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

A Role for the Microbiota-Gut-Brain Axis in Avoidant/Restrictive Food Intake Disorder: A New Conceptual Model

OBJECTIVE

Avoidant/restrictive food intake disorder (ARFID) is an eating disorder characterized by a severely restrictive diet leading to significant physical and/or psychosocial sequelae. Largely owing to the phenotypic heterogeneity, the underlying pathophysiological mechanisms are relatively unknown. Recently, the communication between microorganisms within the gastrointestinal tract and the brain-the so-called microbiota-gut-brain axis-has been implicated in the pathophysiology of eating disorders. This Spotlight review sought to investigate and conceptualize the possible ways that the microbiota-gut-brain axis is involved in ARFID to drive future research in this area.

METHOD

By relating core symptoms of ARFID to gut microbiota and its signaling pathways to the brain, we evaluated how the gut microbiota is potentially involved in the pathophysiology of ARFID.

RESULTS

We hypothesized that the restricted type and amount of food intake characteristic of ARFID diminishes gut microbial diversity, including beneficial bacteria and their metabolites capable of signaling to the brain, to modulate biopsychological pathways relevant to ARFID: homeostatic signaling, food reward, interoception, sensory sensitivity, disgust, perseveration, fear-based learning, and mood. Candidate signaling mechanisms include microbial-induced effects on inflammation, cortisol, and neurotransmitters such as dopamine and serotonin.

DISCUSSION

Through reviewing the extant evidence, we conceptualized a new theoretical framework of ARFID with an emphasis on microbiota-gut-brain axis signaling to inform future research. Although more research is necessary to evaluate this theoretical model, the tentative evidence suggests that therapeutics specifically targeting the gut microbiota for the treatment of ARFID symptomatology warrants more investigation.

Eating concerns in youth with functional abdominal pain disorders

OBJECTIVES

Adolescents with functional abdominal pain (FAP) often experience pain and other gastrointestinal symptoms in the context of eating, which may place them at risk for eating disorders. This study compared disordered eating and its sequalae in adolescents with FAP to those with chronic headache.

METHODS

Participants in this retrospective chart review study were 270 adolescents and young adults (mean age 15.9; standard deviation [SD] = 1.63; 60% female) attending an intensive, interdisciplinary pain treatment program, including 135 youth with FAP and an age- and gender-matched control group with a primary pain diagnosis of chronic headache. Information was extracted related to eating- and weight-related symptoms.

RESULTS

Independent t-tests and χ2 analyses found that compared with adolescents with chronic headache, patients with FAP showed significantly more eating pathology as reflected by scores on the Eating Attitudes Test-26 (EAT-26) (p < 0.001), endorsement of pain-related restrictive eating (p < 0.01), eating disorder history (p < 0.001), and avoidant restrictive food intake disorder (ARFID) diagnoses (p < 0.001). Compared to those with chronic headache, significantly more patients with FAP had lost 10 pounds or more (p < 0.01) and a higher proportion were underweight (p < 0.001). Among all participants, a history of exclusion diets used to manage symptoms significantly increased the risk for ARFID (p < 0.001).

CONCLUSION

The results of this study highlight the increased risk of eating-related concerns among youth with FAP, as well as the judicious use of exclusion diets to manage symptoms in these patients.

Irritable bowel syndrome: When food is a pain in the gut

Irritable bowel syndrome (IBS) is a chronic gastrointestinal condition associated with altered bowel habits and recurrent abdominal pain, often triggered by food intake. Current treatments focus on improving stool pattern, but effective treatments for pain in IBS are still lacking due to our limited understanding of pathophysiological mechanisms. Visceral hypersensitivity (VHS), or abnormal visceral pain perception, underlies abdominal pain development in IBS, and mast cell activation has been shown to play an important role in the development of VHS. Our work recently revealed that abdominal pain in response to food intake is induced by the sensitization of colonic pain-sensing neurons by histamine produced by activated mast cells following a local IgE response to food. In this review, we summarize the current knowledge on abdominal pain and VHS pathophysiology in IBS, we outline the work leading to the discovery of the role of histamine in abdominal pain, and we introduce antihistamines as a novel treatment option to manage chronic abdominal pain in patients with IBS.

Avoiding the use of long-term parenteral support in patients without intestinal failure: A position paper from the European Society of Clinical Nutrition & Metabolism, the European Society of Neurogastroenterology and Motility and the Rome Foundation for Disorders of Gut-Brain Interaction

The role of long-term parenteral support in patients with underlying benign conditions who do not have intestinal failure (IF) is contentious, not least since there are clear benefits in utilising the oral or enteral route for nutritional support. Furthermore, the risks of long-term home parenteral nutrition (HPN) are significant, with significant impacts on morbidity and mortality. There has, however, been a recent upsurge of the use of HPN in patients with conditions such as gastro-intestinal neuromuscular disorders, opioid bowel dysfunction, disorders of gut-brain interaction and possibly eating disorders, who do not have IF. As a result, the European Society of Clinical Nutrition and Metabolism (ESPEN), the European Society of Neuro-gastroenterology and Motility (ESNM) and the Rome Foundation for Disorders of Gut Brain Interaction felt that a position statement is required to clarify - and hopefully reduce the potential for harm associated with - the use of long-term parenteral support in patients without IF. Consensus opinion is that HPN should not be prescribed for patients without IF, where the oral and/or enteral route can be utilised. On the rare occasions that PN commencement is required to treat life-threatening malnutrition in conditions such as those listed above, it should only be prescribed for a time-limited period to achieve nutritional safety, while the wider multi-disciplinary team focus on more appropriate biopsychosocial holistic and rehabilitative approaches to manage the patient's primary underlying condition.

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.

Lactose malabsorption and intolerance in older adults

PURPOSE OF REVIEW

Lactose malabsorption and intolerance are very common conditions. However, their optimal approach, including the diagnostic assessment, remains a matter of debate, especially in advanced age. In this brief review, we focused on current knowledge, concerns, and impact in clinical practice of lactose malabsorption and intolerance in elderly.

RECENT FINDINGS

Older adults are at high risk of malnutrition, owing to frequent occurrence of cognitive impairment, loss of appetite, dysphagia, and poor oral health. A significant decrease in the consumption of dairy products may lead to inadequate intake of high-quality protein and minerals, with a consequent impact on muscle and bone health. Testing for lactose malabsorption may be challenging in older adults, if not useless. Instead, a detailed clinical evaluation should always be pursued to identify both lactose intolerance and all confounding factors mimicking the same clinical picture.

SUMMARY

The management of lactose malabsorption and intolerance in older adults deserves a personalized approach. Because of the importance of maintaining an adequate nutritional status in this age group, efforts should be put forth to avoid excessively restrictive diets.

Latent profile analysis reveals the central role of psychological symptoms in driving disease severity in chronic constipation

BACKGROUND

Chronic constipation (CC) is defined by symptom criteria reflecting heterogenous physiology. However, many patients with CC have significant psychological comorbidities-an alternative definition using a biopsychosocial classification model could be warranted to inform future treatments. We sought to: (1) empirically derive psychological symptom profiles of patients with CC using latent profile analysis and (2) validate these profiles by comparing them on symptom severity, GI-specific anxiety, body mass index (BMI), and anorectal manometry findings.

METHODS

Participants included adults presenting for anorectal manometry for CC (N = 468, 82% female, Mage = 47). Depression/anxiety symptoms and eating disorder (ED) symptoms (EAT-26) were used as indicators (i.e., variables used to derive profiles) representing unique psychological constructs. Constipation symptoms, GI-specific anxiety, BMI, and anorectal manometry results were used as validators (i.e., variables used to examine the clinical utility of the resulting profiles).

KEY RESULTS

A 5-profile solution provided the best statistical fit, comprising the following latent profiles (LPs): LP1 termed "high dieting, low bulimia;" LP2 termed "high ED symptoms;" LP3 termed "moderate ED symptoms;" LP4 termed "high anxiety and depression, low ED symptoms;" and LP5 termed "low psychological symptoms." The low psychological symptom profile (61% of the sample) had lower abdominal and overall constipation severity and lower GI-specific anxiety compared to the four profiles characterized by higher psychological symptoms (of any type). Profiles did not significantly differ on BMI or anorectal manometry results.

CONCLUSIONS AND INFERENCES

Profiles with high psychological symptoms had increased constipation symptom severity and GI-specific anxiety in adults with CC. Future research should test whether these profiles predict differential treatment outcomes.

Avoidant/restrictive food intake disorder prevalence is high in children with gastroparesis and functional dyspepsia

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) prevalence in children with gastroparesis (Gp) and/or functional dyspepsia (FD) is unknown. We aimed to identify ARFID prevalence and trajectory over 2 months in children with Gp, FD, and healthy children (HC) using two screening questionnaires. We also explored the frequency of a positive ARFID screen between those with/without delayed gastric emptying or abnormal fundic accommodation.

METHODS

In this prospective longitudinal study conducted at an urban tertiary care hospital, patients ages 10-17 years with Gp or FD and age- and gender-matched HC completed two validated ARFID screening tools at baseline and 2-month follow-up: the Nine Item ARFID Screen (NIAS) and the Pica, ARFID, and Rumination Disorder Interview-ARFID Questionnaire (PARDI-AR-Q). Gastric retention and fundic accommodation (for Gp and FD) were determined from gastric emptying scintigraphy.

KEY RESULTS

At baseline, the proportion of children screening positive for ARFID on the NIAS versus PARDI-AR-Q was Gp: 48.5% versus 63.6%, FD: 66.7% versus 65.2%, HC: 15.3% versus 9.7%, respectively; p < 0.0001 across groups. Of children who screened positive at baseline and participated in the follow-up, 71.9% and 53.3% were positive 2 months later (NIAS versus PARDI-AR-Q, respectively). A positive ARFID screen in Gp or FD was not related to the presence/absence of delayed gastric retention or abnormal fundic accommodation.

CONCLUSIONS & INFERENCES

ARFID detected from screening questionnaires is highly prevalent among children with Gp and FD and persists for at least 2 months in a substantial proportion of children. Children with these disorders should be screened for ARFID.

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.

Co-existing mental and somatic conditions in Swedish children with the avoidant restrictive food intake disorder phenotype

Background

Avoidant restrictive food intake disorder (ARFID) is a feeding and eating disorder, characterized by limited variety and/or quantity of food intake impacting physical health and psychosocial functioning. Children with ARFID often present with a range of psychiatric and somatic symptoms, and therefore consult various pediatric subspecialties; large-scale studies mapping comorbidities are however lacking. To characterize health care needs of people with ARFID, we systematically investigated ARFID-related mental and somatic conditions in 616 children with ARFID and >30,000 children without ARFID.

Methods

In a Swedish twin cohort, we identified the ARFID phenotype in 6-12-year-old children based on parent-reports and register data. From >1,000 diagnostic ICD-codes, we specified mental and somatic conditions within/across ICD-chapters, number of distinct per-person diagnoses, and inpatient treatment days between birth and 18th birthday (90 outcomes). Hazard ratios (HR) and incidence rate ratios (IRR) were calculated.

Findings

Relative risks of neurodevelopmental, gastrointestinal, endocrine/metabolic, respiratory, neurological, and allergic disorders were substantially increased in ARFID (e.g., autism HR[CI95%]=9.7[7.5-12.5], intellectual disability 10.3[7.6-13.9], gastroesophageal reflux disease 6.7[4.6-9.9], pituitary conditions 5.6[2.7-11.3], chronic lower respiratory diseases 4.9[2.4-10.1], epilepsy 5.8[4.1-8.2]). ARFID was not associated with elevated risks of autoimmune illnesses and obsessive-compulsive disorder. Children with ARFID had a significantly higher number of distinct mental diagnoses (IRR[CI95%]=4.7[4.0-5.4]) and longer duration of hospitalizations (IRR[CI95%]=5.5[1.7-17.6]) compared with children without ARFID. Children with ARFID were diagnosed earlier with a mental condition than children without ARFID. No sex-specific differences emerged.

Interpretation

This study yields the broadest and most detailed evidence of co-existing mental and somatic conditions in the largest sample of children with ARFID to date. Findings suggest a complex pattern of health needs in youth with ARFID, underscoring the critical importance of attention to the illness across all pediatric specialties.

Funding

Fredrik and Ingrid Thurings Foundation, Mental Health Foundation.