Course of avoidant/restrictive food intake disorder: Emergence of overvaluation of shape/weight

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) is a feeding/eating disorder characterized by avoidance/restriction of food intake by volume and/or variety. The emergence of shape/weight-related eating disorder symptoms in the longitudinal course of ARFID is an important clinical phenomenon that is neither robustly documented nor well understood. We aimed to characterize the emergence of eating disorder symptoms among adults with an initial diagnosis of ARFID who ultimately developed other eating disorders.

METHOD

Thirty-five participants (94% female; Mage = 23.17 ± 5.84 years) with a history of ARFID and a later, separate eating disorder completed clinical interviews (i.e., Structured Clinical Interview for DSM-5 - Research Version and Longitudinal Interval Follow-Up Evaluation) assessing the period between ARFID and the later eating disorder. Participants used calendars to aid in recall of symptoms over time. Descriptive statistics characterized the presence, order of, and time to each symptom. Paired samples t-tests compared weeks to emergence between symptoms.

RESULTS

Most participants (71%) developed restricting eating disorders; the remainder (29%) developed binge-spectrum eating disorders. Cognitive symptoms (e.g., shape/weight concerns) tended to onset initially and were followed by behavioral symptoms. Shape/weight-related food avoidance presented first, objective binge eating, fasting, and excessive exercise occurred next, followed by subjective binge eating and purging.

CONCLUSIONS

Diagnostic crossover from ARFID to another (typically restricting) eating disorder following the development of shape/weight concerns may represent the natural progression of a singular clinical phenomenon. Findings identify potential pathways from ARFID to the development of another eating disorder, highlighting possible clinical targets for preventing this outcome.

Avoidant/restrictive food intake disorder symptoms are not as frequent as other eating disorder symptoms when ulcerative colitis is in remission

BACKGROUND AND AIM

Recent studies have shown that up to 53% of patients with inflammatory bowel disease (IBD) screen positive for avoidant/restrictive food intake disorder (ARFID). There is however concern that ARFID screening rates are over-inflated in patients with active disease. We aimed to evaluate the frequency and characteristics of ARFID symptoms using the Nine Item ARFID Screen (NIAS), and to use another eating disorder measure, the Eating Disorder Examination-Questionnaire 8 (EDE-Q8), to rule-out/characterize other eating disorder cognitive and behavioral symptoms.

METHODS

Participants included adults with UC who are enrolled in an in an ongoing cohort study with quiescent UC (SCCAI ≤2 or fecal calprotectin <150 µg/g with corticosteroid-free clinical remission for ≥ 3 months) at baseline. We used self-reported data on demographics, gastrointestinal medications, medical comorbidities, NIAS scores, and other eating disorder symptom scores (8-item Eating Disorder Examination-Questionnaire; EDE-Q-8).

RESULTS

We included 101 participants who completed the NIAS at their baseline cohort assessment (age 49.9±16.5 years; 55% female). Eleven participants (11%) screened positively for ARFID on at least one NIAS subscale (n=8 male). Up to thirty participants (30%) screened positive for other eating disorder symptoms (EDE-Q-8 Global ≥2.3). Overall score distributions on the EDE-Q-8 showed that participants scored highest on the Weight Concern and Shape Concern subscales.

CONCLUSIONS

Among adults with UC in remission, we found a low rate of ARFID symptoms by the NIAS but a high rate of positive screens for other eating disorder symptoms.

Lower region-specific gray matter volume in females with atypical anorexia nervosa and anorexia nervosa

OBJECTIVE

Few studies have focused on brain structure in atypical anorexia nervosa (atypical AN). This study investigates differences in gray matter volume (GMV) between females with anorexia nervosa (AN) and atypical AN, and healthy controls (HC).

METHOD

Structural magnetic resonance imaging data were acquired for 37 AN, 23 atypical AN, and 41 HC female participants. Freesurfer was used to extract GMV, cortical thickness, and surface area for six brain lobes and associated cortical regions of interest (ROI). Primary analyses employed linear mixed-effects models to compare group differences in lobar GMV, followed by secondary analyses on ROIs within significant lobes. We also explored relationships between cortical gray matter and both body mass index (BMI) and symptom severity.

RESULTS

Our primary analyses revealed significant lower GMV in frontal, temporal and parietal areas (FDR < .05) in AN and atypical AN when compared to HC. Lobar GMV comparisons were non-significant between atypical AN and AN. The parietal lobe exhibited the greatest proportion of affected cortical ROIs in both AN versus HC and atypical AN versus HC. BMI, but not symptom severity, was found to be associated with cortical GMV in the parietal, frontal, temporal, and cingulate lobes. No significant differences were observed in cortical thickness or surface area.

DISCUSSION

We observed lower GMV in frontal, temporal, and parietal areas, when compared to HC, but no differences between AN and atypical AN. This indicates potentially overlapping structural phenotypes between these disorders and evidence of brain changes among those who are not below the clinical underweight threshold.

PUBLIC SIGNIFICANCE

Despite individuals with atypical anorexia nervosa presenting above the clinical weight threshold, lower cortical gray matter volume was observed in partial, temporal, and frontal cortices, compared to healthy individuals. No significant differences were found in cortical gray matter volume between anorexia nervosa and atypical anorexia nervosa. This underscores the importance of continuing to assess and target weight gain in clinical care, even for those who are presenting above the low-weight clinical criteria.

Avoidant/restrictive food intake disorder differs from anorexia nervosa in delay discounting

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) and anorexia nervosa (AN) are the two primary restrictive eating disorders; however, they are driven by differing motives for inadequate dietary intake. Despite overlap in restrictive eating behaviors and subsequent malnutrition, it remains unknown if ARFID and AN also share commonalities in their cognitive profiles, with cognitive alterations being a key identifier of AN. Discounting the present value of future outcomes with increasing delay to their expected receipt represents a core cognitive process guiding human decision-making. A hallmark cognitive characteristic of individuals with AN (vs. healthy controls [HC]) is reduced discounting of future outcomes, resulting in reduced impulsivity and higher likelihood of favoring delayed gratification. Whether individuals with ARFID display a similar reduction in delay discounting as those with AN (vs. an opposing bias towards increased delay discounting or no bias) is important in informing transdiagnostic versus disorder-specific cognitive characteristics and optimizing future intervention strategies.

METHOD

To address this research question, 104 participants (ARFID: n = 57, AN: n = 28, HC: n = 19) completed a computerized Delay Discounting Task. Groups were compared by their delay discounting parameter (ln)k.

RESULTS

Individuals with ARFID displayed a larger delay discounting parameter than those with AN, indicating steeper delay discounting (M ± SD = -6.10 ± 2.00 vs. -7.26 ± 1.73, p = 0.026 [age-adjusted], Hedges' g = 0.59), with no difference from HC (p = 0.514, Hedges' g = -0.35).

CONCLUSION

Our findings provide a first indication of distinct cognitive profiles among the two primary restrictive eating disorders. The present results, together with future research spanning additional cognitive domains and including larger and more diverse samples of individuals with ARFID (vs. AN), will contribute to identifying maintenance mechanisms that are unique to each disorder as well as contribute to the optimization and tailoring of treatment strategies across the spectrum of restrictive eating disorders.

Cognitive-behavioral therapy for avoidant/restrictive food intake disorder: A proof-of-concept for mechanisms of change and target engagement

BACKGROUND

Cognitive-behavioral therapy for avoidant/restrictive food intake disorder (ARFID; CBT-AR) theoretically targets three prototypic motivations (sensory sensitivity, lack of interest/low appetite, fear of aversive consequences), aligned with three modularized interventions. As an exploratory investigation, we: (1) evaluated change in candidate mechanisms in relationship to change in ARFID severity, and (2) tested if assignment (vs. not) to a module resulted in larger improvements in the corresponding mechanism.

METHOD

Males and females (N = 42; 10-55 years) participated in an open trial of CBT-AR.

RESULTS

Decreases in scaled scores for each candidate mechanism had medium to large correlations with decreases in ARFID severity-sensory sensitivity: -0.7 decrease (r = .42, p = .01); lack of interest/low appetite: -0.3 decrease (r = .60, p < .0001); and fear of aversive consequences: -1.1 decrease (r = .33, p = .05). Linear mixed models revealed significant weekly improvements for each candidate mechanism across the full sample (ps < .0001). There were significant interactions for the sensory and fear of aversive consequences modules-for each, participants who received the corresponding module had significantly larger decreases in the candidate mechanism than those who did not receive the module.

DISCUSSION

Sensory sensitivity and fear of aversive consequences improved more if the CBT-AR module was received, but lack of interest/low appetite may improve regardless of receipt of the corresponding module. Future research is needed to test target engagement in CBT-AR with adaptive treatment designs, and to identify valid and sensitive measures of candidate mechanisms.

PUBLIC SIGNIFICANCE

The mechanisms through which components of CBT-AR work have yet to be elucidated. We conducted an exploratory investigation to test if assignment (vs. not) to a CBT-AR module resulted in larger improvements in the corresponding prototypic ARFID motivation that the module intended to target. Measures of the sensory sensitivity and the fear of aversive consequences motivations improved more in those who received the corresponding treatment module, whereas the lack of interest/low appetite measure improved regardless of if the corresponding module was received.

Assessing clinician competence in the delivery of cognitive-behavioural therapy for eating disorders: development of the Cognitive-Behavioural Therapy Scale for Eating Disorders (CBTS-ED)

Evidence-based cognitive-behaviour therapy for eating disorders (CBT-ED) differs from other forms of CBT for psychological disorders, making existing generic CBT measures of therapist competence inadequate for evaluating CBT-ED. This study developed and piloted the reliability of a novel measure of therapist competence in this domain-the Cognitive Behaviour Therapy Scale for Eating Disorders (CBTS-ED). Initially, a team of CBT-ED experts developed a 26-item measure, with general (i.e. present in every session) and specific (context- or case-dependent) items. To determine statistical properties of the measure, nine CBT-ED experts and eight non-experts independently observed six role-played mock CBT-ED therapy sessions, rating the therapists' performance using the CBTS-ED. The inter-item consistency (Cronbach's alpha and McDonald's omega) and inter-rater reliability (ICC) were assessed, as appropriate to the clustering of the items. The CBTS-ED demonstrated good internal consistency and moderate/good inter-rater reliability for the general items, at least comparable to existing generic CBT scales in other domains. An updated version is proposed, where five of the 16 "specific" items are reallocated to the general group. These preliminary results suggest that the CBTS-ED can be used effectively across both expert and non-expert raters, though less experienced raters might benefit from additional training in its use.

Drug discovery for heart failure targeting myosin-binding protein C

Cardiac MyBP-C (cMyBP-C) interacts with actin and myosin to fine-tune cardiac muscle contractility. Phosphorylation of cMyBP-C, which reduces the binding of cMyBP-C to actin and myosin, is often decreased in patients with heart failure (HF) and is cardioprotective in model systems of HF. Therefore, cMyBP-C is a potential target for HF drugs that mimic its phosphorylation and/or perturb its interactions with actin or myosin. We labeled actin with fluorescein-5-maleimide (FMAL) and the C0-C2 fragment of cMyBP-C (cC0-C2) with tetramethylrhodamine (TMR). We performed two complementary high-throughput screens (HTS) on an FDA-approved drug library, to discover small molecules that specifically bind to cMyBP-C and affect its interactions with actin or myosin, using fluorescence lifetime (FLT) detection. We first excited FMAL and detected its FLT, to measure changes in fluorescence resonance energy transfer (FRET) from FMAL (donor) to TMR (acceptor), indicating binding. Using the same samples, we then excited TMR directly, using a longer wavelength laser, to detect the effects of compounds on the environmentally sensitive FLT of TMR, to identify compounds that bind directly to cC0-C2. Secondary assays, performed on selected modulators with the most promising effects in the primary HTS assays, characterized the specificity of these compounds for phosphorylated versus unphosphorylated cC0-C2 and for cC0-C2 versus C1-C2 of fast skeletal muscle (fC1-C2). A subset of identified compounds modulated ATPase activity in cardiac and/or skeletal myofibrils. These assays establish the feasibility of the discovery of small-molecule modulators of the cMyBP-C-actin/myosin interaction, with the ultimate goal of developing therapies for HF.

Anticipatory and consummatory pleasure in avoidant/restrictive food intake disorder

BACKGROUND

Recent research suggests that individuals with eating disorders (EDs) report elevated anhedonia, or loss of pleasure. Although individuals with avoidant/restrictive food intake disorder (ARFID) often express that they do not look forward to eating, it is unclear whether they experience lower pleasure than those without EDs. Thus, identifying whether individuals with ARFID experience anhedonia may yield important insights that inform clinical conceptualization and treatment.

METHODS

A sample of 71 participants ages 10-23 with full and subthreshold ARFID and 33 healthy controls (HCs) completed the Pica, ARFID, and Rumination Disorder Interview, a diagnostic interview to assess ARFID profile severity (lack of interest in food, sensory sensitivity, fear of aversive consequences) and the Temporal Experience of Pleasure Scale (TEPS), a self-report measure of consummatory and anticipatory pleasure. Statistical analyses were performed using the full TEPS and also the TEPS with food-related items removed.

RESULTS

The ARFID group reported significantly lower anticipatory and consummatory pleasure compared to HCs, but these differences were no longer significant after controlling for depression, nor after removing food items from the TEPS. Within the ARFID sample, greater ARFID severity was associated with lower anticipatory pleasure across analyses, and greater endorsement of the lack of interest in food profile was related to lower anticipatory pleasure. ARFID severity was also associated with lower consummatory pleasure using the full TEPS, but this relationship was no longer significant with food items removed.

CONCLUSIONS

These results provide initial evidence for lower pleasure before potentially pleasurable events in individuals with more severe ARFID, particularly those with the lack of interest phenotype. Our findings also suggest that depression is likely to contribute low pleasure in this population. Future research should seek to further characterize how dimensions of pleasure relate to the maintenance and treatment of ARFID symptoms.

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.

Defining the Oligometastatic State and Predicting Overall Survival in Uterine Cancers using a Recursive Partitioning Analysis: A National Cancer Database Analysis

PURPOSE/OBJECTIVE(S)

Oligometastatic disease is an intermediate state between locoregional disease and widely metastatic disease. Studies have shown an overall survival advantage in oligometastatic patients treated aggressively in multiple cancers. However, few studies have explored this relationship in oligometastatic gynecological cancers. In this study, we sought to identify if an oligometastatic state with improved overall survival exists in uterine cancer and whether treatment patterns, or patient factors play a role in survival.

MATERIALS/METHODS

The National Cancer Database was retrospectively analyzed in patients diagnosed with uterine cancer between 2004-2019. We excluded patients with non-metastatic disease at diagnosis, lack of metastatic sites listed, multiple primaries and missing survival data. Survival analyses were performed using Cox proportional hazards analyses and the Kaplan-Meier method and differences between groups were evaluated with log-rank tests. Recursive partitioning analysis (RPA) was performed using the rpart package in R.

RESULTS

Amongst 641,276 women with uterine cancer, 17,343 were ultimately in our study population after exclusion who had a median age of 64 (range 18-90), median overall survival of 11.1 months, and a total of 24,337 metastases that represented the following metastatic sites: lung (35%), other (24%) (sites "other" than bone, brain liver or lung), liver (15%), bone (12%), distant lymph nodes (10%), brain (3%) and carcinomatosis (1%). Multivariate cox proportional hazards analysis identified the following variables as significantly associated with survival, which were then used for RPA: one metastatic site, treatment, grade, age, race, Charlson-Deyo score. The data was split 70/30% for training and validation, respectively. A survival model was built using RPA on the training data with 10-fold cross-validation and had accuracy of 76.25% (p = 3.393e-0.5). Survival prediction was performed on the internal validation data set with 76.69% accuracy (p = 0.004). RPA stratified 4 groups with the following median survivals: 5.9, 8.6, 29.5, and 43.8 months (log-rank test p<0.0001). The group with the best overall survival was defined by 1 metastatic site (carcinomatosis, distant lymph nodes and "other"), combination treatment with systemic therapy and radiation or surgery and low-grade histology.

CONCLUSION

An oligometastatic state with involvement of one metastatic site does exist with improved survival in uterine cancer. The RPA defined groups may aid in identifying patients that are best suited for aggressive definitive combination therapy versus those that would be better suited for comfort care. Analysis is ongoing and will further delineate the relationship between specific treatment modalities and overall survival in patients with one metastatic site. This study may set the foundation for a prospective clinical trial.

Oxytocin response to food intake in avoidant/restrictive food intake disorder

OBJECTIVE

To investigate the response of anorexigenic oxytocin to food intake among adolescents and young adults with avoidant/restrictive food intake disorder (ARFID), a restrictive eating disorder characterized by lack of interest in food or eating, sensory sensitivity to food, and/or fear of aversive consequences of eating, compared with healthy controls (HC).

DESIGN

Cross-sectional.

METHODS

A total of 109 participants (54 with ARFID spectrum and 55 HC) were instructed to eat a ∼400-kcal standardized mixed meal. We sampled serum oxytocin at fasting and at 30-, 60-, and 120-min postmeal. We tested the hypothesis that ARFID would show higher mean oxytocin levels across time points compared with HC using a mixed model ANOVA. We then used multivariate regression analysis to identify the impact of clinical characteristics (sex, age, and body mass index [BMI] percentile) on oxytocin levels in individuals with ARFID.

RESULTS

Participants with ARFID exhibited greater mean oxytocin levels at all time points compared with HC, and these differences remained significant even after controlling for sex and BMI percentile (P = .004). Clinical variables (sex, age, and BMI percentile) did not show any impact on fasting and postprandial oxytocin levels among individuals with ARFID.

CONCLUSIONS

Consistently high oxytocin levels might be involved in low appetite and sensory aversions to food, contributing to food avoidance in individuals with ARFID.

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.

Low bone mineral density is found in low weight female youth with avoidant/restrictive food intake disorder and associated with higher PYY levels

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) is a restrictive eating disorder commonly associated with medical complications of undernutrition and low weight. In adolescence, a critical time for bone accrual, the impact of ARFID on bone health is uncertain. We aimed to study bone health in low-weight females with ARFID, as well as the association between peptide YY (PYY), an anorexigenic hormone with a role in regulation of bone metabolism, and bone mineral density (BMD) in these individuals. We hypothesized that BMD would be lower in low-weight females with ARFID than healthy controls (HC), and that PYY levels would be negatively associated with BMD.

METHODS

We performed a cross-sectional study in 14 adolescent low-weight females with ARFID and 20 HC 10-23 years old. We assessed BMD (total body, total body less head and lumbar spine) using dual x-ray absorptiometry (DXA) and assessed fasting total PYY concentration in blood.

RESULTS

Total body BMD Z-scores were significantly lower in ARFID than in HC (- 1.41 ± 0.28 vs. - 0.50 ± 0.25, p = 0.021). Mean PYY levels trended higher in ARFID vs. HC (98.18 ± 13.55 pg/ml vs. 71.40 ± 5.61 pg/ml, p = 0.055). In multivariate analysis within the ARFID group, PYY was negatively associated with lumbar BMD adjusted for age (β = -0.481, p = 0.032).

CONCLUSION

Our findings suggest that female adolescents with low-weight ARFID may have lower BMD than healthy controls and that higher PYY levels may be associated with lower BMD at some, but not all, sites in ARFID. Further research with larger samples will be important to investigate whether high PYY drives bone loss in ARFID.

Neural activation of regions involved in food reward and cognitive control in young females with anorexia nervosa and atypical anorexia nervosa versus healthy controls

Anorexia nervosa (AN) and atypical AN (AtypAN) are complex neurobiological illnesses that typically onset in adolescence with an often treatment-refractory and chronic illness trajectory. Aberrant eating behaviors in this population have been linked to abnormalities in food reward and cognitive control, but prior studies have not examined respective contributions of clinical characteristics and metabolic state. Research is needed to identify specific disruptions and inform novel intervention targets to improve outcomes. Fifty-nine females with AN (n = 34) or AtypAN (n = 25), ages 10-22 years, all ≤90% expected body weight, and 34 age-matched healthy controls (HC) completed a well-established neuroimaging food cue paradigm fasting and after a standardized meal, and we used ANCOVA models to investigate main and interaction effects of Group and Appetitive State on blood oxygenation level-dependent (BOLD) activation for the contrast of exposure to high-calorie food images minus objects. We found main effects of Group with greater BOLD activation in the dorsal anterior cingulate cortex (dACC), dorsolateral prefrontal cortex (DLPFC), hippocampus, caudate, and putamen for AN/AtypAN versus HC groups, and in the three-group model including AN, AtypAN, and HC (sub-)groups, where differences were primarily driven by greater activation in the AtypAN subgroup versus HC group. We found a main effect of Appetitive State with increased premeal BOLD activation in the hypothalamus, amygdala, nucleus accumbens, and caudate for models that included AN/AtypAN and HC groups, and in BOLD activation in the nucleus accumbens for the model that included AN, AtypAN, and HC (sub-)groups. There were no interaction effects of Group with Appetitive State for any of the models. Our findings demonstrate robust feeding-state independent group effects reflecting greater neural activation of specific regions typically associated with reward and cognitive control processing across AN and AtypAN relative to healthy individuals in this food cue paradigm. Differential activation of specific brain regions in response to the passive viewing of high-calorie food images may underlie restrictive eating behavior in this clinical population.

Lower Ghrelin Levels Are Associated With Higher Anxiety Symptoms in Adolescents and Young Adults With Avoidant/Restrictive Food Intake Disorder

Objective: Avoidant/restrictive food intake disorder (ARFID) is associated with increased risk for anxiety, which may adversely affect prognosis. The appetite-stimulating hormone, ghrelin, increases in response to stress, and exogenous ghrelin decreases anxiety-like behaviors in animal models. The aim of this study was to evaluate the relationship between ghrelin levels and measures of anxiety in youth with ARFID. We hypothesized that lower ghrelin levels would be associated with increased anxiety symptoms.

Methods: We studied a cross-sectional sample of 80 subjects with full and subthreshold ARFID diagnosed by DSM-5 criteria, aged 10-23 years (female, n = 39; male, n = 41). Subjects were enrolled in a study of the neurobiology of avoidant/restrictive eating conducted from August 2016 to January 2021. We assessed fasting ghrelin levels and anxiety symptoms (State-Trait Anxiety Inventory [STAI] and STAI for Children [STAI-C] measuring general trait anxiety; Beck Anxiety Inventory [BAI] and BAI for youth [BAI-Y] assessing cognitive, emotional, and somatic symptoms of anxiety; and Liebowitz Social Anxiety Scale [LSAS] assessing symptoms of social anxiety).

Results: Consistent with our hypothesis, ghrelin levels were inversely associated with anxiety symptoms as assessed by STAI/STAI-C T scores (r = -0.28, P = .012), BAI/BAI-Y T scores (r = -0.28, P = .010), and LSAS scores (r = -0.3, P = .027), all with medium effect sizes. Findings held in the full threshold ARFID group when adjusting for body mass index z scores (STAI/STAI-C T scores, β = -0.27, P = .024; BAI/BAI-Y T scores, β = -0.26, P = .034; LSAS, β = -0.34, P = .024).

Conclusions: These findings demonstrate that lower levels of ghrelin are associated with more severe anxiety symptoms in youth with ARFID and raise the question of whether ghrelin pathways could be targeted in the treatment of ARFID.

Drug discovery for heart failure targeting myosin-binding protein C

Cardiac MyBP-C (cMyBP-C) interacts with actin-myosin to fine-tune cardiac muscle contractility. Phosphorylation of cMyBP-C, which reduces binding of cMyBP-C to actin or myosin, is often decreased in heart failure (HF) patients, and is cardioprotective in model systems for HF. Therefore, cMyBP-C is a potential target for HF drugs that mimic phosphorylation and/or perturb its interactions with actin or myosin. We labeled actin with fluorescein-5-maleimide (FMAL), and the C0-C2 fragment of cMyBP-C (cC0-C2) with tetramethyl rhodamine (TMR). We performed two complementary high-throughput screens (HTS) on an FDA-approved drug library, to discover small molecules that specifically bind to cMyBP-C and affect its interactions with actin or myosin, using fluorescence lifetime (FLT) detection. We first excited FMAL and detected its FLT, to measure changes in fluorescence resonance energy transfer (FRET) from FMAL (donor) to TMR (acceptor), indicating binding and/or structural changes in the protein complex. Using the same samples, we then excited TMR directly, using a longer wavelength laser, to detect the effects of compounds on the environmentally sensitive FLT of TMR, to identify compounds that bind directly to cC0-C2. Secondary assays, performed on selected modulators with the most promising effects in the primary HTS assays, characterized specificity of these compounds for phosphorylated versus unphosphorylated cC0-C2 and for cC0-C2 versus C1-C2 of fast skeletal muscle (fskC1-C2). A subset of identified compounds modulated ATPase activity in cardiac and/or skeletal myofibrils. These assays establish feasibility for discovery of small-molecule modulators of the cMyBP-C-actin/myosin interaction, with the ultimate goal of developing therapies for HF.

Association Between Ghrelin and Body Weight Trajectory in Individuals With Anorexia Nervosa

Importance

Individuals with anorexia nervosa maintain extremely low body weights despite elevations in the circulating orexigenic hormone ghrelin. Whether circulating levels of endogenous ghrelin are associated with weight gain in anorexia nervosa is unknown.

Objective

To examine the association between baseline ghrelin and future weight change in individuals with anorexia nervosa.

Design, Setting, and Participants

This prospective cohort study was conducted between April 1, 2014, and March 31, 2020, in the US. Girls and women aged 10 to 22 years were recruited from the greater Boston area from community and area treatment centers, enrolled, and followed up for 18 months. Statistical analyses were performed between January and August 2022.

Exposures

Presence or absence of anorexia nervosa and elevations in endogenous ghrelin.

Main Outcomes and Measures

Changes in age- and sex-standardized body mass index percentiles from baseline to 9- and 18-month follow-up were the main outcomes of interest.

Results

A total of 68 girls and young women (11 [16%] Asian, 4 [6%] Hispanic or Latina, 51 [75%] White [non-Hispanic or Latina], and 2 [3%] other race or ethnicity), including 35 with anorexia nervosa and 33 healthy controls of similar Tanner stage, were included in this study. Anorexia nervosa and healthy control groups were not statistically different by race and ethnicity, Tanner stage, number completing follow-up visits, and the duration between baseline and follow-up visits. At baseline, individuals with anorexia nervosa were slightly older (median [IQR], 20.1 [18.5-21.0] vs 18.7 [14.7-19.4] years; P = .005), had lower body mass index percentiles (median [IQR], 2.4 [0.3-4.7] vs 52.9 [40.4-68.3]; P < .001), and had elevated circulating ghrelin area under the curve composite index (median [IQR], 1389.4 [1082.5-1646.4] vs 958.5 [743.0-1234.5] pg/mL; P = .003) compared with healthy individuals. In linear mixed-effects regression analyses, baseline ghrelin was associated with prospective weight gain after adjusting for diagnosis, age, race, and duration of follow-up (odds ratio, 2.35; 95% CI, 1.43-3.73; P = .004).

Conclusions and Relevance

In this cohort study, endogenous ghrelin was associated with longitudinal weight gain in individuals with anorexia nervosa. Further studies are warranted to confirm this result and examine its potential clinical utility in treatment development.

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.

A proposed trumping scheme for other specified feeding or eating disorder: Comment on Walsh et al., 2023

The recent systematic review by Walsh, Hagan, & Lockwood (Int J Eat Disord, in press) highlights the importance of further distinguishing atypical anorexia nervosa (atypical AN) from other feeding and eating disorders. The lack of a trumping scheme within other specified feeding or eating disorder (OSFED) hinders intervention selection in the clinical context and reduces reliability of diagnostic classification in research samples. Thus, we propose a trumping scheme within OSFED that mirrors the existing diagnostic algorithm in the main DSM-5-TR feeding and eating disorders section. According to this scheme, a diagnosis of atypical AN would override all other OSFED subcategories. Subthreshold bulimia nervosa (BN) would trump subthreshold binge-eating disorder (BED) and purging disorder; purging disorder would trump subthreshold BED and night eating syndrome; night eating syndrome would trump subthreshold BED; and subthreshold BED would trump subthreshold avoidant/restrictive food intake disorder (ARFID)-a novel presentation that we propose adding under the OSFED umbrella to parallel the existing subthreshold classifications for the main feeding and eating disorders. We hope this proposed OSFED trumping scheme will improve intervention selection and diagnostic reliability in clinical and research contexts, and serve as a catalyst for future research on these newly recognized-but common and impairing-feeding and eating disorder presentations.

Assessment and Treatment of Avoidant/Restrictive Food Intake Disorder

PURPOSE OF REVIEW

To review the literature pertaining to the assessment and treatment of avoidant/restrictive food intake disorder (ARFID) ten years following its introduction to DSM-5.

RECENT FINDINGS

Several structured clinical interviews for assessing ARFID have been developed, each with its own strengths and limitations. There is no clear leading self-report measure for tracking treatment progress and outcome in ARFID. Medical assessment is comprised of examining anthropometrics, vitamin deficiencies, and other comorbidities. To date, several studies have reported on cognitive behavioral therapy, family-based treatment, and other approaches to the treatment of ARFID. These treatments appear promising; however, they rely on data from clinical case series and very small randomized controlled trials. Several promising assessments and treatments for ARFID are in the early stages of research. Yet, controversies remain. These include (a) overlap with criteria for pediatric feeding disorder; (b) the optimal method for assessing nutrient deficiencies; (c) disciplines involved in treatment. Future research innovation is necessary to improve the psychometric properties of ARFID assessments and evaluate treatment efficacy with larger samples and randomized designs.

What Motivates Action for Gender Equality among Emerging Adult Women? The Importance of Critical Reflection, Efficacy, and Feminist Identity

The present study investigated whether critical consciousness (CC) and feminist identity help explain emerging adult women's participation in actions to reduce gender inequality. CC is an applied tool marginalized and oppressed youth can use to combat inequality. It is conceptualized as three components: Critical reflection, critical efficacy, and critical action. Youth who have reflected on inequality are theorized to act against injustice if they have critical efficacy. However, empirical support for connections among components is mixed and questions remain concerning the contexts in which and people for whom CC serves as a resource. For instance, CC has rarely been examined as a tool to reduce sexism. Furthermore, researchers theorize that social identity is related to CC, yet little empirical evidence exists testing these associations. Finally, CC is typically examined within samples of children and adolescents, although advances in cognitive development and identity suggest emerging adulthood is an ideal time to use CC. To begin to fill these gaps, we investigated whether the components of CC in association with feminist identity could predict when emerging adult women act against sexism. A serial mediation model revealed reflection may lead to action for women who identify as feminist and who report greater internal efficacy. The pathway through external efficacy was not significant. Findings suggest CC together with feminist identity may be tools women can employ to transform unjust social conditions and improve their lives. Applied applications of findings are considered.

Preliminary validation of the pica, ARFID and rumination disorder interview ARFID questionnaire (PARDI-AR-Q)

BACKGROUND

The Pica, ARFID, and Rumination Disorder Interview (PARDI) is a structured interview that can be used to determine diagnosis, presenting characteristics, and severity across three disorders, including avoidant/restrictive food intake disorder (ARFID). The purpose of this study was to evaluate the psychometric properties of a questionnaire focused specifically on ARFID (PARDI-AR-Q), which has the potential to provide related information with less participant burden.

METHODS

Adolescents and adults (n = 71, ages 14-40 years) with ARFID (n = 42) and healthy control participants (HC, n = 29) completed the PARDI-AR-Q and other measures. A subset of the ARFID group (n = 27) also completed the PARDI interview.

RESULTS

An exploratory factor analysis of proposed subscale items identified three factors corresponding to the ARFID phenotypes of avoidance based on the sensory characteristics of food, lack of interest in eating or food, and concern about aversive consequences of eating. Further analyses supported the internal consistency and convergent validity of the PARDI-AR-Q subscales, and subscale ratings on the questionnaire showed large and significant correlations (all p-values < 0.001; r's ranging from 0.48 to 0.77) with the corresponding subscales on the interview. The ARFID group scored significantly higher than HC on all subscales. Furthermore, 90% of the ARFID group scored positive on the PARDI-AR-Q diagnostic algorithm while 93% of the HC scored negative.

CONCLUSIONS

Though replication in larger and more diverse samples is needed, findings provide early support for the validity of the PARDI-AR-Q as a self-report measure for possible ARFID in clinical or research settings.

ODP370 Disconnect Between Hypothalamic-Pituitary-Adrenal Activity and Amygdala Activation Using Novel Neuroimaging Fear Paradigm in Youth With Avoidant/Restrictive Food Intake Disorder

Background

Avoidant/restrictive food intake disorder (ARFID) is characterized by restrictive eating patterns without shape or weight concerns, leading to nutritional deficits and psychosocial impairment. Three distinct phenotypes have been described that can co-occur: 1) sensory sensitivity, 2) lack of interest in eating or food, and 3) food avoidance due to fear of aversive consequences. Hyperactivation of a "defensive motive system", characterized by a neurocircuit activation of the amygdala and the hypothalamic-pituitary-adrenal (HPA) axis, could mediate fear/threat pathways in ARFID. We hypothesized that youth with ARFID would show amygdala hyperactivation in response to an ARFID-specific fear paradigm, and greater amygdala activation would be associated with higher levels of cortisol. Method76 youth with ARFID assessed using the Pica, ARFID and Rumination Disorder Interview and 27 healthy controls (HC) underwent functional MRI scanning (3T Siemens) during a novel visual fear task. Subjects viewed a series of developmentally appropriate images: ARFID-specific fear (e. g., a person vomiting or choking) and neutral (e. g., household items, geometric shapes). Serum cortisol was measured prior to the MRI in the late morning after a 2-hour fast. Amygdala activation was compared between ARFID and HC for the contrast ARFID-specific fear vs. neutral images using SPM12. For this contrast, beta values were extracted and correlated with fasting cortisol levels using Pearson's correlation coefficient.

Results

Groups did not differ for age, sex, or BMI z-score (ARFID mean (SD) age 16.5 (3.9) years, HC 17.8 (4. 0) years (p=0.14); ARFID 50% male, HC 42% male (p=0.66); ARFID BMI z-score -0.5 (1.7), HC 0. 0 (0.8) (p=0.15). In response to ARFID-specific fear vs. neutral images, both HC and ARFID exhibited increased activation in the bilateral amygdala (p<0. 05), however there were no significant differences in amygdala activation between ARFID vs. HC. Cortisol levels did not differ between groups (p=0.83). In the HC group, there was a positive correlation between amygdala activation in response to the contrast ARFID-specific fear vs. neutral images and cortisol levels (r=0.54, p=0. 02), which was absent in ARFID (r=-0. 02, p=0.88) (between-group difference p=0. 01).

Conclusion

Using a novel fMRI paradigm, our results show that images related to ARFID-specific fears elicit robust increases in amygdala activation across ARFID and HC subjects, but no between-group differences. While higher amygdala activation was associated with higher cortisol levels in HC, this relationship was absent in ARFID, suggesting a disconnect of amygdala response and basal HPA activation to fear inducing stimuli. Future research will be important to improve our understanding of endocrine modulation of the fear response and relationship to restrictive eating in ARFID.

Presentation: No date and time listed

PMON58 Endogenous Oxytocin Response to Food Intake in Avoidant/Restrictive Food Intake Disorder Compared to Healthy Controls

Context

In healthy individuals, serum levels of oxytocin, an anxiolytic hypothalamic-pituitary hormone involved in appetite regulation and response to stress, decrease post-prandially. Oxytocin response to a meal in Avoidant/Restrictive Food Intake Disorder (ARFID), a psychiatric disorder characterized by restrictive eating driven by lack of interest in food, sensory sensitivity, and/or fear of aversive consequences and associated with comorbid anxiety, is unknown. We compared the pattern of postprandial oxytocin levels in individuals with ARFID to healthy controls (HC). We hypothesized that overall oxytocin levels would be higher in ARFID vs HC as an adaptive response to stress.

Methods

109 participants (55 with ARFID and 54 HC) were instructed to eat a ∼400-kcal standardized mixed meal. Serum oxytocin was sampled fasting and 30, 60, and 120 minutes post-meal. Anxiety was assessed using the trait scale of the State-Trait Anxiety Inventory (STAI). All data are presented as mean±SEM. Multivariate regression analysis was used to control for confounding variables.

Results

Mean age did not differ across groups (ARFID: 16.9±0.5 and HC: 17.8±0.5 years, p=0.197). Mean body mass index percentile (BMIp) was lower in ARFID compared to HC (37.3±4.9 vs 53.7±2.9, respectively, p=0.004). Sex distribution differed between groups [ARFID: 27 (50%) males, 27 (50%) females vs HC: 15 (27%) males and 40 (73%) females, p=0.019)]. Anxiety symptoms were higher in ARFID compared to HC (38.5±1.8 vs 30.3±1.0, respectively, p=0.0007). By study design, quantity of food consumed did not differ across groups (p=0.238), however, ARFID participants ate a higher % of fat than HC (22.8±0.5 vs. 21.6±0.4, p=0.027). Mean oxytocin levels were higher in ARFID compared to HC at all time points (fasting: 1487±94 vs 1268±60 pg/mL, p=0.049; 30 min: 1477±86 vs 1202±48 pg/mL, p=0.006; 60 min: 1473±89 vs 1214±52 pg/mL, p=0.015; 120 min: 1470±102 vs 1253±50 pg/mL, respectively, p=0.056), and AUC (p=0.023). While mean oxytocin decreased postprandially as expected in HC (30 min p=0.028 and 60 min p=0.072), there was no postprandial change in oxytocin levels in ARFID from fasting to any postprandial timepoint (p≥0.746). Multivariate regression analysis revealed that both ARFID group (β=41,213, η²p = 0.084, p=0.004) and BMIp (β=779, η²p = 0.129, p<0.001) accounted for higher oxytocin levels irrespective of sex, fat intake and anxiety levels (R²=0.192).

Conclusions

This is the first study to determine the pattern of endogenous oxytocin secretion in response to a meal in a large group of individuals with ARFID. Mean oxytocin levels fasting and in response to a meal are higher in ARFID compared to HC, irrespective of sex, quantity of fat consumed, and anxiety symptoms. Unlike in healthy individuals, oxytocin levels in ARFID do not decrease in response to eating. These data suggest that dysregulated oxytocin secretion may play a role in the pathophysiology of ARFID.

Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

The factor structure and validity of a diagnostic interview for avoidant/restrictive food intake disorder in a sample of children, adolescents, and young adults

OBJECTIVE

There is a paucity of validated diagnostic interviews for avoidant/restrictive food intake disorder (ARFID) to aid identification and classification of cases for both clinical and research purposes. To evaluate the factor structure, construct validity, and criterion validity of the Pica ARFID and Rumination Disorder Interview (PARDI; ARFID module), we administered the PARDI to 129 children and adolescents ages 9-23 years (M = 16.1) with ARFID (n = 84), subclinical ARFID (n = 11), and healthy controls (n = 34).

METHOD

We used exploratory factor analysis to examine the factor structure of the PARDI in children, adolescents, and young adults with an ARFID diagnosis, the Kruskal-Wallis analysis of variance and Spearman correlations to test the construct validity of the measure, and non-parametric receiver operating characteristic curves to evaluate the criterion validity of the PARDI.

RESULTS

Exploratory factor analysis yielded a 3-factor structure: (1) concern about aversive consequences of eating, (2) low appetite/low interest in food, and (3) sensory sensitivity. Participants with ARFID demonstrated significantly higher levels of sensory sensitivity, low appetite/low-food interest, and concern about aversive consequences of eating symptoms relative to control participants. The construct validity for each PARDI subscale was supported and clinical cutoffs for the low appetite/low interest in food (1.1) and sensory sensitivity subscales (0.6) were established.

DISCUSSION

These data present evidence for the factor structure and validity of the PARDI diagnostic interview for diagnosing ARFID in children, adolescents, and young adults, supporting the use of this tool to facilitate ARFID clinical assessment and research.

PUBLIC SIGNIFICANCE

Due to the paucity of validated diagnostic interviews for avoidant/restrictive food intake disorder (ARFID), we evaluated the factor structure and validity of the Pica ARFID and Rumination Disorder Interview (ARFID module). Findings suggest that the interview assesses 3 components of ARFID: concern about aversive consequences of eating, low-appetite, and sensory sensitivity, and that clinical threshold scores on the latter two subscales can be used to advance ARFID assessment.

Differential comorbidity profiles in avoidant/restrictive food intake disorder and anorexia nervosa: Does age play a role?

OBJECTIVE

Research comparing psychiatric comorbidities between individuals with avoidant/restrictive food intake disorder (ARFID) and anorexia nervosa (AN) is limited. ARFID often develops in childhood, whereas AN typically develops in adolescence or young adulthood. Understanding how age may impact differential psychological comorbidity profiles is important to inform etiological conceptualization, differential diagnosis, and treatment planning. We aimed to compare the lifetime frequency of psychiatric comorbidities and suicidality between females with ARFID (n = 51) and AN (n = 40), investigating the role of age as a covariate.

METHOD

We used structured interviews to assess the comparative frequency of psychiatric comorbidities/suicidality.

RESULTS

When age was omitted from analyses, females with ARFID had a lower frequency of depressive disorders and suicidality compared to AN. Adjusting for age, only suicidality differed between groups.

DISCUSSION

This is the first study to compare comorbidities in a similar number of individuals with ARFID and AN, and a structured clinical interview to confer ARFID and comorbidities, covarying for age, and the first to compare suicidality. Although suicidality is at least three times less common in ARFID than AN, observed differences in other psychiatric comorbidities may reflect ARFID's relatively younger age of presentation compared to AN.

PUBLIC SIGNIFICANCE

Our results highlight that, with the exception of suicidality, which was three times less common in ARFID than AN irrespective of age, observed differences in psychiatric comorbidities in clinical practice may reflect ARFID's younger age at clinical presentation compared to AN.

Eighteen-month Course and Outcome of Adolescent Restrictive Eating Disorders: Persistence, Crossover, and Recovery

OBJECTIVE

In adults, low-weight restrictive eating disorders, including anorexia nervosa (AN), are marked by chronicity and diagnostic crossover from restricting to binge-eating/purging. Less is known about the naturalistic course of these eating disorders in adolescents, particularly atypical AN (atyp-AN) and avoidant/restrictive food intake disorder (ARFID). To inform nosology of low-weight restrictive eating disorders in adolescents, we examined outcomes including persistence, crossover, and recovery in an 18-month observational study.

METHOD

We assessed 82 women (ages 10-23 years) with low-weight eating disorders including AN (n = 40; 29 restricting, 11 binge-eating/purging), atyp-AN (n = 26; 19 restricting, seven binge-eating/purging), and ARFID (n = 16) at baseline, nine months (9 M; 75% retention), and 18 months (18 M; 73% retention) via semi-structured interviews. First-order Markov modeling was used to determine diagnostic persistence, crossover, and recovery occurring at 9 M or 18 M.

RESULTS

Among all diagnoses, the likelihood of remaining stable within a given diagnosis was greater than that of transitioning, with the greatest probability among ARFID (0.84) and AN-R (0.62). Persistence of BP and atypical presentations at follow-up periods was less stable (AN-BP probability 0.40; atyp-AN-R probability 0.48; atyp-AN-BP probability, 0.50). Crossover from binge-eating/purging to restricting occurred 72% of the time; crossover from restricting to binge-eating/purging occurred 23% of the time. The likelihood of stable recovery (e.g., recovery at both 9 M and 18 M) was between 0.00 and 0.36.

CONCLUSION

Across groups, intake diagnosis persisted in about two-thirds, and recovery was infrequent, underscoring the urgent need for innovative treatment approaches to these illnesses. Frequent crossover between AN and atyp-AN supports continuity between typical and atypical presentations, whereas no crossover to ARFID supports its distinction.

Neurobiology of Avoidant/Restrictive Food Intake Disorder in Youth with Overweight/Obesity Versus Healthy Weight

OBJECTIVE

Avoidant/restrictive food intake disorder (ARFID) occurs across the weight spectrum, however research addressing the coexistesnce of ARFID with overweight/obesity (OV/OB) is lacking. We aimed to establish co-occurrence of OV/OB and ARFID and to characterize divergent neurobiological features of ARFID by weight.

METHOD

Youth with full/subthreshold ARFID (12 with healthy weight [HW], 11 with OV/OB) underwent fasting brain fMRI scan while viewing food/non-food images (M age = 16.92 years, 65% female, 87% white). We compared groups on BOLD response to high-calorie foods (HCF) (vs. objects) in food cue processing regions of interest. Following fMRI scanning, we evaluated subjective hunger pre- vs. post-meal. We used a mediation model to explore the association between BMI, brain activation, and hunger.

RESULTS

Participants with ARFID and OV/OB demonstrated significant hyperactivation in response to HCF (vs. objects) in the orbitofrontal cortex (OFC) and anterior insula compared with HW participants with ARFID. Mediation analysis yielded a significant indirect effect of group (HW vs. OV/OB) on hunger via OFC activation (effect = 18.39, SE = 11.27, 95% CI [-45.09, -3.00]), suggesting that OFC activation mediates differences in hunger between ARFID participants with HW and OV/OB.

CONCLUSIONS

Compared to youth with ARFID and HW, those with OV/OB demonstrate hyperactivation of brain areas critical for the reward value of food cues. Postprandial changes in subjective hunger depend on BMI and are mediated by OFC activation to food cues. Whether these neurobiological differences contribute to selective hyperphagia in ARFID presenting with OV/OB and represent potential treatment targets is an important area for future investigation.

Food neophobia as a mechanism of change in video-delivered cognitive-behavioral therapy for avoidant/restrictive food intake disorder: A case study

OBJECTIVE

The mechanisms through which cognitive-behavioral therapies (CBTs) for avoidant/restrictive food intake disorder (ARFID) may work have yet to be elucidated. To inform future treatment revisions to increase parsimony and potency of CBT for ARFID (CBT-AR), we evaluated change in food neophobia during CBT-AR treatment of a sensory sensitivity ARFID presentation via a single case study.

METHOD

An adolescent male completed 21, twice-weekly sessions of CBT-AR via live video delivery. From pre- to mid- to post-treatment and at 2-month follow-up, we calculated percent change in food neophobia and ARFID symptom severity measures. Via visual inspection, we explored trajectories of week-by-week food neophobia in relation to clinical improvements (e.g., when the patient incorporated foods into daily life).

RESULTS

By post-treatment, the patient achieved reductions across food neophobia (45%), and ARFID severity (53-57%) measures and no longer met criteria for ARFID, with sustained improvement at 2-month follow-up. Via visual inspection of week-by-week food neophobia trajectories, we identified that decreases occurred after mid-treatment and were associated with incorporation of a food directly tied to the patient's main treatment motivation.

DISCUSSION

This study provides hypothesis-generating findings on candidate CBT-AR mechanisms, showing that changes in food neophobia were related to food exposures most connected to the patient's treatment motivations.

PUBLIC SIGNIFICANCE

Cognitive-behavioral therapies (CBTs) can be effective for treating avoidant/restrictive food intake disorder (ARFID). However, we do not yet have evidence to show how they work. This report of a single patient shows that willingness to try new foods (i.e., food neophobia), changed the most when the patient experienced a clinical improvement most relevant to his motivation for seeking treatment.

Elevated Fasting Satiety-Promoting Cholecystokinin (CCK) in Avoidant/Restrictive Food Intake Disorder Compared to Healthy Controls

Objective: Avoidant/restrictive food intake disorder (ARFID) is characterized by food avoidance or dietary restriction not primarily motivated by body weight/shape concerns. Individuals with ARFID can report early satiation, post-prandial fullness, and high intermeal satiety, but whether these symptoms are related to differences in the biology underlying appetite regulation is unknown. In male and female children and adolescents, we hypothesized that fasting levels of cholecystokinin (CCK), a satiety hormone, would be elevated in participants with ARFID (full or subthreshold) versus healthy controls (HCs). Within the ARFID group, we also explored the relations of CCK with weight status, subjective appetite ratings, and ARFID severity and phenotypes. Methods: A total of 125 participants (83 with full/subthreshold ARFID (per DSM-5) and 42 HCs, aged 10.2-23.7 years; 61% female; July 2014-December 2019) underwent fasting blood draws for CCK, completed self-report measures assessing subjective state and trait appetite ratings, and completed a semistructured interview assessing ARFID severity. Results: Fasting CCK was higher in those with full/subthreshold ARFID versus HCs with a large effect (F₁ = 25.0, P < .001, η_p² = 0.17), controlling for age, sex, and body mass index (BMI) percentile. Within the ARFID group, CCK was not significantly related to BMI percentile, subjective appetite ratings, or ARFID characteristic measures. Conclusions: CCK may contribute to etiology and/or maintenance of ARFID, as children and adolescents with heterogeneous presentations of avoidant/restrictive eating appear to show elevated fasting levels compared to healthy youth. Further research is needed to understand relations between CCK and appetite, weight, and eating behavior in ARFID.

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.

Anhedonia in eating disorders: A meta-analysis and systematic review

OBJECTIVE

Anhedonia, or loss of pleasure, is related to deficits in reward processing across a variety of psychiatric disorders. In light of research suggesting abnormal reward processing in eating disorders (EDs), the study of anhedonia in EDs may yield important insights into the role of reward in eating pathology. This meta-analysis and review aimed to provide both a quantitative and qualitative synthesis of the existing literature on this topic.

METHOD

We conducted this research (or these meta-analyses) according to PRISMA guidelines. We searched four databases for both peer-reviewed and unpublished literature, and included studies only if a self-report or clinical interview measure of anhedonia was administered to a sample with an ED diagnosis.

RESULTS

We included 21 studies in the systematic review, and 10 studies in two meta-analyses that compared anhedonia between ED and control samples (n = 9 studies) and within different ED diagnoses (n = 5 studies). Meta-analyses revealed that anhedonia was significantly higher in ED groups compared to healthy controls, but there was no significant difference in anhedonia between ED diagnostic groups. A qualitative review of the literature also suggested that anhedonia may be correlated with increased ED symptom severity.

DISCUSSION

Findings indicated that anhedonia is elevated in EDs and may be a relevant treatment target. Future research should examine how self-reported anhedonia may correlate with components of reward processing in EDs in order to improve theoretical models as well as targeted interventions.

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).

Open science practices for eating disorders research

This editorial seeks to encourage the increased application of three open science practices in eating disorders research: Preregistration, Registered Reports, and the sharing of materials, data, and code. For each of these practices, we introduce updated International Journal of Eating Disorders author and reviewer guidance. Updates include the introduction of open science badges; specific instructions about how to improve transparency; and the introduction of Registered Reports of systematic or meta-analytical reviews. The editorial also seeks to encourage the study of open science practices. Open science practices pose considerable time and other resource burdens. Therefore, research is needed to help determine the value of these added burdens and to identify efficient strategies for implementing open science practices.

Comprehensive Cognitive-Behavioral Interventions Augment Diaphragmatic Breathing for Rumination Syndrome: A Proof-of-Concept Trial

BACKGROUND

Rumination syndrome (RS) is often treated in medical settings with 1-2 sessions of diaphragmatic breathing to target reflexive abdominal wall contraction in response to conditioned cues (e.g., food). However, many patients remain symptomatic and require additional behavioral interventions.

AIMS

In an attempt to augment diaphragmatic breathing with additional interventions, we tested the proof-of-concept of a comprehensive Cognitive-Behavioral Therapy (CBT) for RS.

METHODS

In an uncontrolled trial, adults with RS completed a 5-8 session CBT protocol, delivered by one of two psychology behavioral health providers. CBT included two main phases: awareness training and diaphragmatic breathing (Phase 1) and modularized interventions chosen by the therapist and patient to target secondary maintenance mechanisms (Phase 2). At pre-treatment, post-treatment, and 3-month follow-up, participants completed a semi-structured interview on RS symptoms with an independent evaluator.

RESULTS

Of 10 eligible individuals (ages 20-67 years, 50% female) offered treatment, all 10 initiated treatment and eight completed it. All participants endorsed high treatment credibility at Session 1. Permutation-based repeated measures ANOVA showed participants achieved large reductions in regurgitations across treatment [F(1,7) = 17.7, p = .007, η _p²  = .69]. Although participants reduced regurgitations with diaphragmatic breathing during Phase 1, addition of other CBT strategies in Phase 2 produced further large reductions [F(1,7) = 6.3, p = .04, η _p²  = .47]. Of eight treatment completers, treatment gains were maintained at 3-month follow-up for n = 6.

CONCLUSIONS

Findings provide evidence of feasibility, acceptability, and proof-of-concept for a comprehensive CBT for RS that includes interventions in addition to diaphragmatic breathing to target secondary maintenance mechanisms. Randomized controlled trials are needed.

Meta-analysis of structural MRI studies in anorexia nervosa and the role of recovery: a systematic review protocol

BACKGROUND

Anorexia nervosa (AN) is associated with structural brain abnormalities. Studies have reported less cerebral tissue and more cerebrospinal fluid (CSF) in individuals with AN relative to healthy controls, although findings are variable and inconsistent due to variations in sample size, age, and disease state (e.g., active AN, weight-recovered AN). Further, it remains unclear if structural brain abnormalities observed in AN are a consequence of specific brain pathologies or malnutrition, as very few longitudinal neuroimaging studies in AN have been completed.

METHODS

To overcome this issue, this comprehensive meta-analysis will combine region-of-interest (ROI) and voxel-based morphometry (VBM) approaches to understand how regional and global structural brain abnormalities differ among individuals with AN and healthy controls (HCs). Additionally, we aim to understand how clinical characteristics and physiological changes during the course of illness, including acute illness vs. weight recovery, may moderate these structural abnormalities. We will create an online database of studies that have investigated structural brain abnormalities in AN. Data will be reviewed independently by two members of our team using MEDLINE databases, Web of Science, PsycINFO, EMBASE, and CINAHL. We will conduct ROI and VBM meta-analysis using seed-based d mapping in AN and HCs. We will include all studies that include structural neuroimaging of individuals with AN (both acute and weight-recovered) and HCs between January 1997 and 2020.

DISCUSSION

This systematic review will assess the effects of AN compared to HC on brain structure. Futhermore, it will explore the role of acute AN and weight-recovered AN on brain structure. Findings will help researchers and clinicians to better understand the course of illness in AN and the nature of recovery, in terms of weight, malnutrition, and the state of the brain.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020180921.

A Moving Target: How We Define Avoidant/Restrictive Food Intake Disorder Can Double Its Prevalence

Objective: The DSM-5 criteria for avoidant/restrictive food intake disorder (ARFID) include ambiguities. Diagnostic criteria that allow for clinical judgment are essential for clinical practice. However, ambiguities can have major implications for treatment access and comparability and generalizability of research studies. The purpose of this study was to determine the degree to which distinct operationalizations of the diagnostic criteria for ARFID contribute to differences in the frequency of individuals who are eligible for the ARFID diagnosis. Methods: Because criteria B, C, and D are rule-outs, we focused on criterion A, identified 19 potential operational definitions, and determined the extent to which these different methods impacted the proportion of individuals who met criteria for ARFID in a sample of children, adolescents, and young adults (n = 80; September 2016-February 2020) enrolled in an avoidant/restrictive eating study. Results: Within each criterion, the proportion of individuals meeting diagnostic criteria differed significantly across the methodologies (all P values < .008). Using the strictest definition of each criterion, 50.0% (n = 40) of participants met criteria for ARFID. In contrast, under the most lenient definition of each criterion, the number nearly doubled, resulting in 97.5% (n = 78) meeting ARFID criteria. Conclusions: Comparison of diagnostic definitions for ARFID among children, adolescents, and young adults confirmed a broad range of statistically distinct proportions within a single sample. Our findings support the need for additional contextual support and consensus among disciplines on operationalization in both research and clinical settings.

Cognitive-behavioral therapy for adults with avoidant/restrictive food intake disorder

There are currently no evidence-based treatments for adults with avoidant/restrictive food intake disorder (ARFID). The purpose of this study was to evaluate the acceptability, feasibility, and proof-of-concept of cognitive-behavioral therapy for ARFID (CBT-AR) for adults. Males and females (ages 18–55 years) were offered 20–30 outpatient sessions of CBT-AR delivered by one of five therapists. Of 18 eligible adults offered CBT-AR, 15 chose to participate and 14 completed treatment. All patients endorsed high ratings of treatment credibility and expected improvement after the first session, and 93% of completers provided high ratings of satisfaction at the conclusion of treatment. Therapists rated the majority (80%) of patients as “much improved” or “very much improved.” Based on intent-to-treat analyses, ARFID severity on the Pica, ARFID, and Rumination Disorder Interview (PARDI) showed a large and significant decrease from pre- to post-treatment; and patients incorporated a mean of 18.0 novel foods. The underweight subgroup (n = 4) gained an average of 11.38 pounds, showing a large and significant increase in mean BMI from the underweight to the normal-weight range. At post-treatment, 47% of patients no longer met criteria for ARFID. To our knowledge, this is the first prospective treatment study of ARFID in adults. The findings of this study provide preliminary evidence of feasibility, acceptability, and proof-of-concept of CBT-AR for heterogeneous presentations of ARFID in adults. Randomized controlled trials are needed to confirm these findings. ClinicalTrials.gov Identifier: NCT02963220.

Detection and characteristics of rumination syndrome in patients presenting for gastric symptom evaluation

BACKGROUND

Rumination syndrome involves effortless, repeated regurgitation, and can overlap with other upper gastrointestinal disorders, including gastroparesis. To inform better diagnostic detection of rumination, we aimed to (1) identify frequency and characteristics of rumination in patients presenting for gastric symptom evaluation; and (2) assess demographic and clinical characteristics that could differentiate those with versus those without rumination.

METHODS

Consecutively referred patients to two tertiary academic centers for gastric symptom specialty evaluation were included (N = 242). We obtained demographic information, gastric emptying scintigraphy, upper gastrointestinal symptoms using the Patient Assessment of Upper Gastrointestinal Symptoms (PAGI-SYM), and Rome IV-based rumination questionnaire.

KEY RESULTS

Thirty-one of the 242 (12.8%) patients met criteria for rumination syndrome, of which 48% reported associated psychosocial impairment. Comparing those with rumination and those without, there were no differences in race, gender, frequency of diabetes, or frequency of gastroparesis. The median PAGI-SYM score for rumination patients was higher than for those without (3.03 vs. 2.55; unadjusted p = 0.043, adjusted p = 0.30). This was largely driven by increased heartburn/regurgitation subscale scores (2.71 vs. 1.57, unadjusted p = 0.0067, adjusted p = 0.046), itself influenced by elevated daytime regurgitation/reflux (3.0 vs. 2.0; unadjusted p = 0.007, adjusted p = 0.048). There were no significant differences on the remaining PAGI-SYM subscales.

CONCLUSIONS AND INFERENCES

Rumination syndrome determined by Rome IV criteria was present in 12.8% of patients presenting for gastric symptom evaluation. Higher self-report PAGI-SYM heartburn/regurgitation subscale scores, particularly daytime regurgitation/reflux symptoms, were the only parameters that distinguished rumination. The PAGI-SYM heartburn/regurgitation subscale could be used to screen for rumination, in addition to GERDAQ6.

Cognitive rigidity and heightened attention to detail occur transdiagnostically in adolescents with eating disorders

Cognitive inflexibility and attention to detail bias represent a promising target in eating disorder (ED) treatment. While prior research has found that adults with eating disorders exhibit significant cognitive inflexibility and heightened attention to detail, less is known about these cognitive impairments among adolescents, and across EDs transdiagnostically. To address this gap, adolescent females (N = 143) from a residential ED program with anorexia nervosa, bulimia nervosa, or other specified feeding or eating disorder completed the Detail and Flexibility Questionnaire (DFlex) and measures of ED and general psychopathology. Transdiagnostically, adolescents with EDs scored higher than an archival sample of healthy control adolescents on both cognitive rigidity (p < .001; Cohen's d = 1.92) and attention to detail (p < .001; Cohen's d = 1.16). These cognitive impairments were significantly associated with severity of eating pathology, and these relationships existed independent of age, duration of illness, or body mass index (BMI). Our findings suggest cognitive inflexibility and heightened attention to detail occur transdiagnostically in adolescents with eating disorders and are unlikely to be a scar of the disorder. Future prospective research is needed to determine whether these cognitive styles represent an endophenotype of eating disorders.

Ghrelin and PYY in low-weight females with avoidant/restrictive food intake disorder compared to anorexia nervosa and healthy controls

BACKGROUND

Avoidant/restrictive food intake disorder (ARFID) is characterized by restrictive eating and failure to meet nutritional needs but is distinct from anorexia nervosa (AN) because restriction is not motivated by weight/shape concerns. We examined levels of orexigenic ghrelin and anorexigenic peptide YY (PYY) in young females with ARFID, AN and healthy controls (HC).

METHODS

94 females (22 low-weight ARFID, 40 typical/atypical AN, and 32 HC ages 10-22 years) underwent fasting blood draws for total ghrelin and total PYY. A subset also provided blood 30, 60 and 120 min after a standardized meal.

RESULTS

Females with ARFID ate less than those with AN or HC (ps<0.012); were younger (14.4 ± 3.2 years) than those with AN (18.9 ± 3.1 years) and HC (17.4 ± 3.1 years) (ps<0.003) and at a lower Tanner stage (3.1 ± 1.5) than AN (4.5 ± 1.1;) and HC (4.4 ± 1.1; ps<0.005), but did not differ in BMI percentiles or BMI Z-scores from AN (ps>0.44). Fasting and postprandial ghrelin were lower in ARFID versus AN (ps≤.015), but not HC (ps≥0.62). Fasting and postprandial PYY did not differ between ARFID versus AN or HC (ps≥0.13); ARFID did not demonstrate the sustained high PYY levels post-meal observed in those with AN and HC. Secondary analyses controlling age or Tanner stage and calories consumed showed similar results. Exploratory analyses suggest that the timing of the PYY peak in ARFID is earlier than HC, showing a peak PYY level 30 min post-meal (p = .037).

CONCLUSIONS

ARFID and AN appear to have distinct patterns of secretion of gut-derived appetite-regulating hormones that may aid in differential diagnosis and provide new treatment targets.

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

OBJECTIVE

Little research exists on Rome IV disorders of gut-brain interaction (DGBI; formerly called functional gastrointestinal disorders) in outpatients with eating disorders (EDs). These data are particularly lacking for avoidant/restrictive food intake disorder (ARFID), which shares core features with DGBI. We aimed to identify the frequency and nature of DGBI symptoms among outpatients with EDs.

METHOD

Consecutively referred pediatric and adult patients diagnosed with an ED (n = 168, 71% female, ages 8-76 years) in our tertiary care ED program between March 2017 and July 2019 completed a modified Rome IV Questionnaire for DGBI and psychopathology measure battery.

RESULTS

The majority (n = 122, 72%) of participants reported at least one bothersome gastrointestinal symptom. Sixty-six (39%) met criteria for a DBGI, most frequently functional dyspepsia-post-prandial distress syndrome subtype (31%). DGBI were surprisingly less frequent among patients with ARFID (30%) versus EDs that are associated with shape or weight concerns (45%; X² [1] = 3.61, p = .058, Cramer's V = .147). Among those with ARFID, DGBI presence was associated with the fear of aversive consequences prototype and multiple comorbid prototype presence.

DISCUSSION

We demonstrated notable overlap between DGBI and EDs, particularly post-prandial distress symptoms. Further research is needed to examine if gastrointestinal symptoms predict or are a result of greater ED pathology, including ARFID prototypes.

Network Analysis of Posttraumatic Stress and Eating Disorder Symptoms in a Community Sample of Adults Exposed to Childhood Abuse

Posttraumatic stress disorder (PTSD) and eating disorders (EDs) are individually debilitating and highly comorbid conditions. Childhood abuse is a prominent risk factor for PTSD and ED symptoms both individually and as a comorbid syndrome (PTSD-ED). There may be a functional association between comorbid PTSD-ED symptoms whereby disordered eating behaviors are used to avoid trauma-related thoughts and feelings. The current study used a network analytic approach to examine key associations between PTSD and ED symptom subscales (i.e., PCL-5 and EPSI, respectively) in a community sample of 120 adults who endorsed at least one experience of childhood abuse (i.e., physical, sexual, or emotional abuse; witnessing domestic violence). Participants completed an anonymous online survey using Amazon's Mechanical Turk Prime. We used three network analysis indices (i.e., strength centrality, key players, and bridge symptoms) to identify symptoms that may maintain the comorbid PTSD-ED network. The results indicated that reexperiencing symptoms had the highest strength centrality in the PTSD-ED network and bridged the PTSD and ED clusters. For ED, cognitive restraint was a bridge to all PTSD symptoms. Hyperarousal, negative alterations in cognitions and mood (NACM), and purging were key players, indicating they are integral to the network structure. If replicated in prospective studies, these results may indicate that reexperiencing and cognitive restraint are core drivers of PTSD-ED comorbidity, whereas hyperarousal, NACM, and purging may be downstream consequences maintaining the comorbid condition. Concurrent treatments that address PTSD and ED symptoms simultaneously may result in the best outcomes.

Higher Peptide YY Levels Are Associated With Lower Bone Mineral Density in Low Weight Adolescent Girls With Avoidant/Restrictive Food Intake Disorder

Background: Avoidant/Restrictive Food Intake Disorder (ARFID) is a condition characterized by lack of interest in eating or food, sensory sensitivity, and/or fear of aversive consequences of eating; as opposed to the body image disturbance and fear of weight gain that characterize anorexia nervosa (AN). While appetite regulating hormones and their associations with bone mineral density (BMD) have been well studied in AN, little is known regarding BMD and its association with appetite regulating hormones in ARFID. Peptide YY (PYY), a gut derived anorexigenic hormone, acts via the Y2 receptor to inhibit osteoblastic activity in mammals. In AN, levels of PYY are higher than in healthy controls (HC) and are negatively associated with BMD. We hypothesized that similar to AN, low-weight female adolescents with ARFID would have lower BMD and higher PYY levels than in HC and that PYY levels would be inversely associated with BMD.

Methods: We studied 24 adolescent females (10 low weight with ARFID and 14 HC). BMD variables were measured by Dual-Energy X-ray Absorptiometry. We performed cross sectional analysis to compare BMD and fasting PYY levels between low weight ARFID and HC and to determine the relationship between BMD and PYY levels.

Results: ARFID and HC were 15.1±2.9 (mean ± SEM) and 17.1±3.8 years old, respectively (p=0.178), with mean BMI Z-scores of -1.74±0.88 kg/m² and 0.24±0.51 kg/m², respectively (p<0.0001). Total body BMD Z-scores were significantly lower in ARFID (-1.59±1.19, n=10) compared to HC (-0.41±1.11, n=14) (p=0.022), and lumbar BMD Z-scores were numerically lower in ARFID (-1.13±1.40, n=9) vs. HC (-0.44±0.86, n=14) (p=0.212). Mean PYY levels trended higher in ARFID (104.6±39.9 pg/ml, n=8) vs. HC (71.4±24.5 pg/ml, n=9) (p=0.054). In a combined analysis of participants with ARFID and HC, PYY levels were negatively correlated with lumbar BMD and BMD Z-scores (r=-0.52, p=0.038 and r=-0.54 p=0.031, n=16). In multivariable regression analysis, PYY remained a primary determinant of lumbar BMD after adjusting for age and height (p=0.035, β= -0.36) and a borderline significant predictor of lumbar BMD Z-scores after adjusting for height (p=0.064, β=-0.5). Similar associations were noted within the ARFID group alone, with PYY being a significant predictor of lumbar BMD (p=0.031, β=-0.97) after adjusting for age and height.

Conclusion: Female adolescents with low-weight ARFID have lower BMD and a trend toward higher levels of PYY compared with HC. Increased PYY levels may contribute to the lower BMD observed in ARFID. These findings are an initial step in understanding the neuroendocrine dysregulation in low weight adolescents with ARFID, which may predict bone outcomes in this condition.

Neurobiology of Avoidant/Restrictive Food Intake Disorder in Youth With Overweight/Obesity Versus Healthy Weight

Objective: Avoidant/restrictive food intake disorder (ARFID) occurs across the weight spectrum, however research addressing the coexistence of ARFID with overweight/obesity (OV/OB) is lacking. We aimed to establish co-occurrence of OV/OB and ARFID and to characterize divergent neurobiological features of ARFID by weight.

Method: Youth with full/subthreshold ARFID (11 with healthy weight [HW], 12 with OV/OB) underwent fasting brain fMRI scan while viewing food/non-food images (M age = 16.92 years, 65% female, 87% white). We compared groups on BOLD response to high-calorie foods (HCF) (vs. objects) in food cue processing regions of interest. Following fMRI scanning, we evaluated subjective hunger pre- vs. post-meal. We used a mediation model to explore the association between BMI, brain activation and hunger.

Results: Participants with ARFID and OV/OB demonstrated significant hyperactivation in response to HCF (vs. objects) in the orbitofrontal cortex (OFC) and anterior insula compared with HW subjects with ARFID. Mediation analysis yielded a significant indirect effect of group (HW vs. OV/OB) on hunger via OFC activation (effect=18.39, SE=11.27, 95% CI [-45.09, -3.00]), suggesting that OFC activation mediates differences in hunger between ARFID participants with HW and OV/OB.

Conclusions: Compared to youth with ARFID and HW, those with OV/OB demonstrate hyperactivation of brain areas critical for reward value of food cues. Postprandial changes in subjective hunger depend on BMI and are mediated by OFC activation to food cues. Whether these neurobiological differences contribute to selective hyperphagia in ARFID presenting with OV/OB and represent potential treatment targets is an important area for future investigation.

Olfactory Performance in Youth With Full and Subthreshold Avoidant/Restrictive Food Intake Disorder

Background: Avoidant/restrictive (A/R) food intake disorder (ARFID) is characterized by restrictive eating defined by lack of interest in food, sensory sensitivity, and/or fear of aversive consequences of eating resulting in a failure to meet adequate nutritional and/or energy needs. The complex psychopathology that differentiates ARFID from other eating disorders highlights the need to explore the role of sensory systems in disease etiology. Olfaction has an important role in eating behavior. Specifically, olfactory dysfunction is associated with decreased food intake and appetite. Olfactory performance and associated clinical characteristics have yet to be examined in individuals with ARFID. We hypothesized that higher levels of PYY, which signals satiety, would be associated with poorer olfactory performance; whereas greater food fussiness and A/R eating severity would be associated with stronger olfactory performance. Methods: We evaluated a cross-sectional sample of children and adolescents with full and subthreshold ARFID (n=82, 46.2% female, mean age 15.8±3.8). We measured olfactory performance with the Sniffin’ Sticks test (Burghardt®, Wedel, Germany) which captures odor discrimination, odor identification, and odor threshold. Higher scores on all three indices represent stronger olfactory performance. We also measured fasting serum PYY; severity of A/R eating on the Pica, ARFID and Rumination Disorder Interview (PARDI); and food fussiness as a measure of food-related sensory sensitivity on the Adult Eating Behavior Questionnaire. Statistical analyses included T-test and spearman’s correlations. Results: Greater fasting serum PYY levels were associated with significantly poorer performance on the odor threshold test (r=-0.4, p=0.003). Greater severity of A/R eating (r=-0.3 p=0.008) and food fussiness (r=-0.2, p=0.03) were both associated with significantly poorer performance on the odor discrimination test. Conclusions: As predicted, we found that higher levels of PYY were associated with poorer olfactory performance in youth with full and subthreshold ARFID. However, contrary to hypotheses, we found that greater food fussiness and severity of A/R eating were associated with poorer olfactory performance. Future research should investigate whether high levels of PYY and poor olfactory performance are causes, consequences, or correlates of A/R eating.