Impulsivity-related traits distinguish women with co-occurring bulimia nervosa in a psychiatric sample

Temperament impact on eating disorder symptoms and habit formation: a novel model to inform treatment

BACKGROUND

Temperament has long been described as the biological dimension of personality. Due to advancing brain-imaging technology, our understanding of temperament has deepened and transformed over the last 25 years. Temperament combines genetic, neurobiological and trait research. Temperament has been included peripherally in some eating disorder (ED) treatment approaches but has been ignored by most. Temperament fills a fundamental treatment gap by clarifying who is more vulnerable to develop ED and why some individuals are susceptible to specific ED symptoms while others are not. In addition, temperament targets possible treatment solutions.

MAIN TEXT

There is a need for a novel model that incorporates and explores the role of temperament in ED treatment intervention. This paper is a metaphoric temperament model to inform treatment intervention. It describes how temperament traits influences new decisions which impact new behavioural responses. In turn, it neurobiologically tracks how and why the brain efficiently transforms new decisions into new habits. This model integrates both temperament and habit research to explore (a) what temperament is; (b) how new decisions develop into habits neurobiologically; (c) that the brain wires destructive symptoms into habits in the same way that it wires healthy/productive behaviours into habits; (d) traits that trigger ED symptoms are the same traits that influence productive behaviours; and in regard to treatment implications (e) when treatment structure and intervention target client temperaments, the potential for new healthy "trait-syntonic" habits could develop.

CONCLUSIONS

This paper introduces a metaphoric model that synthesizes and integrates temperament neurobiological and trait findings with ED symptoms, habits, and client trait-based solutions. The model synthesizes and integrates different research domains to establish a brain-based foundation to inform treatment intervention. The model targets clients' temperament traits as central collections of innate self-expressions that could be utilized as tools to redirect client trait-syntonic ED responses into trait-syntonic productive outcomes. The brain bases of temperament and habit formation serve as a biological foundation for ED treatment intervention.

Risk factors for eating disorders: findings from a rapid review

BACKGROUND

Risk factors represent a range of complex variables associated with the onset, development, and course of eating disorders. Understanding these risk factors is vital for the refinement of aetiological models, which may inform the development of targeted, evidence-based prevention, early intervention, and treatment programs. This Rapid Review aimed to identify and summarise research studies conducted within the last 12 years, focusing on risk factors associated with eating disorders.

METHODS

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

RESULTS

A total of 284 studies were included. The findings were divided into nine main categories: (1) genetics, (2) gastrointestinal microbiota and autoimmune reactions, (3) childhood and early adolescent exposures, (4) personality traits and comorbid mental health conditions, (5) gender, (6) socio-economic status, (7) ethnic minority, (8) body image and social influence, and (9) elite sports. A substantial amount of research exists supporting the role of inherited genetic risk in the development of eating disorders, with biological risk factors, such as the role of gut microbiota in dysregulation of appetite, an area of emerging evidence. Abuse, trauma and childhood obesity are strongly linked to eating disorders, however less conclusive evidence exists regarding developmental factors such as role of in-utero exposure to hormones. Comorbidities between eating disorders and mental health disorders, including personality and mood disorders, have been found to increase the severity of eating disorder symptomatology. Higher education attainment, body image-related factors, and use of appearance-focused social media are also associated with increased risk of eating disorder symptoms.

CONCLUSION

Eating disorders are associated with multiple risk factors. An extensive amount of research has been conducted in the field; however, further studies are required to assess the causal nature of the risk factors identified in the current review. This will assist in understanding the sequelae of eating disorder development and in turn allow for enhancement of existing interventions and ultimately improved outcomes for individuals.

The relationship between disordered eating behaviour and the five factor model personality dimensions: A systematic review

The relationship between personality and eating disorders has received significant research attention. This review aimed to synthesize research regarding the Five Factor Model (FFM) and disordered eating behaviors, to gain an improved understanding of the relationship between normal-range personality and subclinical eating disorders. Electronic Databases were used to identify studies published in English that utilized self-report measures of disordered eating and the FFM. A qualitative synthesis of 45 papers was then conducted. High scores on Neuroticism were associated with increased disordered eating behavior. Different disordered eating behaviors were found to have unique relationships with personality dimensions. Facets within domains varied in direction of correlation with disordered eating behaviors, particularly in the Agreeableness, Contentiousness, and Openness domains. The results indicate that, further research is needed before generalizing treatment approaches for eating disorders for females, males, and gender diverse populations.

Threat appraisal partially mediates the relation between neuroticism and bulimic symptoms

Several studies support an association between neuroticism and bulimic symptoms; however, few studies have focused on how neuroticism exerts its influence. The purpose of this study was to extend the literature by investigating threat appraisal as a potential mediator of the relation between neuroticism and bulimic symptoms. One hundred and twenty women completed self-report measures of trait neuroticism, threat appraisal, and bulimic symptoms. Approximately half of the sample reported moderate or high levels of bulimic symptoms. Bootstrapping analyses revealed that neuroticism and threat appraisal were both positive predictors of bulimic symptoms. Further, threat appraisal partially mediated the association between neuroticism and bulimic symptoms. The findings suggest that women high in neuroticism may be vulnerable to experiencing bulimic symptoms, particularly during periods of heightened stress. These women may perceive bulimic behavior to be more effective in alleviating negative stressful emotions compared to more adaptive coping strategies. Based on the findings, women diagnosed with bulimia nervosa with high levels of neuroticism may benefit from interventions that specifically target threat appraisals to facilitate their ability to effectively adapt to stress.

Comparing the Personality Traits of Patients with an Eating Disorder versus a Dual Diagnosis

Objectives: This cross-sectional study explored personality traits of individuals receiving treatment in a private clinic for an eating disorder (ED) compared to those receiving treatment for a dual diagnosis (DD; defined as an addiction to illegal drugs and/or alcohol along with a mental illness, in this case an ED). The aims of this study were to: (a) assess the personality profiles and differentiating traits between the ED and DD groups, (b) analyze differences in personality traits of restrictive ED versus bingeing ED profiles, and lastly (c) compare the individuals Temperament and Character Inventory-Revised (TCI-R) results to their personality clusters as per the Diagnostic and Statistical Manual of Mental Disorders - 5^th edition (DSM-5). Methods: The TCI-R is a self-report questionnaire consisting of seven scales, each with their own subscales, which provide a fuller understanding of each temperament and character trait evaluated. This questionnaire was given to patients (n = 67) receiving treatment at a private institute specialized in eating disorders in Barcelona, Spain and the surrounding areas, along with the State-Trait Anxiety Inventory (STAI), Beck Depression Inventory-II (BDI-II), and the Barratt Impulsiveness Scale-11 (BIS-11). These subsequent questionnaires were given as they are often found to be comorbidities of ED. Results: The ED group (n = 41), regarding the TCI-R scales, showed higher scores in harm avoidance (HA), reward dependence (RD), persistence (P), cooperativeness (C) and self-directedness (SD). Whereas, the DD (n = 26) group, showed higher scores in novelty seeking (NS) and self-transcendence (ST). Also, there was a significant positive correlation between the DD group and the extravagance (NS3) subscale of novelty seeking across models. When comparing the two ED groups, the restrictive profile (RP) to the bingeing profile (BP), there were significant negative correlations in the TCI-R subscales of dependence (RD4) and perfectionism (P4) whereas there were positive correlations in the TCI-R subscale of responsibility (SD1). Conclusions: These results support previous studies and help to appraise differences in personality traits between specific groups in a clinical setting.

Understanding the genetics and epigenetics of bulimia nervosa/bulimia spectrum disorder and comorbid borderline personality disorder (BN/BSD-BPD): a systematic review

PURPOSE

To evaluate and understand the genetic and epigenetic basis of bulimia nervosa/bulimia spectrum disorder and comorbid borderline personality disorder (BN/BSD-BPD).

METHODS

The present systematic review was conducted in accordance to PRISMA guidelines. Advanced systematic searches of Medline, EMBASE, PsychINFO, Web of Science, Scopus, CINHAL plus, and the Cochrane Library were conducted using the search terms 'bulimia nervosa', 'bulimia spectrum disorder', 'borderline personality disorder', 'genes', and 'genetics'. The search strategy garnered seven studies for inclusion in the present review.

RESULTS

Women with BN/BSD-BPD had significantly lower serotonin and monoamine oxidise activity compared to women with BN/BSD or healthy controls (HC). As well, women with BN/BSD-BPD displayed elevated methylation of the dopamine receptor gene promoter, brain-derived neurotrophic factor, and changes in the methylation of the glucocorticoid receptor gene promoter (NR3C1) compared to women with BN/BSD and HC. The results also demonstrated that rates of childhood sexual abuse and childhood physical abuse are higher in those with BN/BSD-BPD than those with BN/BSD and HC, and that these types of abuse are often correlated with the methylation differences seen in BN/BSD-BPD women.

CONCLUSION

Due to the differences observed between individuals with BN/BSD-BPD and those with BN/BSD and HC a genetic/epigenetic aetiological model of BN/BSD-BPD was developed and is proposed in this review. This evidence-based model visually illustrates the current state of the field and draws attention to the need for subsequent research.

Personality Variables and Eating Pathology

Personality variables have long been implicated in the onset and maintenance of eating disorders, as well as in symptom divergence between anorexia nervosa and bulimia nervosa. Clinical observations are broadly supported by the data, with restricting anorexia nervosa associated with higher levels of constraint and Persistence, and binge-purge behaviors linked to the tendency to take impulsive action when emotionally distressed. Considerable heterogeneity is found within diagnostic categories, however, suggesting that different personality structures may predispose individuals to develop disordered eating through alternative pathways.

Emerging Treatments in Eating Disorders

Eating disorders (EDs), including anorexia nervosa, bulimia nervosa, and binge-eating disorder, constitute a class of common and deadly psychiatric disorders. While numerous studies in humans highlight the important role of neurobiological alterations in the development of ED-related behaviors, the precise neural substrate that mediates this risk is unknown. Historically, pharmacological interventions have played a limited role in the treatment of eating disorders, typically providing symptomatic relief of comorbid psychiatric issues, like depression and anxiety, in support of the standard nutritional and psychological treatments. To date there are no Food and Drug Administration-approved medications or procedures for anorexia nervosa, and only one Food and Drug Administration-approved medication each for bulimia nervosa (fluoxetine) and binge-eating disorder (lisdexamfetamine). While there is little primary interest in drug development for eating disorders, postmarket monitoring of medications and procedures approved for other indications has identified several novel treatment options for patients with eating disorders. In this review, I utilize searches of the PubMed and ClinicalTrials.gov databases to highlight emerging treatments in eating disorders.