and maladaptive exercise. RESULTS: Within-subject sleep quality was significantly negatively associated with engagement in maladaptive exercise later that day. Additionally, between-subject sleep duration was significantly negatively associated with engagement in compensatory purging behaviors. DISCUSSION: Within- and between-subjects associations between sleep quality and duration and compensatory behavior engagement indicate that sleep plays an important role in ED behaviors. Future research should incorporate sensor-based measurement of sleep and examine how specific facets of sleep impact BE and treatment response. LEVEL OF EVIDENCE: Level II: Evidence obtained from controlled trial without randomization.

Using virtual reality to train inhibitory control and reduce binge eating: A proof-of-concept study.

OBJECTIVE: One reason for limited efficacy of treatments for binge eating disorder (BED) and bulimia nervosa (BN) is a failure to directly target deficits in inhibitory control (i.e., the ability to withhold a pre-potent response). Inhibitory control trainings (ICTs; computerized tasks meant to improve inhibitory control) have shown promise but appear not to be powerful enough to generalize to real-word eating behavior or engaging enough for to sustain long-term compliance. Delivering an ICT through virtual reality (VR) technology should increase intervention power because 3D imagery and actual real hand/arm movements are lifelike and may improve compliance because the VR environment is highly engaging. Thus, we created the first-ever VR-based ICT to test its initial feasibility, acceptability, and impact on binge eating. METHOD: We recruited participants (N = 14) with once-weekly loss-of-control (LOC) eating to use the VR ICT daily, at home, for two weeks, and measured feasibility, acceptability and change in LOC eating at post-intervention and 2-week follow-up. RESULTS: The VR ICT was feasible to construct and deploy, and demonstrated high acceptability and compliance (i.e., 86.8% of daily trainings completed). Users of the VR ICT experienced large decreases in LOC eating at post-intervention and 2-week follow-up. DISCUSSION: Results from this initial pilot indicate that delivering ICT through VR is feasible, acceptable, and is associated with reductions in binge eating. Future study is warranted and should examine whether a VR ICT can serve as a useful adjunct to standard treatment for BN and BED.

Stress appraisal prospectively predicts binge eating through increases in negative affect.

PURPOSE: Ecological momentary assessment (EMA) studies preliminarily support the transactional model of emotion regulation in eating disorders, such that heightened stress appraisal (i.e., the cognitive evaluation of an event's demands) results in increased negative affect (NA) and subsequent binge eating (BE). However, the temporal relationships between these variables and the magnitude of stress appraisal that is clinically significant require clarification. The current study aimed to extend previous research by (1) examining the temporal relationship between stress appraisal, changes in NA, and BE using three timepoints, (2) exploring what magnitude of momentary stress appraisal results in clinically significant increases in NA and BE, and (3) characterizing what stressors are associated with clinically significant stress appraisal. METHODS: 37 adult females completed an EMA protocol assessing momentary stressors, stress appraisal, NA, and BE over 2 week duration. Multilevel mediation models were used to test the study aims. RESULTS: Momentary increases in stress appraisal significantly predicted binge eating through increases in NA. Stress appraisal ratings of 0.50 SD higher relative to one's average stress appraisal began to significantly predict the likelihood of BE through increases in NA, and the likelihood of BE occurrence increased with every 0.25 increments in momentary stress appraisal. Work/school stressors and interpersonal stressors were the most commonly endorsed stressors of clinically significant stress appraisal. CONCLUSION: The current study supported the transactional model of emotion dysregulation in a binge eating sample and supports the use of momentary interventions at times of clinically significant stress appraisal to reduce BE risk. LEVEL OF EVIDENCE: Level II, controlled trial without randomization.

The project REBOOT protocol: Evaluating a personalized inhibitory control training as an adjunct to cognitive behavioral therapy for bulimia nervosa and binge-eating disorder.

Outcomes from cognitive behavioral therapy (CBT) for bulimia nervosa (BN) and binge-eating disorder (BED) are suboptimal. One potential explanation is that CBT fails to adequately target inhibitory control (i.e., the ability to withhold an automatic response), which is a key maintenance factor for binge eating. Computerized inhibitory control training (ICT) is a promising method for improving inhibitory control but is relatively untested in BN/BED. The present study will evaluate a computer-based ICT as an adjunct to CBT for BN/BED. Participants with BN (n = 30) or BED (n = 30) will be randomized to 12 weeks of either CBT + ICT or CBT + a sham training. Trainings will be completed daily for 4 weeks and weekly for 8 weeks. Primary aims include the following: (a) confirm target engagement (evaluate whether ICT improves inhibitory control), (b) test target validation (evaluate whether improvements in inhibitory control are associated with improvements in binge eating), and (c) evaluate the incremental efficacy of ICT on binge eating. Secondary aims include the following: (a) evaluate ICT feasibility and acceptability and (b) assess the moderating effects of approach tendencies on highly palatable food, dietary restraint, and diagnosis. Data will be used to shape a fully powered clinical trial designed to assess efficacy and dose-response effects of ICT for BN/BED.