Disorders of gut-brain interaction common among outpatients with eating disorders including avoidant/restrictive food intake disorder

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.

Maladaptive weight control and eating behaviours in female adolescents/young adults are associated with increased risk of irritable bowel syndrome in adulthood: Results from the Growing Up Today Study (GUTS)

BACKGROUND

Irritable bowel syndrome (IBS) is common among individuals with eating disorders. The relationship between these conditions is likely bidirectional. However, data on the risk of IBS among those with prior eating disorders is largely limited to cross-sectional studies.

AIM

To prospectively evaluate the association between maladaptive weight control/eating behaviours in females during adolescence/young adulthood with subsequent IBS using the Growing Up Today Study (GUTS).

METHODS

Starting in 1996 (age: 9-14) and during follow-up, participants reported frequency of maladaptive eating/weight control behaviours during the past year to lose weight: self-induced vomiting (n = 5740), laxative use (n = 5438), and fasting (n = 5522) in addition to reporting binge eating (n = 4459). Starting in 2001 and during follow-up, participants reported if they had ever been diagnosed with an eating disorder (n = 5316). Incident IBS cases were identified from four questionnaire cycles (2013, 2014, 2016, 2019), with participants specifying the year of diagnosis if occurring before the questionnaire date. Multivariable logistic regressions adjusting for age, body mass index, and depressive symptoms estimated the associations of interest.

RESULTS

Maladaptive weight control/eating behaviours were associated with increased IBS risk [ORs (95% CIs) for laxatives to lose weight = 3.67 (2.52-5.35), vomiting to lose weight = 1.83 (1.29-2.60), fasting to lose weight = 2.62 (1.86-3.70), and bingeing = 2.25 (1.54-3.28)] as was history of eating disorder diagnosis [OR (95% CI) = 3.42 (2.38-4.90)]. The magnitude of IBS risk increased with the frequency of maladaptive behaviours.

CONCLUSIONS

There is evidence for the potential role of early maladaptive weight control/eating behaviours in the development of adult IBS among females.

Avoidant/Restrictive Food Intake Disorder: Review and Recent Advances

Avoidant/restrictive food intake disorder (ARFID) is an eating disorder recently codified in DSM-5 that affects individuals of all ages. A proliferation of ARFID research has emerged over the years, and this review provides a brief overview of the current understanding of ARFID epidemiology, symptoms, comorbid conditions, assessment, and treatment. The review highlights recent research updates regarding ARFID among adults, putative neurobiological mechanisms underlying ARFID, and new treatment trials. Findings from this review demonstrate that ARFID is as prevalent as other eating disorders, even among adults, and is associated with significant medical and psychiatric comorbid conditions. New, promising treatments for children, adolescents, and adults are in the early stages of development. Several assessments are now available to aid in the screening and diagnosis of ARFID and have demonstrated cross-cultural validity. Areas for future research and clinical guidance, including unresolved questions regarding ARFID categorization and differential diagnosis, are discussed.

Medical Comorbidities, Nutritional Markers, and Cardiovascular Risk Markers in Youth With ARFID

OBJECTIVE

Avoidant/restrictive food intake disorder (ARFID) is common among populations with nutrition-related medical conditions. Less is known about the medical comorbidity/complication frequencies in youth with ARFID. We evaluated the medical comorbidities and metabolic/nutritional markers among female and male youth with full/subthreshold ARFID across the weight spectrum compared with healthy controls (HC).

METHOD

In youth with full/subthreshold ARFID (n = 100; 49% female) and HC (n = 58; 78% female), we assessed self-reported medical comorbidities via clinician interview and explored abnormalities in metabolic (lipid panel and high-sensitive C-reactive protein [hs-CRP]) and nutritional (25[OH] vitamin D, vitamin B12, and folate) markers.

RESULTS

Youth with ARFID, compared with HC, were over 10 times as likely to have self-reported gastrointestinal conditions (37% vs. 3%; OR = 21.2; 95% CI = 6.2-112.1) and over two times as likely to have self-reported immune-mediated conditions (42% vs. 24%; OR = 2.3; 95% CI = 1.1-4.9). ARFID, compared with HC, had a four to five times higher frequency of elevated triglycerides (28% vs. 12%; OR = 4.0; 95% CI = 1.7-10.5) and hs-CRP (17% vs. 4%; OR = 5.0; 95% CI = 1.4-27.0) levels.

DISCUSSION

Self-reported gastrointestinal and certain immune comorbidities were common in ARFID, suggestive of possible bidirectional risk/maintenance factors. Elevated cardiovascular risk markers in ARFID may be a consequence of limited dietary variety marked by high carbohydrate and sugar intake.

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.

Dissecting the biology of feeding and eating disorders

Feeding and eating disorders (FEDs) are heterogenous and characterized by varying patterns of dysregulated eating and weight. Genome-wide association studies (GWASs) are clarifying their underlying biology and their genetic relationship to other psychiatric and metabolic/anthropometric traits. Genetic research on anorexia nervosa (AN) has identified eight significant loci and uncovered genetic correlations implicating both psychiatric and metabolic/anthropometric risk factors. Careful explication of these metabolic contributors may be key to developing effective and enduring treatments for devastating, life-altering, and frequently lethal illnesses. We discuss clinical phenomenology, genomics, phenomics, intestinal microbiota, and functional genomics and propose a path that translates variants to genes, genes to pathways, and pathways to metabolic outcomes to advance the science and eventually treatment of FEDs.

Translation of the nine item avoidant/restrictive food intake disorder screen (NIAS) questionnaire in French (NIAS-Fr)

BACKGROUND

The Nine Item Avoidant/Restrictive Food Intake Disorder (ARFID) Screen (NIAS) questionnaire is originally available in English. Given the significant overlap of ARFID-like symptoms in gastrointestinal (GI) diseases, ARFID screening becomes crucial in these patient populations. Consequently, the translation of the NIAS questionnaire into French is necessary for its utilization in French-speaking countries.

METHODS

Clinical experts in neuro-gastroenterology and dietetics from four medical centres in two French-speaking countries (France and Belgium) took part in a well-structured questionnaire translation procedure. This process involved six steps before final approval: translation from English to French, backward translation, comparison between the original and retranslated versions, testing the translated version on patients, making corrections based on patient feedback, and testing the corrected version on an additional sample of patients.

KEY RESULTS

The NIAS questionnaire in French (NIAS-Fr) was tested on 18 outpatients across the involved centres. For the majority of native French-speaking patients, the translated questionnaire was well understood and clear. After incorporating two relevant modifications suggested by the patients, the translated questionnaire was approved through testing on an additional sample of patients.

CONCLUSIONS AND INFERENCES

The involvement of two French-speaking countries was crucial for the harmonization and cultural adaptation of the questionnaire. As a result, the NIAS-Fr is now available for use in 54 French-speaking countries, serving approximately 321 million French speakers across five continents for screening ARFID, for both clinical and research purposes.

Relationships among symptoms of gastroparesis to those of avoidant/restrictive food intake disorder in patients with gastroparesis

BACKGROUND

Patients with symptoms of gastroparesis (Gp) often reduce food intake in attempt to manage their symptoms. Up to 40% of adults with Gp have been reported to have symptoms of a non-body image-based eating disorder, avoidant/restrictive food intake disorder (ARFID). However, whether ARFID symptoms precede or follow the diagnosis of Gp is unknown.

METHODS

From January 2021 to January 2022, consecutive adult patients with Gp at an academic center completed self-report surveys for Gp symptom severity (patient assessment of upper gastrointestinal symptoms; PAGI-SYM) and for ARFID (nine-item ARFID screen; NIAS).

KEY RESULTS

One hundred and seven patients (age 45.4 ± 17.2 yrs, 84.1% female, BMI 26.4 ± 7.3) with Gp (4-h gastric retention 33.5 ± 21.8%) were included. Eighty-two of the 107 Gp patients (77%) screened positive for ARFID. Positive ARFID screen was most often on the NIAS appetite subscale (84%) and fear subscale (76%), with a lower positive screen rate on the picky subscale (45%). Of the Gp who screened positive for ARFID, 38% reported that eating difficulties came after their Gp diagnosis, whereas 17% reported that eating difficulties preceded their Gp diagnosis, and 15% reported that both began at the same time.

CONCLUSIONS

Many (77%) patients with Gp screened positive for ARFID. In Gp patients with ARFID, the Gp diagnosis was more likely to precede the development of eating difficulties. Thus, a subset of patients with Gp may be at risk for developing ARFID. Further longitudinal research is needed to confirm findings and identify risk factors.

Assessing the presence and motivations of orthorexia nervosa among athletes and adults with eating disorders: a cross-sectional study

PURPOSE

Orthorexia nervosa involves restricting diet based on quality rather than quantity. Although orthorexia is well reported in many at-risk populations, limited data addresses its presence in individuals with eating disorder history (EDs) or athletes. We aimed to identify the presence and potential drivers of orthorexia in adults with EDs and endurance athletes, compared to control subjects.

METHODS

Participants ≥ 18y included: people with a diagnosed eating disorder (ED as per DSM-5); endurance athletes (training/competing ≥ 5 h/week); or control subjects. Participants (n = 197) completed an online survey assessing orthorexia (eating habits questionnaire, EHQ), eating motivations (TEMS-B) and compulsive exercise (CET).

RESULTS

ED had the highest orthorexia symptom severity (92.0 ± 3.02, n = 32), followed by athletes (76.2 ± 2.74, n = 54) and controls (71.0 ± 1.80, n = 111) (F (2) = 18.2, p < 0.001). A strong positive correlation existed between weight control motives and higher orthorexia symptom severity (r = 0.54, 95% CI [1.35, 2.36], p < 0.001), while a weak negative association existed between Hunger and Pleasure motives and higher orthorexia symptom severity (r = 0.23, 95% CI [- 2.24, - 0.34], p = 0.008; r = 0.26, 95% CI [- 2.11, - 0.47], p = 0.002, respectively). A moderate positive relationship was found between CET and orthorexia symptom severity (95% CI [1.52, 3.12], p < 0.001).

CONCLUSION

Adults with ED history and endurance athletes have greater orthorexia symptom severity compared to control. Clinicians working with at-risk populations should screen patients and be aware of red-flags of orthorexic traits, desire to control weight, and compulsive exercise behavior.

LEVEL OF EVIDENCE

III: Evidence obtained from cohort studies.

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.

Brief cognitive-behavioral treatment for avoidant/restrictive food intake disorder in the context of functional dyspepsia: Study protocol for a feasibility randomized controlled trial

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) symptoms are common (up to 40%) among adults with functional dyspepsia (FD), a disorder of gut-brain interaction characterized by early satiation, post-prandial fullness, epigastric pain, and/or epigastric burning. Using an 8-session exposure-based cognitive-behavioral treatment (CBT) for adults with FD + ARFID compared to usual care (UC) alone, we aim to: (1) determine feasibility, (2) evaluate change in clinical outcomes in, and (3) explore possible mechanisms of action.

METHODS

We will randomize adults with FD who meet criteria for ARFID with ≥5% weight loss (N = 50) in a 1:1 ratio to CBT (with continued UC) or to UC alone. A priori primary benchmarks will be: ≥75% eligible participants enroll; ≥75% participants complete assessments; ≥70% participants attend 6/8 sessions; ≥70% of sessions have all content delivered; ≥70% participants rate Client Satisfaction Questionnaire scores above scale midpoint. We will also examine the size of changes in FD symptom severity and related quality of life within and between groups, and explore possible mechanisms of action.

CONCLUSIONS

Findings from this trial will inform next steps with treatment development or evaluation-either for further refinement or for next-step efficacy testing with a fully-powered clinical trial.

Celiac Disease and Disorders of Gut-Brain Interaction: What School Nurses Need to Know

Abdominal pain and discomfort are common reasons students visit the school health office. Abdominal pain, in children, may be related to gastrointestinal conditions such as celiac disease (CD) or disorders of gut-brain interaction (DGBIs). Both CD and DGBIs, formerly known as functional abdominal pain disorders, are both prevalent in the pediatric population. Manifestations, presentation, and management of these disorders overlap and will be reviewed in this article. Due to their chronic nature, school nurses should be aware of both the management and complications associated with CD and DGBIs. Dietary recommendations, including the gluten-free and low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPS) diet, will be presented as part of the management of the disorders.

The Intersection of Disorders of Gut-Brain Interaction With Avoidant/Restrictive Food Intake Disorder

High rates of overlap exist between disorders of gut-brain interaction (DGBI) and eating disorders, for which common interventions conceptually conflict. There is particularly increasing recognition of eating disorders not centered on shape/weight concerns, specifically avoidant/restrictive food intake disorder (ARFID) in gastroenterology treatment settings. The significant comorbidity between DGBI and ARFID highlights its importance, with 13% to 40% of DGBI patients meeting full criteria for or having clinically significant symptoms of ARFID. Notably, exclusion diets may put some patients at risk for developing ARFID and continued food avoidance may perpetuate preexisting ARFID symptoms. In this review, we introduce the provider and researcher to ARFID and describe the possible risk and maintenance pathways between ARFID and DGBI. As DGBI treatment recommendations may put some patients at risk for developing ARFID, we offer recommendations for practical treatment management including evidence-based diet treatments, treatment risk counseling, and routine diet monitoring. When implemented thoughtfully, DGBI and ARFID treatments can be complementary rather than conflicting.

Central Regulation of Eating Behaviors in Humans: Evidence from Functional Neuroimaging Studies

Neuroimaging has great potential to provide insight into the neural response to food stimuli. Remarkable advances have been made in understanding the neural activity underlying food perception, not only in normal eating but also in obesity, eating disorders, and disorders of gut-brain interaction in recent decades. In addition to the abnormal brain function in patients with eating disorders compared to healthy controls, new therapies, such as neurofeedback and neurostimulation techniques, have been developed that target the malfunctioning brain regions in patients with eating disorders based on the results of neuroimaging studies. In this review, we present an overview of early and more recent research on the central processing and regulation of eating behavior in healthy and patient populations. In order to better understand the relationship between the gut and the brain as well as the neural mechanisms underlying abnormal ingestive behaviors, we also provide suggestions for future directions to enhance our current methods used in food-related neuroimaging studies.

Assessment of Patients With ARFID Presenting to Multi-Disciplinary Tertiary Care Program

There are no standard assessment approaches for Avoidant Restrictive Food Intake Disorder (ARFID). We describe our approach to multidisciplinary assessment after assessing more than 550 patients with ARFID. We collected online survey (ARFID-specific instruments, measures of anxiety, depression) measures. Electronic medical record data (mental health and gastrointestinal diagnoses, micronutrient and bone density assessments, and growth parameters) were extracted for the 239 patients with ARFID seen between 2018 and 2021 with both parent and patient responses to online surveys. We identified 5 subtypes/combinations of subtypes: low appetite; sensory sensitivity; fear + sensory sensitivity; fear + low appetite; fear + sensory sensitivity + low appetite. Those with appetite-only subtype had higher mean age (14.0 years, P < 0.01) and the lowest average body mass index z score (-1.74, P < 0.01) compared to other subtypes. Our experience adds to understanding of clinical presentations in patients with ARFID and may aid in assessment formulation.

Development of a brief cognitive-behavioral treatment for avoidant/restrictive food intake disorder in the context of disorders of gut-brain interaction: Initial feasibility, acceptability, and clinical outcomes

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) symptoms are common (up to 40%) among adults with disorders of gut-brain interaction (DGBI), but treatments for this population (DGBI + ARFID) have yet to be evaluated. We aimed to identify initial feasibility, acceptability, and clinical effects of an exposure-based cognitive-behavioral treatment (CBT) for adults with DGBI + ARFID.

METHODS

Patients (N = 14) received CBT as part of routine care in an outpatient gastroenterology clinic. A two-part investigation of the CBT included a retrospective evaluation of patients who were offered a flexible (8-10) session length and an observational prospective study of patients who were offered eight sessions. Feasibility benchmarks were ≥75% completion of sessions, quantitative measures (for treatment completers), and qualitative interviews. Acceptability was assessed with a benchmark of ≥70% patients reporting a posttreatment satisfaction scores ≥3 on 1-4 scale and with posttreatment qualitative interviews. Mixed model analysis explored signals of improvement in clinical outcomes.

RESULTS

All feasibility and acceptability benchmarks were achieved (and qualitative feedback revealed high satisfaction with the treatment and outcomes). There were improvements in clinical outcomes across treatment (all p's < .0001) with large effects for ARFID fear (-52%; Hedge's g = 1.5; 95% CI = 0.6, 2.5) and gastrointestinal-specific anxiety (-42%; Hedge's g = 1.0; 95% CI = 0.5, 16). Among those who needed to gain weight (n = 10), 94%-103% of expected weight gain goals were achieved.

DISCUSSION

Initial development and testing of a brief 8-session CBT protocol for DGBI + ARFID showed high feasibility, acceptability, and promising clinical improvements. Findings will inform an NIH Stage 1B randomized control trial.

PUBLIC SIGNIFICANCE

While cognitive-behavioral treatments (CBTs) for ARFID have been created in outpatient feeding and eating disorder clinics, they have yet to be developed and refined for other clinic settings or populations. In line with the recommendations for behavioral treatment development, we conducted a two-part investigation of an exposure-based CBT for a patient population with high rates of ARFID-adults with disorders of gut-brain interaction (also known as functional gastrointestinal disorders). We found patients had high satisfaction with treatment and there were promising improvements for both gastrointestinal and ARFID outcomes. The refined treatment includes eight sessions delivered by a behavioral health care provider and the findings reported in this article will be studied next in an NIH Stage 1B randomized controlled trial.

History of trying exclusion diets and association with avoidant/restrictive food intake disorder in neurogastroenterology patients: A retrospective chart review

BACKGROUND

Exclusion diets for gastrointestinal symptom management have been hypothesized to be a risk factor for avoidant/restrictive food intake disorder (ARFID; a non-body image-based eating disorder). In a retrospective study of pediatric and adult neurogastroenterology patients, we aimed to (1) identify the prevalence and characteristics of an exclusion diet history and (2) evaluate if an exclusion diet history was concurrently associated with the presence of ARFID symptoms.

METHODS

We conducted a chart review of 539 consecutive referrals (ages 6-90, 69% female) to adult (n = 410; January-December 2016) and pediatric (n = 129; January 2016-December 2018) neurogastroenterology clinics. Masked coders (n = 4) retrospectively applied DSM-5 criteria for ARFID and a separate coder assessed documentation of exclusion diet history. We excluded patients with no documentation of diet in the chart (n = 35) or who were not orally fed (n = 9).

RESULTS

Of 495 patients included, 194 (39%) had an exclusion diet history, and 118 (24%) had symptoms of ARFID. Of reported diets, dairy-free was the most frequent (45%), followed by gluten-free (36%). Where documented, exclusion diets were self-initiated by patients/parents in 66% of cases, and recommended by gastroenterology providers in 30%. Exclusion diet history was significantly associated with the presence of ARFID symptoms (OR = 3.12[95% CI 1.92-5.14], p < 0.001).

CONCLUSIONS

History of following an exclusion diet was common and was most often patient-initiated among pediatric and adult neurogastroenterology patients. As patients with self-reported exclusion diet history were over three times as likely to have ARFID symptoms, providers should be cognizant of this potential association when considering dietary interventions.

The intersection between eating disorders and gastrointestinal disorders: a narrative review and practical guide

Eating disorders include a spectrum of disordered thinking patterns and behaviours around eating. There is increasing recognition of the bi-directional relationship between eating disorders and gastrointestinal disease. Gastrointestinal symptoms and structural issues might arise from eating disorders, and gastrointestinal disease might be a risk factor for eating disorder development. Cross-sectional research suggests that individuals with eating disorders are disproportionately represented among people seeking care for gastrointestinal symptoms, with avoidant-restrictive food intake disorder in particular garnering attention for high rates among individuals with functional gastrointestinal disorders. This Review aims to describe the research to date on the relationship between gastrointestinal disorders and eating disorders, highlight research gaps, and provide brief, practical guidance for the gastroenterology provider in detecting, potentially preventing, and treating gastrointestinal symptoms in eating disorders.

Assessment and management of disorders of gut-brain interaction in patients with eating disorders

Disorders of gut-brain interaction (DBGI), also known as functional gastrointestinal disorders, are common in individuals with eating disorders, and may precede or perpetuate disordered eating. Understanding the pathophysiology of common gastrointestinal symptoms in DGBI can be important for the care of many patients with eating disorders. In this review, we summarize the literature to date on the complex relationship between DBGI and eating disorders and provide guidance on the assessment and management of the most common symptoms of DBGI by anatomic region: esophageal symptoms (globus and functional dysphagia), gastroduodenal symptoms (functional dyspepsia and nausea), and bowel symptoms (abdominal pain, bloating and constipation).

Unrecognized Functional Dyspepsia Among Those With Refractory Chronic Constipation: Analysis of a Tertiary Cohort

BACKGROUND AND AIMS

Patients with functional constipation (FC) are frequently dissatisfied with current treatment options which may be related to persistent, unaddressed symptoms. We hypothesized that refractory FC may actually represent functional dyspepsia (FD) overlap. Among adults presenting with refractory FC, we sought to (1) identify the prevalence of concurrent FD and (2) identify the symptoms and presentations most frequently associated with concurrent FD and FC.

METHODS

We assembled a retrospective cohort of 308 patients sequentially presenting to a tertiary neurogastroenterology clinic for evaluation of refractory FC, defined as having failed first-line therapy. Using Rome IV criteria, trained raters identified the presence and characteristics of concurrent FD in addition to demographics, presenting complaints, and psychological comorbidities.

RESULTS

Among 308 patients presenting with refractory FC (average of 3.0 ± 2.3 constipation treatments tried unsuccessfully), 119 (38.6%) had concurrent FD. Aside from meeting FD criteria, the presence of concurrent FD was associated with patient complaints of esophageal symptoms (Odds ratio = 3.1; 95% confidence interval, 1.80-5.42) and bloating and distension (Odds ratio = 2.67; 95% confidence interval, 1.50-4.89). Patients with concurrent FD were more likely to have a history of an eating disorder (21.0% vs 12.7%) and were also more likely to present with current avoidant/restrictive food intake disorder-related symptoms (31.9% vs 21.7%).

CONCLUSION

Almost 40% of adult patients referred for refractory FC met criteria for concurrent FD in a tertiary-level cohort. The presence of both FC and FD was associated with greater esophageal symptoms and bloating/distention. Determining presence of concurrent FD may represent an additional therapeutic opportunity in refractory patients who may attribute symptoms to FC alone.

Clinical features of adult patients with avoidant/restrictive food intake disorder presenting for medical stabilization: A descriptive study

OBJECTIVE

The purpose of this study is to describe the clinical features of adult patients with avoidant/restrictive food intake disorder (ARFID) to better understand the medical findings, psychological comorbidities, and laboratory abnormalities in this population.

METHOD

We completed a retrospective chart review of all adult patients with a diagnosis of ARFID, admitted for medical stabilization, between April 2016 and June 2021, to an inpatient hospital unit, which specializes in severe eating disorders. Information collected included anthropomorphic data, laboratory assessments, and medical history at time of admission.

RESULTS

One hundred and twenty-two adult patients with ARFID were identified as meeting inclusion criteria for the study. The most common ARFID presentation was "fear of adverse consequences." The majority were female (70%), with an average age of 32.7 ± 13.7 years and mean percent of ideal body weight (m%IBW) of 68.2 ± 10.9. The most common laboratory abnormalities were low serum prealbumin and vitamin D, hypokalemia, leukopenia, and elevated serum bicarbonate. The most common psychiatric diagnoses were anxiety and depressive disorders, and the most common medical diagnoses were disorders of gut-brain interaction (DGBI).

DISCUSSION

This is the largest study to the authors' knowledge of medical presentations in adult patients with ARFID. Our results reflect that the adult patient with ARFID may, in some aspects, present differently than pediatric and adolescent patients with ARFID, or from ARFID patients requiring less intensive care. This study highlights the need for further investigation of adult patients with ARFID.

PUBLIC SIGNIFICANCE

ARFID is a restrictive eating disorder first defined in 2013. This study explores the medical presentations of adult patients (>18 years old) with ARFID presenting for specialized eating disorder treatment and identifies unique features of the adult presentation for treatment, compared to pediatric and adolescent peers.

Adaptive depends on context: An examination of the Intuitive Eating Scale-2 in an eating disorder sample

Though there is a robust literature base linking intuitive eating (IE) to better psychological health and reduced eating pathology, little is known about the psychometric properties of IES-2 measurement or how IE relates to eating psychopathology within eating disorder clinical samples. Importantly, some seemingly adaptive eating behaviors in non-clinical populations could conceivably result from disordered eating within clinical eating disorder populations (e.g., not eating when not hungry because of distorted hunger-fullness cues, furthering restriction). This study examined the factor structure, psychometric properties, and correlates of the Intuitive Eating Scale-2 (IES-2) in a transdiagnostic eating disorder sample (N = 224). Participants at an eating disorder specialty treatment center completed the IES-2 upon assessment, along with other symptomology measures. A confirmatory factor analysis was performed, finding a poor model fit in this transdiagnostic sample, CFI = 0.889, TLI = 0.869, RMSEA = 0.095, TLI = 0.869, and SRMR = 0.099. Through exploratory factor analysis, we identified a factor solution for the measure that can be used transdiagnostically in this population, with revised scoring and modifications. As expected, the IES-2 demonstrated construct validity, with higher IE being associated with lower eating pathology (r = -0.36, p < .01), lower clinical impairment (r = -0.26, p < .01), lower body image dissatisfaction (r = -0.39, p < .05), and lower depressive symptoms (r = -0.20, p < .01), supporting construct validity. As anticipated, IES-2 was not related to emotion regulation, supporting discriminant validity. This study suggests that the IES-2 does not perform as expected in a transdiagnostic clinical eating disorder population, and instead, a revised scored 21-item IES-2 is suggested, with interpretation of only the total score and two subscales.

Identification and Management of Eating Disorders (including ARFID) in GI Patients

Eating disorders are characterized by cognitions (eg, fear of gastrointestinal symptoms around eating, overvaluation of body shape/weight) and behaviors (eg, dietary restriction, binge eating) associated with medical (eg, weight loss), and/or psychosocial impairments (eg, high distress around eating). With growing evidence for bidirectional relationships between eating disorders and gastrointestinal disorders, gastroenterology providers' awareness of historical, concurrent, and potential risk for eating disorders is imperative. In this conceptual review, we highlight risk and maintenance pathways in the eating disorder-gastrointestinal disorder intersection, delineate different types of eating disorders, and provide recommendations for the gastroenterology provider in assessing and preventing eating disorder symptoms..

Elevated fullness and bloating as correlates of eating pathology: Implications for screening

A minority of individuals with eating disorders report being asked about their eating by health care professionals; delayed detection of eating disorders may contribute to poorer outcomes. The current study investigated common meal-related gastrointestinal symptoms (i.e., elevated fullness and bloating) as correlates of eating pathology that may be more readily disclosed to health professionals and indicate the need to assess for eating pathology. The current study also tested the hypothesis that elevated fullness and bloating are more strongly linked to eating pathology among those with higher body dissatisfaction. 281 university students (70.1% female, 84.3% white) completed gastrointestinal symptom and eating pathology assessments. Elevated fullness and bloating were each associated with increased purging, restrictive eating behaviors, and likelihood of having an eating disorder. Elevated fullness and bloating were more strongly linked to purging and probable eating disorder diagnosis with higher, relative to lower, body dissatisfaction. However, body dissatisfaction did not moderate the relationship between gastrointestinal symptoms and restrictive eating behaviors. Results indicate that elevated fullness and bloating are correlates of eating pathology. Healthcare professionals should consider and/or assess for eating pathology when elevated fullness and bloating are reported; further assessment of body dissatisfaction may be helpful in identifying purging behaviors.

British Society of Gastroenterology guidelines on the management of functional dyspepsia

Functional dyspepsia (FD) is a common disorder of gut-brain interaction, affecting approximately 7% of individuals in the community, with most patients managed in primary care. The last British Society of Gastroenterology (BSG) guideline for the management of dyspepsia was published in 1996. In the interim, substantial advances have been made in understanding the complex pathophysiology of FD, and there has been a considerable amount of new evidence published concerning its diagnosis and classification, with the advent of the Rome IV criteria, and management. The primary aim of this guideline, commissioned by the BSG, is to review and summarise the current evidence to inform and guide clinical practice, by providing a practical framework for evidence-based diagnosis and treatment of patients. The approach to investigating the patient presenting with dyspepsia is discussed, and efficacy of drugs in FD summarised based on evidence derived from a comprehensive search of the medical literature, which was used to inform an update of a series of pairwise and network meta-analyses. Specific recommendations have been made according to the Grading of Recommendations Assessment, Development and Evaluation system. These provide both the strength of the recommendations and the overall quality of evidence. Finally, in this guideline, we consider novel treatments that are in development, as well as highlighting areas of unmet need and priorities for future research.

Orthorexia nervosa is a concern in gastroenterology: A scoping review

There is concern that use of restrictive therapeutic diets, such as those used in disorders of the gut-brain interaction (DGBI), may increase disordered eating. In this issue of Neurogastroenterology and Motility, Burton Murray et al. and Peters et al. both demonstrate a high prevalence of disordered eating in patients with gastrointestinal conditions, particularly those with DGBI. Given these findings, it is likely that orthorexia is common in this patient group, although this was not directly examined in these studies. Orthorexia nervosa is described as an obsessive and unsafe focus on eating foods perceived as healthy. This mini-review therefore focuses on orthorexia by conducting a scoping review, as per the PRISMA extension for scoping reviews, aimed to assess the prevalence of orthorexia, and associations between orthorexia and restrictive eating practices. While a wide range of orthorexia prevalence has been reported (0%-97%) across the 57 studies included, no studies assessed prevalence specifically in gastrointestinal conditions. Four of eight studies describing diseases associated with specific dietary patterns suggested that participants who followed a diet for "digestive issues" or "food intolerances" were at higher orthorexia risk. These results suggest that dietary modifications may be a factor contributing to orthorexia. Additionally, we provide a commentary on the clinical implications of the findings for gastrointestinal conditions including a clinical flow chart. Clinicians should consider if a restrictive diet is appropriate for individuals with DGBI and include screening for disordered eating prior to implementation of dietary modifications. Future prospective studies should evaluate orthorexia within this patient group.

Irritable bowel syndrome: Factors of importance for disease-specific quality of life

BACKGROUND

Irritable bowel syndrome patients report reduced disease-specific quality of life (IBSQOL). Factors of potential relevance for QOL include gastrointestinal (GI), psychological, and somatic symptoms, demographics, and GI motor and sensory abnormalities.

OBJECTIVE

The aim of our study was to evaluate the relative importance of these factors on the different IBSQOL dimensions.

METHODS

We included irritable bowel syndrome (IBS) patients who completed validated questionnaires to assess QOL, stool form and frequency, GI symptom severity, psychological distress, GI-specific anxiety, sense of coherence, and overall somatic symptom severity. Patients also underwent tests for oroanal transit time and rectal sensitivity. The nine dimensions of IBSQOL and their average (overall IBSQOL) were used as outcome variables, and factors associated with these were assessed using general linear models.

RESULTS

We included 314 IBS patients (74% female, mean age 36.3 ± 12.2 years). Higher stool frequency, GI and overall somatic symptom severity, psychological distress, and GI-specific anxiety were independently associated with reduced overall IBSQOL, with the model explaining 60% of the variance (p < 0.001). In models using each of the nine dimensions as outcomes, different association of demographic factors, GI symptoms, overall somatic symptom severity, psychological factors and sense of coherence were associated with reduced IBSQOL, explaining 20%-60% of the variance, with GI-specific anxiety being the factor that contributed most frequently. Rectal sensitivity or oroanal transit time were not independently associated with any of the dimensions.

CONCLUSION

Different combinations of demographic factors, GI and somatic symptoms, and psychological factors are of importance for the nine IBSQOL dimensions. Gastrointestinal-specific anxiety was the most important factor contributing to the majority of those dimensions in patients with IBS.

Food Avoidance and Restriction in Irritable Bowel Syndrome: Relevance for Symptoms, Quality of Life and Nutrient Intake

BACKGROUND & AIMS

Neither food intake nor the clinical characteristics of irritable bowel syndrome (IBS) patients with severe food avoidance and restriction have been investigated. The aim of our study was to identify those patients and to characterize their symptoms, quality of life, and nutrient intake.

METHODS

IBS patients who completed the IBS Quality of Life Instrument (IBS-QOL) at our secondar and tertiary center were included. The 3 questions constituting the food domain were used to identify patients with reported severe food avoidance and restriction. The patients also completed validated questionnaires to assess stool form (Bristol Stool Form), gastrointestinal (GI) symptom severity (z score of IBS Severity Scoring System and Gastrointestinal Symptom Rating Scale-IBS), psychological distress (Hospital Anxiety and Depression Scale), GI-specific anxiety (Visceral Sensitivity Index), and somatic symptom severity (z score of Symptom Checklist-90-Revised and Patient Health Questionnaire-15). A 4-day food diary was used to analyze food intake in 246 patients.

RESULTS

We included 955 IBS patients (75 % women; mean age 38.3 ± 13.3 years). In total, 13.2 % of the patients reported severe food avoidance and restriction, and in these patients all aspects of quality of life were lower (P < .01) and psychological, GI, and somatic symptoms were more severe (P < .05). Reported severe food avoidance and restriction was associated with lower total energy intake (P = .002) and lower intake of protein (P = .001) and carbohydrates (P = .005). In a logistic regression analysis, loose stools were found to be independently associated with reported severe food avoidance and restriction (R² = 0.062).

CONCLUSIONS

IBS patients with severe food avoidance and restriction constitute a subgroup with more severe symptoms overall, reduced quality of life, and reduced intake of nutrients. This needs to be acknowledged in the clinical management of these patients.

Prevalence and Characteristics of Avoidant/Restrictive Food Intake Disorder in Pediatric Neurogastroenterology Patients

ABSTRACT

Recent reports document avoidant/restrictive food intake disorder (ARFID) symptoms among 13-40% of adults presenting to neurogastroenterology clinics, but ARFID in pediatrics is understudied. We conducted a retrospective review of charts from 129 consecutive referrals (ages 6-18 years; 57% female) for pediatric neurogastroenterology examination, from January 2016 through December 2018. Eleven cases (8%) met the full criteria for ARFID by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition and 19 cases (15%) had clinically significant avoidant/ restrictive eating behaviors with insufficient information for a definitive ARFID diagnosis. Of patients with ARFID symptoms (n = 30), 20 (67%) cited fear of gastrointestinal symptoms as motivation for their avoidant/ restrictive eating. Compared to patients without ARFID symptoms, patients with ARFID symptoms were older (P  < .001), more likely to be female (51% vs 79%, P  = 0.014), and more frequently presented with eating/weight-related complaints (15% vs 33%, P  = 0.026). This pilot retrospective study showed ARFID symptoms present in 23% of pediatric neurogastroenterology patients; further research is needed to understand risk and maintenance factors of ARFID in the neurogastroenterology setting.

Pediatric Avoidant-Restrictive Food Intake Disorder and gastrointestinal-related Somatic Symptom Disorders: Overlap in clinical presentation

Certain presentations of Avoidant/Restrictive Food Intake Disorder (ARFID) and Somatic Symptom and Related Disorders (SSRDs) have conceptual overlap, namely, distress and impairment related to a physical symptom. This study compared characteristics of pediatric patients diagnosed with ARFID to those with gastrointestinal (GI)-related SSRD. A 5-year retrospective chart review at a tertiary care pediatric hospital comparing assessment data of patients with a diagnosis of ARFID (n = 62; 69% girls, M_age = 14.08 years) or a GI-related SSRD (n = 37; 68% girls, M_age = 14.25 years). Patients diagnosed with ARFID had a significantly lower percentage of median BMI than those with GI-related SSRD. Patients diagnosed with ARFID were most often assessed in the Eating Disorders Program, whereas patients diagnosed with an SSRD were most often assessed by Consultation-Liaison Psychiatry. Groups did not differ on demographics, psychiatric diagnoses, illness duration, or pre-assessment services/medications. GI symptoms were common across groups. Patients diagnosed with an SSRD had more co-occurring medical diagnoses. A subset (16%) of patients reported symptoms consistent with both diagnoses. Overlap is observed in the clinical presentation of pediatric patients diagnosed with ARFID or GI-related SSRD. Some group differences emerged, including anthropometric measurements and co-occurring medical conditions. Findings may inform diagnostic classification and treatment approach.

Novel Advances in the Evaluation and Treatment of Children With Symptoms of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease has long been implicated as a cause for multiple pediatric symptoms ranging from abdominal pain and regurgitation to cough and dental erosions. Diagnostic testing has evolved greatly over the last 20 years; initial testing with pH-metry to measure esophageal acid reflux burden has evolved into measurement of both acid and non-acid reflux and liquid and gas reflux. However, measuring reflux burden alone only tells a small part of the GERD story and many symptoms originally thought to be reflux related are, in fact, related to other disorder which mimic reflux. The current paradigm which involves empiric treatment of symptoms with acid suppression has been replaced with early testing for not only gastroesophageal reflux but also for other diagnostic masqueraders. The focus for interventions has shifted away from acid suppression toward motility interventions and includes a greater recognition of both functional and motility disorders which present with reflux symptoms.

Validation of the nine item ARFID screen (NIAS) subscales for distinguishing ARFID presentations and screening for ARFID

OBJECTIVE

The Nine Item Avoidant/Restrictive Food Intake Disorder (ARFID) Screen (NIAS) has three subscales aligned with ARFID presentations but clinically validated cutoff scores have not been identified. We aimed to examine NIAS subscale (picky eating, appetite, fear) validity to: (1) capture clinically-diagnosed ARFID presentations; (2) differentiate ARFID from other eating disorders (other-ED); and (3) capture ARFID symptoms among individuals with ARFID, individuals with other-ED, and nonclinical participants.

METHOD

Participants included outpatients (ages 10-76 years; 75% female) diagnosed with ARFID (n = 49) or other-ED (n = 77), and nonclinical participants (ages 22-68 years; 38% female, n = 40). We evaluated criterion-related concurrent validity by conducting receiver operating curve (ROC) analyses to identify potential subscale cutoffs and by testing if cutoffs could capture ARFID with and without use of the Eating Disorder Examination-Questionnaire (EDE-Q).

RESULTS

Each NIAS subscale had high AUC for capturing those who fit versus do not fit each ARFID presentation, resulting in proposed cutoffs of ≥10 (sensitivity = .97, specificity = .63), ≥9 (sensitivity = .86, specificity = .70), and ≥ 10 (sensitivity = .68, specificity = .89) on the NIAS-picky eating, NIAS-appetite, and NIAS-fear subscales, respectively. ARFID versus other-ED had high AUC on the NIAS-picky eating (≥10 proposed cutoff), but not NIAS-appetite or NIAS-fear subscales. NIAS subscale cutoffs had a high association with ARFID diagnosis, but only correctly classified other-ED in combination with EDE-Q Global <2.3.

DISCUSSION

To screen for ARFID, we recommend using a screening tool for other-ED (e.g., EDE-Q) in combination with a positive score on any NIAS subscale (i.e., ≥10, ≥9, and/or ≥10 on the NIAS-picky eating, NIAS-appetite, and NIAS-fear subscales, respectively).

Gastrointestinal symptoms from an epidemiological perspective

Four manuscripts on gastro-intestinal problems or disorders of gut-brain interaction are discussed from an epidemiological perspective. A literature review with strict inclusion criteria pointed out the dearth of evidence-based knowledge on gastrointestinal symptoms following treatment for anorexia nervosa. An epidemiological follow-up study showing the relevance of childhood abdominal pain for fasting to control weight in adolescence is used to emphasize the need to refine our approach to risk factor research in eating disorders. Two additional studies highlight the high prevalence of gastro-intestinal problems in eating disorders underscoring a need for improved consideration of these symptoms in clinical practice and eating disorder research.

Brain-gut psychotherapies: Promising tools to address gastrointestinal problems in patients with eating disorders

Gastrointestinal (GI) problems are common in individuals with eating disorders (EDs) and associated with distress, impairment, and increased healthcare utilization. GI symptoms may be exacerbated by meals and other interventions central to ED recovery thereby contributing to negative clinical outcomes. Informed by models emphasizing the role of the brain-gut axis in the expression of GI symptoms, this article describes a program of research to adapt "brain-gut psychotherapies" for EDs. First, the role of the brain-gut axis in GI symptoms is described, and evidence-based brain-gut psychotherapies are reviewed, with an emphasis on cognitive behavioral therapy for GI disorders and gut-directed hypnotherapy. Next, future directions for research in EDs to (a) understand the impact of GI symptoms on illness course and outcome; (b) clarify target engagement; (c) evaluate brain-gut psychotherapies; and (d) optimize intervention reach and delivery are described. We present a conceptual model that emphasizes GI-specific anxiety and altered gut physiology as targets of brain-gut psychotherapies in EDs, and discuss several issues that need to be addressed in designing clinical trials to test these interventions. We also describe how engagement with multidisciplinary stakeholders and use of digital tools could speed translation from the laboratory to clinical settings.

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.

What Are the Pearls and Pitfalls of the Dietary Management for Chronic Diarrhoea?

Chronic diarrhoea affects up to 14% of adults, it impacts on quality of life and its cause can be variable. Patients with chronic diarrhoea are presented with a plethora of dietary recommendations, often sought from the internet or provided by those who are untrained or inexperienced. In this review, we summarise the possible causes of chronic diarrhoea that can be managed by diet, the symptom improvement and quality of life benefits but also the potential risks of such dietary treatments. Clinicians need to consider both the benefits and risks of dietary treatments before making dietary recommendations to manage chronic diarrhoea. The pivotal role that dietitians have in ensuring optimal symptom improvement without jeopardising nutritional and overall health is discussed.