Validating the visceral sensitivity index in an eating disorder sample

Development and Psychometric Validation of the Body Trust Scale

Interoception (e.g., abilities to recognize/attend to internal sensations) is robustly associated with psychopathology. One form of interoception, body trust, is relevant for the development of disordered eating and suicidal thoughts/behaviors. However, measures of body trust are narrow, despite research suggesting body trust is multifaceted. The aim of this study was to develop a comprehensive measure of body trust: The Body Trust Scale (BTS). 479 U.S. adults completed self-report surveys containing the BTS and psychopathology measures. Exploratory and confirmatory factor analyses revealed a three-factor structure: Comfort with One's Body, Physical Attractiveness, and Comfort with Internal Sensations. Factors showed strong construct, convergent, and divergent validity, as well as moderate predictive validity for suicidal thoughts/non-suicidal self-injury. Furthermore, factors showed strong internal consistency, test-retest reliability, and were invariant across the gender binary. The BTS can be used in research and clinical settings to understand how specific facets of body trust relate to psychopathology.

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.

Further validation of the visceral sensitivity index: Psychometric properties and utility for predicting disordered eating in a diverse university sample

Gastrointestinal (GI) visceral sensitivity (i.e., anxiety/worry over GI sensations) may be a key maintaining factor for disordered eating; however, it is unknown whether GI visceral sensitivity predicts the range of disordered eating behaviors in nonclinical samples. The current preregistered study aimed to replicate previous construct validity findings of the Visceral Sensitivity Index (VSI; i.e., factor structure, convergent and discriminant validity) and examine its criterion-related validity for predicting a range of disordered eating attitudes and behaviors in a diverse undergraduate sample. A total of 591 university students were retained in the final analytic sample (53 % women; 23 % Hispanic [Any Race], 10 % Asian, 9 % Black) and completed the VSI, disordered eating, and additional validity measures. A confirmatory factor analysis tested the factor structure of the VSI, and correlations were used to examine convergent and discriminant validity. Hierarchical regressions and t-tests were used to examine criterion-related validity. Results replicated previous construct validity findings in a diverse undergraduate sample. Exploratory analyses supported invariance of the VSI across gender and the VSI discriminated between individuals at high- versus low-risk for an eating disorder and predicted a range of disordered eating attitudes (e.g., body dissatisfaction) and behaviors (e.g., restricting, binge eating, purging, compulsive exercise). GI-specific anxiety appears to be transdiagnostic across disordered eating behaviors and relevant across the spectrum of disordered eating severity. Future work may include developing transdiagnostic models of GI visceral sensitivity in disordered eating and investigating inclusion of the VSI in university screening efforts.

VISCERAL SENSITIVITY INDEX (VSI-IT): Italian Adaptation and Validation

The Visceral Sensitivity Index (VSI) represents a significant advancement in the assessment of gastrointestinal-specific anxiety among patients with irritable bowel syndrome (IBS) and chronic inflammatory bowel diseases (IBD)-such as ulcerative colitis and Crohn's disease. However, an Italian version of the instrument is not yet available for the Italian-speaking population. This study utilized a national sample of 500 individuals divided into four groups: (a) patients with Crohn's disease, (b) patients with ulcerative colitis, (c) patients with IBS, and (d) healthy controls (individuals without any diagnoses) to test the validity and reliability of the Italian VSI. Using back-translation methodology to ensure translation fidelity, this research applied a questionnaire and the VSI through an online format to 500 participants. Confirmatory Factor Analysis (CFA) revealed that the Italian VSI had excellent psychometric properties, demonstrating high internal consistency (Cronbach's α = 0.949) and construct validity. The scale proved sensitive in detecting significant differences in visceral sensitivity among groups, highlighting its utility as a clinical and research assessment tool. Specifically, the Italian VSI exhibited a unidimensional factorial structure and maintained a strong correlation with interoceptive awareness, type of disease, and gastrointestinal symptom severity, confirming its role in enhancing the understanding and management of IBD and IBS in Italy.

Perceptual Dysfunction in Eating Disorders

Eating disorders (EDs) are characterized by abnormal responses to food and weight-related stimuli and are associated with significant distress, impairment, and poor outcomes. Because many of the cardinal symptoms of EDs involve disturbances in perception of one's body or abnormal affective or cognitive reactions to food intake and how that affects one's size, there has been longstanding interest in characterizing alterations in sensory perception among differing ED diagnostic groups. Within the current review, we aimed to critically assess the existing research on exteroceptive and interoceptive perception and how sensory perception may influence ED behavior. Overall, existing research is most consistent regarding alterations in taste, visual, tactile, and gastric-specific interoceptive processing in EDs, with emerging work indicating elevated respiratory and cardiovascular sensitivity. However, this work is far from conclusive, with most studies unable to speak to the precise etiology of observed perceptual differences in these domains and disentangle these effects from affective and cognitive processes observed within EDs. Further, existing knowledge regarding perceptual disturbances in EDs is limited by heterogeneity in methodology, lack of multimodal assessment protocols, and inconsistent attention to different ED diagnoses. We propose several new avenues for improving neurobiology-informed research on sensory processing to generate actionable knowledge that can inform the development of innovative interventions for these serious disorders.

Visceral sensitivity, hunger responsiveness, and satiety responsiveness: Associations between facets of gastrointestinal interoception and disordered eating profiles in an undergraduate sample

This preregistered study examined associations between empirically derived profiles of disordered eating in a diverse nonclinical sample and three facets of gastrointestinal (GI) interoception (visceral sensitivity, hunger responsiveness, satiety responsiveness). University students (n = 591; 53.3% women; 23.0% Hispanic) completed the Visceral Sensitivity Index, Adult Eating Behavior Questionnaire, and Eating Pathology Symptom Inventory. Latent profile analysis was conducted in Mplus v8.3 with four behavioral indicators (restricting, binge eating, excessive exercise, purging [binary]). Facets of GI interoception predicting odds of disordered eating profile membership compared to an asymptomatic group were evaluated. Five profiles were identified. Facets of GI interoception differentially predicted odds of membership in disordered eating profiles. However, higher scores on all three facets of GI interoception were associated with increased odds of membership in a high disordered eating profile. The relationship between distinct facets of GI interoception and specific disordered eating patterns appears nuanced, though individuals displaying a range of disordered eating behaviors may exhibit broad GI interoceptive dysfunction. Findings are consistent with the recent emphasis on idiographic treatment approaches for disordered eating and may have implications for screening among university students. Prospective longitudinal work and extension to clinical samples is needed.

Preliminary data that psychological treatment and baseline anxiety are associated with a decrease in postprandial fullness and early satiation for individuals with bulimia nervosa and related other specified feeding or eating disorder

OBJECTIVE

Gastrointestinal symptoms, particularly postprandial fullness, are frequently reported in eating disorders. Limited data exist evaluating how these symptoms change in response to outpatient psychological treatment. The current study sought to describe the course of postprandial fullness and early satiation across psychological treatment for adults with bulimia nervosa and related other specified feeding or eating disorders and to test if anxiety moderates treatment response.

METHODS

Secondary data analysis was conducted on questionnaire data provided by 30 individuals (80% white, M(SD)age  = 31.43(13.44) years; 90% female) throughout treatment and six-month follow-up in a pilot trial comparing mindfulness and acceptance-based treatment with cognitive-behavioral therapy for bulimia nervosa. Participants completed items from the Rome IV Diagnostic Questionnaire for Adult Functional Gastrointestinal Disorders and the State Trait Anxiety Inventory.

RESULTS

Postprandial fullness and early satiation both significantly decreased over time (ds = 1.23-1.54; p's < .001). Baseline trait anxiety moderated this outcome, such that greater decreases were observed for those with higher baseline anxiety (p = .02).

DISCUSSION

Results extend prior work in inpatient samples by providing preliminary data that postprandial fullness and early satiation decrease with outpatient psychological treatment for bulimia nervosa. Baseline anxiety moderated this effect for postprandial fullness. Future work should replicate findings in a larger sample and test anxiety as a mechanism underlying postprandial fullness in eating disorders.

PUBLIC SIGNIFICANCE

The current study found that common gastrointestinal symptoms (postprandial fullness and early satiation) decrease over the course of outpatient psychotherapy for adults with full and subthreshold bulimia nervosa. Postprandial fullness decreased more across time for those high in anxiety.

Challenges and priorities for researching the gut microbiota in individuals living with anorexia nervosa

OBJECTIVE

The gut microbiota is implicated in several symptoms and biological pathways relevant to anorexia nervosa (AN). Investigations into the role of the gut microbiota in AN are growing, with a specific interest in the changes that occur in response to treatment. Findings suggest that microbial species may be associated with some of the symptoms common in AN, such as depression and gastrointestinal disturbances (GID). Therefore, researchers believe the gut microbiota may have therapeutic relevance. Whilst research in this field is rapidly expanding, the unique considerations relevant to conducting gut microbiota research in individuals with AN must be addressed.

METHOD

We provide an overview of the published literature investigating the relationship between the gut microbiota and symptoms and behaviors present in AN, discuss important challenges in gut microbiota research, and offer recommendations for addressing these. We conclude by summarizing research design priorities for the field to move forward.

RESULTS

Several ways exist to reduce participant burden and accommodate challenges when researching the gut microbiota in individuals with AN.

DISCUSSION

Recommendations from this article are foreseen to encourage scientific rigor and thoughtful protocol planning for microbiota research in AN, including ways to reduce participant burden. Employing such methods will contribute to a better understanding of the role of the gut microbiota in AN pathophysiology and treatment.

PUBLIC SIGNIFICANCE

The field of gut microbiota research is rapidly expanding, including the role of the gut microbiota in anorexia nervosa. Thoughtful planning of future research will ensure appropriate data collection for meaningful interpretation while providing a positive experience for the participant. We present current challenges, recommendations for research design and priorities to facilitate the advancement of research in this field.

Comparing the effect of internet-delivered short-term progressive muscle relaxation and psychoeducation on mindful ability, visceral hypersensitivity and symptoms of patients with irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a functional bowel disorder that psychological interventions are effective on it. The present study aimed to compare the effect of internet-delivered short-term PMR (iPMR) and psychoeducation on mindful ability (MA), visceral hypersensitivity (VH), and symptoms of patients with IBS.

MATERIALS AND METHODS

This randomized clinical trial was performed on individuals with IBS in 2020, recruiting a total of 60 patients fulfilling the inclusion criteria. Prior to the intervention, the Freiburg Questionnaire- Short Form (FMI-SF), the Visceral Sensitivity Questionnaire (VSI), and the Gastrointestinal Symptoms Rating Scale (GSRS) were filled out for the patients. Patients were divided into iPMR and psychoeducation groups randomly. All training in both groups was accomplished via WhatsApp social network. FMI-SF, VSI, and GSRS questionnaires for patients were completed 1 month (post-test) and 2 months later (follow-up). The data was analyzed by SPSS-23 software and one-way analysis of variance (ANOVA).

RESULTS

Compared to the psychoeducation group, the MA of the iPMR group increased significantly in post-test and follow-up (43.06 ± 7.12 and 42.88 ± 6.28 vs 51.23 ± 11.7 and 56.74 ± 12.36 and P < 0.001) and their VH decreased significantly (37.85 ± 11.6 and 38.03 ± 11.8 vs 26.9 ± 6.45 and 22.46 ± 5.32 and P < 0.001). Also, their GSRS had significant decreases (43.27 ± 10.73 and 41.18 ± 9.31 vs 32.33 ± 8.21 and 25.79 ± 6.30 and P < 0.001).

CONCLUSION

The findings showed iPMR in patients with IBS, in spite of a few sessions and internet-delivered approach, increased MA and decreased VH and gastrointestinal symptoms of them.

Impact of auricular percutaneous electrical nerve field stimulation on gut microbiome in adolescents with irritable bowel syndrome: A pilot study

OBJECTIVES

Percutaneous electrical nerve field stimulation (PENFS) has documented efficacy for irritable bowel syndrome (IBS) via plausible vagal neuromodulation effects. The vagus nerve may affect gut microbiome composition via brain-gut-microbiome signaling. We aimed to investigate gut microbiome alterations by PENFS therapy in adolescent IBS patients.

METHODS

A prospective study of females with IBS aged 11-18 years receiving PENFS therapy for 4 weeks with pre- and post-intervention stool sampling was conducted. Outcome surveys completed pre-therapy, weekly, and post-therapy included IBS-Severity Scoring System (IBS-SSS), Visceral Sensitivity Index (VSI), Functional Disability Inventory (FDI), and the global symptom response scale (SRS). Bacterial DNA was extracted from stool samples followed by 16S rRNA amplification and sequencing. QIIME 2 (version 2022.2) was used for analyses of α and β diversity and differential abundance by group.

RESULTS

Twenty females aged 15.6 ± 1.62 years were included. IBS-SSS, VSI, and FDI scores decreased significantly after PENFS therapy (P < 0.0001, P = 0.0003, P = 0.0004, respectively). No intra- or interindividual microbiome changes were noted pre- versus post-therapy or between responders and non-responders. When response was defined by 50-point IBS-SSS score reduction, α diversity was higher in responders compared with non-responders at week 4 (P = 0.033). There was higher abundance of Blautia in excellent responders versus non-responders.

CONCLUSIONS

There were no substantial microbial diversity alterations with PENFS. Subjects with excellent therapeutic response showed an enrichment of relative abundance of Blautia, which may indicate that patients with specific microbial signature have a more favorable response to PENFS.

Gastrointestinal-Specific symptom anxiety in patients with gastroparesis: Relationships to symptom severity and quality of life

BACKGROUND

Gastrointestinal (GI)-specific anxiety has been identified as a treatment target in irritable bowel syndrome. However, GI-specific anxiety has been understudied in other GI functional/motility disorders. Among adults with gastroparesis, we aimed to: (1) initially validate a measure of GI-specific anxiety, the Visceral Sensitivity Index (VSI); and (2) evaluate the relationship between GI-specific anxiety and gastroparesis symptom severity and quality of life, compared to measures of anxiety, depression, and somatization.

METHODS

Consecutive adult patients (N = 100) with gastroparesis presenting for initial consultation completed a series of self-report measures including the VSI. We conducted a confirmatory factor analysis of the VSI one-factor structure and tested internal consistency and convergent validity. We then performed hierarchical linear regression analyses to explore associations between VSI and gastroparesis symptom severity and overall quality of life.

KEY RESULTS

Confirmatory factor analysis revealed that the original VSI one-factor structure overall fit well [χ2 (90) = 220.1, p < 0.0001; SRMR = 0.08; RMSEA = 0.12; CFI = 0.96]. The VSI also had excellent internal consistency (α = 0.99) and convergent validity (r = 0.29-0.56; all p < 0.01). Higher GI-specific anxiety was significantly associated with greater gastroparesis symptom severity, including nausea/vomiting, fullness/satiety, and upper abdominal pain scores beyond depression, anxiety, or somatization (all p = <0.01-0.01). Additionally, higher GI-specific anxiety was significantly associated with lower mental health-related quality of life, beyond gastroparesis symptom severity, depression, anxiety, or somatization (p = 0.01).

CONCLUSIONS & INFERENCES

The VSI is an adequate measure of GI-specific anxiety in patients with gastroparesis. Higher GI-specific anxiety was associated with increased patient-reported gastroparesis symptom severity and decreased quality of life, beyond depression/anxiety.

Examination of the two-step water load test as a measure of gastric interoception and associations with eating and weight/shape concerns in a nonclinical sample

OBJECTIVE

The current study extended research examining the validity of the two-step Water Load Test (WLT-II), an objective, laboratory-based measure of gastric interoception, by investigating the validity of the WLT-II in a nonclinical sample and testing its contribution to the prediction of eating and weight/shape concerns.

METHODS

Participants (n = 129, 73.6% cisgender female, M = 20.13 years old) completed the WLT-II Questionnaire and two-step WLT-II, as well as self-report measures of eating and weight/shape concerns (Eating Disorder Examination Questionnaire; EDE-Q) and interoception (Multidimensional Assessment of Interoceptive Awareness-2; Intuitive Eating Scale-2 Reliance on Hunger and Satiety), in the lab at a large southeastern university. Data analysis included repeated measures ANOVA, correlations, and a series of hierarchical linear regressions.

RESULTS

Participants reported considerably more discomfort after the "maximum fullness" trial compared to the "satiation" trial. The WLT-II's objective measure of gastric interoception (sat_%) was not significantly correlated with the self-report measures of interoception and did not predict EDE-Q Dietary Restraint, Eating Shame, or Weight/Shape Concerns. Unexpectedly, greater gastric sensitivity was associated with less EDE-Q Preoccupation/Restriction. Exploratory analyses suggested a possible nonlinear association.

DISCUSSION

These results support the validity of the WLT-II in its ability to create, measure, and distinguish between the states of satiation and maximum fullness. However, results also suggest additional work is needed to better understand what the WLT-II's sat_% measure is capturing, as well as investigate potential nonlinear associations of the WLT-II with disordered eating.

PUBLIC SIGNIFICANCE

Interoception, or the processing of internal body signals, shows important links to disordered eating. Despite the clear relevance of gastric interoception to disordered eating-such as the ability to detect satiety signals-existing research has relied on general, self-report measures of interoception. This study examined the utility of a laboratory-based measure of gastric interoception. Results suggested mixed support for its validity and utility for predicting eating and weight/shape concerns in a nonclinical population.

Diet, Digestion, and the Dietitian: A Survey of Clinicians' Knowledge, Attitudes and Practices to Advance the Treatment of Gastrointestinal Disturbances in Individuals with Anorexia Nervosa

Despite advances in treatment of anorexia nervosa (AN), current therapeutic approaches do not fully consider gastrointestinal disturbances (GID), often present in AN. Addressing GID, both symptoms and disorders, is likely to improve treatment adherence and outcomes in people with AN. GID are complex and are linked to a range of factors related to eating disorder symptomology and can be impacted by nutritional treatment. It is not known which dietetic practices are currently used to address GID in AN. Therefore, this survey aimed to explore the perceived knowledge, attitudes, and practices (KAP) of Australian dietitians treating AN and co-occurring GID. Seventy dietitians participated by completing an online survey. Knowledge scores were calculated based on correct responses to knowledge items (total: 12 points); and two groups were generated: higher knowledge (≥10 points, n = 31) and lower knowledge (≤9 points, n = 39). A greater proportion of dietitians with higher knowledge recognized the role of GID in pathogenesis of AN (p = 0.002) and its impact on quality of life (p = 0.013) and screened for GID (p ≤ 0.001), compared with those with lower knowledge. These results suggest that attitudes and practices toward patients presenting with AN and GID differ depending on level of knowledge. This may have important implications for treatment outcomes for individuals with AN and GID.

General versus hunger/satiety-specific interoceptive sensibility in predicting disordered eating

Dysfunctional interoceptive processing of hunger and satiety cues is particularly relevant to disordered eating behaviors. However, researchers often rely on general measures of interoceptive sensibility (IS¹; self-reported experience of internal bodily cues) which conflate interoceptive processes across biological systems (e.g., gastric, cardiac) when assessing the role of interoception in disordered eating. Participants (N = 213; 50% female, age M = 20.77 years) were recruited from a large southeastern university for this online study and completed the Intuitive Eating Scale-2 (hunger/satiety-specific), the Multidimensional Assessment of Interoceptive Awareness-2 (general), and the Eating Disorder Inventory Interoceptive Awareness Subscale (general) as measures of IS. The Eating Pathology Symptoms Inventory was used to assess disordered eating attitudes and behaviors. Controlling for sex and body mass index, hunger/satiety-specific IS was associated with binge eating, purging, and cognitive restraint over and above general IS measures and emerged as the dominant predictor of each. Hunger/satiety-specific IS did not predict restricting behavior. Dysfunctional processing of hunger and satiety cues may be a particularly important risk factor to target in screenings and interventions for disordered eating. Findings highlight the importance of careful selection of IS measures in research and targeting hunger/satiety-specific IS in clinical interventions for disordered eating.