Alexithymia may explain the relationship between autistic traits and eating disorder psychopathology

Potential mechanisms underlying the association between feeding and eating disorders and autism

There is a reliable association between autism and Feeding and Eating Disorders. Concerningly, where these two conditions co-occur, clinical outcomes of Feeding and Eating Disorders are significantly worse, and treatment less effective, than when the Feeding and Eating Disorders occur in neurotypical individuals. Problematically, the reason for the association between autism and Feeding and Eating Disorders is poorly understood, which constrains advances in clinical care. This paper outlines several possible mechanisms that may underlie the observed association and suggests ways in which they may be empirically tested. Mechanisms are split into those producing an artefactual association, and those reflecting a genuine link between conditions. Artefactual associations may be due to conceptual overlap in both diagnostic criteria and measurement, Feeding and Eating Disorders causing transient autistic traits, or the association being non-specific in nature. A genuine association between autism and Feeding and Eating Disorders may be due to common causal factors, autism directly or indirectly causing Feeding and Eating Disorders, and Feeding and Eating Disorders being a female manifestation of autism.

Indistinguishable behavioural and neural correlates of perceptual self-other distinction in autistic and neurotypical adults

Previous research has suggested that self-bias (i.e., enhanced cognitive processing of self-versus other-relevant information) may be atypical in autism spectrum conditions (ASC), perhaps due to difficulties with self-other distinction. However, empirical evidence for this is inconsistent, and the neural basis of processing differences remains unknown. We present two experiments that aimed to test perceptual self-bias and familiarity effects in ASC using a perceptual-association task. Participants were asked to distinguish face/label associations of the self from those of other people of differing levels of familiarity (i.e., friend vs stranger). Experiment 1 took an individual differences approach by testing whether behavioural self-bias is associated with the number of autistic traits in a neurotypical adult sample (N = 59). Experiment 2 took a case-control approach by testing whether behavioural self-bias and associated ERP responses differ between neurotypical (N = 27) and autistic (N = 30) adults. Across both experiments, behavioural results showed that participants experienced a self-bias (self > friend and stranger) and a familiarity effect (e.g., friend > stranger); neither effect was affected by the number of autistic traits or autism diagnosis. In Experiment 2, analysis of N1, N2, and P3 ERP components revealed a typical self-bias in both groups (self distinct from friend and stranger), and only the autistic group showed evidence of a familiarity effect (N2 more negative-going for stranger than friend). The findings are discussed in relation to self-other distinction ability, and the relevance of other neuropsychological and psychiatric conditions such as anxiety and alexithymia are also considered.

On Orthorexia Nervosa: A Systematic Review of Reviews

INTRODUCTION

Orthorexia nervosa (ON), characterized by a pathological preoccupation with "extreme dietary purity," is increasingly observed as a mental health condition among young adults and the general population. However, its diagnosis is not formally recognized and has remained contentious.

OBJECTIVE

In this systematic review, we attempt to overview previous reviews on ON, focusing on the methodological and conceptual issues with ON. This would serve both as a summary and a way to highlight gaps in earlier research.

METHODS

This systematic review took reference from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines, and using combinations of the search terms ("orthorexia" OR "orthorexia nervosa" OR "ON") AND ("review" OR "systematic review" OR "meta-analysis"), a literature search was performed on EMBASE, Medline and PsycINFO databases from inception up to October 31, 2023. Articles were included if (1) they were written or translated into English and (2) contained information pertaining to the diagnostic stability or validity of ON, or instruments used to measure ON symptoms and behaviors. Only review articles with a systematic literature search approach were included.

RESULTS

A total of 22 reviews were qualitatively reviewed. Several studies have reported variable prevalence of ON and highlighted the lack of thoroughly evaluated measures of ON with clear psychometric properties, with no reliable estimates. ORTO-15 and its variations such as ORTO-11, ORTO-12 are popularly used, although their use is discouraged. Existing instruments lack specificity for pathology and several disagreements on the conceptualization and hence diagnostic criteria of ON exist.

DISCUSSION

Previous reviews have consistently highlighted the highly variable (and contradictory) prevalence rates with different instruments to measure ON, lack of stable factor structure and psychometrics across ON measures, paucity of data on ON in clinical samples, and a need for a modern re-conceptualization of ON. The diagnosis of ON is challenging as it likely spans a spectrum from "normal" to "abnormal," and "functional" to "dysfunctional." "Non-pathological" orthorexia is not related to psychopathological constructs in the same way that ON is.

Challenges and opportunities for conceptualizing intuitive eating in autistic people

Although intuitive eating (IE) has become an increasingly adopted intervention target, current conceptualisations of IE have yet to pivot away from (neuro)normative physiology and phenomenology. Autistic individuals commonly report disordered eating behaviours and/or poorer well-being but appear to benefit from adaptive interventions using an affirmative approach. This article uses autism as a case example to summarise challenges related to IE's prevailing conceptualisation, before proposing how future research and current practice can be extended to the autistic population. Scholars are encouraged to evaluate the full 10-principal IE framework while utilising a participatory-led approach. We argue that research using a mixed methods design is urgently needed to comprehensively explore the (re)conceptualisation of IE in autistic people. While IE shows promise for producing positive outcomes in the autistic population, we discuss the potential challenges for research and practice due to its current emphasis on accurate interoception, emotional awareness and processing, and executive functioning. This suggests the need for research and practice to integrate autistic needs and experiences into future developments with an affirmative approach. Public Significance: IE is an effective intervention for reducing disordered eating behaviours. Autistic individuals commonly present disordered eating behaviours and have unique nutritional needs which often require intervention. However, there is limited understanding of IE among the autistic population. Research-informed definitions involving autistic perspectives will support translating the IE framework to this underrepresented population.

Longitudinal Associations Between Autistic Traits, Self-compassion, Anxiety and Depression in Autistic and Non-autistic Adults Without Intellectual Disability

PURPOSE

Previous cross-sectional research suggests self-compassion may mediate associations between autistic traits and mental health in autistic and non-autistic adults. However, no research to date has examined these relationships longitudinally. In this study, we used a cross-lagged panel analysis to examine correlations over time between autistic traits, self-compassion, and anxiety/depression.

METHODS

Participants were from the UK and included autistic (n = 228 at T1, n = 156 at T2, and n = 165 at T3) and non-autistic adults (n = 228 at T1, n = 122 at T2, and n = 124 at T3) without intellectual disability. Participants were recruited through an online participation platform and completed demographics, the Autism Spectrum Quotient (AQ), the Self-Compassion Scale (SCS), and the Hospital Anxiety and Depression Scale (HADS) at baseline (T1), 6 months (T2), and 12 months (T3).

RESULTS

In the autistic sample, negative correlations were observed between self-compassion and subsequent anxiety/depression across all models and timepoints, and these relationships were not reciprocal (i.e., earlier depression and anxiety did not predict future self-compassion). In the non-autistic sample, the findings generally suggested bi-directional relationships between self-compassion and anxiety/depression. In both groups, an indirect pathway between T1 autistic traits and T3 anxiety/depression via T2 self-compassion was confirmed.

CONCLUSION

Considering the high prevalence of anxiety and depression among autistic people, and that self-compassion can be cultivated through practice, these findings suggest that self-compassion could be a useful therapeutic target to promote mental health in the autistic population.

Psychosocial and neurocognitive correlates of suicidal thoughts and behaviours amongst siblings of persons with and without neurodevelopmental conditions

OBJECTIVE

Siblings of individuals with neurodevelopmental conditions (NDCs) have greater incidence of neuropsychiatric diagnoses and neurocognitive difficulties compared to siblings of persons without NDCs. Despite suicidality being labelled a global health crisis (WHO, 2014) and NDC siblings experiencing risk factors implicated in suicidality, no previous studies examined suicidality amongst adolescent and young adult siblings of persons with NDCs. Our study aimed to bridge this gap.

METHOD

The present study used Bayesian analyses and risk classification models to examine individual and environmental risk factors associated with suicidal thoughts and behaviours amongst siblings of persons with and without NDCs (n = 267; 132 NDC, 135 control group, mean age 20.61, range 14-27, 76.40% female, 76.78% White Caucasian), as measured using self-report survey data and remote self-administered cognitive tests.

RESULTS

NDC siblings had higher rates of current nonsuicidal self-injury (NSSI; 18.94% versus 14.07%, δ = -0.32), suicidal ideation (25.76% versus 8.89%, δ = -0.40) and history of suicide attempts (18.18% versus 4.44%, δ = -0.43) compared to controls. Classification models using boosting and random forest demonstrated adequate performance: positive predictive value 0.86-0.91, negative predictive value 0.81-0.90, false negative rates 0.11-0.24. Cognitive inflexibility, alexithymia, inattention, bullying, depression, NSSI, and eating or psychotic disorder history had the highest relative importance in predicting lifetime suicidality. Poorer executive functioning (measured by the Wisconsin Card Sorting Task, Sustained Attention to Response Task, Stop Signal Task, and N-Back 2-back task) was strongly correlated with suicidality.

CONCLUSIONS

Screening for proximal and modifiable risk factors is critical to inform suicidal behaviour intervention and prevention programs for at-risk siblings.

Sex-specific mechanisms for eating disorder risk in men and women with autistic traits: the role of alexithymia

BACKGROUND

A poorly understood relationship exists between eating disorders (ED) and autism spectrum conditions (ASC: henceforth 'autism'). ED are more prevalent in autistic people and people with high autistic traits, and autistic features are prognostic of longer illness. Aiming to understand what increases the risk of ED in relation to autism and autistic traits, previous research has implicated alexithymia as a causal mechanism in this relationship. These studies could not, however, disentangle whether alexithymia explains the relationship between ED pathology and autistic traits directly or through its impact on anxious/depressive symptoms, which in turn result in higher ED symptomatology. Moreover, despite evidence for sex differences in the aetiology of ED, little research has examined the impact of sex on these relationships.

METHODS

Focusing on the association between autistic traits and ED psychopathology, we examined independent mediating effects of alexithymia and anxious/depressive symptoms, as well as sequential mediation effects where alexithymia affects ED psychopathology via its impact on anxious/depressive symptoms. Participants were 198 men and 265 women with formally diagnosed and suspected ED, who completed an online survey of standardised scales.

RESULTS

In men, higher autistic traits were associated with ED psychopathology sequentially via greater alexithymia and through that, greater depressive/anxious symptoms. In women, alexithymia mediated the relationship between autistic traits and ED psychopathology both directly and sequentially through its impact on anxious/depressive symptoms. Interestingly, depressive/anxious symptoms also mediated that relationship independently from alexithymia.

CONCLUSIONS

While cross-sectional, these findings suggest that the relationship between autistic traits and ED symptomatology is mediated by other variables. In support of its proposed role in the aetiology of ED, alexithymia was directly associated with ED symptoms in women. It also affected ED symptoms indirectly, in all participants, via its effect on depressive/anxious symptoms. Interventions focusing on alexithymia may facilitate recovery not only via their effect on ED, but via their effect on other forms of state psychopathology which contribute to the maintenance and development of ED. Sex differences, however, reflect that alternative therapeutic targets for men and women may be beneficial.

Development and validation of a computer program for measuring emotional awareness in German-The geLEAS (German electronic Levels of Emotional Awareness Scale)

Introduction

Emotional awareness is the ability to identify, interpret, and verbalize the emotional responses of oneself and those of others. The Levels of Emotional Awareness Scale (LEAS) is an objective performance inventory that accurately measures an individual's emotional awareness. LEAS assessments are typically scored manually and are therefore both time consuming and cognitively demanding. This study presents a German electronic scoring program for the LEAS (geLEAS), the first non-English computerized assessment approach of the LEAS.

Methods

Data were collected from a healthy German community sample (N = 208). We developed a modern software for computerizing LEAS scoring, an open-source text-based emotion assessment tool called VETA (Verbal Emotion in Text Assessment). We investigated if the software would arrive at similar results as hand scoring in German and if emotional awareness would show similar associations to sociodemographic information and psychometric test results as in previous studies.

Results

The most frequently used scoring method of the geLEAS shows excellent internal consistency (α = 0.94) and high correlations with hand scoring (r = 0.97, p < 0.001). Higher emotional awareness measured by the geLEAS is associated with female gender, older age, and higher academic achievement (all p < 0.001). Moreover, it is linked to the ability to identify emotions in facial expressions (p < 0.001) and more accurate theory of mind functioning (p < 0.001).

Discussion

An automated method for evaluating emotional awareness greatly expands the ability to study emotional awareness in clinical care and research. This study aims to advance the use of emotional awareness as a clinical and scientific parameter.

What about males? Exploring sex differences in the relationship between emotion difficulties and eating disorders

OBJECTIVE

While eating disorders (EDs) are more commonly diagnosed in females, there is growing awareness that men also experience EDs and may do so in a different way. Difficulties with emotion processing and emotion regulation are believed to be important in EDs, but as studies have involved predominantly female samples, it is unclear whether this is also true for males.

METHODS

In a sample of 1604 participants (n = 631 males), we assessed emotion processing and emotion regulation in males with EDs (n = 109) and compared results to both females with EDs (n = 220) and males from the general population (n = 522). We also looked at whether emotion processing and emotion regulation difficulties predicted various aspects of eating psychopathology and whether this was moderated by sex. We assessed emotion processing with the Toronto Alexithymia Scale, emotion regulation with the Difficulties in Emotion Regulation Scale and the Emotion Regulation Questionnaire, and eating psychopathology with the Eating Disorder Examination Questionnaire.

RESULTS

We found that males with ED, like their female counterparts, suffered from emotion processing and emotion regulation deficits. We did find some sex differences, in that males with EDs tended to report more difficulties with their emotions as well as a more externally oriented thinking style compared to females with EDs. Difficulties with emotion processing and emotion regulation were strongly predictive of various aspects of eating psychopathology in both sexes. Importantly, we found that sex moderated the relationship between cognitive reappraisal and eating restraint. As such, low use of reappraisal was found to be associated with higher levels of restraint in females but not in males.

DISCUSSION

Difficulties with emotion processing and emotion regulation are associated with eating psychopathology in both males and females. Reappraisal was not found to be associated with reduced eating psychopathology in males, suggesting a cautious approach to interventions targeting this strategy. Research around explanatory mechanisms and interventions must adopt a broader viewpoint including those that are traditionally overlooked in EDs.

Sensory processing and eating behaviours in autism: A systematic review

OBJECTIVES

The aim of this study was to assess the relationship between sensory processing and a broad range of eating behaviours across the lifespan.

METHODS

Five electronic databases of published and unpublished quantitative studies were systematically searched, evaluated for risk of bias and synthesised according to identified eating outcomes.

RESULTS

Across 25 studies, there was consistent evidence of a relationship between sensory processing and a range of eating behaviours. There was early evidence for the particular role of taste/smell sensitivities, as well as hypersensitivities, although future research is needed looking at different sensory patterns and modalities. There was also tentative evidence to suggest this relationship extends across development.

DISCUSSION

Study findings are discussed in relation to implications for sensory-based eating and feeding interventions and the development of eating disorders. Methodological and conceptual limitations are discussed and suggestions for future research are made to address these limitations. A broader investigation of multi-sensory issues and clearly defined eating behaviours, including disordered eating in clinically diagnosed samples, will allow for a more comprehensive and robust understanding of the relationship between sensory processing and eating behaviours in autism.

Is Alexithymia the Link Between Anorexia and Autism Spectrum Disorders?

Objective

Alexithymia main features include deficits in empathy, emotion recognition and regulation. Alexithymia has been recently proposed as a potential key to explain the presence of the so-called 'autistic spectrum disorder' signs (ASD), in patients with Anorexia Nervosa (AN). Objective of this review is to summarize current knowledge on the potential role of alexithymia in linking ASD and AN.

Method

A systematic search has been conducted on PUBMED database of the last 10 years, in accordance with PRISMA Guidelines, applying queries in the 'PubMed Advanced Search Builder'.

Results

We initially retrieved 18 papers; the final selection has led to seven papers. According to the available studies, alexithymia is widely represented in samples of AN patients and comorbid ASD traits. However, the specific load of alexithymia in AN with ASD features is still in debate, as well as the potential role of interoceptive deficits. We have found several limitations in the reviewed studies, which shared a cross-sectional design, with no comparison between a pre and a post-treatment condition (except for one study), small samples sizes and some heterogeneity of administered instruments.

Conclusions

the specific load of alexithymia in explaining the link between AN and ASD is still in debate. Interoception deficit has been proposed as having a crucial role. Further research should be devoted to longitudinal studies and not only to cross-sectional observations.

Does local cerebellar volume predict treatment success in anorexia nervosa?

Anorexia nervosa (AN) is difficult to treat with up to half of patients failing to gain weight during treatment. Neurobiological factors predicting treatment response in AN are poorly understood. In this longitudinal study, we aimed to identify morphological characteristics in the grey matter which predict treatment success in patients with AN. Fifty patients with severe AN participated in an eating disorder-specific inpatient treatment. On admission, T1-weighted magnetic resonance images were acquired from all patients. Half of the patients successfully gained weight, reaching a body-mass index ≥ 17.5 kg/m². Using voxel-based morphometry, local grey matter volumes were compared between the two groups of patients who gained weight and those who did not. This approach allowed us to identify anatomical characteristics which predict treatment success in terms of post-treatment weight status. Patients who did not reach the weight threshold at discharge had a smaller volume in the right cerebellar crus I at the time of admission. In this group, smaller volume was associated with a greater alexithymia score. The findings suggest that a trophic state within the cerebellum before treatment might be prognostic for treatment success. Consistent with previous reports, this result further substantiates the possible role of the cerebellum in the psychopathology of AN.

Autistic Traits and Social Responsiveness: The Relationship Between Autistic Traits and Comorbid Psychiatric Symptoms in Adolescents with Anorexia Nervosa

INTRODUCTION

It is known that patients with anorexia nervosa (AN) display social difficulties like social responsiveness and high levels of autistic behaviors such as rigidity, narrow interests of food and weight; however it is not clear whether they have comorbid Autism Spectrum Disorders (ASD) or it is about acute phase of illness. In this study it is aimed to investigate autistic traits and social responsiveness in adolescents with AN.

METHODS

Study group was consisted of 39 female AN patients aged between 12-18 years. Control group was consisted of 34 female adolescents who did not have any psychiatric disorder. K-SADS-PL was applied to all participants in order to detect the psychiatric disorders. Autism traits and social responsiveness were evaluated using Social Responsiveness Scale. All adolescents of the study were administered The Eating Attitude Test, Beck Depression Inventory, Screen for Child Anxiety and Related Disorders, Maudsley Obsesive Compulsive Inventory.

RESULTS

Results of the study indicated that adolescents with AN had higher symptoms of depression, anxiety and autism-like symptom clusters; and lower social responsiveness. Psychiatric comorbidities were not associated with these difficulties.

CONCLUSION

The results show that AN patients have an impairment of social responsiveness, the impairment seems to be associated with AN regardless of psychiatric comorbidities. Despite these two disorders are considered unrelated, they have several traits in common. These results suggest that there may be a common pathogenesis between ASD and AN.

Adolescents With Autism Spectrum Disorder and Anorexia Nervosa Comorbidity: Common Features and Treatment Possibilities With Cognitive Remediation Therapy and Oxytocin

Autistic traits or autism spectrum disorder (ASD) can be found in 4% to 52% of anorexic patients, which makes the treatment of these patients very challenging. In this review, possible ways to treat ASD and anorexia nervosa (AN) comorbidity in children and adolescents are summarized. Over recent years, the focus has shifted from searching for the evidence of connections between these two disorders, which have started with Gillberg's study in 1983, to searching for more effective and holistic treatment of this comorbidity. The latter is known to contribute to more severe courses and worse prognosis, which is probably related to the obstacles in both diagnosing and treating. Since AN usually starts in early adolescence and high-functioning ASD children seem to begin struggling with increased pressure in adolescence, while various comorbidities can occur, it is important to improve the treatment of this comorbidity in young patients and to tailor it specifically in terms of diagnosing. In this paper, a literature review is conducted on common features and promising treatment possibilities. We describe cognitive remediation therapy and the promising pharmacotherapeutic candidate oxytocin with a special focus on adolescents.

The Relationship between Autism and Ehlers-Danlos Syndromes/Hypermobility Spectrum Disorders

Considerable interest has arisen concerning the relationship between hereditary connective tissue disorders such as the Ehlers-Danlos syndromes (EDS)/hypermobility spectrum disorders (HSD) and autism, both in terms of their comorbidity as well as co-occurrence within the same families. This paper reviews our current state of knowledge, as well as highlighting unanswered questions concerning this remarkable patient group, which we hope will attract further scientific interest in coming years. In particular, patients themselves are demanding more research into this growing area of interest, although science has been slow to answer that call. Here, we address the overlap between these two spectrum conditions, including neurobehavioral, psychiatric, and neurological commonalities, shared peripheral neuropathies and neuropathologies, and similar autonomic and immune dysregulation. Together, these data highlight the potential relatedness of these two conditions and suggest that EDS/HSD may represent a subtype of autism.