Prospective Two-Year Course and Predictors of Outcome in Avoidant/Restrictive Food Intake Disorder.

OBJECTIVE: To evaluate the 2-year course and outcomes of full and subthreshold avoidant/restrictive food intake disorder (ARFID) in youth ages 9-23 at baseline using a prospective longitudinal design to characterize the remission and persistence of ARFID, evaluate diagnostic crossover, and identify predictors of outcome. We hypothesized that greater severity in each ARFID profile - sensory sensitivity, fear of aversive consequences, and lack of interest - would predict greater likelihood of illness persistence, controlling for age, sex, BMI percentile, ARFID treatment status, and baseline diagnosis. METHOD: We followed participants (N = 100; ages 9-23 years; 49% female, 91% White) over two years. We used the Pica, ARFID, and Rumination Disorder Interview across three time points (Baseline, Year 1, Year 2) to measure the severity of each ARFID profile and evaluate illness persistence or remission, and the Eating Disorder Assessment for DSM-5 to evaluate diagnostic crossover. RESULTS: Across the 2-year follow-up period, half the sample persisted with their original diagnosis, and 3% of participants experienced diagnostic shift to anorexia nervosa. Greater severity in the sensory sensitivity and lack of interest profiles was associated with higher likelihood of ARFID persistence at Year 1 only; greater severity in the fear of aversive consequences profile was associated with higher likelihood of ARFID remission at Year 2 only. CONCLUSION: Findings underscore the distinctiveness of ARFID from other eating disorders and emphasize its persistence over 2 years. Results also highlight the predictive validity and prognostic value of ARFID profiles (i.e., sensory sensitivity, fear of aversive consequences, lack of interest).

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.

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.

Avoidant/restrictive food intake disorder (ARFID) and anorexia nervosa (AN) are both restrictive eating disorders. However, the reasons for restricting food intake differ between the two diagnoses. A key question in further understanding similarities and differences between ARFID and AN is to understand whether individuals with these disorders process information and make decisions in similar or distinct ways. When humans decide between two different outcomes (e.g., a smaller immediate or a larger delayed reward), outcomes decrease in their value the farther in the future we expect to receive them (delay discounting). Individuals with AN exhibit a reduced discounting of future outcomes, which makes them more likely to forego immediate gratification for later rewards. However, whether this holds true for individuals with ARFID too (or whether they show the opposite or no bias) is unknown. Our investigation is the first to compare delay discounting between individuals with ARFID, AN, and healthy controls (HC). Our results show that individuals with ARFID show more delay discounting than those with AN, with no difference from HC. Knowing how rewards are being chosen and decisions made (and knowing differences between diagnoses) will be helpful in further optimizing and tailoring treatments for restrictive eating disorders.

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.

Individuals with eating disorders often report elevated anhedonia, or an inability to experience pleasure. Past research on pleasure in eating disorders has focused primarily on individuals with anorexia nervosa and bulimia nervosa, and it is unclear whether people with other eating disorders also experience lower pleasure than healthy individuals. In the current study, we measured anticipatory pleasure (looking forward to something enjoyable) and consummatory pleasure (enjoying a pleasant stimulus) in a sample with avoidant/restrictive food intake disorder (ARFID) and healthy controls. We also repeated our analyses after removing food-related items from the scale assessing pleasure. The ARFID group scored lower on both dimensions of pleasure than controls, but this difference was primarily due to greater depression symptoms and the presence of food-related items in the pleasure questionnaire. Within the ARFID sample, individuals with more severe ARFID reported less anticipatory pleasure, even after removing questions about enjoyment of food. Lower anticipatory pleasure was especially characteristic of the lack of interest in eating phenotype of ARFID. These results suggest that ARFID severity, lack of interest in eating, and depression contribute to low pleasure in this population.

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 (ß = -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.

Avoidant/restrictive food Intake disorder (ARFID) is a condition characterized by lack of interest in eating/food, sensory sensitivity and/or fear of aversive consequences of eating. It is associated with low weight and undernutrition, which can lead to medical complications. Specifically, low weight in patients with ARFID raises concerns of impaired bone health. In this study, we compared bone mineral density (BMD), a measure of bone health, in 14 low-weight females with ARFID and 20 healthy females 10­23 years old. We also examined the association between BMD and peptide YY (PYY), a hormone that induces satiety and inhibits bone formation. A strong negative association between bone health and PYY was previously reported in females with anorexia nervosa. Thus, we hypothesized a similar association in low weight females with ARFID. We found that BMD may be lower in low-weight females with ARFID than in healthy females and that higher PYY levels are associated with lower BMD at some but not all sites. We concluded that bone health may be a concern in low-weight females with ARFID. This finding is important as low BMD raises concerns for increased fracture risk, which in turn could have a detrimental effect on quality of life.

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.

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, ß = -0.27, P = .024; BAI/BAI-Y T scores, ß = -0.26, P = .034; LSAS, ß = -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.

Acculturation and eating disorders: a systematic review.

PURPOSE: Acculturation, or the dual process of cultural change that takes place due to the interaction between two or more cultural identities, may contribute to the susceptibility of developing an eating disorder (ED). We conducted a systematic review exploring the relationship between acculturation-related constructs and ED pathology. METHODS: We searched the PsychINFO and Pubmed/Medline databases up to December 2022. Inclusion criteria were: (1) having a measure of acculturation or related constructs; (2) having a measure of ED symptoms; and (3) experiencing cultural change to a different culture with Western ideals. 22 articles were included in the review. Outcome data were synthesized by narrative synthesis. RESULTS: There was variability in the definition and measure of acculturation in the literature. Overall, acculturation, culture change, acculturative stress, and intergenerational conflict were associated with ED behavioral and/or cognitive symptoms. However, the nature of the specific associations differed depending on the specific acculturation constructs and ED cognitions and behaviors measured. Furthermore, cultural factors (e.g., in-group vs. out-group preferences, generational status, ethnic group, gender) impacted the relationship between acculturation and ED pathology. DISCUSSION: Overall, this review highlights the need for more precise definitions of the different domains of acculturation and a more nuanced understanding of the specific relationship between various acculturation domains and specific ED cognitions and behaviors. Most of the studies were conducted in undergraduate women and in Hispanic/Latino samples, limiting generalizability of results. LEVEL OF EVIDENCE: Level V, Opinions of respected authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.

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.

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.