Categorical versus dimensional models of eating disorders: an examination of the evidence

The value of a multidisciplinary consensus meeting in achieving agreement on eating disorders diagnosis at a specialized referral center

OBJECTIVE

This study aimed to evaluate the concordance of eating disorders (EDs) diagnoses within a multidisciplinary team in a specialized hospital unit dedicated to the medical care of ED.

METHODS

The study analyzed data from 608 female patients who sought consultation at the Eating Disorders Referral Center between 2017 and 2021. The diagnoses were established according to the DSM-5 criteria by endocrinologists, psychiatrists, and finally confirmed or discussed within a monthly multidisciplinary consensus meeting (MCM). Fleiss' Kappa tests were conducted to assess inter-raters' agreement.

RESULTS

Overall, substantial agreement was observed between endocrinologists and psychiatrists and the MCM. A more detailed analysis revealed variations in agreement across different disorders. Certain EDs demonstrated substantial agreement (e.g., anorexia nervosa restrictive subtype), while others approached near-perfect agreement (e.g., binge-eating disorder). In contrast, agreement was fair to poor for anorexia nervosa binge-purge subtype (ANBP) and slight for other specified feeding and ED. A period of temporary disagreement was noted for ANBP, partially attributed to practitioner turnover. An improvement in interdisciplinary agreement was observed for all ED diagnoses by the end of the study period.

DISCUSSION

Variations or lower levels of inter-rater agreement may stem from atypical cases that fall on the border between two diagnoses or complex cases, as well as fluctuating symptoms. The progress observed throughout the study can be attributed in part to interdisciplinary learning, particularly facilitated by the MCM. The findings underscore the significance of striving for optimal concordance among different medical specialties to enhance patient care in ED treatment.

PUBLIC SIGNIFICANCE

This study scrutinizes the agreement levels of ED diagnoses among endocrinologists and psychiatrists within a multidisciplinary team at an Eating Disorders Referral Center. While substantial overall agreement was achieved, disparities or lower agreement levels were evident for certain diagnoses such as anorexia nervosa binge-purge subtype. However, collaborative meetings led to a progressive enhancement in agreement over time. This research underscores the crucial role of a multidisciplinary team working collectively to ensure precise diagnoses and improved care for patients with EDs.

From symptoms to subjective and bodily experiences: the contribution of the Psychodynamic Diagnostic Manual (PDM-2) to diagnosis and treatment monitoring in eating disorders

PURPOSE

Atheoretical and descriptive conceptualizations of eating disorders (EDs) have faced substantial criticism due to their limited ability to assess patients' subjective characteristics and experiences, as needed to determine the most appropriate treatment options. The present article provides an overview of the clinical and empirical literature supporting the potential contribution of the Psychodynamic Diagnostic Manual (PDM-2) to both diagnostic assessment and treatment monitoring.

METHODS

Following a discussion of the most relevant shortcomings of current diagnostic models of EDs and a description of the rationale and structure of the PDM-2, evidence supporting the core PDM-2 dimensions of ED patients' subjective experiences (i.e., affective states, cognitive processes, relational patterns, somatic/bodily experiences and states) are examined, alongside their relevance to ED diagnosis and treatment.

RESULTS

Overall, the reviewed studies support the diagnostic importance of these patterns of subjective experiences in EDs, highlighting their potential role as either predisposing or maintaining factors to target in psychotherapy. A growing body of multidisciplinary evidence also shows that bodily and somatic experiences are central to the diagnosis and clinical management of ED patients. Moreover, there is evidence that a PDM-based assessment may enable closer monitoring of patient progress during treatment, with regard to both subjective experiences and symptom patterns.

CONCLUSIONS

The study suggests that current diagnostic frameworks for EDs would benefit from the addition of a person-centered perspective that considers not only symptoms, but also patients' full range of functioning-including their deep and surface-level emotional, cognitive, interpersonal, and social patterns-to improve patient-tailored interventions.

LEVEL OF EVIDENCE

Level V, narrative review.

An integrative evolutionary framework for psychopathology

The field of psychopathology is in a transformative phase, and is witnessing a renewed surge of interest in theoretical models of mental disorders. While many interesting proposals are competing for attention in the literature, they tend to focus narrowly on the proximate level of analysis and lack a broader understanding of biological function. In this paper, we present an integrative framework for mental disorders built on concepts from life history theory, and describe a taxonomy of mental disorders based on its principles, the fast-slow-defense model (FSD). The FSD integrates psychopathology with normative individual differences in personality and behavior, and allows researchers to draw principled distinctions between broad clusters of disorders, as well as identify functional subtypes within current diagnostic categories. Simulation work demonstrates that the model can explain the large-scale structure of comorbidity, including the apparent emergence of a general "p factor" of psychopathology. A life history approach also provides novel integrative insights into the role of environmental risk/protective factors and the developmental trajectories of various disorders.

Bridging cognitive, phenomenological and psychodynamic approaches to eating disorders

Cognitive, psychodynamic, and phenomenological scholars converged their attention on abnormal bodily phenomena as the core psychopathological feature of eating disorders (EDs). While cognitive approaches focus their attention on a need for "objective" (i.e., observable, measurable) variables (including behaviours and distorted cognitions), the phenomenological exploration typically targets descriptions of persons' lived experience. According to a new emerging phenomenological perspective, the classic behavioural and cognitive symptoms of EDs should be considered as epiphenomena of a deeper core represented by a disorder of the embodiment. The cognitive-behavioural model is the most studied and, up till now, clinically efficacious treatment for EDs. However, as any coherent and scientifically grounded model, it presents some limitations in its application. Numerous patients report a chronic course, do not respond to treatment and develop a personality structure based on pathological eating behaviours, since "being anorexic" becomes a new identity for the person. Furthermore, the etiopathogenetic trajectory of EDs influences the treatment response: for example, patients reporting childhood abuse or maltreatment respond differently to cognitive-behavioural therapy. To obtain a deeper comprehension of these disorders, it seems important to shift attention from abnormal eating behaviours to more complex and subtle psycho(patho)logical features, especially experiential ones. This characterisation represents the unavoidable premise for the identification of new therapeutic targets and consequently for an improvement of the outcome of these severe disorders. Thus, the present review aims to provide an integrated view of cognitive, psychodynamic, and phenomenological perspectives on EDs, suggesting new therapeutic targets and intervention strategies based on this integrated model. Level of Evidence: Level V.Level of evidence Level V: Opinions of authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.

The Complicated Relationship between Dieting, Dietary Restraint, Caloric Restriction, and Eating Disorders: Is a Shift in Public Health Messaging Warranted?

The origins of theories specifying dietary restraint as a cause of eating disorders can be traced to the 1970s. This paper will present an overview of the origins of dietary restraint theories and a brief historical review of evidence will be summarized. Recent research will be presented, including the results from the CALERIE Phase 1 study, as well as CALERIE Phase 2, which were NIH-sponsored randomized controlled trials. CALERIE 2 provided a test of the effect of two years of caloric restriction (CR) on the development of eating disorder syndromes and symptoms in comparison to a control group that did not alter eating behavior or body weight. The intervention was effective for inducing a chronic (two-year) reduction in total energy expenditure and increased dietary restraint but did not increase symptoms of eating disorders. The results of this recent investigation and other studies have not provided experimental support for conventional dietary restraint theories of eating disorders. These findings are discussed in terms of potential revisions of dietary restraint theory, as well as the implications for a paradigm shift in public health messaging related to dieting.

Overcoming limitations of self-report: an assessment of fear of weight gain in anorexia nervosa and healthy controls using implicit association tests

BACKGROUND

Fear of weight gain is a characteristic feature of anorexia nervosa (AN), and reducing this fear is often a main target of treatment. However, research shows that 20% of individuals with AN do not report fear of weight gain. Studies are needed that evaluate the centrality of fear of weight gain for AN with a method less susceptible to deception than self-report.

METHODS

We approximated implicit fear of weight gain by measuring implicit drive for thinness using implicit association tests (IATs). We asked 64 participants (35 AN, 29 healthy controls [HCs]) to categorize statements as pro-dieting vs. non-dieting and true vs. false in a questionnaire-based IAT, and pictures of underweight vs. normal-weight models and positive vs. negative words in a picture-based IAT using two response keys. We tested for associations between implicit drive for thinness and explicitly reported psychopathology within AN as well as group differences between AN and HC groups.

RESULTS

Correlation analyses within the AN group showed that higher implicit drive for thinness was associated with more pronounced eating disorder-specific psychopathology. Furthermore, the AN group showed a stronger implicit drive for thinness than HCs in both IATs.

CONCLUSION

The results highlight the relevance of considering fear of weight gain as a continuous construct. Our implicit assessment captures various degrees of fear of weight gain in AN, which might allow for more individually tailored interventions in the future.

Childhood trauma and disordered eating: Exploring the role of alexithymia and beliefs about emotions

Although often perceived as non-threatening, disordered eating poses a significant risk to physical and psychological wellbeing. Given the modest effectiveness of current interventions, there is a need to identify specific psychological targets for treatment. One risk factor that has long been liked to eating issues is childhood trauma. The present study aimed to clarify the associations between five distinct forms of trauma and three disordered eating behaviours (Cognitive Restraint, Uncontrolled Eating, and Emotional Eating). In addition, it aimed to determine the role of alexithymia and beliefs about emotions in this association. Three hundred and thirty-two participants from the Australian community completed an online questionnaire measuring alexithymia, beliefs about emotions, disordered eating, and childhood trauma. Hierarchical multiple regression analyses were conducted to examine total effects between independent forms of childhood trauma and eating behaviours, followed by bootstrapped confidence intervals to delineate indirect effects. A significant direct association was evidenced between Childhood Emotional Abuse and Cognitive Restraint, in addition to Childhood Sexual Abuse and Emotional Eating. Numerous indirect effects were detected involving the beliefs that emotions are 'Overwhelming and Uncontrollable' and 'Damaging'. Findings indicated that experiences of childhood trauma were associated with disordered eating behaviours through the detection of significant total and/or indirect effects. However, effect sizes of indirect effects (involving beliefs about emotions) were small, suggesting that there are additional factors involved. Further longitudinal research is necessary to determine the causal direction of these findings.

The comorbidity of eating disorders in bipolar disorder and associated clinical correlates characterised by emotion dysregulation and impulsivity: A systematic review

BACKGROUND

Individuals with bipolar disorder (BD) have an increased risk of developing eating disorders (ED) or disordered eating symptoms compared to the general population. Eating pathology characterised by binge and/or purge symptomatology are the most common to develop in BD, yet the underlying aetiological mechanisms are relatively unknown. Theoretical models of BD-ED comorbidity suggest that shared pathophysiological factors, including emotion dysregulation and impulsivity may contribute to the development of binge/purge eating pathology in BD.

METHOD

A systematic search was conducted to assess two research questions: 1. What are the prevalence or incidence rates of different ED in BD? 2. Are clinical correlates hallmarked by emotion dysregulation and/or impulsivity (alcohol/substance use disorders, mood instability and suicidality) significantly elevated in BD with ED (BD-ED) groups compared to BD only?

RESULTS

Any type of lifetime or current ED ranged from 1.9% to 33.3% in BD. Type of BD diagnosis did not appear to significantly impact likelihood of ED development. Alcohol use disorder, mood instability and suicidality were significantly higher in BD-ED compared to BD only.

LIMITATIONS

Potential biases within the selected studies; impacting generalisability of results and comparability between studies. Varying treatment interventions (including medications) may confound results and comparability between studies. Assessment of binge eating varied, also limiting comparability.

CONCLUSION

Eating pathology may occur comorbidly with BD due to shared underlying pathophysiological features. This could have significant implications for future interventions; both psychopharmacological and psychotherapeutic. More comprehensive investigations are required to identify the functionality of dysregulated emotion and impulsivity in the development of eating pathology in BD.

Identifying Risk Factors for Disordered Eating among Female Youth in Primary Care

Eating disorders are a serious, life-threating condition impacting adolescents and young adults. Providers in primary care settings have an important role in identifying disordered eating (DE) symptoms. Unfortunately, symptoms go undetected in 50% of patients in medical settings. Using the behavioral health screen, this study identified DE risk profiles in a sample of 3620 female adolescents and young adults (ages 14-24), presenting in primary care. A latent class analysis with twenty psychosocial factors identified three DE risk groups. The group at highest risk for DE was characterized by endorsement of internalizing symptoms and a history of trauma. The next risk group consisted of those with externalizing symptoms, particularly substance use. The group at lowest risk for DE reported more time spent with friends compared to their peers. Primary care providers and psychiatric teams can benefit from knowing the psychosocial risk patterns affiliated with DE, and using brief, comprehensive screening tools to identify these symptoms.

Toward Quantifying the Psychopathology of Eating Disorders From the Autonomic Nervous System Perspective: A Methodological Approach

The phenomenology of Eating Disorders (ED) relates with altered functioning of the Autonomic Nervous System (ANS). The lack of agreement in what comes to the direction and significance of such alterations is possibly due to the variability in the ED spectrum. As the stress response system is an integral part of the ANS, we propose to investigate ANS tonic variations and phasic activations in response to stressors. We hypothesize that, while using stress as a test probe, characteristic ANS dysregulations in ED may be found when considering several physiological signals measured over time, and weighted by the individual psychological profiles. In this article we describe a novel methodological approach to investigate this hypothesis with the aim of providing further clarification on the ED spectrum conceptualization. The proposed methodology has been designed to be easily integrated in clinical practice and, eventually, in daily life. The population under observation includes both patients in treatment for ED, and matched controls. The study session has the duration of 1 day, including: (1) the administration of a stress task in a controlled environment and (2) naturalistic data collection. The stress task is designed to elicit both mentally and physically driven ANS activation. The naturalistic component intends to illustrate the psychophysiology in everyday life. We use wearable devices to continuously and non-invasively measure bio-signals related to ANS functioning. This information is complemented with psychometric information from validated stress and ED scales and ecological momentary assessments. The protocol has received ethical approval and has been implemented in practice, currently accounting for 37 patients (out of 120) and 16 controls (out of 60). Ongoing work focus on the definition and implementation of a data processing pipeline to quantitatively test our hypothesis, both standard statistical methods and more exploratory machine learning approaches will be considered.

The classification of eating disorders in China: A categorical model or a dimensional model

OBJECTIVE

According to the ICD-10 and DSM-5, eating disorders (EDs) are classified using a categorical model that assumes the subtypes are qualitatively different from one another. However, it is still intensely debated that a dimensional model is more suitable. The aim of this study is to examine whether EDs have a categorical or dimensional latent structure using a sample of Chinese ED patients.

METHOD

The sample included 322 patients, diagnosed with an ED from 2010 to 2017 in the Shanghai Mental Health Center, and comparison participants (N = 850), recruited from undergraduate students in one university in Shanghai. Participants were evaluated with the Eating Disorder Inventory-2 (EDI-2) questionnaire and another questionnaire developed by the researchers. Three taxometric procedures (MAXimum EIGenvalue [MAXEIG], latent-mode factor analysis [L-Mode], and Mean Above Minus Below A Cut [MAMBAC]) were applied, respectively, to analyze the patients' clinical symptoms data.

RESULTS

Patients were divided into three groups according to their clinical diagnosis. The plots of the three taxometric analysis procedures supported the categorical construct in anorexia nervosa, binge-eating/purging group, and bulimia nervosa group. The Comparison Curve Fit Indices of the MAXEIG, L-Mode, and MAMBAC procedures were 0.694, 0.709, 0.704 in the AN-BP group and 0.727, 0.67, 0.62 in the BN group, respectively, which also support the categorical construct.

DISCUSSION

The results support two distinct classes of ED subtypes among Chinese sample. Further work on applying hybrid model in analysis has been discussed.

A review of purging disorder through meta-analysis

Although a growing body of research has examined Purging Disorder (PD), there remains a lack of conclusive evidence regarding the diagnostic validity of PD. This meta-analysis compared PD to DSM-5 eating disorders (i.e., Anorexia Nervosa [AN], Bulimia Nervosa [BN], and Binge Eating Disorder [BED]) and controls. A comprehensive literature search identified 38 eligible studies. Group differences on indicators of course of illness and both general and eating psychopathology were assessed using standardized effect sizes. Results supported the conceptualization of PD as a clinically significant eating disorder, but findings were less clear regarding its distinctiveness from other eating disorder diagnoses. More specifically, PD significantly differed from BN and BED in natural course of illness (g = .40-.54), and PD significantly differed from AN in treatment outcome (g = .27), with PD characterized by a better prognosis. Overall, PD was more similar to AN and BED on many dimensional measures of general and eating-related psychopathology, though PD was less severe than BN in most of these domains. PD, BN, and BED groups also evidenced similar frequencies of subjective binge episodes (SBEs), yet PD evidenced less frequent SBEs than AN. There is a clear need for future studies of PD to assess validators that have not been reported comprehensively in the literature, such as mortality, medical morbidity, and course of illness. Additionally, empirical classification studies are needed to inform future classifications of PD, particularly with regard to categorical differences between PD and other eating disorders. (PsycINFO Database Record

Male clinical norms and sex differences on the Eating Disorder Inventory (EDI) and Eating Disorder Examination Questionnaire (EDE-Q)

OBJECTIVE

Evidence indicates that males account for a significant minority of patients with eating disorders (EDs). However, prior research has been limited by inclusion of small and predominantly non-clinical samples of males. This study aimed to (1) provide male clinical norms for widely used ED measures (Eating Disorder Examination Questionnaire [EDE-Q] and Eating Disorder Inventory-3 [EDI-3]) and (2) examine sex differences in overall ED psychopathology.

METHOD

Participants were 386 male and 1,487 female patients with an ED diagnosis aged 16 years and older who completed the EDE-Q and EDI-3 upon admission to a residential or partial hospital ED treatment program.

RESULTS

Normative data were calculated for the EDE-Q (global and subscales) and the EDI-3 (drive for thinness, body dissatisfaction, and bulimia). Analyses of variance (ANOVAs) used to examine sex, ED diagnosis, and their interaction in relation to overall ED psychopathology revealed a consistent pattern of greater severity among females for ED psychopathology.

DISCUSSION

This study provides clinical norms on the EDE-Q and the EDI-3 for males with clinically diagnosed EDs. It is unclear whether the greater severity observed in females reflects qualitative differences in ED presentation or true quantitative differences in ED severity. Additional research examining the underlying nature of these differences and utilizing male-specific ED measures with clinical samples is warranted.

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).

Typical patterns of disordered eating among Swedish adolescents: associations with emotion dysregulation, depression, and self-esteem

BACKGROUND

Using the person-oriented approach, we determined the relationships between four indicators (restraint and eating, shape, and weight concerns) of disordered eating (DE), as measured by the self-reported Eating Disorders Examination Questionnaire (EDE-Q), to identify typical DE patterns. We then related these patterns to clinical EDE-Q cut-off scores and emotion dysregulation, depression, self-esteem, and two categories of DE behaviors (≥2 or ≤1 "yes" responses on the SCOFF questionnaire).

METHOD

Typical patterns of DE were identified in a community sample of 1,265 Swedish adolescents (M_age  = 16.19, SD = 1.21; age range 13.5-19 years) using a cluster analysis. Separate analyses were performed for girls (n = 689) and boys (n = 576).

RESULTS

The cluster analysis yielded a six-cluster solution for each gender. Four of the six clusters for girls and five for boys showed scores above the clinical cut-off on at least one of the four DE indicators. For girls, the two clusters that scored above the clinical cut-offs on all four DE indicators reported severe psychological problems, including high scores on emotion dysregulation and depression and low scores on self-esteem. In contrast, for boys, although two clusters reported above the clinical cut-off on all four indicators, only the cluster with exceedingly high scores on shape and weight concerns reported high emotion dysregulation and depression, and extremely low self-esteem. Furthermore, significantly more girls and boys in the most problematic DE clusters reported ≥2 "yes" responses on the SCOFF questionnaire (as opposed to ≤1 response), indicating clear signs of DE and severe psychological difficulties.

CONCLUSION

We suspect that the various problematic DE patterns will require different paths back to a healthy diet. However, more research is needed to determine the developmental trajectories of these DE patterns and ensure more precise clinical cut-off scores, especially for boys. Comprehensive understanding of DE patterns might be of use to healthcare professionals for detecting DE before it develops into an eating disorder.

TRIAL REGISTRATION

Lund, EPN (dnr: 2012/499).

n-back task performance and corresponding brain-activation patterns in women with restrictive and bulimic eating-disorder variants: preliminary findings

Eating disorder (ED) variants characterized by "binge-eating/purging" symptoms differ from "restricting-only" variants along diverse clinical dimensions, but few studies have compared people with these different eating-disorder phenotypes on measures of neurocognitive function and brain activation. We tested the performances of 19 women with "restricting-only" eating syndromes and 27 with "binge-eating/purging" variants on a modified n-back task, and used functional magnetic resonance imaging (fMRI) to examine task-induced brain activations in frontal regions of interest. When compared with "binge-eating/purging" participants, "restricting-only" participants showed superior performance. Furthermore, in an intermediate-demand condition, "binge-eating/purging" participants showed significantly less event-related activation than did "restricting-only" participants in a right posterior prefrontal region spanning Brodmann areas 6-8-a region that has been linked to planning of motor responses, working memory for sequential information, and management of uncertainty. Our findings suggest that working memory is poorer in eating-disordered individuals with binge-eating/purging behaviors than in those who solely restrict food intake, and that observed performance differences coincide with interpretable group-based activation differences in a frontal region thought to subserve planning and decision making.

The Loss of Control Over Eating Scale: development and psychometric evaluation

OBJECTIVE

This study describes the development, content validity, and convergent validity of the Loss of Control over Eating Scale (LOCES).

METHOD

An initial pool of 56 items covering 13 facets of loss-of-control eating was assembled by reviewing qualitative literature, clinical descriptions, and research on binge eating. Eating disorder experts (n = 34) and eating disorder clients (n = 22) rated each proposed item's clarity and relevance to the construct of loss-of-control eating, rated 13 facets for their relevance to the construct, and provided open-ended feedback about the items and facets. Based on the experts' and clients' quantitative and qualitative feedback, scale items were clarified, 28 items were added, and 10 were deleted. University students (n = 476; 70% female, mean age = 20.4 years) completed the resulting 74-item questionnaire, rating how often they had the experience identified in the item while eating in the last 4 weeks. They also completed the measures of eating disturbance, general distress, functional impairment, and general self-control.

RESULTS

The resulting 24-item LOCES (Cronbach's α = .96) retained items with highest item-total correlations and coverage of the 12 construct facets that experts rated as important. The LOCES was significantly correlated with eating disturbances, general distress, functional impairment, and general self-control. Three subfactors were identified: behavioral, cognitive/dissociative, and positive/euphoric aspects of loss-of-control eating. A brief, seven-item version of the LOCES was developed and validated.

DISCUSSION

A thorough process of development, content validation, and psychometric evaluation in multiple samples yielded the multifaceted LOCES and its brief form. These instruments may be useful in assessing loss-of-control eating in both clinical and nonclinical settings.

Comparing Japanese College Students’ and U.S. College Students’ Disordered Eating, Distress, and Psychological Inflexibility

The present study investigated whether psychological inflexibility is related to disordered eating in Japanese undergraduate students and compared the strength and pattern of the associations with effects in a sample of undergraduate students from the United States. Data from 200 Japanese ( nfemale = 100) and 481 U.S. ( nfemale = 380) college students were used. Contrary to prediction, female gender and higher body mass index (BMI), but not psychological inflexibility, were uniquely related to higher levels of disordered eating while controlling for age and psychological distress in the Japanese group. In the U.S. group, greater psychological inflexibility was the only variable that was uniquely related to higher levels of disordered eating after controlling for other study variables. Our findings suggest that psychological inflexibility may not be a useful concept for understanding disordered eating within Japanese college students.

Somatic involvement assessed through a cumulative score of clinical severity in patients with eating disorders

PURPOSE

To evaluate the overall somatic involvement in patients with eating disorders (EDs).

METHODS

The medical records of 206 patients (age 15-56 years, 96.1% females) with diagnosis of anorexia nervosa (AN, n = 63, 30.6%), bulimia nervosa (BN, n = 78, 37.9%), or eating disorder not otherwise specified (EDNOS, n = 65, 31.6 %) were analyzed. A cumulative score of clinical severity (SCS) was computed according to the presence of physical, instrumental, and laboratory abnormalities, as well as to their prognostic impact. Based on the tertile distribution of SCS, three levels of severity were defined: low, medium, and high.

RESULTS

A medium/high level of severity was found in 63% of the whole sample, 89% of AN, 49% of BN, and 55% of EDNOS. In the whole sample, the risk of medium/high SCS was significantly and inversely related to the body mass index (BMI) and to the lifetime minimum BMI. The severity level was significantly and positively associated with diagnosis of AN, duration of amenorrhea C1 year, and presence of ED-related symptoms. EDNOS patients showed a higher risk for increased SCS than BN patients, although not significantly.

CONCLUSION

The non-negligible frequency of a relevant somatic involvement in patients with EDNOS suggests that a transdiagnostic scoring system might be helpful to identify ED cases at risk of medical complications.

The diagnostic classification of eating disorders: current situation, possible alternatives and future perspectives

The current nosography of eating disorders (ED) has various limitations in terms of validity and accuracy. The changes adopted in the DSM-5 limit some of the current problems, such as excessive prevalence of ED not otherwise specified (EDNOS) and the lack of longitudinal stability, but are unlikely to adequately capture the clinical complexity of ED. Many authors suggest the need for a thorough review of the current nosography to support evidence-based classification. In this paper, we discuss the validity of the current diagnostic categories and their possible reorganization. Furthermore, we review the main empirical models of classification and the diagnostic approach from a personality perspective, with particular attention to research and to the prognostic and therapeutic implications.

Incorporating dimensions into the classification of eating disorders: three models and their implications for research and clinical practice

OBJECTIVE

Given renewed interest in dimensional approaches in psychiatric nosology, we review evidence for the utility of including dimensions of eating disorder (ED) psychopathology, comorbid psychopathology, and neurobiology in the classification of EDs.

METHOD

We searched on-line databases and reference lists of published papers for articles on dimensional methods in psychiatric classification, with an emphasis on EDs.

RESULTS

ED classification may be enhanced by including dimensional assessments. Specifically, some ED features appear to exist on a continuum with normality, and dimensional measures of ED severity are likely to have utility in clinical contexts. Furthermore, accumulating data support the validity of ED classification schemes that incorporate dimensions of comorbid psychopathology. Finally, neurobiological dimensions have gained increasing notice across the psychiatric literature and may be particularly salient to the classification of EDs.

DISCUSSION

An approach to ED classification that incorporates multiple dimensional measures may have the greatest utility for advancing ED treatment.

Food-related impulsivity in obesity and binge eating disorder--a systematic review

Impulsivity towards food has been recognized as a potential factor leading to increased food intake in obesity. Patients suffering from binge eating disorder (BED) form a specific subgroup of obese people that might be characterized by increased impulsivity. These assumptions, although, have yet to be verified. Therefore, this review evaluates evidence for food-related impulsivity in obese people with and without BED and examines possible differences between both populations. More precisely, evidence for the two components of impulsivity is analyzed separately: evidence for reward sensitivity, specifically, the urge for appetitive stimuli and evidence for rash-spontaneous behaviour such as acting disinhibited with no regard for the consequences. Our search resulted in 51 articles demonstrating generally increased food-related impulsivity. We found particular emphasis on increased reward sensitivity in obese people, which appeared to be more pronounced in people with BED. There was little and conflicting evidence, however, concerning increased rash-spontaneous behaviour in obese people without BED, but consistent evidence of an increase in obese people with BED. All in all, the evidence supports the view that BED represents a specific phenotype of obesity with increased food-related impulsivity. Taking these specific deficits into account can enhance the effectiveness of weight reduction programmes and psychotherapy.

Latent profile and latent transition analyses of eating disorder phenotypes in a clinical sample: a 6-year follow-up study

The DSM-IV classification of Eating Disorders (EDs) identifies clinical entities showing considerable overlap and diagnostic instability across time. Latent profile analysis (LPA) allows the identification of underlying groups of individuals according to their patterned responses across a set of features. LPA was applied to data regarding EDs symptoms of a clinical sample of 716 EDs patients, with a current DSM-IV diagnosis of threshold and subthreshold EDs. Latent transition analysis (LTA) was used to examine the longitudinal stability of the obtained profiles. The latent profiles were compared for psychopathological variables and long-term outcomes (recovery, relapse), based on a 6-year follow-up after a cognitive behavioural treatment. Five different phenotypes were identified: "severe binging", "moderate binging", "restricted eating", "binge and moderate purging", and "binge and severe purging". The relevance of this characterization was confirmed by the differences in terms of psychopathological features and outcomes. Over the long term, a three-profile solution was adopted, clustering the subjects into "binge eating", "binge eating and purging", and "restricted eating". Latent profiles showed a moderate stability over the 6-year period, with probability estimates of stability within status over time of 0.57 for "binge eating", 0.40 for "binge eating and purging", and 0.41 for "restricted eating". The implications for DSM 5 were discussed, and the relative high rate of transition within phenotypes confirmed the significant instability of EDs phenomenology.

Evaluating new severity dimensions in the DSM-5 for bulimic syndromes using mixture modeling

OBJECTIVE

Proposed DSM-5 severity dimensions reveal ambiguity regarding the extent to which certain features define boundaries between similar diagnoses or represent underlying dimensions within a broader category of bulimic syndromes. The current study utilized a novel mixed modeling approach that can simultaneously model latent dimensions and latent categories to address this ambiguity.

METHOD

Data from structured clinical interviews in 528 adult participants were analyzed.

RESULTS

A three-class solution with one severity dimension that was invariant across groups provided the best-fitting model. Both latent Classes 1 and 2 included bulimic syndromes but were distinguished by greater purging and weight phobia in latent Class 1. Latent Class 3 resembled a noneating disorder class. External validation analyses supported significant differences among empirically derived groups.

DISCUSSION

Weight phobia contributes to categorical distinctiveness among bulimic syndromes whereas other features (purging, binge eating, and weight) may do so only in specific combinations. Uniform severity criteria may be appropriate across bulimic syndromes.

Subtypes in bulimia nervosa: the role of eating disorder symptomatology, negative affect, and interpersonal functioning

BACKGROUND

The aim of the study was to investigate whether patients with bulimia nervosa (BN) could be subdivided into clinically meaningful groups reflecting the complex patterns of eating disorder symptoms and personality characteristics that face the clinician.

METHODS

Seventy patients diagnosed with BN using the Eating Disorder Examination were assessed with measures of negative affect, attachment patterns, and interpersonal problems. An exploratory hierarchical cluster analysis was performed.

RESULTS

The study found two main subtypes differing primarily in terms of symptom severity and level of negative affect, but these subtypes were further subdivided into four clinically relevant subtypes: A dietary restraint/negative affect/high symptomatic group, an emotionally overcontrolled group, a low dietary restraint/emotionally underregulated group, and a high functioning/securely attached group.

CONCLUSIONS

The study indicates that cluster-analytic studies, including a broad range of instruments measuring eating disorder symptoms as well as negative affect, relational patterns, and other personality characteristics, may contribute to an integration of previously suggested models of subtypes in BN.

Predicting interest in liposuction among women with eating problems: a population-based study

The purpose of this paper was to examine predictors of an interest in liposuction among women with eating problems. A questionnaire was sent to 3500 women aged 18-35 years, whereof 378 of 1861 responders screened positively on eating problems. Assessments included sociodemographic status, social network, physical exercise, attitudes towards cosmetic surgery, teasing history, body dysmorphic disorder-like symptoms, body image, self-esteem, personality, interpersonal attachment and emotional distress. Fifty-two percent reported an interest in liposuction, which was independently predicted by appearance orientation, appearance evaluation, being critical/quarrelsome, teasing history, wish for a better relationship with father, low education and being unmarried. Predictors differed somewhat from those previously found in the general population. Considering that our sample consisted of women with self-reported eating problems, the association between liposuction and eating behaviors should be further examined in a sample of patients with a formal eating disorder diagnosis.

Effects of an Internet-based intervention for subthreshold eating disorders: a randomized controlled trial

BACKGROUND

Women reporting initial eating disorder (ED) symptoms are at highest risk for the development of an eating disorder. Preventive interventions should, therefore, be specifically tailored for this subgroup.

AIMS

To adapt and evaluate the effects of the Internet-based prevention program "Student Bodies™" for women with symptoms of disordered eating and/or subthreshold eating disorder (ED) syndromes.

METHOD

126 women, reporting subthreshold ED symptoms (high weight and shape concerns and below threshold bingeing, purging, chronic dieting or several of these symptoms) were randomly assigned to a Student Bodies™+ (SB+) intervention or a wait-list control group and assessed at pre-intervention, post-intervention, and 6-month follow-up. "Student Bodies™" was adapted to be suitable for subthreshold EDs. Main outcome measures were attitudes and symptoms of disordered eating. Pre-follow-up data were analyzed by ANCOVAS with mixed effects.

RESULTS

At 6-month follow-up, compared to participants in the control group, participants in the intervention group showed significantly greater improvements on ED-related attitudes. Intervention participants also showed 67% (95% CI = 20-87%) greater reductions in combined rates of subjective and objective binges, and 86% (95% CI = 63-95%) greater reduction in purging episodes. Also, the rates of participants abstinent from all symptoms of disordered eating (restrictive eating, binge eating and any compensatory behavior) were significantly higher in the intervention group (45.1% vs. 26.9%). Post-hoc subgroup analyses revealed that for participants with binge eating the effect on EDE-Q scores was larger than in the pure restricting subgroup.

CONCLUSION

The adapted "SB+" program represents an effective intervention for women with subthreshold EDs of the binge eating subtype.

Examining the stability of DSM-IV and empirically derived eating disorder classification: implications for DSM-5

OBJECTIVE

The purpose of this investigation was to derive an empirical classification of eating disorder symptoms in a heterogeneous eating disorder sample using latent class analysis (LCA) and to examine the longitudinal stability of these latent classes (LCs) and the stability of DSM-IV eating disorder (ED) diagnoses.

METHOD

A total of 429 females with ED symptoms were assessed using the Eating Disorder Examination every 6 months for 2 years. LCA was used to derive empirical classification at baseline. Latent transition analysis (LTA) was used to examine the longitudinal stability of LCs, and Markov modeling procedures were used to examine DSM-IV ED diagnoses over all the time points.

RESULTS

LCA yielded a 3-class solution: binge eating and purging, binge eating only, and low body mass index. LTA indicated that these LCs showed greater stability over 2 years than DSM-IV diagnoses with the probability of remaining in the same class ranging from 0.69 to 0.91 for LCs and from 0.40 to 0.75 for DSM-IV diagnoses. Transition patterns also revealed more stability for LCs with only 21% changing classes compared with 63% of the DSM-IV diagnostic categories.

CONCLUSION

Empirically derived classes of ED symptoms showed greater longitudinal stability than DSM-IV diagnoses over a 2-year time period, suggesting that modifying the criteria to be consistent with empirically based classification (e.g., reducing frequency requirements of binge eating and purging) may reduce ED diagnostic crossover in DSM-5.

Eating disorders and exercise: a structural equation modelling analysis of a conceptual model

OBJECTIVE

Despite the well-established health benefits of physical activity, the role of exercise for eating disorders (ED) is controversial; thus dictating a need for a better understanding of the mechanisms of exercise and ED. The purpose of our study was to examine a conceptual model that hypothesizes regular exercise without psychological compulsion might impart beneficial effects for preventing and treating ED.

METHOD

University students (N = 539) completed self-report assessments of quality of life, exercise level, ED risk and exercise dependence symptoms. Structural equation modelling analysis was undertaken to examine the conceptual model's proposed relationships.

RESULTS

Mediation analysis and model comparison tests showed that the partially mediated model without the physical well-being latent construct fit the data best.

DISCUSSION

Our results provided initial support for the conceptual model by showing that the psychological benefits, but not the physical benefits, conveyed by exercise were associated with reduced ED risk.

Social cognition in eating disorders: encoding and representational processes in binging and purging patients

OBJECTIVE

The present study investigates social cognition impairments in 29 women with bingeing/purging spectrum eating disorders (ED) compared to 27 healthy controls.

METHOD

Measures were used to examine encoding and representational processes in relation to affect perception and affect attribution, as well as the ability to recognize mental causality in social relationships.

RESULTS

ED patients failed to correctly encode causality in interpersonal relations, exhibited deficits in their ability to ascribe behaviour to mental states, and showed a greater tendency to attribute negative affects in interpersonal relationships. Stepwise regression analyses suggested that ED symptoms could account for deficits in the recognition of causality in interpersonal relations.

CONCLUSIONS

In addition to addressing ED symptoms, social cognition deficits should be addressed in the psychological treatment of EDs.

Addressing the EDNOS issue and improving upon the utility of DSM-IV: classifying eating disorders using symptom profiles

OBJECTIVE

To compare the descriptive and clinical utility of two classification systems: DSM-IV eating disorder diagnoses and proposed symptom profiles. The symptom profiles are based on the presence of overvalued ideas about shape/weight, as well as combinations of three key eating disorder symptoms (e.g. body mass index (BMI) above or below threshold and the presence or absence of bingeing and purging behaviours).

METHOD

The two systems were compared on their ability to offer descriptively useful information in classifying individuals with eating disorders. In addition, we examined our system's unique contribution to clinical outcome and its relation to readiness for change.

RESULTS

Classifying individuals via symptom profiles provided information about eating disorder not otherwise specified (EDNOS), a prevalent, heterogeneous and under-researched diagnostic category. Symptom profiles outperformed the DSM-IV diagnostic system in the ability to account for variation in patients' decision to enrol in treatment, performing comparably to readiness for change.

CONCLUSION

Classifying individuals according to symptom profile and readiness for change appears to have more descriptive and clinical utility than the current diagnostic system.

Stability and change in patterns of concerns related to eating, weight, and shape in young adult women: a latent transition analysis

Although college women are known to be at high risk for eating-related problems, relatively little is known about how various aspects of concerns related to eating, weight, and shape are patterned syndromally in this population. Moreover, the extent to which various patterns represent stable conditions or transitory states during this dynamic period of development is unclear. The present study used latent class and latent transition analysis (LCA/LTA) to derive syndromes of concerns related to eating, weight, and shape and movement across these syndromes in a sample of 1,498 women ascertained as first-time freshmen and studied over 4 years. LCA identified 5 classes characterized by (a) no obvious pathological eating-related concerns (prevalence: 28%-34%); (b) a high likelihood of limiting attempts (prevalence: 29%-34%); (c) a high likelihood of overeating and binge eating (prevalence: 14%-18%); (d) a high likelihood of limiting attempts and overeating or binge eating (prevalence: 14%-17%); and (e) pervasive bulimic like concerns (prevalence: 6%-7%). Membership in each latent class tended to be stable over time. When movement occurred, it tended to be to a less severe class. These findings indicate that there are distinct, prevalent, and relatively stable forms of eating-related concerns in college women.

Are diagnostic criteria for eating disorders markers of medical severity?

OBJECTIVE

The objective of this study was to compare the medical severity of adolescents who had eating disorders not otherwise specified (EDNOS) with those who had anorexia nervosa (AN) and bulimia nervosa (BN).

METHODS

Medical records of 1310 females aged 8 through 19 years and treated for AN, BN, or EDNOS were retrospectively reviewed. Patients with EDNOS were subcategorized into partial AN (pAN) and partial BN (pBN) when they met all Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria but 1 for AN or BN, respectively. Primary outcome variables were heart rate, systolic blood pressure, temperature, and QTc interval on electrocardiogram. Additional physiologically significant medical complications were also reviewed.

RESULTS

A total of 25.2% of females had AN, 12.4% had BN, and 62.4% had EDNOS. The medical severity of patients with EDNOS was intermediate to that of patients with AN and BN in all primary outcomes. Patients with pAN had significantly higher heart rates, systolic blood pressures, and temperatures than those with AN; patients with pBN did not differ significantly from those with BN in any primary outcome variable; however, patients with pAN and pBN differed significantly from each other in all outcome variables. Patients with pBN and BN had longer QTc intervals and higher rates of additional medical complications reported at presentation than other groups.

CONCLUSIONS

EDNOS is a medically heterogeneous category with serious physiologic sequelae in children and adolescents. Broadening AN and BN criteria in pediatric patients to include pAN and pBN may prove to be clinically useful.

Broad categories for the diagnosis of eating disorders (BCD-ED): an alternative system for classification

OBJECTIVE

Eating Disorder Not Otherwise Specified (EDNOS), a residual category in DSM-IV, is the most commonly used eating disorder diagnosis in clinical settings. A diagnostic scheme, termed Broad Categories for the Diagnosis of Eating Disorders (BCD-ED), is proposed to diminish use of the EDNOS category while preserving the existing eating disorder categories. The objective of this review was to examine the advantages and disadvantages of adopting this scheme for DSM-V.

METHOD

We reviewed published studies to assess the proportion of individuals with DSM-IV EDNOS that would be reclassified under the BCD-ED system, support for the hierarchy of the three categories, and the potential risk of "overdiagnosis."

RESULTS

Adopting the BCD-ED scheme would have both advantages and disadvantages, but would likely substantially reduce the number of individuals who would receive an EDNOS diagnosis.

DISCUSSION

BCD-ED is a potential method of addressing the high frequency of EDNOS, but would be a major change in how eating disorders are categorized.

Sex differences in sum scores may be hard to interpret: the importance of measurement invariance

In most assessment instruments, distinct items are designed to measure a trait, and the sum score of these items serves as an approximation of an individual's trait score. In interpreting group differences with respect to sum scores, the instrument should measure the same underlying trait across groups (e.g., male/female, young/old). Differences with respect to the sum score should accurately reflect differences in the latent trait of interest. A necessary condition for this is that the instrument is measurement invariant. In the current study, the authors illustrate a stepwise approach for testing measurement invariance with respect to sex in a four-item instrument designed to assess disordered eating behavior in a large epidemiological sample (1,195 men and 1,507 women). This approach can be applied to other phenotypes for which group differences are expected. Any analysis of such variables may be subject to measurement bias if a lack of measurement invariance between grouping variables goes undetected.

An examination of the overlap between genetic and environmental risk factors for intentional weight loss and overeating

OBJECTIVE

To further our understanding of how intentional weight loss (IWL) and overeating are related, we examined the shared genetic and environmental variance between lifetime IWL and overeating.

METHOD

Interview data were available for 1,976 female twins (both members of 439 and 264 pairs of monozygotic and dizygotic twins, respectively), mean age = 40.61, SD = 4.72. We used lifetime diagnostic data for eating disorders obtained from a semistructured psychiatric telephone interview, examined in a bivariate twin analysis. Both lifetime behaviors were measured on a 3-point scale, where absence of IWL or overeating formed one anchor on the scale and lifetime anorexia nervosa (AN) and bulimia nervosa (BN) formed the opposite anchors, respectively.

RESULTS

In line with previous findings, a higher body mass index was significantly associated with the lifetime presence of IWL and/or overeating (odds ratio = 1.13, 95% confidence interval (CI): 1.08-1.19). The best fitting twin model contained additive genetic and nonshared environmental influence influencing both IWL and overeating, with correlations between these influences of 0.61 (95% CI: 0.35-0.92) and 0.24 (95% CI: 0.07-0.42), respectively.

DISCUSSION

About 37% of genetic risk factors were considered to overlap between IWL and overeating, and with only 6% of overlap between environmental risk factors. Thus, considerable independence of risk factors was indicated.

The epidemiology of eating disorders in six European countries: results of the ESEMeD-WMH project

Few data are available to estimate the prevalence of eating disorders (EDs) and their correlates in the community. This paper reports data on EDs obtained in the framework of the ESEMeD project, aimed at investigating the prevalence of non-psychotic mental disorders in six European countries (Belgium, France, Germany, Italy, the Netherlands and Spain), using a new version of the Composite International Diagnostic Interview. The ESEMeD study was a general population cross-sectional household survey. In total, 21,425 respondents aged 18 or older provided data for the project between January 2001 and August 2003. A subsample (N=4139) underwent a detailed investigation on EDs. Lifetime estimated prevalence of anorexia nervosa, bulimia nervosa, binge eating disorder, sub-threshold binge eating disorder, and any binge eating were 0.48%, 0.51%, 1.12%, 0.72%, and 2.15%, respectively, and they were 3-8 times higher among women for all EDs. However, since people under 18 were excluded from this study, our prevalence should be taken as lower-bound estimate of real frequencies. Indeed, cumulative lifetime prevalence analysis showed that the majority of eating disorders had their initial onset between 10 and 20 years of age. Role impairment and comorbidity with other mental disorders were highly common, yet only small proportions of patients with a lifetime diagnosis of EDs requested medical treatment. It still has to be proven whether early diagnostic identification and access to specialized care can reduce the burden caused by these disorders.

Typical and atypical restrictive anorexia nervosa: weight history, body image, psychiatric symptoms, and response to outpatient treatment

OBJECTIVE

Few studies have examined the characteristics of atypical restrictive anorexia nervosa (AN) with a well-powered design. The study aims to explore this issue, with particular attention paid to psychopathology and response to outpatient treatment.

METHOD

The sample consists of 365 participants with restrictive AN and 204 with atypical AN. Three types of atypical AN were included: subthreshold (all the criteria except weight); partial (AN without amenorrhea); and participants with AN without fear of gaining weight.

RESULTS

Participants with AN without fear of weight gain reported the lowest lifetime BMI and subthreshold AN the highest. Participant with partial AN reported the highest levels of psychiatric symptoms and novelty seeking. All types of atypical AN showed high rates of dropout, whereas participants with subthreshold AN showed the highest level of full remission after treatment.

DISCUSSION

Before considering a revision of the diagnostic criteria of AN, further studies on adequately large samples are needed.