Early change in gastric-specific anxiety sensitivity as a predictor of eating disorder treatment outcome

Eating disorders (EDs) are often accompanied by gastrointestinal (GI) distress. Anxiety sensitivity is the tendency to interpret sensations of anxiety as threatening or dangerous, and includes both broad physical symptoms (e.g., elevated heartrate) and GI-specific symptoms. Physical and GI-specific anxiety sensitivity may be important risk and maintaining factors in EDs. This study tested the hypothesis that greater reductions in both types of anxiety sensitivity during the first month of treatment would predict lower ED symptoms and trait anxiety at discharge and 6-month follow-up. Patients (n = 424) in ED treatment reported physical and GI-specific anxiety sensitivity, ED symptoms, and trait anxiety at treatment admission, 1-month into treatment, discharge, and 6-month follow-up. Analyses were conducted with hierarchical linear regression with imputation, controlling for relevant covariates. Results indicated that early reduction in GI-specific but not general physical anxiety sensitivity predicted both lower ED symptoms and lower trait anxiety at discharge and 6-month follow-up. These findings demonstrate the importance of GI-specific anxiety sensitivity as a potential maintaining factor in EDs. Developing and refining treatments to target GI-specific anxiety sensitivity may have promise in improving the treatment not only of EDs, but also of commonly co-morbid anxiety disorders.

A naturalistic examination of feeling fat: Characteristics, predictors, and the relationship with eating disorder behaviors

OBJECTIVE

Although literature implicates feeling fat in the maintenance of binge-spectrum eating disorders (EDs; e.g., bulimia nervosa, binge-ED), research in this area is small, nascent, and relies on retrospective self-report. The current study sought to understand the temporal pattern of feeling fat and its role as a precipitant and consequence of ED behaviors.

METHODS

Totally 106 treatment-seeking adults with binge-spectrum EDs completed 7-14-day ecological momentary assessments. They rated feeling fat, negative affect states, and reported on ED behaviors six times per day. Multilevel models evaluated whether feeling fat mediates prospective links between negative affect states and ED behaviors, assessed if negative affect states mediate the prospective association of feeling fat on ED behaviors, and examined the bidirectional prospective association between feeling fat and ED behaviors.

RESULTS

Feeling fat was highest in the early morning (6-8:59 a.m.). Individuals with binge-ED-spectrum EDs demonstrated greater variability in feeling fat than those with bulimia nervosa-spectrum EDs who had stable and high levels of feeling fat. Guilt, sadness, anxiety, and the overall NA at Time 2 mediated the prospective associations between at Time 1 feeling fat and Time 3 dietary restraint, actual dietary restriction, and compensatory exercise. There was a bidirectional prospective association between feeling fat and binge eating.

DISCUSSION

Feeling fat serves as a proximal predictor and mediator of the prospective association between guilt and binge eating. Feeling fat and binge eating mutually reinforce each other.

PUBLIC SIGNIFICANCE

Little is understood regarding the experience of feeling fat in natural environments among individuals with binge-spectrum eating disorders. We found that the risk for having the experience of feeling fat is high in the morning and evening. Feeling fat triggers guilt, anxiety, and sadness which in turn, increases engagement in dietary restraint/restriction and compensatory exercise. Feeling fat also triggers binge eating, and binge eating leads to feelings of fatness.

Is Interoception Deficit Linking Alexithymia and Eating Spectrum Symptoms? Study on a Non-Clinical Sample of Young Adults

We investigated if interoceptive deficits could be the link between alexithymic traits and eating spectrum manifestations in a non-clinical sample. One-hundred sixty-one young adults (mean age: 23.2 ± 2.4 years) were evaluated with the Toronto Alexithymia Scale-20 (TAS-20), the Interoceptive Accuracy Scale (IAS), the Interoceptive Confusion Questionnaire (ICQ), and the Eating Attitudes Test-26 (EAT-26). Questionnaires were administered with an online procedure (Microsoft Form, Office 365 A1, Pisa, Italy) (Study Protocol #0012005/2023). We compared ICQ, IAS, and TAS-20 scores in subjects who met the threshold for a potential eating spectrum disorder according to EAT-26 scores ≥ 20 (n = 27) vs. subjects who scored <20 (n = 134), with an ANCOVA corrected for 'age' and 'gender'. Subjects with EAT-26 ≥ 20, scored significantly higher at ICQ (54.4 ± 13.2 vs. 50.2 ± 6.8; p = 0.011), TAS-20 'Total Score' (60.8 ± 11.9 vs. 58.1 ± 9.2; p = 0.006), and TAS-20 'Identifying Feelings' (21.5 ± 7.6 vs. 17.3 ± 5.8; p = 0.0001). A binary logistic regression analysis, with EAT-26 scores < 20 vs. ≥20 as the dependent variable, and ICQ, IAS, TAS-20 total scores and dimensions, age, and gender (categorical) as covariates, showed that the only variable predicting eating spectrum symptomatology was 'ICQ Total Score' (OR = 1.075, 95% CI: 1.016-1.139; p = 0.013). Interoceptive confusion was the dimension linking the occurrence of alexithymic traits and eating spectrum manifestations.

Recognition of others' interoceptive states in those with and without eating disorders

BACKGROUND

The ability to recognize one's own emotions is associated with one's ability to recognize others' emotions. Beyond the domain of emotion, however, the relationship between recognition of one's own internal states (interoception) and others' interoceptive states has not been investigated, either in the typical population or clinical groups with interoceptive difficulties (e.g. eating disorders; EDs).

METHOD

This study investigated recognition of one's own and others' internal states in adults with and without eating disorders, using a high frequency visual noise paradigm. Participants completed self-report measures of interoception, alexithymia (difficulties recognising one's own emotional internal states) and ED symptomatology, and the Heartbeat Counting Task measure of cardiac interoceptive accuracy.

RESULTS

Alexithymia was significantly negatively correlated with recognition of others' interoceptive states. EDs were not associated with difficulties recognising others' interoceptive states.

CONCLUSIONS

The ability to recognise one's own emotional internal states is associated with the recognition of others' interoceptive states, which may contribute to social skills and the ability to care for others.

Elevated interoceptive deficits in individuals with eating disorders and self-injurious thoughts and behaviors: A replication and extension

INTRODUCTION

People with eating disorders (EDs) frequently report self-injurious thoughts and behaviors (SITBs). We aimed to replicate and extend findings demonstrating greater interoceptive deficits according to SITB severity. We predicted that interoceptive deficits would be greater among people with versus without lifetime SITBs and among those with multiple suicide attempts compared with single attempts or nonsuicidal self-injury. We also predicted that interoception would be increasingly impaired with greater current suicidality severity.

METHOD

Adults (N = 118) seeking ED treatment reported current and lifetime SITBs upon admission to treatment. We used planned contrasts to compare interoceptive deficits (self-reported using the Eating Disorders Inventory) by SITB and current suicidality groups (assessed by self-report and clinical interview).

RESULTS

Interoceptive deficits were greater among people with any SITB history compared to those without. People with multiple suicide attempts did not differ in interoceptive deficits from those with single attempts or only nonsuicidal self-injury. Interoceptive deficits were elevated among those with any current suicidality compared to those with no suicidal symptoms; interoceptive deficits did not differ according to severity of suicidality.

CONCLUSION

Among those with EDs, interoceptive deficits are elevated among those with concurrent SITBs. Interventions aimed at improving interoception may reduce the risk for SITBs.

An examination of eating disorder fears in imaginal exposure scripts

OBJECTIVE

Eating disorders (EDs) are maintained by fear and anxiety, which lead to disordered eating behaviors thought to prevent the occurrence of feared outcomes. Fear of weight gain and food are among the most common fears present in the EDs. However, theory and clinical observation suggest that the feared consequences of eating or weight gain are diverse and individualized. Further research is needed to delineate specific fears underlying ED pathology.

METHOD

167 participants with any ED participated in an online four-session imaginal exposure intervention. Imaginal exposure scripts were rated by trained coders using items derived from the Eating Disorder Fear Interview to identify fears present. Frequencies of fears present in scripts were quantified.

RESULTS

Two-thirds of scripts mentioned fears of food and weight or body-related fears. In over half of scripts, fear of judgment and fear of loss of control were identified. Diagnostic differences were found, including that those with anorexia nervosa (AN) and bulimia nervosa (BN) had highest fears of food, whereas those with AN and other specified feeding and eating disorder (OSFED) had higher weight gain/body-focused fears.

LIMITATIONS

We were underpowered to make comparisons between ED diagnoses other than AN, BN, and OSFED.

CONCLUSIONS

Imaginal exposure scripts contained a large number of fears related to food, weight/shape, judgment, and loss of control, among others. These findings extend the current understanding of ED fears and provide evidence for the individualized and varied nature of fears. Identification of ED fears can further inform research on designing personalized, exposure-based treatment approaches.

The structure of eating disorder and somatic symptoms

Individuals with eating disorders (EDs) often present with somatic concerns in treatment, such as bloating, fullness, and feeling tight clothes on skin. However, most research generally focuses on general interoception (e.g., heartbeat) rather than sensations relevant to EDs (e.g., sensations related to the gastrointestinal system or body movement). In the current study (N = 181), we used network analysis to model the structure of ED symptoms and somatic concerns among individuals with anorexia nervosa, bulimia nervosa, and other specified feeding and eating disorder. Results showed that heightened sensitivity to somatic concerns had the highest strength centrality within a symptom network comprising ED and somatic symptoms. Exploratory graph analysis identified four symptom dimensions: cognitive-affective ED symptoms, behavioral ED symptoms, general interoception, and ED-specific proprioception. Findings suggest that heightened sensitivity to somatic concerns may maintain ED symptoms and mutually reinforce other somatic concerns. Implications concerning assessment and treatment of EDs are discussed.

Time evaluation and its accuracy in eating disorders: differences in relation to interoceptive awareness

PURPOSE

Time evaluation has been poorly studied in eating disorder (ED) patients despite its relationship with body awareness, which is a core psychopathological feature in EDs and is influenced by impulsivity, interoception, and working memory. This study aims to evaluate time estimation and its accuracy across the ED spectrum in connection with specific and general psychopathology.

METHODS

A group of 215 women was enrolled in a computerized task involving the estimation of 1-min intervals. Impulsivity and body awareness constructs (self-monitoring, depersonalization, interoceptive deficit) were evaluated and examined for significant correlations with time estimation and the accuracy of the measure.

RESULTS

Patients with EDs showed an impaired ability to estimate time, with an accuracy that positively correlated with compulsive self-monitoring (p = 0.03). Differences between diagnostic subgroups showed an overestimation of time in anorexia nervosa patients and an underestimation of time in binge eating disorder patients, whose time estimation was also less accurate.

CONCLUSION

The relationship between time estimation and compulsive self- monitoring might corroborate the presence of an imbalanced integration of information in patients with EDs that was not present in the community women included in the study. Time perception should be further evaluated in the ED field, and longitudinal changes due to psychopathological recovery or BMI changes should be examined.

LEVEL OF EVIDENCE

Level III: Evidence obtained from a well-designed cohort or case-control analytic study.

Validating the visceral sensitivity index in an eating disorder sample

OBJECTIVE

Individuals with eating disorders (EDs) often have difficulty tolerating uncomfortable body sensations. As such, anxiety sensitivity specific to gastrointestinal (GI) sensations, has relevance for EDs. However, to date, no validated measures of this construct exist in EDs. Thus, the present study sought to validate the visceral sensitivity index (VSI), a 15-item measure originally validated in an irritable bowel syndrome sample, in an ED sample and explore associations with ED symptoms.

METHOD

Two hundred and sixty-six adolescents (n = 116) and adults (n = 150) in an ED partial hospital program completed the VSI and related measures at admission. Confirmatory factor analysis examined the factor structure of the VSI and hierarchical regression analyses explored associations between the VSI and ED symptoms.

RESULTS

The original version of the VSI had adequate model fit. An alternative 13-item model removing specific items with poor fit and less theoretical relevance to EDs also demonstrated good fit. The 15-item and 13-item VSI had strong internal consistency (α = .93-.94), and correlation results supported the convergent and divergent validity of both versions. Higher visceral sensitivity was associated with elevated body dissatisfaction, cognitive restraint, purging, restricting, and excessive exercise (p-values <.05), beyond length of illness, body mass index, and trait anxiety.

DISCUSSION

Results support the relevance of GI-specific anxiety in EDs and suggest that the original 15-item VSI and modified 13-item VSI have strong psychometric properties in an ED sample. Given comparable model fit and psychometric properties, both versions of the VSI may be used for future ED research.

The Role of Disgust in Eating Disorders

PURPOSE OF REVIEW

In current review, we evaluate the current literature examining the role of disgust in eating disorders (EDs), and provide a theoretical model designed to inform the study and treatment of disgust-based symptoms in EDs.

RECENT FINDINGS

Findings from this review suggest that aberrant disgust-conditioning processes represent promising but understudied mechanisms that may contribute to the risk and maintenance of core eating disorder (ED) psychopathology. In addition, preliminary evidence supports the use of interventions designed to target aversive disgust cues and disrupt maladaptive disgust-based conditioning that may maintain eating pathology. However, experimental studies designed to elucidate the role of disgust and aversive learning processes remain limited. Disgust is a promising risk and maintenance factor in EDs. Future systematic investigation is needed to examine disgust-based processes at a mechanistic level in order to better understand the links between disgust, avoidance behaviors, and EDs. Further investigation of the mechanistic role of disgust in EDs is warranted.

Body Trust, agitation, and suicidal ideation in a clinical eating disorder sample

OBJECTIVE

Research has established pairwise relationships between suicidal ideation (SI), low Body Trust, elevated agitation, and eating disorders, but knowledge of how these aspects relate in a single model is lacking. This study tested an indirect pathway with low Body Trust relating to severity of SI via agitation in a clinical eating disorder sample.

METHOD

Participants (N = 319; 92.8% female; 93.4% Caucasian; mean age 21.8 years) were adults currently receiving specialized eating disorder treatment (44.3% intensive outpatient or higher level-of-care) who completed online self-report measures of study variables. The PROCESS macro was utilized to test proposed pathways.

RESULTS

Low Body Trust was significantly directly associated with increased severity of current SI, both before (B = -.89, p < .001) and after (B = -.51, p = .001) accounting for the indirect effect through agitation, also significant (B = -.37, SE = .06, CI -.52 to -.26).

DISCUSSION

Perception of the body as unsafe may be related to agitation, and this intolerable sensation of trapped arousal could contribute to a desire to die. Future work should investigate these relationships prospectively to determine the relevance of Body Trust for assessment and treatment of suicide-related factors among individuals with eating disorders.

Understanding "feeling fat" and its underlying mechanisms: The importance of multimethod measurement

"Feeling fat," the somatic sensation of being overweight that does not entirely correlate with one's actual weight, is recognized clinically as a maintenance factor in eating disorders. Occurring amidst Western internalized thin ideals and weight stigma, "feeling fat" is wide-reaching and also reported by those with subclinical and absent eating pathology. However, empirical study of "feeling fat" is limited. Regarding proposed mechanisms, "feeling fat" may (a) reflect the displacement of negative affect onto the body, (b) represent one element of a cognitive distortion related to the imagined consumption of fattening food, and/or (c) be a function of impaired interoceptive awareness. However, the relative and/or joint contributions of these mechanisms to "feeling fat" are unclear. Regarding measurement, retrospective assessment with single items has been the norm. Innovative measures of "feeling fat" will expand our understanding of this construct. Ecological momentary assessment can clarify the transitory nature of this experience, and physiological measures can allow for assessment of somatic elements of "feeling fat. Multi-method and implicit measurement strategies of 'feeling fat'" may clarify the mechanisms underlying this experience. Further research with improved measurement techniques may also benefit eating disorder treatment by highlighting new treatment foci (e.g., cognitive distortions, interoceptive awareness).

An Active Inference Approach to Interoceptive Psychopathology

Interoception refers to the process by which the nervous system senses and integrates signals originating from within the body, providing a momentary mapping of the body's internal landscape and its relationship to the outside world. Active inference is based on the premise that afferent sensory input to the brain is constantly shaped and modified by prior expectations. In this review we propose that interoceptive psychopathology results from two primary interoceptive dysfunctions: First, individuals have abnormally strong expectations of the situations that elicit bodily change (i.e., hyperprecise priors), and second, they have great difficulty adjusting these expectations when the environment changes (i.e., context rigidity). Here we discuss how these dysfunctions potentially manifest in mental illness and how interventions aimed at altering interoceptive processing can help the brain create a more realistic model of its internal state.

The Role of Interoception in the Pathogenesis and Treatment of Anorexia Nervosa: A Narrative Review

Anorexia nervosa (AN) is a psychiatric illness characterized by extreme overvaluation of weight and disturbed eating. Despite having the highest mortality rate of any psychiatric illness, the etiology and neurobiology of AN are poorly understood. A growing body of research has begun to elucidate the role of reward processing, as well as cognitive and limbic networks, in the symptomology of AN. However, these advances have so far failed to contribute therapeutically, suggesting a new understanding may be necessary. A disturbance in the interoceptive system, involved in perceiving and interpreting the physiological condition of the body, has recently been proposed as a central mechanism of pathology in AN, through links to hunger and satiety, risk prediction errors, emotional awareness, and body dysmorphia. This review summarizes the existing literature in order to clarify possible underlying mechanisms and proposes a novel model of the neuro-circuitry of AN. Detailed neuroanatomical studies and new methods for studying interoception may allow further refinement of this model and the development of improved treatment.

An investigation of indirect effects of personality features on anorexia nervosa severity through interoceptive dysfunction in individuals with lifetime anorexia nervosa diagnoses

OBJECTIVE

This study examined a hypothesized pathway by which interoceptive dysfunction accounted for associations between personality features (harm avoidance, self-directedness, and perfectionism) and anorexia nervosa (AN) severity (indicated by drive for thinness, eating disorder-related preoccupations and rituals, and body mass index).

METHOD

The study sample (n = 270, mean age = 28.47, 95.2% female, 98% White/Caucasian) consisted of probands and biological relatives who met DSM-IV criteria for lifetime diagnoses of AN (omitting criterion D, amenorrhea) drawn from the Price Foundation Anorexia Nervosa Affected Relative Pairs Study (AN-ARP). Participants completed measures assessing personality, interoceptive dysfunction, and eating pathology.

RESULTS

Associations between personality features of low self-directedness and high perfectionism and indicators of AN severity (drive for thinness and eating disorder-related preoccupations and rituals) were significant, as were the hypothesized indirect pathways through interoceptive dysfunction. Neither harm avoidance nor body mass index was significantly related to other study variables, and the proposed indirect pathways involving these variables were not significant.

DISCUSSION

Findings suggest that certain personality features may relate to AN severity, in part, through their associations with interoceptive dysfunction. Future research should examine prospective associations and the value of interventions targeting interoceptive dysfunction for interrupting the link between personality and AN severity.

Body trust as a moderator of the association between exercise dependence and suicidality

OBJECTIVES

Exercise dependence and interoceptive deficits, particularly low body trust, have been associated with suicidality. This study tested whether low body trust predicted current suicidal ideation and past suicide attempts in individuals exhibiting symptoms of exercise dependence.

METHODS

540 individuals (55.6% female, mean age 36) recruited via MTurk completed online measures of exercise dependence, interoception, and history of suicidal ideation and attempts.

RESULTS

Exercise dependence symptoms and low body trust were associated with suicidal ideation. Body trust moderated the relationship between exercise dependence symptoms and suicidal ideation. Continuance in exercise despite adverse consequences and low body trust were associated with past suicide attempts.

CONCLUSIONS

Body trust was associated with suicidal ideation and suicide attempts in individuals with exercise dependence symptoms, and the associations strengthened as body trust decreased. The experience of not trusting one's own body may exacerbate suicide risk in at-risk individuals.