Characteristics of autism spectrum disorders are associated with longer duration of anorexia nervosa: A systematic review and meta-analysis

Exploring neurocognitive features in adolescents and young adults with anorexia nervosa: Evidence from a longitudinal study

OBJECTIVE

We aimed to evaluate longitudinal changes in set-shifting and central coherence in a predominantly adolescent cohort with anorexia nervosa (AN) and to explore whether these factors predict long-term eating disorder outcomes.

METHOD

Ninety-two female patients with AN (mean age: 16.2, range: 13-21 years) completed neurocognitive tests (Rey Complex Figure Test, Adapted Version of the Wisconsin Card Sorting Test) before and after 12 months of psychotherapeutic treatment (n = 45 Maudsley AN Treatment, MANTRa; n = 47 standard psychotherapy; groups not randomised). Eating disorder severity was assessed at baseline, after 6, 12 and 18 months.

RESULTS

Central coherence (indicated by an increase in the Rey Figure Style Index) and set-shifting (indicated by a reduction in the percentage of perseverative errors) significantly improved over the course of treatment, with similar outcomes across groups. Lower central coherence was associated with higher eating disorder severity. Individuals with lower baseline set-shifting ability tended to have worse eating disorder outcomes in the long-term. However, this trend did not reach statistical significance in a multilevel linear mixed model.

CONCLUSIONS

Neurocognitive difficulties in adolescents and young adults with AN can improve after treatment. Interventions specifically addressing flexibility in thinking and behaviour may contribute to treatment success.

The Cognitive Profile in Adolescents With Anorexia Nervosa and the Relationship With Autism and ADHD: A Pilot Study

OBJECTIVE

We aimed to examine the cognitive profile in adolescents with anorexia nervosa (AN) and its association with traits of autism spectrum disorder (ASD) and ADHD. In addition, resemblance in the cognitive profile between youths with AN and their parents was explored.

METHODS

Adolescent females with acute AN (n = 20) and a healthy comparison group (n = 28) completed neuropsychological tasks of set-shifting (Trail making test, Wisconsin Card Sorting Test) and central coherence (Rey Complex Figures Task, Group Embedded Figures Test, object assembly subtest). In the AN group, mothers and fathers (n = 31) also completed the neuropsychological tasks. Traits of ASD and ADHD were assessed. The AN group was reassessed after weight gain.

RESULTS

Weight-restored AN adolescents scored higher on the Group Embedded Figures Test than a comparison group (p < 0.001). No other set-shifting and central coherence differences were found across groups. A father-child correlation emerged in the object assembly subtest (r = 0.53, p = 0.035). ASD and ADHD traits were common in the AN group and not only related to starvation. No associations were found between neuropsychological deficits and traits of ASD and ADHD.

CONCLUSIONS

Scant support was found for weaker central coherence in weight-recovered adolescents with AN. Set-shifting impairments could not be observed in young females with acute AN or after weight recovery.

Autism spectrum disorder and anorexia nervosa: Investigating the behavioural and neurocognitive overlap

Autism spectrum disorder (autism) and anorexia nervosa (AN) share many clinical features. Two key neurocognitive correlates of the autistic dyad, specifically, mentalising (social impairment) and set-shifting (restricted and repetitive behaviours/interests [RRBI]) were investigated in a sample of 327 adult participants with autism (n = 100; 50 females, 50 male), AN (n = 82; 54 females, 28 male), autism and AN (n = 45; 36 females, 9 male), and 100 (50 female, 50 male) control participants from the general population. A battery of self-report (Autism Spectrum Quotient, Eating Disorder Examination Questionnaire, Reflective Function Questionnaire, and Repetitive Behaviour Questionnaire 2 - Adult version) and performance-based (Wisconsin Card Sort Task [WCST] and Penn Emotion Recognition Test [ER-40]) measures were administered online. Clinical participants reported greater mentalising difficulty, more repetitive behaviour, and displayed worse mentalising ability compared to controls, with no difference between the clinical groups. Eating disorder psychopathology predicted error (total and perseverative) rates on the WCST, while lower levels of autistic traits were positively associated with ER-40 accuracy. We provide evidence that clinical features of autism and AN might have specific neurocognitive relevance. Improved understanding of the mechanisms underlying the overlapping features of autism and AN can have critical implications for early detection and improved and tailored intervention.

A Mixed Method Systematic Review Into the Impact of ED Treatment in Autistic People and Those With High Autistic Traits

OBJECTIVE

Our understanding of the impact of eating disorders (ED) treatment in Autistic people remains elusive. Research has begun to explore ED treatment outcomes and experiences in this population, however current understandings are poorly integrated. The current review therefore sought to explore the impact of ED treatment on Autistic people and those with higher Autistic traits.

METHOD

A convergent, segregated approach was used, independently evaluating quantitative then qualitative studies before integrating findings into a coherent narrative synthesis.

RESULTS

Autistic people and people with higher Autistic traits report poorer experiences of treatment and may be at increased risk of inpatient admission and prolonged inpatient treatment, possibly explained by difficulties with treatment timeframes and a lack of autism-informed support. Both groups reported similar improvements in ED symptoms and BMI. Higher rates of psychosocial difficulties pre-and post-treatment were reported in those with higher Autistic traits, and emotion-focused interventions were felt to be particularly relevant to Autistic presentations of EDs. Concerns were reported as to how well aligned group-based programs and cognitive-based interventions are for Autistic individuals and those reporting higher Autistic traits.

DISCUSSION

Future research in diagnosed autism samples is urgently needed to develop a more robust understanding of Autistic outcomes and experiences. Review findings demonstrate the need for increased understanding of ED presentations and the possible need for treatment adaptations, for Autistic people or those with higher Autistic traits.

Enhancing emotional abilities in anorexia nervosa treatment: A rolling-group cognitive remediation and emotional skills training protocol

INTRODUCTION

Anorexia nervosa (AN) is characterised by limited remission rates and emotional dimensions are often neglected. Cognitive remediation and emotional skills training (CREST) protocol aims to address cognitive and emotional factors. This study evaluates the feasibility and effectiveness of a modified rolling-group CREST protocol in an inpatient setting.

METHODS

Quasi-experimental design evaluated CREST protocol in a rehabilitation programme. A total of 116 females diagnosed with AN were included, of whom 63 were included in the CREST protocol and 53 in the standard rehabilitation treatment. Various standardized measures were employed to assess psychopathology. Data collection occurred longitudinally, before and after CREST implementation.

RESULTS

No significant differences emerged between groups regarding changes in specific eating psychopathology. CREST group exhibited significant improvements in emotion regulation (p = 0.002) and social skills (p = 0.014), besides a reduction in alexithymia (p < 0.001) and cognitive rigidity (p = 0.013). Empathic features remained stable. Participants reported positive perceptions of the CREST intervention.

DISCUSSION

The study highlights the potential benefits of integrating emotional training within multidisciplinary intensive treatment for AN. Results emphasise the importance of treatment protocol with more affective and hot-cognition-related interventions, beyond weight-related psychopathology. Implementing a rolling-group CREST protocol in an inpatient setting showed promise in enhancing the emotional abilities of AN patients.

Social communication and restricted, repetitive behavior as assessed with a diagnostic tool for autism (ADOS-2) in women with anorexia nervosa

OBJECTIVE

In anorexia nervosa (AN), the traits of autism spectrum disorder (ASD) are associated with poor outcomes. However, the subtle nature of these characteristics remains poorly understood. We investigated the in-depth patterns of ASD traits using Autism Diagnostic Observation Schedule-Second Edition (ADOS-2) in women with AN.

METHODS

Of 28 women with ICD-10 AN, 16 (age 19-30 years) participated in the ADOS-2, a video-recorded, semistructured diagnostic assessment for social communication and interaction and restricted, repetitive behaviors and interests related to ASD. None of the participants had previously been diagnosed with ASD. Other measurements included the Eating Disorder Examination Questionnaire and the Wechsler Abbreviated Scale of Intelligence-IV.

RESULTS

Five individuals (18% of all, 31% of those assessed) scored above the cutoff for autism in ADOS-2. They had challenges in social communication and interaction, manifesting as sustained difficulties in social relationships and deficits in conversation skills. Few described being frequently misunderstood by others, including in the eating disorder treatment settings. Three individuals showed prominent restricted and repetitive behaviors such as ritual seeking, eating-related routines, sensory sensitivity related to food texture and selective eating, and intense interest in specific topics. The mean duration of AN in women above the cutoff was twice as long compared with those below (12.3 vs. 6.2 years).

DISCUSSION

The ASD-related characteristics and behavior appear to contribute to the manifestation and duration of AN in a subgroup of women. Among these women, the traits of ASD appear to be mixed with eating disorder symptoms, which should be taken into account in the treatment.

The clinical characteristics of autistic women with restrictive eating disorders

BACKGROUND

Autistic women are at high risk of developing restrictive eating disorders (REDs), such as anorexia nervosa.

AIMS

This study provides an overview of the clinical characteristics of autistic women with REDs to (i) enhance understanding of increased risk, and (ii) support the identification of autistic women in eating disorder services.

METHOD

We compared self-reported autistic and disordered eating characteristics of: autistic participants with REDs (Autism + REDs; n = 57); autistic participants without REDs (Autism; n = 69); and women with REDs who are not autistic (REDs; n = 80). We also included a group of women with high autistic traits (HATs) and REDs, but no formal autism diagnosis (HATs + REDs; n = 38).

RESULTS

Autism + REDs participants scored similarly to Autism participants in terms of autistic characteristics and to REDs participants in terms of experiencing traditional disordered eating symptoms. Autism + REDs participants were distinguished from both groups by having more restricted and repetitive behaviours and autism-specific eating behaviours related to sensory processing, flexibility and social differences. HATs + REDs participants showed a similar pattern of scores to Autism + REDs participants, and both also presented with high levels of co-occurring mental health difficulties, particularly social anxiety.

CONCLUSION

The presentation of autistic women with REDs is complex, including both traditional disordered eating symptoms and autism-related needs, as well as high levels of co-occurring mental health difficulties. In eating disorder services, the REDs presentation of autistic women and those with HATs should be formulated with reference to autism-specific eating behaviours and co-occurring difficulties. Treatment adaptations should be offered to accommodate autistic characteristics and related needs.

No Evidence for Cross-Sectional or Longitudinal Associations between Cognitive Flexibility Performances and Nutritional Status in a Cohort of Inpatients with Anorexia Nervosa

BACKGROUND

According to the Cognitive-Interpersonal model of anorexia nervosa (AN), the combined influence of cognitive and socio-emotional difficulties would constitute vulnerability and maintaining factors. Poor cognitive flexibility is one of the endophenotypic candidates (i.e., a trait marker) of the disorder, but few studies have examined its association with illness symptom variations, notably weight status. The study aimed to evaluate the relationships between cognitive flexibility performances and nutritional status indices (BMI; body composition) at different times of the disorder.

METHODS

Cross-sectional and longitudinal associations between cognitive flexibility (TAP 2.1) and nutritional status indices, along with anxious and depressive (HAD) and eating disorder (EDE-Q) symptomatology were investigated using univariate and multivariate analyses in a cohort of AN inpatients evaluated at hospital admission (N = 167) and discharge (N = 94).

RESULTS

We found no or negligible associations between nutritional status and HAD or EDE-Q scores or cognitive flexibility performances, either cross-sectionally or longitudinally. Cognitive performances did not significantly differ between the AN subtypes.

CONCLUSIONS

In agreement with the Cognitive-Interpersonal model of AN, cognitive flexibility is independent of nutritional status, as well as the AN subtype. It is also independent of the levels of anxious, depressive, or ED symptomatology. A new therapeutic approach targeting cognitive flexibility and intolerance to change could benefit severely emaciated people with AN, regardless of disease subtype and level of dysphoria.

Overlap of eating disorders and neurodivergence: the role of inhibitory control

BACKGROUND

Difficulties with inhibitory control have been identified in eating disorders (EDs) and neurodevelopmental disorders (NDs; including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder), and there appear to be parallels between the expression of these impairments. It is theorised that impairments in inhibitory control within NDs may represent a unique vulnerability for eating disorders (EDs), and this same mechanism may contribute to poorer treatment outcomes. This review seeks to determine the state of the literature concerning the role of inhibitory control in the overlap of EDs and neurodivergence.

METHOD

A scoping review was conducted to summarise extant research, and to identify gaps in the existing knowledge base. Scopus, Medline, PsycInfo, Embase, and ProQuest were systematically searched. Studies were included if the study measured traits of ADHD or autism, and symptoms of ED, and required participants to complete a performance task measure of inhibitory control. Where studies included a cohort with both an ND and ED, these results had to be reported separately from cohorts with a singular diagnosis. Studies were required to be published in English, within the last 10 years.

RESULTS

No studies explored the relationship between autism and EDs using behavioural measures of inhibitory control. Four studies exploring the relationship between ADHD and EDs using behavioural measures of inhibitory control met selection criteria. These studies showed a multifaceted relationship between these conditions, with differences emerging between domains of inhibitory control. ADHD symptoms predicted poorer performance on measures of response inhibition in a non-clinical sample; this was not replicated in clinical samples, nor was there a significant association with EDs. Both ADHD and ED symptoms are associated with poor performance on attentional control measures; where these diagnoses were combined, performance was worse than for those with a singular diagnosis of ADHD. This was not replicated when compared to those with only ED diagnoses.

CONCLUSION

Impairments in attentional control may represent a unique vulnerability for the development of an ED and contribute to poor treatment outcomes. Further research is needed to explore the role of inhibitory control in EDs, ADHD and autism, including the use of both self-report and behavioural measures to capture the domains of inhibitory control.

A longitudinal study of autism spectrum disorder characteristics in adolescents with restrictive type anorexia nervosa during and after underweight

OBJECTIVES

This prospective, longitudinal study aims to compare the prevalence of autism spectrum disorder (ASD) characteristics in adolescents with anorexia nervosa (AN) during and after underweight in order to help unravel the complex link between both conditions.

METHODS

24 adolescents with AN completed the youth self-report, autism spectrum quotient (AQ) or autism spectrum quotient adolescent version (AQ - adolescent) and a questionnaire designed by the researchers during a state of underweight and after weight recovery.

RESULTS

AQ total score and several AQ subscale scores at the time of underweight are significantly higher than after weight recovery with medium to large effect sizes. Linear modelling cannot prove a significant effect of weight gain, internalizing problems or medication use on AQ score, but it does show an association between AQ during underweight and AQ after weight recovery.

CONCLUSIONS

The results highlight the complexity of the link between AN and ASD characteristics. Although a clear change in AQ score is seen in part of the participants, this effect cannot be generalized and a link with weight change cannot be demonstrated. It seems likely that ASD characteristics in AN are a combination of trait and state: underweight and starvation might exacerbate potentially present traits. Part of our results may indicate the existence of subgroups based on AQ score during underweight. Our study supports the theory that more ASD characteristics at T1 may result in a poorer outcome and a higher need for specified and intensive treatment.

Psychologically informed care of patients with anorexia nervosa on an acute medical ward

Anorexia nervosa is a challenging and highly distressing illness associated with significant and often debilitating symptoms that affect the person's physical and mental well-being, as well as their wider social networks. Although some patients can make important steps in their recovery in the community, many will become significantly unwell and require medical stabilisation and refeeding in an acute medical ward as a result of significant weight loss. This article describes some of the challenges experienced by adult nurses when caring for patients with anorexia nervosa on acute medical wards and explores how the patient's distress may manifest and complicate the recovery process. The article also discusses the principles of psychologically informed care and therapeutic interactions that nurses can use to promote recovery and ensure optimal practice.

Exploring the intersection of autism spectrum disorder and eating disorders: understanding the unique challenges and treatment considerations for autistic women with eating disorders

PURPOSE OF REVIEW

Autistic women struggle with high levels of both autistic eating behaviours and disordered eating behaviours , which might make them particularly vulnerable to develop eating disorders. Research investigating the presence and characteristics of eating disorders in autistic women is however limited, as is research examining the role of autism in the treatment and recovery of an eating disorder in autistic women.

RECENT FINDINGS

The link between autism and eating disorders has mainly been investigated from the field of eating disorder research, with studies finding an overrepresentation of autism or autistic traits in eating disorders populations. Findings also suggest that autism or autistic traits are associated with a more serious presentation of the eating disorders, including a higher chance of a chronic course of the eating disorders. Most studies however lack comprehensive autism assessments, making it difficult to determine the actual prevalence of autism and its role in women with eating disorders.

SUMMARY

Autistic women with an eating disorder seem to suffer from more complex eating disorders and seem to not benefit from current treatment modalities. This could be partly related to specific autism characteristics such as sensory sensitivities, which are not being considered by current treatment protocols. Future research needs to shed light on what underlies the eating behaviours of autistic women with an eating disorder, in order to help to adapt current treatment modalities to meet the unique needs of these women.

Dysfunctional decision-making in binge-eating disorder: A meta-analysis and systematic review

Binge-Eating Disorder (BED) involves anticipatory craving and urges, subjective loss-of-control during binge-eating episodes, and post-feeding psychological distress and guilt. Evidence indicates neurocognitive dysfunctions contribute to BED onset, maintenance, and treatment response. However, an integrated understanding of how cognitive processes underpin BED symptomology is lacking. We utilised a multi-stage decision-making model defining ten cognitive processes underpinning Preference Formation, Choice Implementation, Feedback Processing, and Flexibility/Shifting, to comprehensively review research published since 2013. We used preregistered PICOS criteria to assess 1966 articles identified from PubMed, PsycInfo, and Scopus database searches. This yielded 50 studies reporting behavioural cognitive tasks outcomes, comparing individuals with BED to controls with normal and higher weight. Meta-analyses revealed a unique profile of cognitive dysfunctions that spanned all decision-making stages. Significant deficits were evident in Uncertainty Evaluation, Attentional Inhibition, Choice Consistency, and Cognitive Flexibility/Set-shifting. We propose a novel model of dysfunctional decision-making processes in BED and describe their role in binge-eating behaviour. We further highlight the potential for cognitive interventions to target these processes and address the significant treatment gap in BED.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

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.

"Work WITH us": a Delphi study about improving eating disorder treatment for autistic women with anorexia nervosa

BACKGROUND

There is an increased prevalence of anorexia nervosa (AN) in autistic women and this group has poorer treatment outcomes compared to non-autistic women with AN. However, there is little research into improving eating disorder treatment for autistic women. This study investigated how best to support autistic women with AN within eating disorder services.

METHOD

A three-stage Delphi study was conducted with 49 participants with relevant expertise as a researcher, clinician, or expert by experience.

RESULTS

A total of 70 statements were generated, with 56 reaching consensus after the final round. Statements reaching consensus made recommendations for adaptations to treatment, staff training, and service organisation.

CONCLUSIONS

The results highlight the need to distinguish between autism- and AN-related difficulties, accommodate autistic traits such as sensory sensitivities and communication differences, and ensure the autistic voice is present in both the development and delivery of care. Future research should investigate the impact of these adaptations on outcomes. The applicability of these recommendations to autistic people with other eating disorders and of other genders needs to be investigated further.

Emotion recognition, alexithymia, empathy, and emotion regulation in women with anorexia nervosa

PURPOSE

Anorexia nervosa (AN) is associated with challenges in recognizing, understanding, and interpreting one's own and other's emotional states, feelings, and thoughts. It is unknown whether difficulties in emotion processing occur independently of common comorbid symptoms of AN and predict acute eating disorder characteristics. We aimed to examine emotion recognition, alexithymia, emotion regulation, and empathy in individuals with AN and to assess whether these predict eating disorder symptoms independently from comorbid symptoms.

METHODS

Participants included 42 women with AN and 40 healthy control (HC) women between 18-30 years. Basic and complex emotion recognition was assessed with face photos and video clips. Alexithymia, empathy, emotion regulation, and comorbid symptoms (anxiety, depressive, and obsessive-compulsive symptoms and ASD traits) were assessed with self-assessment questionnaires.

RESULTS

Participants with AN exhibited difficulties in basic and complex emotion recognition, as well as increased alexithymia, decreased empathy, and challenges in emotion regulation when compared to HCs. After controlling for comorbid symptoms, differences remained only in complex emotion recognition. Challenges in emotion recognition were associated with lower body mass index, and increased alexithymia was associated with increased eating disorder symptoms. Increased challenges in emotion regulation were associated with a shorter duration of illness, higher body mass index, and increased eating disorder symptoms.

CONCLUSIONS

Participants with AN displayed widespread deficit in emotion processing, but only challenges in complex emotion recognition occurred independently from comorbid symptoms. Deficits in emotion processing may contribute to the illness severity and thus could be an important treatment target.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Affective cognition in eating disorders: a systematic review and meta-analysis of the performance on the "Reading the Mind in the Eyes" Test

BACKGROUND

The Reading the Mind in the Eyes Test (RMET) is listed in the National Institute of Mental Health's Research Domain Criteria as a tool apt to measure the understanding of others' mental states. People diagnosed with anorexia nervosa (AN) showed poorer performances on the RMET than healthy controls. Less data are available concerning other eating disorders.

METHODS

Systematic review of four major databases from inception to July 15, 2021 following the PRISMA guidelines. Meta-analysis of cross-sectional observational studies comparing the scores of the RMET between patients with eating disorders and age- and-gender matched control groups.

RESULTS

Out of 21 studies, we retrieved 29 independent samples of patients diagnosed with an eating disorder. Patients with active AN (n = 580) showed worse performances on the RMET than controls (n = 1019). Year of publication accounted for 61% of the (substantial: I2 = 81%) heterogeneity in the meta-analysis. Earlier studies were more likely to find worse performances on the RMET of patients with active AN than later studies. Patients with bulimia nervosa (n = 185) performed poorly as compared to controls (n = 249), but the results were not statistically significant on the random-effect model. Obese patients with binge-eating disorder (n = 54) did not differ on the RMET from obese controls (n = 52). Patients with eating disorder not otherwise specified (n = 57) showed minimal differences compared to controls (n = 96). Study quality was good in six studies only.

CONCLUSIONS

Patients with eating disorders do not suffer from an impaired understanding of others' mental states, except for a still-to-be-identified subgroup of patients with active AN.

LEVEL OF EVIDENCE

I, systematic review and meta-analysis.

Autistic characteristics in youth with anorexia nervosa before and after treatment

OBJECTIVE

Cognitive characteristics common to autistic individuals are often seen in adults with anorexia nervosa (AN), raising the question of whether autistic people and people with AN may share an endophenotype. We need to examine autistic characteristics during the early stages of AN to accurately parse true symptom co-occurrence from behavioural alterations due to prolonged illness.

METHODS

We conducted a post-hoc analysis examining autistic characteristics in 59 youth with AN. Adolescents and parents participating in a randomised-clinical trial for AN completed questionnaires probing autistic characteristics at baseline and treatment end. We categorised participants as above or below cut-offs of clinical indicators of autism using the Autism Probability Index (API) and the Autism Spectrum Quotient-10.

RESULTS

Rates of high autistic characteristics ranged between 0% and 36% depending on the instrument used and how the data was obtained (i.e., by informant report or self-report). Paternal report of autistic characteristics differed across treatment completers versus non completers and maternal report indicated lower weight gain for those with elevated characteristics.

CONCLUSIONS

Low rates of autism and fluctuations in autistic features during treatment underscore the importance of longitudinal examinations of autistic characteristics in adolescents with AN. Future studies need to replicate findings in a larger adolescent sample.

TRIAL REGISTRATION

ClinicalTrails.gov Identifier NCT03928028.

Experiences of mimicry in eating disorders

BACKGROUND

People unknowingly mimic the behaviors of others, a process that results in feelings of affiliation. However, some individuals with eating disorders describe feeling "triggered" when mimicked. This study explores the effects of implicit non-verbal mimicry on individuals with a history of an eating disorder (ED-His) compared to healthy controls (HCs).

METHOD

Women (N = 118, n_ED-His = 31; M_age = 21 years) participated in a laboratory task with a confederate trained to either discreetly mimic (Mimicry condition) or not mimic (No-Mimicry condition) the mannerisms of the participant. Participants rated the likability of the confederate and the smoothness of the interaction.

RESULTS

Participants in the No-Mimicry condition rated the confederate as significantly more likable than in the Mimicry condition, and ED-His rated the confederate as more likable than HCs. ED-His in the Mimicry condition rated the interaction as less smooth than HCs, whereas this pattern was not found in the No-Mimicry condition. Among ED-His, longer disorder duration (≥ 3.87 years) was associated with less liking of a confederate who mimicked and more liking of a confederate who did not mimic.

CONCLUSIONS

We discuss the implications of these findings for interpersonal therapeutic processes and group treatment settings for eating disorders. Our study on subtle, nonverbal mimicry revealed differences in social behavior for women with a history of an eating disorder compared to healthy women. For participants with an eating disorder history, a longer duration of illness was associated with a worse pattern of affiliation, reflected in lower liking of a mimicker. Further research on how diverging processes of affiliation may function to perpetuate the chronicity of eating disorders and implications for treatment is needed.

A comparison of the eating disorder service experiences of autistic and non-autistic women in the UK

Objective

Qualitative studies report that autistic women have poor experiences when being treated for an eating disorder (ED) and express that ED services are not appropriately tailored to meet their needs. It is unclear whether their experience differs to other women accessing ED services. The aim of the current study was to compare autistic and non‐autistic women's ED illness history and experiences in ED services.

Method

An online survey about ED illness history and their experience with ED treatment was completed by 46 autistic women with a restrictive ED and 110 non‐autistic women with a restrictive ED.

Results

Despite some similarities, there were three key differences in the experiences reported by autistic and non‐autistic women. First, autistic women reported a longer duration of ED and being diagnosed with an ED at a younger age than non‐autistic women. Second, autistic women reported accessing a broader range of healthcare settings and ED treatments than non‐autistic women when being treated for an ED. Finally, autistic women rated their experiences of inpatient care, dietetic input, and cognitive behavioural therapy (CBT) as significantly less beneficial than non‐autistic women when being treated for an ED.

Conclusion

These findings increase understanding of autistic women's ED experience and can help to shape ED services and treatments to better accommodate the needs of their autistic clients.

The current study is the first to compare the eating disorder (ED) illness history and treatment experiences of autistic and non‐autistic women.

Autistic women with EDs are diagnosed at a younger age and report longer illness duration than non‐autistic women.

Autistic women with EDs tend to access a broader range of healthcare settings and ED treatments than non‐autistic women, but report these to be less beneficial.

Cognitive Behavioral and Cognitive Remediation Strategies for Managing Co-Occurring Anorexia Nervosa and Elevated Autism Spectrum Traits

Anorexia nervosa (AN) is a potentially severe eating disorder whose core characteristics include energy intake restriction leading to low body weight. Autism spectrum disorder (ASD) is a developmental disorder characterized by deficits in social interaction and communication as well as repetitive, stereotyped behavior and interests. Both high ASD traits and diagnosed ASD are overrepresented among individuals with AN, and AN and ASD appear to share certain neurocognitive features. These features are associated with the severity of eating disorder symptoms and prolongation of AN. Thus, individuals with AN and high ASD traits or ASD may benefit less from traditional treatment when compared to those with low ASD traits. No previous reviews have summarized what is known about treatment adaptations for individuals with AN and high ASD traits or ASD. The purpose of this narrative review was to investigate the feasibility of cognitive remediation therapy (CRT), cognitive remediation and emotional skill training (CREST), and cognitive behavioral therapy (CBT), and give an overview of treatment modifications for individuals with AN and co-occurring ASD or high ASD traits. We found nine studies that fulfilled our inclusion criteria. The combined results suggest that individuals with AN and high ASD traits or ASD benefit less from CRT, CREST, and CBT than those with AN and low ASD traits. However, CRT and CREST administered in individual format may be associated with improved cognitive flexibility, motivation for change, and decreased alexithymia among adults with AN and high ASD traits or ASD. Individuals with comorbid AN and ASD themselves highlight the importance of treatment adaptations that take the characteristics of ASD into account. In the future, controlled studies of the treatment strategies for individuals with AN and ASD/high ASD traits are needed in order to improve the outcome of individuals with this challenging comorbidity.

Cognitive flexibility and attention to detail in adolescents and adults with severe forms of anorexia nervosa

OBJECTIVE

To determine if adolescents and adults diagnosed with anorexia nervosa differ in their levels of cognitive flexibility and attention to detail independently of potential confounds.

METHOD

Sixty-two adolescents and 54 adults were assessed while receiving inpatient treatment and completed the following self-reports: Eating Disorders Examination Questionnaire, Maudsley Obsessive Compulsive Inventory and Hospital Anxiety and Depression scale. Performance-based evaluations included the Wisconsin Card Sorting Test Computerised Version, the Comprehensive Trail Making Test, the Brixton Spatial Anticipation Test, the Rey Complex Figure and the Group Embedded Figures Test.

RESULTS

Comparisons of the adolescents and adults with anorexia nervosa revealed no significant differences for any of the neuropsychological test scores even after adjusting for potential confounding factors. Neither cognitive flexibility nor attention to detail were associated with level of eating disorder symptomatology, depression, anxiety or obsessive-compulsive symptomatology. Unlike age, illness duration was found weakly associated with perseverative errors Wisconsin Card Sorting Test and with the central coherence index of the Rey Complex Figure recall condition.

CONCLUSIONS

Set-shifting and central coherence performance were independent of age, clinical symptoms severity and emotional status. Additional studies on the relationship between the duration of anorexia nervosa and neuropsychological difficulties are needed.

The obsessive-compulsive spectrum: A network analysis

Several studies have shown that obsessive-compulsive disorder (OCD), eating disorders (ED), autism spectrum disorders (ASD) and body dysmorphic disorder (BDD) share obsessive-compulsive (OC) symptoms and often co-occur, which could be seen as indicative of a common etiological basis. In addition, they also appear to have similarities in executive functioning. The present study investigated disorder-specific symptoms and executive functioning as a possible joint factor in individuals with OCD (n=53), BDD (n=95), ED (n=171) and ASD (n=73), and in healthy controls (n=110). The participants completed online questionnaires measuring OCD, ED, ASD and BDD related symptoms as well as executive functioning. The clinical groups were first compared to the healthy controls. Subsequently, a network analysis was performed only with the OC-groups. This network approach assumes that psychopathological disorders are the result of causal symptom interactions. As expected, the healthy controls reported less severe symptoms compared to the OC patient groups. The network analysis suggested that the executive functioning skill set shifting/attention switching and the ASD symptoms, social and communication skills were the most central nodes in the model. Difficulty with cognitive flexibility and social factors are central in OC-spectrum disorders and may be perpetuating factors and thus a relevant focus of treatment.

Atypical Sensory Processing Is Associated With Lower Body Mass Index and Increased Eating Disturbance in Individuals With Anorexia Nervosa

BACKGROUND

Elevated autism spectrum disorder (ASD) traits are associated with anorexia nervosa (AN). Conversely, eating disturbances, which are core characteristics of AN, are common in ASD. Among individuals with ASD, atypical sensory processing is associated with eating disturbance. Because AN and ASD appear to overlap, it would be crucial to understand whether sensory processing atypicality exist also in AN. Further, it would be essential to find if atypical sensory processing is associated with eating disturbances in individuals with AN, since treatment modifications may be needed. We therefore aimed to examine whether atypical sensory processing is associated with AN and its core characteristics.

METHODS

Participants of the current study included 42 individuals with AN and 40 healthy controls (HCs). All participants were adult women. Sensory processing, other ASD traits, and eating disorder symptoms were assessed with self-report questionnaires.

RESULTS

Individuals with AN reported lower registration, decreased sensation seeking, increased sensory sensitivity, and increased sensation avoiding compared to HCs. When analyzing groups with restrictive AN (AN-R) and binge-purge type AN (AN-BP) separately, only individuals with AN-R exhibited decreased sensation seeking, and only those with AN-BP exhibited lower registration. After controlling for body mass index as a covariate, group differences remained significant only in sensory sensitivity between individuals with AN and HCs. Increased atypical sensory processing predicted lower body mass index and increased disordered eating.

CONCLUSION

Results suggest that sensory processing appears to differ between AN and HC women, and AN subtypes may exhibit distinct sensory processing atypicality. Sensory sensitivity may be stable traits whereas other aspects of atypical sensory processing may be related to acute AN. Atypical sensory processing may contribute to the severity of AN, and thus it is crucial to recognize sensory processing differences when treating individuals with AN.

Autism and anorexia nervosa: Longitudinal prediction of eating disorder outcomes

BACKGROUND

Recently, elevated levels of autistic features and autism diagnoses have been reported among people with anorexia nervosa (AN). In clinical settings high levels of autistic features have been linked to more complex, highly comorbid illness presentation and poorer treatment outcome. This study aimed to examine whether autistic features predict AN symptom profile in long term.

METHODS

Altogether 118 women with lived experience of AN completed two autism assessments at time 1, the Autism Diagnostic Observation Schedule (ADOS) and the short version of the Autism Quotient (AQ10). Measures assessing AN symptom profile, including eating disorders symptoms, anxiety, depression, OCD symptoms, and Body Mass Index (BMI), were also recorded. The symptom profile measures were administered again 6 months and 2 years later. We conducted two analyses to examine the extent to which the ADOS and AQ10 scores predicted broad AN symptom profile at each three time points.

RESULTS

Overall, high levels of autistic features were consistently associated with worse psychological symptoms, but not BMI, across all time points. Both the analysis using baseline ADOS scores and self-reported AQ10 scores showed similar pattern.

CONCLUSION

The present findings consolidate previously reported associations between autistic features and worse psychological outcome among people with AN. The findings also suggest that self-report measures may be sufficient for assessing the impact of autistic features on illness outcome among people with AN. Importantly, the study highlights the need for development and further investigation of neurodiversity accommodations in the treatment of AN.

Widening the reach of family-based interventions for Anorexia Nervosa: autism-adaptations for children and adolescents

Family-based interventions are widely recommended as a first line treatment for children and young people with Anorexia Nervosa. There is clear evidence that model-adherent delivery of specific eating disorder focused family interventions has the potential to help adolescents with Anorexia Nervosa, who have typically engaged in extreme dietary restriction and lost a significant amount of weight over a relatively short period of time. Nevertheless, there remains a significant number of young people with restrictive eating disorders for whom family-based interventions for Anorexia Nervosa prove less effective, suggesting adaptations may be indicated for some. In this paper we provide a rationale and structure for considering a number of possible adaptations to the delivery of family-based therapy for anorexia nervosa specifically intended to enhance its relevance and potential effectiveness for children and adolescents on the autism spectrum; a subgroup known to represent a significant minority in eating disorder populations who have been identified as having relatively poor outcomes. Past research has shown that certain family-based treatments are effective for many children and adolescents who develop Anorexia Nervosa. At the same time this type of treatment approach in its current form does not work for everyone. Recent research has highlighted the overlap between anorexia and autism and the need for the development of adaptations to existing treatments to better meet the requirements of people on the autism spectrum who develop anorexia. With this in mind we propose a number of autism-related adaptations that could be made to family-based treatments for anorexia. We hope that these might be formally tested in the future to see if these adaptations improve outcomes for this group of individuals.

Autistic characteristics in eating disorders: Treatment adaptations and impact on clinical outcomes

OBJECTIVE

Autistic people with eating disorders (EDs) may have special needs that are not met in standard ED treatment, raising the need for treatment adaptations to accommodate co-existing autism spectrum condition (ASC). Little is currently known about the nature of existing treatment options or adaptations for this population. We conducted a pre-registered systematic review to: (1) identify research articles describing existing interventions for patients with ED and comorbid ASC, and to critically review evidence of their clinical effectiveness and cost-effectiveness (Review 1); (2) review the impact of ASC comorbidity on ED clinical outcomes (Review 2).

METHOD

Peer-reviewed studies published until the end of December 2020 were identified through a systematic search of the electronic databases: Medline, Embase, PsycINFO, Web of Science, CINAHL, Scopus and Cochrane Library.

RESULTS

Only one clinical pathway of treatment adaptations (the 'PEACE' pathway) was identified in Review 1 with early evidence of cost-savings and favourable treatment outcomes. ASC characteristics were shown in Review 2 to have no direct impact on physical outcomes or ED symptoms, but could be associated with higher rates of comorbidities and greater use of intensive ED treatment. Additionally, patients with ASC characteristics may benefit more from individual sessions, rather than group sessions.

CONCLUSIONS

Any new treatments or treatment adaptations may not directly impact on ED symptoms, but may be better able to support the complex needs of the ASC population, thus reducing subsequent need for intensive treatment. Future research is warranted to explore evidence of clinical and cost-effectiveness of interventions for this population.

Anorexia nervosa and comorbid autism spectrum disorders

PURPOSE OF REVIEW

Traits of autism spectrum disorder (ASD) are overrepresented among individuals with anorexia nervosa (AN) and may also moderate the behavioral manifestation of AN. This review aims to provide an overview of AN and comorbid ASD.

RECENT FINDINGS

Elevated ASD traits do not seem to precede AN among some individuals but are rather related to the illness stage. However, studies have suggested that there are ASD-specific mechanisms for developing AN in a subgroup of individuals with AN. Pronounced traits of ASD and diagnosed ASD are associated with illness prolongation and poorer outcomes in AN, and individuals with AN and elevated ASD traits may benefit less from many of the current treatments. Studies do not support a specific genetic relationship between ASD and AN.

SUMMARY

Recent research encourages the improved recognition of elevated ASD traits in individuals with AN and provides grounds for developing tailored treatments for those with this comorbidity.

The Neuropsychological Profile of Severe and Enduring Anorexia Nervosa: A Systematic Review

Characteristics of Severe and Enduring Anorexia Nervosa (SE-AN) are being investigated to differentiate the patients experiencing SE-AN from those at earlier stages of the AN disease. The current systematic review was the first step in exploring neuropsychological functioning as a potentially identifying characteristic for long-term presentations. With a subgroup of AN patients reflecting a unique neuropsychological profile that is proportionate to the quantity of patients that go on to develop SE-AN, it was the aim of this review to assess neuropsychological functioning in the later stage of the disease. In accordance with PRISMA guidelines, a literature search was conducted using four electronic databases (PsycINFO, MEDLINE, Web of Science, and Scopus) for neuropsychological research on AN participants with a seven or more year illness duration. Datasets that met inclusion criteria were screened for SE-AN participants (N = 166) and neuropsychological data extracted together with potentially confounding variables and information required to conduct a quality assessment. In research investigating decision-making, participants with a SE-AN presentation demonstrated significantly lower functioning compared to healthy controls. There was conflicting evidence for differences in intellectual functioning and set-shifting abilities with no variability indicated in central coherence, memory, attention, reasoning, or processing speed. If findings from this preliminary analysis are confirmed through empirical research, implications include earlier identification of SE-AN patients and more effective treatment development.

The role of food selectivity in the association between child autistic traits and constipation

OBJECTIVE

This study examines the association between child autistic traits and constipation symptoms, and explores whether this association is mediated by food selectivity.

METHOD

The sample included participants (N = 2,818) from the population-based birth cohort, Generation R (Rotterdam, the Netherlands). Parents reported their child's autistic traits at 6 years (using the Social Responsiveness Scale), food selectivity at 10 years (using the Stanford Feeding Questionnaire) and the frequency and severity of constipation symptoms they experienced at 10 years (using the ROME III functional constipation diagnostic criteria). Mediation analyses tested mediation through food selectivity in the association of autistic traits and the number of constipation symptoms, adjusting for covariates.

RESULTS

There was a positive association between parent-reported child autistic traits and constipation symptoms (r = 0.08, p < .001). We identified a significant indirect effect of autistic traits on constipation symptoms through food selectivity (β = 0.008, 95% Confidence Interval: 0.002, 0.014).

DISCUSSION

This study provides empirical support for the mediating role of food selectivity in the association between autistic traits and constipation. Behavioral interventions aimed to target food selectivity and support families of children with autistic traits may bolster conventional medical and nutritional treatments to alleviate gastrointestinal symptoms like constipation.

Prevalence of autism spectrum disorder and autistic traits in children with anorexia nervosa and avoidant/restrictive food intake disorder

BACKGROUND

Autism spectrum disorder (ASD) and feeding and eating disorders (FEDs) such as anorexia nervosa (AN) are strongly linked as evidenced by frequent comorbidity and overlapping traits. However, eating and social behaviors are shaped by culture, so it is critical to examine these associations in different populations. Moreover, FEDs are heterogeneous, and there has been no examination of autistic traits in avoidant/restrictive food intake disorder (ARFID).

METHODS

Therefore, we investigated the prevalence of ASD and autistic traits among Japanese children with AN (n = 92) or ARFID (n = 32) from a prospective multicenter cohort study using the Autism Spectrum Quotient Children's version (AQC) and Children's Eating Attitudes Test (ChEAT26).

RESULTS

ASD prevalence was high in both AN and ARFID (16.3 and 12.5%, respectively). The AN group exhibited significantly higher scores on all AQC subscales than an age-matched healthy control (HC) group, but there were no significant correlations between AQC scores and ChEAT26 scores. In the AFRID group, AQC scores did not differ from HCs, but significant correlations were found between total AQC and ChEAT26 scores and between several AQC and ChEAT26 subscales.

CONCLUSIONS

Both the AN and ARFID groups had high prevalence rates of ASD. The AN group showed a significantly higher degree of autistic traits than the HC group; however, no difference was found between the ARFID and HC groups. Clinicians need to be aware of these rates when working with children with ED.

Central coherence and set-shifting between nonunderweight eating disorders and anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis compared previously documented inefficiencies in central coherence and set-shifting between people with nonunderweight eating disorders (bulimia nervosa and binge-eating disorder) and people with anorexia nervosa.

METHOD

We performed random-effects meta-analyses on 16 studies (1,112 participants) for central coherence and 38 studies (3,505 participants) for set-shifting. Random effects meta-regressions were used to test whether the effect sizes for people with nonunderweight eating disorders were significantly different from the effect sizes for people with anorexia nervosa.

RESULTS

People with anorexia nervosa (Hedge's g = -0.53, 95% CIs: -0.80, -0.27, p < .001) and bulimia nervosa (Hedge's g = -0.70, 95% CIs: -1.14, -0.25, p = .002), but not binge-eating disorder, had significantly poorer central coherence than healthy controls. Similarly, people with anorexia nervosa (Hedge's g = -0.38, 95% CIs: -0.50, -0.26, p < .001) and bulimia nervosa (Hedge's g = -0.55, 95% CIs: -0.81, -0.29, p < .001), but not binge-eating disorder, had significantly poorer set-shifting than healthy controls. The effect sizes for people with nonunderweight eating disorders did not significantly differ from those for people with anorexia nervosa.

DISCUSSION

Our meta-analysis was underpowered to make definitive judgments about people with binge-eating disorder. However, we found that people with bulimia nervosa clearly have central coherence and set-shifting inefficiencies which do not significantly differ from those observed in people with anorexia nervosa. Clinically, this suggests that people with bulimia nervosa might benefit from adjunctive approaches to address these inefficiencies, such as cognitive remediation therapy.

The autism diagnostic observation schedule: Patterns in individuals with anorexia nervosa

OBJECTIVE

Studies have used the Autism Diagnostic Observation Schedule (the ADOS-2) in individuals with anorexia nervosa (AN), but the patterns of scores have not been assessed. We examined which subset of the ADOS-2 items best discriminate individuals with AN from healthy controls (HC), and assessed the potential clustering of AN participants based on different profiles of the ADOS-2 item scores.

METHOD

We combined datasets from two previous studies, and (a) compared mean ranks between young AN participants (N = 118) and HC (N = 42), (ii) replicated the item selection procedure of the existing ADOS-2 algorithm to assess sensitivity of items in the AN group, and (c) applied a two-step clustering analysis in the AN group (N = 149).

RESULTS

AN participants displayed significantly higher mean ranks than HC participants in five of 32 items. All five items are part of the existing ADOS-2 algorithm. We found two clusters of AN participants; one representing normal social behaviour, comprising 68% of the individuals with AN, and one representing less efficient social behaviour, comprising 32% of individuals with AN.

CONCLUSIONS

The items comprising the social affective cluster of the existing ADOS-2 algorithm are well suited to assess difficulties with social functioning in individuals with AN.

Pragmatic Sensory Screening in Anorexia Nervosa and Associations with Autistic Traits

BACKGROUND

Research suggests that people with anorexia nervosa (AN) experience subjective hypersensitivity to external sensations that may require consideration in treatment. These difficulties may be particularly pronounced in people with AN and high autistic traits. The purpose of this pilot study was to explore the use of a brief screening tool to assess sensory sensitivity in individuals receiving treatment for AN, and to assess if self-rated sensitivity in AN is related to autistic traits.

METHODS

47 individuals receiving treatment for AN completed a brief sensory screening tool and self-rated their autistic traits. Individuals were also asked to give qualitative feedback on the screening tool.

RESULTS

People with AN and high autistic traits rated themselves as more hypersensitive compared to people with AN and low autistic traits. Feedback surrounding the use of the screener was positive.

CONCLUSIONS

The results of this study suggest that the use of this screener may be beneficial in eating disorder settings to help adjust and calibrate treatment to personal needs, although further research and psychometric evaluation around the clinical use of the screener is required. The finding that people with AN and high autistic traits may experience elevated hypersensitivity also warrants further exploration in future research.