Characteristics and stability of empirically derived anorexia nervosa subtypes: towards the identification of homogeneous low-weight eating disorder phenotypes

Avoidant/Restrictive Food Intake Disorder: Review and Recent Advances

Avoidant/restrictive food intake disorder (ARFID) is an eating disorder recently codified in DSM-5 that affects individuals of all ages. A proliferation of ARFID research has emerged over the years, and this review provides a brief overview of the current understanding of ARFID epidemiology, symptoms, comorbid conditions, assessment, and treatment. The review highlights recent research updates regarding ARFID among adults, putative neurobiological mechanisms underlying ARFID, and new treatment trials. Findings from this review demonstrate that ARFID is as prevalent as other eating disorders, even among adults, and is associated with significant medical and psychiatric comorbid conditions. New, promising treatments for children, adolescents, and adults are in the early stages of development. Several assessments are now available to aid in the screening and diagnosis of ARFID and have demonstrated cross-cultural validity. Areas for future research and clinical guidance, including unresolved questions regarding ARFID categorization and differential diagnosis, are discussed.

Recovery Trajectories in Adolescent Girls with Anorexia Nervosa

Background: This study aimed to document recovery trajectories among adolescents with anorexia nervosa (AN) based on three markers of remission, namely changes in body weight, food restriction, and excessive exercise, and to identify predictors of these trajectories. Methods: One hundred twenty-six adolescent girls (14.7 ± 1.3 years) were recruited during initial assessment visits at specialized eating disorder (ED) programs in five University Health Centers across the province of Quebec, Canada. z-BMI and AN symptom severity (food restriction and excessive exercise) were assessed at initial assessment visits and subsequently reassessed at each quarterly follow-up over a 12-month period to identify recovery trajectories. Results: Considering the three markers of remission, three distinct trajectories emerged: Group 1, rapid responders; Group 2, gradual responders; and Group 3, unstable responders. At initial visits, a difference between groups was found regarding the type of treatment (p = 0.01) and weight suppression (p = 0.02). Group 1 had a higher number of youths hospitalized than Group 2 and Group 3, and a greater weight suppression than Group 3. Furthermore, individuals with atypical AN were more likely to belong to Group 2 than to Group 1 and Group 3 (p < 0.0001). Conclusions: This study contributes to a better understanding of the heterogeneity of recovery trajectories in adolescent girls with AN.

Identifying overcontrol and undercontrol personality types among young people using the five factor model, and the relationship with disordered eating behaviour, anxiety and depression

BACKGROUND

Overcontrol and undercontrol personality types have been associated with an increase in eating pathology, depression and anxiety. The aim of the research was to explore whether latent overcontrol and undercontrol personality types could be identified using cluster analysis of the facets of the five factor model (FFM). We further aimed to understand how these personality types were associated with eating pathology, depressed mood and anxiety.

METHODS

A total of 561 participants (394 women and 167 men), aged 16-30 years in Australia completed a survey designed to assess disordered eating, FFM personality traits, anxiety, depression and stress. A systematic four-step process using hierarchical, k-means, and random forest cluster analyses were used to identify a meaningful 3-cluster solution.

RESULTS

The results revealed a cluster solution that represented overcontrol, undercontrol and resilient personality types, and highlighted facets of the FFM that were associated with each type. Both overcontrol and undercontrol personality types were associated with increased clinical symptoms compared to the resilient types.

CONCLUSIONS

It was concluded that FFM facets may potentially be more meaningful than broad domains in identifying personality types, and that both overcontrol and undercontrol personality types are likely associated with increased clinical symptoms.

Exploring latent profiles of disordered eating using an indicator of dietary restriction in an undergraduate sample of men and women

OBJECTIVE

Latent class or latent profile analysis (LPA) studies in patients with eating disorders consistently identify a low-weight, restrictive eating subgroup that does not endorse weight/shape concerns. To date, similar studies in samples unselected for disordered eating symptoms have not identified a high restriction-low weight/shape concerns group, which may be due to a lack of inclusion of measures of dietary restriction.

METHOD

We conducted an LPA using data from 1623 college students (54% female) recruited across three different studies. The Eating Pathology Symptoms Inventory Body Dissatisfaction, Cognitive Restraint, Restricting, and Binge Eating subscales were used as indicators, and body mass index, gender, and dataset were covaried. Purging, excessive exercise, emotion dysregulation, and harmful alcohol use were compared across resulting clusters.

RESULTS

Fit indices supported a 10-class solution, including five disordered eating groups (largest to smallest): "Elevated General Disordered Eating", "Body Dissatisfied Binge Eating," "Most Severe General Disordered Eating," "Non-Body Dissatisfied Binge Eating," and "Non-Body Dissatisfied Restriction." The "Non-Body Dissatisfied Restriction" group scored as low on other measures of traditional eating pathology and harmful alcohol use as non-disordered eating groups but scored as high on a measure of emotion dysregulation as other disordered eating groups.

DISCUSSION

This study is the first to identify a latent restrictive eating group that does not endorse traditional disordered eating cognitions in an unselected sample of undergraduate students. Results underscore the importance of using measures of disordered eating behaviors without implied motivation to capture overlooked problematic eating patterns in the population that are distinct from our "traditional" understanding of disordered eating.

PUBLIC SIGNIFICANCE

We identified a group of individuals with high levels of restrictive eating but low body dissatisfaction and intent to diet in an unselected adult sample of men and women. Results underscore the need to investigate restrictive eating outside of the traditional lens of body shape concerns. Findings also suggest that individuals with nontraditional eating difficulties may struggle with emotion dysregulation, putting them at risk of poor psychological and relational outcomes.

Proposal for increasing diagnostic clarity in research and clinical practice by renaming and reframing atypical anorexia nervosa as "Restrictive Eating Disorder" (RED)

Atypical anorexia nervosa (AAN) in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), is characterized by meeting all criteria for anorexia nervosa (AN) except for weight being within or above the "normal" range despite significant weight loss. The current definition is plagued by several problems, resulting in widely heterogeneous operationalizations in research and clinical practice. As such, the poorly defined diagnosis of AAN negatively impacts affected individuals and frustrates research attempts to better understand the syndrome. We consider conceptual flaws in the AAN description and contend that the undefined weight range and nature of weight loss renders these two factors functionally inapplicable in research and practice. They also represent a departure from the originally intended use of the AAN category, i.e., arresting a negative weight trajectory likely to result in AN, making the target population, and the application of the label, unclear. We propose revised criteria and a new name, restrictive eating disorder (RED), intended to reduce stigma and encompass a wide but better-defined range of presentations. The RED criteria focus on clinically significant restrictive behavior that disrupts normal living (i.e., impairment), and cognitive symptoms of overevaluation, disturbed experience, and lack of recognition of illness seriousness. We believe that RED may enable more appropriate clinical application, but also inspire coordinated research toward a more valid psychiatric nosology in the eating disorders field.

Differences and similarities in personality functioning across different types of eating disorders

Objective

The classification of anorexia nervosa (AN) into subtypes is relevant due to their different symptomatology. However, subtypes (restricting type: AN-R; purging type: AN-P) differ also in terms of their personality functioning. Knowledge about these differences would allow for better treatment stratification. A pilot study indicated differences in structural abilities that can be assessed by the operationalized psychodynamic diagnosis (OPD) system. The aim of this study was therefore to systematically explore differences in personality functioning and personality between the two AN subtypes and bulimia nervosa (BN) using three personality (functioning) constructs.

Methods

A total of N = 110 inpatients with AN-R (n = 28), AN-P (n = 40), or BN (n = 42) were recruited in three clinics for psychosomatic medicine. Assignment to the three groups was performed using a comprehensive questionnaire validated for diagnostic purposes (Munich-ED-Quest). Personality functioning was examined using OPD Structure Questionnaire (OPD-SQ), personality by using the Personality Inventory for DSM-5-Brief Form and Big Five Inventory-10. (M)ANOVAs were used to examine differences across eating disorder groups. In addition, correlation and regression analyses were conducted.

Results

We observed differences on several sub- and main scales of the OPD-SQ. Whereas patients with BN showed the lowest levels, AN-R patients displayed the highest levels of personality functioning. On some sub- and main scales, such as "affect tolerance," the subtypes of AN differed from BN, whereas on the scale "affect differentiation," AN-R, differed from the other two groups. The total eating disorder pathology score of the Munich-ED-Quest best predicted overall personality structure [stand. β = 0.650; t(104) = 6.666; p < 0.001] and self-regulation [stand. β = 0.449; t(104) = 3.628; p < 0.001].

Discussion

Our findings confirm most of the results of the pilot study. These findings can facilitate the development of stratified treatment approaches for eating disorders.

Altered processing of conflicting body representations in women with restrictive anorexia nervosa

Cognitive and affective impairments in processing body image have been observed in patients with Anorexia Nervosa (AN) and may induce the hypercontrolled and regulative behaviors observed in this disorder. Here, we aimed to probe the link between activation of body representations and cognitive control by investigating the ability to resolve body-related representational conflicts in women with restrictive AN and matched healthy controls (HC). Participants performed a modified version of the Flanker task in which underweight and overweight body images were presented as targets and distractors; a classic version of the task, with letters, was also administered as a control. The findings indicated that performance was better among the HC group in the task with bodies compared to the task with letters; however, no such facilitation was observed in AN patients, whose overall performance was poorer than that of the HC group in both tasks. In the task with body stimuli, performance among patients with AN was the worst on trials presenting underweight targets with overweight bodies as flankers. These results may reflect a dysfunctional association between the processing of body-related representations and cognitive control mechanisms that may aid clinicians in the development of optimal individualized treatments.

Visualizing Emotional Arousal within the Context of Body Size Evaluation: A Pilot Study of Steady-State Visual Evoked Potentials in Women with Anorexia Nervosa and Healthy Controls

Maladaptive body size evaluation processes and body dissatisfaction are known as central risk factors for the development and maintenance of anorexia nervosa (AN). This study aimed to experimentally test potential key facets, such as (psycho)physiological, cognitive-verbal and behavioral mechanisms, within the context of these evaluation processes. Twenty-two females with AN (AN-G) and 22 healthy controls (HC-G) looked at pictures of their body gradually increasing in weight using a morphing technique. Implicit emotional arousal was assessed using steady-state visual evoked potentials (SSVEP) in electroencephalography. Additionally, in a forced-choice body size evaluation task, participants were asked to classify pictures of their own body as not big or big while reaction times were captured. A significantly earlier increase in SSVEPs emerged in AN-G compared to HC-G (p <.05), with AN-G evaluating their bodies in the morphing process as big at a significantly thinner body size (p <.05). The AN-G showed faster reaction times in the categorical evaluation of body stimuli (p <.05). Findings from this multimodal paradigm underline the importance of body size evaluation mechanisms and underlying emotional arousal for AN. A differentiated understanding of these processes is essential, since the effectiveness of therapeutic interventions for AN is limited and relapses are frequent.

Bad mood food? Increased versus decreased food cue reactivity in anorexia nervosa and bulimia nervosa during negative emotions

OBJECTIVE

Emotion regulation difficulties in anorexia nervosa (AN) and bulimia nervosa (BN) might underlie bingeing and purging in BN, extreme fasting in AN, or combinations of these symptoms in binge-purge type AN. In this study, we tested for decreased food cue reactivity in response to negative emotions in AN, and the opposite pattern for BN. Furthermore, we explored subgroup differences (restrictive vs. binge-purging AN; history of AN in BN).

METHOD

Patients with AN (n = 41), BN (n = 39), and matched controls (n = 70) completed an emotional eating questionnaire. In a laboratory experiment, we induced negative emotions and measured food cue reactivity (pleasantness, desire to eat (DTE), and corrugator muscle activity).

RESULTS

AN reported emotional undereating, while BN reported emotional overeating. In the laboratory task, BN showed increased DTE and an appetitive corrugator response during negative emotions, selectively towards high-calorie foods. AN showed generalized reduced cue reactivity to high-calorie food regardless of emotional state. This pattern appears to be characteristic of restrictive AN, while cue reactivity of both BN subgroups pointed towards emotional overeating.

CONCLUSIONS

The emotional over- versus undereating framework might help to explain bingeing and restricting along the anorectic-bulimic disorder spectrum, which calls for novel transdiagnostic theories and subgroup-specific treatments.

Mixture Modeling to Characterize Anorexia Nervosa: Integrating Personality and Eating Disorder Psychopathology

BACKGROUND: Efforts to examine alternative classifications (e.g., personality) of anorexia nervosa (AN) using empirical techniques are crucial to elucidate diverse symptom presentations, personality traits, and psychiatric comorbidities. AIMS: The purpose of this study was to use an empirical approach (mixture modeling) to test an alternative classification of AN as categorical, dimensional, or hybrid categorical-dimensional construct based on the co-occurrence of personality psychopathology and eating disorder clinical presentation. METHODS: Patients with AN (N = 194) completed interviews and questionnaires at treatment admission and 3-month follow-up. Mixture modeling was used to test whether indicators best classified AN as categorical, dimensional, or hybrid. RESULTS: A four-latent class, one-latent dimension mixture model that was variant across groups provided the best fit to the data. Results suggest that all classes were characterized by low self-esteem and self-harming and suicidality tendencies. Individuals assigned to Latent Class 2 (LC2; n = 21) had a greater tendency toward being impulsive and easily angered and having difficulties controlling anger compared with those in LC1 (n = 84) and LC3 (n = 66). Moreover, individuals assigned to LC1 and LC3 were more likely to have a poor outcome from intensive treatment compared with those in LC4 (n = 21). Findings indicate that the dimensional aspect within each class measured frequency of specific eating disorder behaviors but did not predict treatment outcomes. CONCLUSIONS: These results emphasize the complexity of AN and the importance of considering how facets of clinical presentation beyond eating disorder behaviors may have different treatment and prognostic implications.

Weight bias and linguistic body representation in anorexia nervosa: Findings from the BodyTalk project

OBJECTIVE

This study provides a comprehensive assessment of own body representation and linguistic representation of bodies in general in women with typical and atypical anorexia nervosa (AN).

METHODS

In a series of desktop experiments, participants rated a set of adjectives according to their match with a series of computer generated bodies varying in body mass index, and generated prototypic body shapes for the same set of adjectives. We analysed how body mass index of the bodies was associated with positive or negative valence of the adjectives in the different groups. Further, body image and own body perception were assessed.

RESULTS

In a German-Italian sample comprising 39 women with AN, 20 women with atypical AN and 40 age matched control participants, we observed effects indicative of weight stigmatization, but no significant differences between the groups. Generally, positive adjectives were associated with lean bodies, whereas negative adjectives were associated with obese bodies.

DISCUSSION

Our observations suggest that patients with both typical and atypical AN affectively and visually represent body descriptions not differently from healthy women. We conclude that overvaluation of low body weight and fear of weight gain cannot be explained by generally distorted perception or cognition, but require individual consideration.

Fat-Phobic and Non-Fat-Phobic Anorexia Nervosa: A Conjoint Analysis on the Importance of Shape and Weight

With the introduction of new diagnostic criteria in DSM-5, fear of weight gain no longer represents a sine qua non-criterion for the diagnosis of anorexia nervosa (AN). This is of relevance as a subgroup of individuals with AN denies fear of weight gain as the reason for restrictive eating but still remain at a very low weight. As self-reports are susceptible to bias, other methods are needed to confirm the existence of the subtype in order to provide adapted treatment. Therefore, we aimed to measure fear of weight gain using a novel method in clinical psychology, the conjoint analysis (CA). Relative importance and preference scores for various life aspects, including appearance/shape and weight were assessed in women with fat-phobic AN (FP-AN, n = 30), NFP-AN (n = 7), and healthy controls (n = 29). Individuals with FP-AN showed a significant lower preference for weight gain versus weight maintenance than HC (p = 0.011, ηp2 = 0.107). Correlation between explicitly assessed drive for thinness and CA score was low. As expected, in FP-AN the explicitly endorsed fear of weight gain was confirmed by the marked preference for weight maintenance compared to HC, while for NFP-AN explicit and implicit measures diverged, indicating that against their self-report they may experience at least some fear of weight gain. The utility of CA as a tool to measure fear of weight gain — and potentially other psychopathological constructs —requires further confirmation.

Psychological Impairment as a Predictor of Suicide Ideation in Individuals with Anorexia Nervosa

Anorexia nervosa (AN) is an eating disorder characterized by severe food restriction resulting in low body weight and an intense fear of gaining weight. This disorder has one of the highest suicide rates of any psychiatric illness; however, few studies have investigated prospective predictors of suicide ideation (SI) in this population. Quality-of-life impairment may be particularly relevant for understanding suicide risk in AN, given associations with SI in other psychiatric disorders and associations with chronicity and severity in AN. This study explored associations between eating disorder-related impairment and SI in individuals with AN (n = 113) who completed assessments at treatment discharge and 3, 6, and 12 months after discharge. Greater psychological impairment predicted future occurrence of SI controlling for age, depression, history of SI, and eating disorder variables. Associations were specific to psychological impairment as other domains of impairment did not predict SI over time. Findings highlight the potential importance of targeting interpersonal-psychological consequences of AN to decrease future suicide risk.

Medication in AN: A Multidisciplinary Overview of Meta-Analyses and Systematic Reviews

Drugs are widely prescribed for anorexia nervosa in the nutritional, somatic, and psychiatric fields. There is no systematic overview in the literature, which simultaneously covers all these types of medication. The main aims of this paper are (1) to offer clinicians an overview of the evidence-based data in the literature concerning the medication (psychotropic drugs and medication for somatic and nutritional complications) in the field of anorexia nervosa since the 1960s, (2) to draw practical conclusions for everyday practise and future research. Searches were performed on three online databases, namely MEDLINE, Epistemonikos and Web of Science. Papers published between September 2011 and January 2019 were considered. Evidence-based data were identified from meta-analyses, if there were none, from systematic reviews, and otherwise from trials (randomized or if not open-label studies). Evidence-based results are scarce. No psychotropic medication has proved efficacious in terms of weight gain, and there is only weak data suggesting it can alleviate certain psychiatric symptoms. Concerning nutritional and somatic conditions, while there is no specific, approved medication, it seems essential not to neglect the interest of innovative therapeutic strategies to treat multi-organic comorbidities. In the final section we discuss how to use these medications in the overall approach to the treatment of anorexia nervosa.

Heterogeneous weight restoration trajectories during partial hospitalization treatment for anorexia nervosa

Early response to treatment has been shown to predict good outcome in family-based treatment, but little is known about who responds quickly.

OBJECTIVE

The purpose of the current study was to examine the short-term weight gain trajectories among youth receiving partial hospitalization program services for anorexia nervosa (AN), and to identify predictors of these trajectories.

METHOD

Adolescent and young adults (n = 102) with AN or subthreshold AN completed semi-structured interviews and self-report measures on admission to a family-based partial hospitalization program. Patients participated in programming 5 days a week.

RESULTS

Three weight gain trajectories were found to indicate slow, moderate, and rapid weight gain trajectories. All rapid responders gained at least four lbs. in the first 4 weeks of treatment, compared to 86.1% of moderate responders and 51.2% of slow responders. Patients were less likely to have a moderate or rapid response trajectory if they had a mood disorder diagnosis and higher parental expressed emotion. Additionally, the presence of compensatory behavior increased the likelihood of having a rapid response.

DISCUSSION

Despite the sometimes chronic nature of AN, most patients fell into one of the two favorable response trajectories. The identification of these trajectories underscores the importance of considering the core disordered eating behaviors (i.e., restricting, binge eating, and purging), comorbid psychopathology, and parental expressed emotion.

Relationship between desired weight constructs and eating disorder severity following treatment for anorexia nervosa

BACKGROUND

Desired weight is an indicator of illness severity in youth with anorexia nervosa (AN), but its impact on eating disorder symptoms over time and in adults is unknown. This study examined longitudinal associations between two desired weight constructs (desired weight percentage, weight difference percentage) and eating disorder severity and body mass index (BMI) in patients aged 16-62 years old with AN presenting for inpatient or day hospital treatment.

METHOD

Participants (N = 160) completed the Eating Disorder Examination and measures of height and weight at treatment admission, discharge, and 3, 6, and 12 months post-discharge. Desired weight percentage was calculated as [desired BMI(desired weight in kg/height in meters² )/healthy BMI] × 100. weight difference percentage was calculated as [(actual weight-desired weight)/actual weight] × 100.

RESULTS

At admission, participants were approximately 78.6% of a healthy BMI and desired to be 81% of a healthy BMI. During the year following treatment, participants were 89% of a healthy BMI, but wanted to be 86% of a healthy BMI. Individuals with lower desired weight percentage (wanting to be a lower percentage of a healthy BMI) or higher weight difference percentage (wanting to lose a larger percentage of weight) at treatment admission endorsed greater eating disorder severity across time. Additionally, individuals with higher desired weight percentage or weight difference percentage had higher BMIs at intake, and greater increases in BMI over time.

DISCUSSION

Results highlight that desired weight constructs represent correlates of illness severity in AN and may inform an individual's likely weight trajectory during and after treatment.

A new approach to eating-disorder classification: Using empirical methods to delineate diagnostic dimensions and inform care

OBJECTIVE

Despite changes to the diagnostic criteria for eating disorders (EDs) in the DSM-5, the current diagnostic system for EDs has limited ability to inform treatment planning and predict outcomes. Our objective was to test the clinical utility of a novel dimensional approach to understanding the structure of ED psychopathology.

METHOD

Participants (N = 243; 82.2% women) were community-recruited adults with a DSM-5 ED assessed at baseline, 6-month, and 1-year follow-up. Hierarchical factor analysis was used to identify a joint hierarchical-dimensional structure of eating, mood, and anxiety symptoms. Exploratory structural equation modeling was used to test the ability of the dimensional model to predict outcomes.

RESULTS

At the top of the hierarchy, we identified a broad Internalizing factor that reflected diffuse symptoms of eating, mood, and anxiety disorders. Internalizing branched into three subfactors: distress, fear-avoidance (fears of certain stimuli and behaviors to neutralize fears, including ED behaviors designed to reduce fear of weight gain), and body dissatisfaction, which was nested within distress. The lowest level of the hierarchy was characterized by 15 factors. The hierarchical model predicted 60.1% of the variance in outcomes at 6-month follow-up, whereas all DSM eating, mood, and anxiety disorders combined predicted 35.8% of the variance in outcomes.

DISCUSSION

A dimensional approach to understanding and diagnosing EDs improved the ability to prospectively predict clinical course above-and-beyond the traditional categorical (DSM-based) approach. Our findings have implications for endeavors to improve the prediction of ED prognosis and course, and to develop more effective trans-diagnostic treatments.

Less symptomatic, but equally impaired: Clinical impairment in restricting versus binge-eating/purging subtype of anorexia nervosa

OBJECTIVE

This study investigated subtype differences in eating disorder-specific impairment in a treatment-seeking sample of individuals with anorexia nervosa (AN).

METHOD

The Clinical Impairment Assessment (CIA) and the Eating Disorder Examination-Questionnaire (EDE-Q) were administered to 142 patients. Of these, 54.9% were classified as restricting type (AN-R) and 45.1% were classified as binge-eating/purging type (AN-B/P) based on an average weekly occurrence of binge eating and/or purging episodes (≥4 episodes/28days).

RESULTS

Individuals with AN-B/P exhibited higher levels of core ED psychopathology (dietary restraint, eating concern, shape/weight concerns) in addition to the expected higher frequency of binge/purge episodes. No significant differences existed between AN subtypes in the severity of ED-related impairment. Weight/shape concerns and binge eating frequency significantly predicted level of impairment. Differential associations were observed between the type of ED pathology that significantly contributed to impairment according to AN subtype.

DISCUSSION

Although those with AN-B/P displayed higher levels of core attitudinal and behavioral ED pathology than AN-R, no significant differences in ED-specific impairment were found between AN subtypes. Eating disorder-related impairment in AN was not related to the severity of underweight or purging behaviors, but was uniquely and positively associated with weight/shape concerns and binge eating frequency.

Are eating disorders "all about control?" The elusive psychopathology of nonfat phobic presentations

OBJECTIVE

There are a subset of individuals with eating disorders (EDs) who do not overevaluate body shape/weight (i.e., nonfat phobic ED; NFP-ED). According to the transdiagnostic cognitive-behavioral conceptualization of EDs, a need for control, in general, is hypothesized as the core psychopathology of NFP-EDs, with shape- and weight-related motivations for ED behavior merely superimposed in FP-ED presentations. This study tested the need for control as motivation for restriction in NFP-ED, using items aimed at assessing control from the Eating Disorder Examination (EDE) Restraint scale.

METHOD

Females ages 13-27 years consecutively admitted to residential treatment completed the EDE, Eating Disorder Inventory-3 Drive for Thinness subscale (EDI-DFT), and other self-report measures of psychopathology. We included patients with DSM-5 EDs, but excluded patients with avoidant/restrictive food intake disorder. Twenty participants had NFP-ED (≤14 on EDI-DFT) and 124 had fatphobic ED (FP-ED; >14 on EDI-DFT).

RESULTS

NFP-ED scored significantly lower than FP-ED on EDE Restraint scale shape/weight [χ² (1) = 10.73-35.62, p's < .01] and on control items [χ² (1) = 10.72-20.62, p's < .01], in addition to scoring lower on measures of general psychopathology and impairment.

DISCUSSION

Findings suggest those with NFP-ED report lower psychopathology overall and the new EDE Restraint scale control items do not capture additional motivation for restriction beyond that captured in the original Restraint scale shape/weight items. Future research should examine whether this latter finding is due to a minimizing response style in NFP-ED, an incomplete capture of desire for control by the EDE assessment method, or indeed reflects that need for control does not motivate restriction in NFP-EDs.

Application of structural equation mixture modeling to characterize the latent structure of eating pathology

OBJECTIVE

Several theoretical models describe the structure of eating disorders (EDs), and a burgeoning empirical literature has sought to identify whether eating pathology is conceptualized best as categorical (presence or absence of disorder), dimensional (continuous), or a hybrid of categories and dimensions.

METHODS

This study used structural equation mixture modeling (SEMM) to identify the latent structure of EDs. Items from the Eating Pathology Symptoms Inventory (EPSI) were administered to individuals with EDs (N = 344). Select EPSI scales and body mass index were indicators in subsequent SEMM analyses. The Inventory of Depression and Anxiety Symptoms (IDAS), ED diagnoses, and select demographic variables were used as validators using chi-square or MANOVA.

RESULTS

Categorical models fit the data better than latent dimensional or hybrid models. Latent profile 1 (LP1) was non-fat-phobic restricting anorexia nervosa; LP2, an obese, binge-eating class; LP3, non-purging bulimia nervosa; LP4, fat-phobic restricting anorexia nervosa; and LP5, multiple purging bulimia nervosa. External validation analyses indicated that LP4 and LP5 had the highest non-ED-related psychopathology.

DISCUSSION

These findings indicate that there is substantial variability in the phenomenology of traditional DSM-based ED categories across latent profiles, and highlight the salience of certain ED phenotypes that have been debated in the literature. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:542-550).

Characterizing severe and enduring anorexia nervosa: An empirical approach

Targeted approaches for the treatment of severe and enduring anorexia nervosa (SE-AN) have been recommended, but there is no consensus definition of SE-AN to inform research and clinical practice. This study aimed to take initial steps toward developing an empirically based definition of SE-AN by characterizing associations among putative indicators of severity and chronicity in eating disorders. Patients with AN (N = 355) completed interviews and questionnaires at treatment admission and discharge; height and weight were assessed to calculate body mass index (BMI). Structural equation mixture modeling was used to test whether associations among potential indicators of SE-AN (illness duration, treatment history, BMI, binge eating, purging, quality-of-life) formed distinct subgroups, a single group with one or more dimensions, or a combination of subgroups and dimensions. A three-factor (dimensional), two-profile (categorical) mixture model provided the best fit to the data. Factor 1 included eating disorder behaviors; Factor 2 comprised quality-of-life domains; Factor 3 was characterized by illness duration, number of hospitalizations, and admission BMI. Profiles differed on eating disorder behaviors and quality-of-life, but not on indicators of chronicity or BMI. Factor scores, but not profile membership, predicted outcome at discharge from treatment. Data suggest that patients with AN can be classified on the basis of eating disorder behaviors and quality-of-life, but there was no evidence for a chronic subgroup of AN. Rather, indices of chronicity varied dimensionally within each class. Given that current definitions of SE-AN rely on illness duration, these findings have implications for research and clinical practice.

Application of network analysis to identify interactive systems of eating disorder psychopathology

BACKGROUND

Traditional approaches for the classification of eating disorders (EDs) attribute symptoms to an underlying, latent disease entity. The network approach is an alternative model in which mental disorders are represented as networks of interacting, self-reinforcing symptoms. This project was the first to use network analysis to identify interconnected systems of ED symptoms.

METHOD

Adult participants (n = 143; 77.6% women) with a Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) ED were recruited from the community to take part in a larger ongoing longitudinal study. The Structured Clinical Interview for DSM Disorders (SCID-I) was used to establish diagnoses. An undirected network of ED symptoms was created using items from the Eating Pathology Symptoms Inventory (EPSI) and the R package qgraph.

RESULTS

Body checking emerged as the strongest and most important single symptom in the entire network by having the shortest average distance to other symptoms in the network, and by being the most frequent symptom on the path between any two other symptoms. Feeling the need to exercise every day and two symptoms assessing dietary restraint/restricting emerged as 'key players', such that their removal from the network resulted in maximal fracturing of the network into smaller components.

CONCLUSIONS

Although cognitive-behavioral therapy for EDs focuses on reducing body checking to promote recovery, our data indicate that amplified efforts to address body checking may produce stronger (and more enduring) effects. Finally, results of the 'key players analysis' suggested that targeting interventions at these key nodes might prevent or slow the cascade of symptoms through the 'network' of ED psychopathology.

The importance of loss of control while eating in adolescents with purging disorder

OBJECTIVE

Although many individuals with purging disorder (PD) report loss of control (LOC) eating, it is unclear whether they differ from those who do not, or from other eating disorders involving purging and/or LOC.

METHOD

We compared PD with LOC (PD-LOC), PD without LOC (PD-noLOC), bulimia nervosa (BN), and anorexia nervosa-binge/purge subtype (AN-B/P) on measures of eating-related and general psychopathology in treatment-seeking adolescents.

RESULTS

PD-LOC comprised ∼30% of PD diagnoses. PD-LOC and PD-noLOC did not differ from one another, or from BN and AN-B/P, on most measures of psychopathology, with some exceptions. PD-noLOC was similar to AN-B/P (p = 0.99) and significantly different from BN on eating concerns (p < 0.001), while PD-LOC was similar to BN, AN-B/P, and PD-noLOC on this measure (ps ≥ 0.06). PD-LOC reported higher self-esteem than BN, AN-B/P, and PD-noLOC (ps < 0.001).

DISCUSSION

PD was largely similar to other eating disorders characterized by purging, regardless of whether LOC eating was present. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:801-804).

Examining weight suppression as a predictor of eating disorder symptom trajectories in anorexia nervosa

OBJECTIVE

Research in individuals with bulimia nervosa has highlighted the clinical significance of weight suppression (WS), defined as the difference between one's highest and current weight. More recently, studies have suggested that WS also may play a role in symptom maintenance and weight gain during treatment in anorexia nervosa (AN) and that the influence of WS on AN outcomes may depend on an individual's body mass index (BMI). However, no study has investigated whether WS or the interaction between WS and BMI is associated with the longer-term course of eating pathology following treatment discharge in patients with AN.

METHOD

The current study examined a sample of females with AN (N = 180) who completed interviews and self-report questionnaires at discharge from intensive treatment and at 3, 6, and 12-months after discharge. Latent growth curve models tested whether WS, BMI, or the WS by BMI interaction significantly predicted the trajectory of eating disorder symptoms (i.e., Eating Disorder Examination global score, BMI, frequency of loss of control eating, frequency of purging) over the year following discharge.

RESULTS

WS at discharge predicted change in BMI, and the interaction between WS and BMI predicted growth in eating disorder severity and purging frequency over time. Neither WS nor its interaction with BMI predicted growth in loss of control eating frequency.

DISCUSSION

Results provide further support for the clinical significance of WS in AN symptom maintenance, but suggest that the influence of WS likely depends on an individual's BMI as well as the outcome being measured. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:753-763).

Targeting Neural Endophenotypes of Eating Disorders with Non-invasive Brain Stimulation

The term "eating disorders" (ED) encompasses a wide variety of disordered eating and compensatory behaviors, and so the term is associated with considerable clinical and phenotypic heterogeneity. This heterogeneity makes optimizing treatment techniques difficult. One class of treatments is non-invasive brain stimulation (NIBS). NIBS, including repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), are accessible forms of neuromodulation that alter the cortical excitability of a target brain region. It is crucial for NIBS to be successful that the target is well selected for the patient population in question. Targets may best be selected by stepping back from conventional DSM-5 diagnostic criteria to identify neural substrates of more basic phenotypes, including behavior related to rewards and punishment, cognitive control, and social processes. These phenotypic dimensions have been recently laid out by the Research Domain Criteria (RDoC) initiative. Consequently, this review is intended to identify potential dimensions as outlined by the RDoC and the underlying behavioral and neurobiological targets associated with ED. This review will also identify candidate targets for NIBS based on these dimensions and review the available literature on rTMS and tDCS in ED. This review systematically reviews abnormal neural circuitry in ED within the RDoC framework, and also systematically reviews the available literature investigating NIBS as a treatment for ED.

Dynamic longitudinal relations between emotion regulation difficulties and anorexia nervosa symptoms over the year following intensive treatment

OBJECTIVE

Emotion regulation difficulties have been implicated in theoretical models of anorexia nervosa (AN) development/maintenance, and several treatments for AN have been designed to target emotion dysregulation. However, no research has used longitudinal methodology to examine whether emotion regulation difficulties predict the maintenance of AN symptoms, or vice versa. The current study evaluated dynamic longitudinal relations between emotion dysregulation and AN symptom severity over the year following discharge from intensive treatment in order to enhance theoretical models and treatments for AN.

METHOD

Participants were 191 patients with AN recruited during intensive treatment. Assessments including the Eating Disorders Examination and the Difficulties in Emotion Regulation Scale were completed at discharge from treatment and at 3-, 6-, and 12-month follow-ups. Bivariate latent change score models were used to examine the direction of associations between emotion dysregulation and AN symptom severity across time.

RESULTS

Emotion dysregulation predicted change in AN symptom severity, but the reverse relationship did not occur. Individuals with high levels of emotion dysregulation experienced an increase and subsequent maintenance of AN psychopathology, whereas low emotion dysregulation predicted a decreasing AN symptom trajectory. Importantly, these dynamic temporal relationships could not be accounted for by body mass index or depressive symptoms and were present for patients with the restricting and binge-eating/purging subtypes of AN.

CONCLUSIONS

Emotion regulation difficulties appear to be involved in the maintenance of AN symptom severity over time. Findings provide support for an increasing emphasis on emotion regulation in the development of novel treatments for AN.

Recent Advances in Developmental and Risk Factor Research on Eating Disorders

The Diagnostic and Statistical Manual of Mental Disorders (i.e., DSM-5) currently recognizes three primary eating disorders: anorexia nervosa, bulimia nervosa, and binge eating disorder. The origins of eating disorders are complex and remain poorly understood. However, emerging research highlights a dimensional approach to understanding the multifactorial etiology of eating disorders as a means to inform assessment, prevention, and treatment efforts. Guided by research published since 2011, this review summarizes recent findings elucidating risk factors for the development of eating disorders across the lifespan in three primary domains: (1) genetic/biological, (2) psychological, and (3) socio-environmental. Prospective empirical research in clinical samples with full-syndrome eating disorders is emphasized with added support from cross-sectional studies, where relevant. The developmental stages of puberty and the transition from adolescence to young adulthood are discussed as crucial periods for the identification and prevention of eating disorders. The importance of continuing to elucidate the mechanisms underlying gene by environmental interactions in eating disorder risk is also discussed. Finally, controversial topics in the field of eating disorder research and the clinical implications of this research are summarized.

Do recognizable lifetime eating disorder phenotypes naturally occur in a culturally asian population? A combined latent profile and taxometric approach

BACKGROUND

We examined whether empirically derived eating disorder (ED) categories in Hong Kong Chinese patients (N = 454) would be consistent with recognizable lifetime ED phenotypes derived from latent structure models of European and American samples.

METHOD

We performed latent profile analysis (LPA) using indicator variables from data collected during routine assessment, and then applied taxometric analysis to determine whether latent classes were qualitatively versus quantitatively distinct.

RESULTS

Latent profile analysis identified four classes: (i) binge/purge (47%); (ii) non-fat-phobic low-weight (34%); (iii) fat-phobic low-weight (12%); and (iv) overweight disordered eating (6%). Taxometric analysis identified qualitative (categorical) distinctions between the binge/purge and non-fat-phobic low-weight classes, and also between the fat-phobic and non-fat-phobic low-weight classes. Distinctions between the fat-phobic low-weight and binge/purge classes were indeterminate.

CONCLUSION

Empirically derived categories in Hong Kong showed recognizable correspondence with recognizable lifetime ED phenotypes. Although taxometric findings support two distinct classes of low weight EDs, LPA findings also support heterogeneity among non-fat-phobic individuals.

Emotion dysregulation and anorexia nervosa: an exploration of the role of childhood abuse

OBJECTIVE

Theoretical models of emotion regulation difficulties in anorexia nervosa (AN) specify a role for factors that predispose to or precipitate emotion dysregulation. The current study considered whether childhood abuse (i.e., emotional, sexual, physical) might be related to emotion regulation difficulties and eating disorder symptom severity in patients with AN. Childhood abuse was hypothesized to relate to AN symptoms indirectly via emotion dysregulation.

METHOD

Participants were 188 patients with AN presenting to an intensive treatment facility. The Childhood Trauma Questionnaire, Difficulties in Emotion Regulation Scale, and Eating Disorder Examination were used to assess childhood abuse, emotion dysregulation, and AN symptom severity, respectively.

RESULTS

Of the three forms of childhood abuse, reports of emotional abuse were most strongly related to emotion regulation difficulties and AN symptom severity. Mediation analyses revealed that emotion dysregulation significantly explained the relationship between childhood emotional abuse and AN symptomatology, and mediation effects did not differ by AN subtype (i.e., restricting vs. binge-eating/purging).

DISCUSSION

Findings provide initial support for a model in which childhood emotional abuse precipitates emotion dysregulation and the development of AN. Future studies with longitudinal designs and control groups are necessary to examine the direction and specificity of these cross-sectional associations

Bidirectional associations between binge eating and restriction in anorexia nervosa. An ecological momentary assessment study

This study examined the association between restrictive eating behaviors and binge eating in anorexia nervosa (AN) using data collected in the natural environment. Women (N = 118) with DSM-IV full or subthreshold AN reported eating disorder behaviors, including binge eating episodes, going ≥ 8 waking hours without eating, and skipping meals, during 2 weeks of ecological momentary assessment (EMA). Time-lagged generalized estimating equations tested the following hypotheses: 1) dietary restriction would predict binge eating while controlling for binge eating the previous day; 2) binge eating would predict restriction the subsequent day while controlling for restriction the previous day. After controlling for relevant covariates, the hypotheses were not supported; however, there appeared to be a cumulative effect of repeatedly going 8 consecutive hours without eating (i.e. fasting) on the risk of binge eating among individuals who recently engaged in binge eating. In addition, skipping meals was associated with a lower risk of same day binge eating. The relationship between binge eating and dietary restriction appears to be complex and may vary by type of restrictive eating behavior. Future research should aim to further clarify the nature of the interaction of binge eating and restrictive eating among individuals with AN in order to effectively eliminate these behaviors in treatment.