An update on gastrointestinal disturbances in eating disorders

Clinical characterization of Co-morbid autoimmune disease and eating disorders: a retrospective chart review

Research suggests a link between autoimmune illnesses (AI) and eating disorders (ED). We retrospectively reviewed charts of adolescent patients presenting for eating disorder treatment. We compared the presentation and treatment course for those with an ED and comorbid AI [with (GI-AI, N = 59) or without (non-GI, N = 21) gastrointestinal inflammation] with matched ED-only cases. The sample was overwhelmingly female, with an average age of 15.40. Weight gain trajectories differed across groups, with similar rates of weight gain between controls and non GI-AI cases and with a lower rate of weight gain for individuals with comorbid GI-AI. Over half (56%) of patients reported an AI diagnosis prior to ED; 38% reported an AI diagnosis following ED, and 6% reported ED and AI simultaneous diagnosis. On presentation, ED-only controls had higher rates of comorbid anxiety than cases in either AI group, while those with non-GI AI were more likely to report depression. Mean total GI symptoms, % goal weight at presentation, vital sign instability, and markers of refeeding syndrome did not differ across groups. Health care professionals treating patients with either condition should have a low threshold for asking additional questions to identify the presence of the other condition.

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.

Binge-Spectrum Eating Disorders, Mood, and Food Insecurity in Young Adults With Obesity

BACKGROUND

Disordered eating is common but underrecognized in people with obesity and the relationship of food insecurity, mood, and binge-spectrum eating disorders has not been well addressed in samples with higher weight. Young adults are particularly vulnerable to developing disordered eating.

AIM

The purpose of this study was to compare the prevalence of food insecurity, depressive symptoms, anxiety, and loneliness among young adults (aged 18-35 years) who screened positive for binge-spectrum eating disorders (i.e., binge eating disorder and bulimia nervosa), those with subthreshold forms of these disorders, and individuals who did not screen positive for these conditions.

METHOD

This was a cross-sectional study of young adults with a self-reported body mass index ≥30 kg/m2 from the United States who were recruited online. Participants (N = 1,331; M ± SD age = 28.0 ± 3.4 years; body mass index [BMI] = 36.5 ± 6.2 kg/m2; 73.9% male; 56.3% White) completed surveys that evaluated disordered eating behaviors, food insecurity, mood, and lifestyle factors.

RESULTS

In the sample, 8.0% of participants screened positive for binge-spectrum eating disorder and 16.0% had probable subthreshold symptoms. Higher depressive symptoms (odds ratio [OR] = 1.11, 95% confidence interval [CI] = [1.03, 1.20], p = .01), perceived stress (OR = 1.13, 95% CI = [1.07, 1.19], p < .001), and food insecurity scores (OR = 1.12, 95% CI = [1.03, 1.21], p = .01) were associated with an increased likelihood of threshold binge-spectrum eating disorders.

CONCLUSION

People with disordered eating should also be evaluated for mood disorders and food insecurity and vice versa. Further research is needed to evaluate interventions that address food insecurity and mood disorders, which may help to decrease disordered eating.

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.

Microbiota in anorexia nervosa: potential for treatment

Anorexia nervosa (AN) is characterised by the restriction of energy intake in relation to energy needs and a significantly lowered body weight than normally expected, coupled with an intense fear of gaining weight. Treatment of AN is currently based on psychological and refeeding approaches, but their efficacy remains limited since 40% of patients after 10 years of medical care still present symptoms of AN. The intestine hosts a large community of microorganisms, called the "microbiota", which live in symbiosis with the human host. The gut microbiota of a healthy human is dominated by bacteria from two phyla: Firmicutes and, majorly, Bacteroidetes. However, the proportion in their representation differs on an individual basis and depends on many external factors including medical treatment, geographical location and hereditary, immunological and lifestyle factors. Drastic changes in dietary intake may profoundly impact the composition of the gut microbiota, and the resulting dysbiosis may play a part in the onset and/or maintenance of comorbidities associated with AN, such as gastrointestinal disorders, anxiety and depression, as well as appetite dysregulation. Furthermore, studies have reported the presence of atypical intestinal microbial composition in patients with AN compared with healthy normal-weight controls. This review addresses the current knowledge about the role of the gut microbiota in the pathogenesis and treatment of AN. The review also focuses on the bidirectional interaction between the gastrointestinal tract and the central nervous system (microbiota-gut-brain axis), considering the potential use of the gut microbiota manipulation in the prevention and treatment of AN.

Gut-Brain Interaction Disorders and Anorexia Nervosa: Psychopathological Asset, Disgust, and Gastrointestinal Symptoms

BACKGROUND

Gastrointestinal (GI) symptoms are very common in subjects with eating disorders (EDs). This study aimed to (a) investigate the prevalence of gut-brain interaction disorders (DGBIs) in anorexia nervosa (AN) patients, according to ROME IV criteria; and (b) explore AN psychopathological assets and disgust that might impact GI symptoms.

METHODS

Thirty-eight female patients consecutively diagnosed with untreated AN (age 19.32 ± 5.59) in an outpatient clinic devoted to EDs underwent Eating Disorder Inventory-3 (EDI-3), Hospital Anxiety and Depression Scale (HADS), Social Phobia Anxiety Scale (SPAS), Body Uneasiness Test (BUT), and Disgust Scale (DS) questionnaires. The presence of DGBIs was evaluated and GI symptoms were assessed using a standardized intensity-frequency questionnaire.

RESULTS

A total of 94.7% of our sample met the diagnostic criteria for functional dyspepsia (FD), of which 88.8% presented the postprandial distress syndrome (PDS) subtype and 41.6% presented the epigastric pain syndrome (EPS) subtype. In addition, 52.6% of the sample met the diagnostic criteria for irritable bowel syndrome (IBS), while for functional constipation (FC), prevalence reached 7.9%. All participants presented a pathological score on the disgust scale. Significant correlations were found between several GI symptoms and psychopathological asset and disgust.

CONCLUSIONS

AN is a multifactorial disorder. It is necessary to implement studies with an integrated approach, taking into account DGBIs, as well as to monitor the emotional-cognitive structure that acts as a factor in maintaining the disorder.

Low Self-Esteem and Life Satisfaction as a Significant Risk Factor for Eating Disorders among Adolescents

Background: Eating disorders are a problem that is becoming more and more common among younger and younger age groups. Many studies examine the risk factors for EDs, however, the treatment of these diseases is very complicated and requires dietary, psychological and medical intervention. Methods: 233 primary and secondary school students aged 12 to 19 were surveyed using the EAT-26 (Eating Attitudes Test-26) questionnaire, the self-esteem Scale SES and the Cantril scale for life satisfaction. Results: Women, when compared to men, showed lower self-esteem, satisfaction with their appearance, body weight and their lives and at the same time a higher risk of eating disorders in all three areas. Low life satisfaction is often correlated with weight loss greater than 10 kg. Low self-esteem correlated positively with significant weight loss (>10 kg) and more frequent uncontrollable binge eating and exercising (more than 60 min a day) to influence appearance. People with low self-esteem were more likely to be treated for EDs. Subjects dissatisfied with their lives binged, feeling that they could not stop. Conclusion: The younger the person, the more likely they are to develop eating disorders. This is closely correlated with low self-esteem and negative life satisfaction. Men were more likely to be satisfied with their weight, appearance, and life, and were less likely to show ED symptoms.

Are the Effects of Malnutrition on the Gut Microbiota–Brain Axis the Core Pathologies of Anorexia Nervosa?

Anorexia nervosa (AN) is a disabling, costly, and potentially deadly illness. Treatment failure and relapse after treatment are common. Several studies have indicated the involvement of the gut microbiota–brain (GMB) axis. This narrative review hypothesizes that AN is driven by malnutrition-induced alterations in the GMB axis in susceptible individuals. According to this hypothesis, initial weight loss can voluntarily occur through dieting or be caused by somatic or psychiatric diseases. Malnutrition-induced alterations in gut microbiota may increase the sensitivity to anxiety-inducing gastrointestinal hormones released during meals, one of which is cholecystokinin (CCK). The experimental injection of a high dose of its CCK-4 fragment in healthy individuals induces panic attacks, probably via the stimulation of CCK receptors in the brain. Such meal-related anxiety attacks may take part in developing the clinical picture of AN. Malnutrition may also cause increased effects from appetite-reducing hormones that also seem to have roles in AN development and maintenance. The scientific background, including clinical, microbiological, and biochemical factors, of AN is discussed. A novel model for AN development and maintenance in accordance with this hypothesis is presented. Suggestions for future research are also provided.

Investigating service users' perspectives of eating disorder services: A meta-synthesis

OBJECTIVE

Despite a number of qualitative studies published from the perspective of eating disorder (ED) service users, there has been no attempt to exclusively synthesize their views to gain a fuller understanding of their ED service experiences. It is important to understand this perspective, since previous research highlights the difficulties ED healthcare professionals report when working with this client group.

METHOD

A systematic search of the literature was conducted to identify qualitative studies focusing on experiences of ED services from the perspective of service users. Twenty-two studies met the inclusion criteria and underwent a quality appraisal check using the Critical Appraisal Skills Programme (CASP) tool for qualitative research. These were then synthesized using a meta-synthesis approach.

RESULTS

Four overarching themes were generated: "Treatment: Focus on physical vs. psychological symptoms"; "Service Environment: The role of control within services"; "Staff: Experiences with staff and the value of rapport"; and "Peer Influence: Camaraderie vs. comparison." Service users expressed a desire for more psychological input to tackle underlying difficulties relating to their ED. A complex relationship with feelings of control was described, with some feeling over-controlled by service providers, while others retrospectively recognized the need for control to be taken away. Staff values, knowledge and trust played a significant role in treatment and recovery. Peers with an ED were described to be a valuable source of understanding and empathy, but some found peer influence to perpetuate comparison and competitiveness.

DISCUSSION

The results portray some of the conflicts and complexities that service users encounter in ED services. A running thread throughout is the perceived importance of adopting an individualized approach within these services.

Anorexia nervosa: Outpatient treatment and medical management

Anorexia nervosa (AN) is a disabling, costly and potentially deadly illness. Treatment failure and relapse are common after completing treatment, and a substantial proportion of patients develop severe and enduring AN. The time from AN debut to the treatment initiation is normally unreasonably long. Over the past 20 years there has been empirical support for the efficacy of several treatments for AN. Moreover, outpatient treatment with family-based therapy or individual psychotherapy is associated with good outcomes for a substantial proportion of patients. Early intervention improves outcomes and should be a priority for all patients. Outpatient treatment is usually the best format for early intervention, and it has been demonstrated that even patients with severe or extreme AN can be treated as outpatients if they are medically stable. Inpatient care is more disruptive, more costly, and usually has a longer waiting list than does outpatient care. The decision as to whether to proceed with outpatient treatment or to transfer the patient for inpatient therapy may be difficult. The core aim of this opinion review is to provide the knowledge base needed for performing safe outpatient treatment of AN. The scientific essentials for outpatient treatment are described, including how to assess and manage the medical risks of AN and how to decide when transition to inpatient care is indicated. The following aspects are discussed: early intervention, outpatient treatment of AN, including outpatient psychotherapy for severe and extreme AN, how to determine when outpatient treatment is safe, and when transfer to inpatient healthcare is indicated. Emerging treatments, ethical issues and outstanding research questions are also addressed.

Gastrointestinal complaints in patients with anorexia nervosa in the timecourse of inpatient treatment

BACKGROUND

In patients with anorexia nervosa (AN), gastrointestinal (GI) symptoms are common and usually improve during or after nutritional rehabilitation. It is unclear when exactly GI symptoms change in the timecourse of treatment and to which extent. In this study, we analyzed the timecourse of GI symptoms and their relation to disease-specific, demographic, anthropometric, and psychological factors in inpatients with AN.

METHODS

In weekly intervals, the Gastrointestinal Symptom Rating Scale (GSRS) was completed, and body weight was measured over a mean of 9.5 weeks in inpatients with AN. A total of four self-report questionnaires assessing psychological factors were completed before and after inpatient treatment. Data from 38 inpatients with AN were analyzed using mixed linear models.

RESULTS

Abdominal pain and constipation improved significantly in the timecourse with 0.085 (p = 0.002) and 0.101 (p = 0.004) points per week on the GSRS and were predicted to normalize after 13 (p = 0.002) and 17 (p = 0.004) weeks, respectively. Total GI symptoms tended to normalize after 25 weeks (p = 0.079). Indigestion (borborygmus, abdominal distension, eructation, flatulence) was the most severely pathological symptom at admission and did not improve significantly (p = 0.197). Diarrhea and reflux were, on average, not pathological at admission and remained stable during treatment. In addition to treatment time, the strongest predictors were ED pathology at admission for the development of abdominal pain, constipation, reflux, and total GI symptoms; stress for the development of constipation and total GI symptoms; and depression for constipation.

CONCLUSIONS

Informing patients with AN about the course of GI symptoms and their improvement during weight rehabilitation may help support compliance during treatment.

Findings from a web content analysis of resources targeting sporting coaches aimed at educating or upskilling on eating disorders and disordered eating in athletes

BACKGROUND

Eating disorders (ED) and disordered eating (DE) are highly prevalent in athletes. Coaches can play a role in the prevention of EDs and DE behaviours and are well placed to support athletes with an ED. However, coaches feel under-qualified and lack time and resources for supporting athletes and it is unclear the quality of training and resources available to upskill coaches in this space. Therefore, a web-based content analysis was undertaken to determine the type and source of online education resources currently available to coaches to help identify, prevent, manage and refer on for ED/DE behaviours.

METHODS

Three major search engines were searched using a combination of the following terms: (1) DE or ED resource and (2) coaches or sport. Included websites were specific for DE/EDs in athletes; targeted at coaches or sporting organisations; written in the English language; and published by a reputable site.

RESULTS

Twenty four out of 600 websites met inclusion criteria. The main reasons for exclusion were irreputable sites and websites not targeting coaches. The majority of included webpages were from professional bodies (n = 17) and targeted coaches (n = 24) and sporting organisations (n = 15), with an average quality rating of 4.2 out of 6. All websites provided educational resources but none provided official training. The most common topics discussed on these websites was ED/DE signs and symptoms (n = 17), and the effects of ED/DE on performance, mental and physical health (n = 11).

CONCLUSION

Few reputable online resources were identified in the current review. There is a need for more comprehensive education and training resources aimed at coaches and athletic organisations to help prevent, identify, manage and refer on for ED/DE behaviours.

Anorexia nervosa and inflammatory bowel diseases-Diagnostic and genetic associations

Background

Anorexia nervosa (AN), a serious eating disorder, and inflammatory bowel diseases (IBD) share a number of key symptoms, for example, discomfort during eating and early satiety. Despite the symptom overlap, studies on comorbidity are limited and mostly conducted in relatively small samples. This study investigates the comorbidity of diagnosed AN with IBD, and the subtypes Crohn's disease and ulcerative colitis, in a population-based sample and explores whether genetic factors could play a role in the overlap.

Methods

The study included 1,238,813 individuals born in Denmark 1981-2005 selected from the population register (5067 diagnosed with AN and 6947 diagnosed with any IBD), including a subsample of 23,236 individuals with genetic information (4271 with AN and 176 with any IBD). By combining hospital-based diagnoses recorded in health registers until 2013 with polygenic scores (PGS) of AN and IBD, we investigated possible associations between diagnoses of each disorder, both within individuals and families, and between PGS of one disorder and diagnosis of the other disorder. Analyses were conducted using Cox regression and logistic regression.

Results

We found that a prior diagnosis of AN was associated with hazard ratios of 1.44 (1.05, 1.97) for any IBD, 1.60 (1.04, 2.46) for Crohn's disease, and 1.66 (1.15, 2.39) for ulcerative colitis, whereas IBD diagnoses were not significantly associated with later AN diagnosis. No significant within-families associations were observed. We found no associations between AN and IBD using PGS.

Conclusions

AN was associated with later risk of IBD, Crohn's disease, and ulcerative colitis; however, the reverse was not observed. It is important for clinicians to be aware of this association to evaluate IBD as a differential diagnosis or an emergent condition in patients with AN.

"If I could survive without eating, it would be a huge relief": Development and initial validation of the Fear of Food Questionnaire

BACKGROUND

Fear of food and behavioral avoidance of specific foods, food groups, and food related social situations can substantially reduce health related quality of life in individuals with a wide range of conditions that affect appetite, eating behavior, and digestion, including irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), vomit and choking phobias, and food allergies/sensitivities. When this avoidance leads to weight/nutritional and/or psychosocial impairment, the diagnostic criteria for Avoidant/restrictive food intake disorder (ARFID) are met. Fear of food is an important target for interventions designed to improve psychosocial functioning and quality of life in such individuals. The purpose of this research was to develop and validate a novel measure of fear of food.

METHODS

Participants (n = 1138) were recruited from ongoing clinical trials for both IBD and IBS, from Amazon's Mechanical Turk, from Reddit support forums for IBS, IBD, and vomit phobia, and from an undergraduate subject pool. Exploratory and confirmatory factor analysis, Pearson's correlations, one-way ANOVA, and intraclass correlation coefficients were used to assess the validity and reliability of the Fear of Food Questionnaire.

RESULTS

The final 18 item questionnaire showed excellent internal consistency, test-retest reliability, convergent validity, discriminative (known groups) validity, as well as good factor structure. Fear of food was highly correlated with visceral hypersensitivity, catastrophizing, GI symptom severity and health related quality of life, as well as with self-reported Fear-ARFID symptoms. Individuals meeting study criteria for Fear-ARFID reported the highest scores relative to control and other analogue clinical groups.

CONCLUSION

The Fear of Food Questionnaire appears to be reliable and valid across populations and may be a valuable tool in the assessment and treatment of Fear-ARFID.

Irritable Bowel Syndrome and Eating Disorders: A Burgeoning Concern in Gastrointestinal Clinics

Irritable bowel syndrome affects 10% to 15% of the population, and up to 90% of patients with irritable bowel syndrome exclude certain foods to improve their gastrointestinal symptoms. Although focused dietary restrictions are a normal, adaptive response, restrictions can spiral out of control and result in maladaptive restriction. Dietary therapies are rapidly becoming first-line treatment of irritable bowel syndrome, and gastroenterologists need to be aware of red flag symptoms of maladaptive eating patterns and the negative effects of prescribing restrictive diets. There is also growing awareness of the association between eating disorders and gastrointestinal symptoms, including irritable bowel syndrome symptoms.

Rationale and development of a manualised dietetic intervention for adults undergoing psychological treatment for an eating disorder

PURPOSE

Due to the current dearth of literature regarding dietetic treatment for patients with an eating disorder (ED), no manualised dietetic interventions exist to enable the testing of dietetic treatments in this population. This paper aims to: (1) describe the rationale and development of a manualised dietetic intervention for adults undergoing concurrent psychological treatment for an ED; and (2) provide an overview of the feasibility testing of this intervention.

METHODS

Current best evidence to date for dietetic treatment in EDs was utilised to develop a manualised dietetic intervention for feasibility testing alongside outpatient psychological 'treatment as usual'.

RESULTS

The developed intervention consists of five, dietitian-delivered outpatient sessions: (1) getting started; (2) mechanical eating and dietary rules; (3) estimating portion sizes and social eating; (4) maximising your meal plan and meal preparation; and (5) review and treatment planning as well as pre- and post-intervention assessments.

CONCLUSION

This paper is intended as a resource for clinicians and researchers in the conduct of future studies examining dietetic treatment for patients with an ED.

LEVEL OF EVIDENCE

Level V, description of a new manualised, reproducible dietetic intervention.

Evaluating disorders of gut-brain interaction in eating disorders

OBJECTIVE

Eating disorders commonly co-occur with gastrointestinal problems. This case-control study aimed to (a) document the prevalence of disorders of gut-brain interaction (DGBI) in eating disorders, (b) examine the specific impact of disordered eating behaviors on the risk of DGBI, and (c) explore the impact of current eating disorder psychopathology on DGBI.

METHOD

We included 765 cases with eating disorders and 1,240 controls. DGBI were assessed via the ROME III questionnaire. Prevalences of DGBI were calculated across eating disorder diagnoses (anorexia nervosa, bulimia nervosa, and multiple eating disorders) and in controls. The association between disordered eating behaviors and DGBI was examined using logistic regression models. Lastly, we compared the total number of DGBI in individuals with high versus low current eating disorder symptoms.

RESULTS

A large majority (88.2-95.5%) of individuals with eating disorders reported at least one DGBI and 34.8-48.7% reported three or more DGBI. Of the DGBI categories, functional bowel disorders were the most commonly endorsed category, and of the individual DGBI, irritable bowel syndrome was the most frequently reported (43.9-58.8%). All investigated disordered eating behaviors showed a positive association with most DGBI categories. Finally, individuals reporting high current eating disorder symptoms reported higher mean number of DGBI (3.03-3.34) than those with low current symptoms (1.60-1.84).

DISCUSSION

The directionality and mechanisms underlying the nature of the relationship between gastrointestinal and eating disorder symptoms is worthy of further study and clinicians should adopt an integrated approach by attending to both gastrointestinal and eating disorder symptoms in their patients.

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.

Gastrointestinal symptoms following treatment for anorexia nervosa: A systematic literature review

OBJECTIVE

Gastrointestinal (GI) disturbances are a frequent and burdensome experience for patients with anorexia nervosa (AN). How GI symptoms respond to current interventions is not well characterized, yet is critical to facilitate treatment success, and to inform the development of new treatments for AN. Therefore, the aim of this systematic review was to identify which treatments are effective in improving GI symptoms in patients with AN.

METHOD

A systematic search for studies of AN treatments measuring GI symptoms pre- and post-treatment was conducted in May 2020 (PROSPERO ID: CRD42020181328). After removal of duplicates, title and abstracts of 3,370 studies were screened. Methodological quality was assessed using National Institute of Health Quality Assessment Tool.

RESULTS

Following full-text screening, 13 studies (12 observational studies and 1 randomized double-blind placebo-controlled trial) with 401 participants met eligibility criteria and were included. All observational studies included a component of nutritional rehabilitation, with half (n = 6) involving concurrent psychological treatment. The randomized controlled trial reported a drug therapy. Eleven studies reported an improvement in all (n = 6) or at least one (n = 5) patient-reported GI symptom following treatment. Two studies reported no change. Methodological quality was fair or poor across all studies.

DISCUSSION

This is the first systematic review to synthesize available evidence on the trajectory of patient-reported GI symptoms from commencement to end of treatment for AN. The results suggest that most studies showed improvement in one or more GI symptom in response to current treatments. Future therapeutic approaches should consider GI symptoms within their design for optimal treatment adherence and outcomes.

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.

Role of microbiota-gut-brain axis dysfunctions induced by infections in the onset of anorexia nervosa

Anorexia nervosa (AN) is an eating disorder characterized by low food intake, severe body weight loss, intense fear of gaining weight, and dysmorphophobia. This chronic disease is associated with both psychiatric and somatic comorbidities. Over the years, clinical studies have accumulated evidence that viral or bacterial infections may promote the onset of eating disorders such as AN. This review aims to describe how infections and the subsequent immune responses affect food intake regulation in the short term and also how these processes may lead to long-term intestinal disorders, including gut barrier disruption and gut microbiota dysbiosis, even after the clearance of the pathogens. We discuss in particular how infection-mediated intestinal dysbiosis may promote the onset of several AN symptoms and comorbidities, including appetite dysregulation, functional gastrointestinal disorders, and mood disorders.

Gut microbiome dysbiosis in anorexia nervosa

Anorexia nervosa (AN) is described as an eating disorder, which is characterized by malnutrition, a fear of gaining body mass, and a disturbed self-body image. This disease is dependent on biological, psychological and socio-cultural factors. Among the various biological factors, the importance of intestinal microbiota has recently attracted much attention. Identification of the gut microbiota dysbiosis in patients with AN has opened new and promising research directions. Recent observations focus in particular on the association between intestinal microorganisms and the occurrence of functional gastrointestinal disorders associated with anorexia, anxiety and depression, as well as the regulation of eating habits. The composition of the gut microbiota differs between patients with AN and individuals with normal body mass. This is due to the incorrect diet of patients; on the other hand, there is growing interest in the role of intestinal microbiota in the pathogenesis of AN, its changes through re-nutrition practices, and in particular the modulation of intestinal microbiological composition by means of nutritional interventions or the use of preand probiotics as standard supplements therapy of eating disorders. There is a need for further research about the microbiome - intestine - brain axis. Furthermore, consequences of changes in dietary habits as part of AN treatment are also unknown. However, better knowledge about the relationship between the gut microbiome and the brain can help improve the treatment of this disorder. This review aims to present the current knowledge about the potential role of intestinal microbiota in the pathogenesis, course and treatment of AN.

The Role of the Gut Microbiome, Immunity, and Neuroinflammation in the Pathophysiology of Eating Disorders

There is a growing recognition that both the gut microbiome and the immune system are involved in a number of psychiatric illnesses, including eating disorders. This should come as no surprise, given the important roles of diet composition, eating patterns, and daily caloric intake in modulating both biological systems. Here, we review the evidence that alterations in the gut microbiome and immune system may serve not only to maintain and exacerbate dysregulated eating behavior, characterized by caloric restriction in anorexia nervosa and binge eating in bulimia nervosa and binge eating disorder, but may also serve as biomarkers of increased risk for developing an eating disorder. We focus on studies examining gut dysbiosis, peripheral inflammation, and neuroinflammation in each of these eating disorders, and explore the available data from preclinical rodent models of anorexia and binge-like eating that may be useful in providing a better understanding of the biological mechanisms underlying eating disorders. Such knowledge is critical to developing novel, highly effective treatments for these often intractable and unremitting eating disorders.

Biased Ghrelin Receptor Signaling and the Dopaminergic System as Potential Targets for Metabolic and Psychological Symptoms of Anorexia Nervosa

Anorexia Nervosa (AN) is a complex disease that impairs the metabolic, mental and physiological health of affected individuals in a severe and sometimes lethal way. Many of the common symptoms in AN patients, such as reduced food intake, anxiety, impaired gut motility or overexercising are connected to both the orexigenic gut hormone ghrelin and the dopaminergic system. Targeting the ghrelin receptor (GhrR) to treat AN seems a promising possibility in current research. However, GhrR signaling is highly complex. First, the GhrR can activate four known intracellular pathways Gαq, Gαi/o, Gα12/13 and the recruitment of β-arrestin. Biased signaling provides the possibility to activate or inhibit only one or a subset of the intracellular pathways of a pleiotropic receptor. This allows specific targeting of physiological functions without adverse effects. Currently little is known on how biased signaling could specifically modulate GhrR effects. Second, GhrR signaling has been shown to be interconnected with the dopaminergic system, particularly in the context of AN symptoms. This review highlights that a biased agonist for the GhrR may be a promising target for the treatment of AN, however extensive and systematic translational studies are still needed and the connection to the dopaminergic system has to be taken into account.

Medical Complications of Anorexia Nervosa

OBJECTIVE

The purpose of this study was to describe the medical complications of anorexia nervosa (AN) to enable a consult-liaison psychiatrist to be familiar with these complications when involved with the care of a hospitalized patient with AN.

METHODS

Comprehensive PubMed search of English language publications of adult patients with AN was carried out using keywords, phrases, and medical subject headings of anorexia nervosa-medical complications, cardiac, osteoporosis, gastrointestinal, hematological, and endocrine. The database search was restricted by time of publication of studies from 2005 to 2020.

RESULTS

Every organ system can be adversely affected by AN. Most are fully reversible with time and informed medical care. A multidisciplinary team is needed to optimally care for patients who are hospitalized as a result of the medical complications of their AN.

CONCLUSIONS

Consult-liaison psychiatrists are asked to help in the care of patients with AN who are admitted to a hospital because of a medical complication of their illness. Being familiar with these complications and their treatments will optimize their hospital stays and the care provided. In addition, involving other relevant ancillary services is an important care consideration.

Which Symptoms, Complaints and Complications of the Gastrointestinal Tract Occur in Patients With Eating Disorders? A Systematic Review and Quantitative Analysis

BACKGROUND

Eating disorders (ED) such as anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED) are often accompanied by a variety of psychological and physical comorbidities. Gastrointestinal (GI) symptoms are a classical feature in most patients with ED. The heterogeneity of studies on this topic is high, making it difficult to have a clear overview. The aim of this systematic review is therefore to provide an overview of subjectively and objectively measured differences and changes in the GI tract in patients with EDs, along with the occurrence of GI complications.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Google Scholar to find all relevant studies examining GI problems in AN, BN, and BED. Quantitative analyses were performed for objective GI physiology measures where applicable.

RESULTS

The review differentiated between ED types and also between studies that report GI outcomes of ED in (i) human studies with an ED diagnosis excluding case reports that provide an overview of GI problems in ED and (ii) case reports with an ED diagnosis describing rare GI complications in ED. GI symptoms and impaired gastric transit times were frequent features of EDs with specific differences found for the ED types. During the time course of treatment, GI symptoms changed and/or improved but not completely. GI complications extended the range of GI problems observed, including a variety of serious complications such as gastric dilatation.

CONCLUSIONS

Problems of the GI tract are frequent in patients with ED and it is likely that they complicate therapy, especially in patients with AN.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42019100585.

Eating Disorders and Gastrointestinal Diseases

Eating disorders (ED) are frequently associated with a wide range of psychiatric or somatic comorbidities. The most relevant ED are anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorders (BED). Patients with ED exhibit both upper and lower gastrointestinal (GI) symptoms. Evidence of alterations throughout the GI tract in ED will be analyzed given the role of the GI tract in food intake and its regulation. It remains a matter of debate whether GI disorders are inherent manifestations of ED or the results of malnutrition occurring from ED. Moreover, recent clinical studies have highlighted the growing role of intestinal microbiota in the pathogenesis of ED, making it possible to hypothesize a modulation of intestinal microbiota as a co-adjuvant to standard therapy. The aim of this review is to analyze the link between ED and GI diseases and to present, where known, the potential key factors underlying these conditions. Conclusions: The presence of GI disorders should be investigated in patients with ED. Screening for ED should also be encouraged in individuals seeking treatment for unexplained GI complaints to better address therapeutic issues that surround these difficult medical conditions.

Eating Disorders and Gastrointestinal Diseases

Eating disorders (ED) are frequently associated with a wide range of psychiatric or somatic comorbidities. The most relevant ED are anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorders (BED). Patients with ED exhibit both upper and lower gastrointestinal (GI) symptoms. Evidence of alterations throughout the GI tract in ED will be analyzed given the role of the GI tract in food intake and its regulation. It remains a matter of debate whether GI disorders are inherent manifestations of ED or the results of malnutrition occurring from ED. Moreover, recent clinical studies have highlighted the growing role of intestinal microbiota in the pathogenesis of ED, making it possible to hypothesize a modulation of intestinal microbiota as a co-adjuvant to standard therapy. The aim of this review is to analyze the link between ED and GI diseases and to present, where known, the potential key factors underlying these conditions. Conclusions: The presence of GI disorders should be investigated in patients with ED. Screening for ED should also be encouraged in individuals seeking treatment for unexplained GI complaints to better address therapeutic issues that surround these difficult medical conditions.

Gastrointestinal Sensing of Meal-Related Signals in Humans, and Dysregulations in Eating-Related Disorders

The upper gastrointestinal (GI) tract plays a critical role in sensing the arrival of a meal, including its volume as well as nutrient and non-nutrient contents. The presence of the meal in the stomach generates a mechanical distension signal, and, as gastric emptying progresses, nutrients increasingly interact with receptors on enteroendocrine cells, triggering the release of gut hormones, with lipid and protein being particularly potent. Collectively, these signals are transmitted to the brain to regulate appetite and energy intake, or in a feedback loop relayed back to the upper GI tract to further adjust GI functions, including gastric emptying. The research in this area to date has provided important insights into how sensing of intraluminal meal-related stimuli acutely regulates appetite and energy intake in humans. However, disturbances in the detection of these stimuli have been described in a number of eating-related disorders. This paper will review the GI sensing of meal-related stimuli and the relationship with appetite and energy intake, and examine changes in GI responses to luminal stimuli in obesity, functional dyspepsia and anorexia of ageing, as examples of eating-related disorders. A much better understanding of the mechanisms underlying these dysregulations is still required to assist in the development of effective management and treatment strategies in the future.

Activity Based Anorexia as an Animal Model for Anorexia Nervosa-A Systematic Review

Anorexia nervosa (AN) is a severe eating disorder affecting around 1 per 100 persons. However, the knowledge about its underlying pathophysiology is limited. To address the need for a better understanding of AN, an animal model was established early on in the late 1960's: the activity-based anorexia (ABA) model in which rats have access to a running wheel combined with restricted food access leading to self-starving/body weight loss and hyperactivity. Both symptoms, separately or combined, can also be found in patients with AN. The aim of this systematic review was to compile the current knowledge about this animal model as well as to address gaps in knowledge. Using the data bases of PubMed, Embase and Web of science 102 publications were identified meeting the search criteria. Here, we show that the ABA model mimics core features of human AN and has been characterized with regards to brain alterations, hormonal changes as well as adaptations of the immune system. Moreover, pharmacological interventions in ABA animals and new developments, such as a chronic adaptation of the ABA model, will be highlighted. The chronic model might be well suited to display AN characteristics but should be further characterized. Lastly, limitations of the model will be discussed.

Medication in AN: A Multidisciplinary Overview of Meta-Analyses and Systematic Reviews

Drugs are widely prescribed for anorexia nervosa in the nutritional, somatic, and psychiatric fields. There is no systematic overview in the literature, which simultaneously covers all these types of medication. The main aims of this paper are (1) to offer clinicians an overview of the evidence-based data in the literature concerning the medication (psychotropic drugs and medication for somatic and nutritional complications) in the field of anorexia nervosa since the 1960s, (2) to draw practical conclusions for everyday practise and future research. Searches were performed on three online databases, namely MEDLINE, Epistemonikos and Web of Science. Papers published between September 2011 and January 2019 were considered. Evidence-based data were identified from meta-analyses, if there were none, from systematic reviews, and otherwise from trials (randomized or if not open-label studies). Evidence-based results are scarce. No psychotropic medication has proved efficacious in terms of weight gain, and there is only weak data suggesting it can alleviate certain psychiatric symptoms. Concerning nutritional and somatic conditions, while there is no specific, approved medication, it seems essential not to neglect the interest of innovative therapeutic strategies to treat multi-organic comorbidities. In the final section we discuss how to use these medications in the overall approach to the treatment of anorexia nervosa.