Casey MacDermod

Objective: Avoidant/restrictive food intake disorder (ARFID) occurs across the lifespan and body mass index (BMI) spectrum, yet little is known about how ARFID presents across BMI strata in adults. This study evaluated measurement invariance of the Nine‐Item ARFID Screen (NIAS) across BMI groups and examined differences in ARFID symptoms and clinical features. Method: Adults ( N = 3118) from the ARFID Genes and Environment (ARFID‐GEN) study completed self‐report measures, including the NIAS and the Pica, ARFID, and Rumination Disorder Interview ARFID Questionnaire. Structural equation and generalized linear models evaluated NIAS measurement invariance across BMI groups and assessed group differences in ARFID symptom dimensions and clinical features. Results: Almost half of the sample presented with overweight or obesity. Nutritional deficiency was more often reported among higher BMI groups, and psychosocial impairment did not differ significantly across strata. Measurement invariance was supported for several BMI comparisons, including normal weight versus overweight, normal weight versus obesity, and overweight versus obesity. In pairwise comparisons between invariant groups, picky eating was elevated in both underweight and obesity groups, while low appetite and fear were higher among adults with underweight. Discussion: Findings indicate that ARFID occurs across the adult BMI spectrum and that NIAS scores can be compared across most BMI groups, apart from highly discrepant groups. Results highlight that ARFID dimensions vary across BMI groups and that ARFID is not limited to traditionally low‐weight presentations. Continued research is needed to characterize ARFID across the BMI spectrum, particularly among higher‐BMI adults, who represent a meaningful proportion of those affected.

Objective: According to DSM‐5‐TR, avoidant/restrictive food intake disorder (ARFID) cannot be diagnosed alongside anorexia nervosa (AN), bulimia nervosa (BN), or any other body image disturbance. This does not accurately reflect real‐world symptomatology and recent research, indicating the potential need to revise DSM‐5‐TR Criteria. We investigated the co‐occurrence of weight‐ and/or shape‐motivated restriction (WSR) in adults who screened positive for ARFID, providing evidence to inform such changes. Method: The sample comprised 5747 adults who consented to participate in the ARFID‐Genes and Environment (ARFID‐GEN) research study, screened positive for ARFID on the NIAS and PARDI‐AR‐Q, and completed the EDE‐Q. We placed our participants into four groups: groups one and two screened positive for AN (ARFID‐AN; n = 147) or BN (ARFID‐BN; n = 193), group three endorsed WSR without meeting AN or BN criteria (ARFID‐WSR; n = 2159), and group four endorsed ARFID symptoms only (ARFID‐nWSR; n = 3248). We used generalized linear models to test group differences on the NIAS, PARDI‐AR‐Q, and EDE‐Q. Results: Where significant differences were present, ARFID‐nWSR demonstrated lower scores than all other groups across ARFID dimensions on the NIAS and PARDI‐AR‐Q, and lower odds of meeting DSM‐5‐TR Criteria A1 to A3 (i.e., weight loss; nutritional deficiencies; dependence on nutritional supplements). Discussion: These findings indicate a mixed phenotype with features of both ARFID and WSR associated with more severe ARFID symptomatology. The DSM‐5‐TR Criteria may not capture complex real‐world symptomatology in adults with probable ARFID, potentially precluding those with the most severe symptoms from receiving accurate diagnoses and appropriate care.

We examined associations between potentially traumatic events (PTEs) and lifetime eating disorders (EDs) in the Eating Disorders Genetics Initiative-Mexico [EDGI-MX; N = 298; 174 cases, 124 controls, ages 13-78 years (M = 28.9 SD = 11.3), 81% cisgender women]. ED diagnoses and symptoms were from an online questionnaire capturing DSM-5 diagnoses via algorithm; PTEs were assessed with the Life Events Checklist for DSM-5; and depression, anxiety, and obsessive-compulsive (OC) symptoms with validated self-report measures. Logistic regressions and analyses of covariance were adjusted for age and gender. PTEs were reported by 75% of cases and 53% of controls (adjusted odds ratio [aOR] 3.6; 95% confidence interval [CI] 2.04, 6.62), including fire/explosions (13.6; 1.30, 141.76), transportation accident (2.1; 1.13, 4.06), serious accidents (10.0; 2.03, 49.64), sexual assault (5.9; 2.57, 13.91), other uncomfortable sexual experiences (3.2; 1.68, 6.41), and other stressful event (4.3; 1.95, 9.76). Although PTEs were not significantly associated with greater depression, anxiety, or OC symptoms in cases, these co-occurring symptoms may still be relevant clinically. Results highlight the importance of assessing PTEs in Mexican individuals with EDs and encourage exploration of timing of PTE exposure to clarify their role in ED development and course.

Objective: According to DSM-5-TR, avoidant/restrictive food intake disorder (ARFID) cannot be diagnosed alongside anorexia nervosa (AN), bulimia nervosa (BN), or any other body image disturbance. This does not accurately reflect real-world symptomatology and recent research, indicating the potential need to revise DSM-5-TR Criteria. We investigated the co-occurrence of weight- and/or shape-motivated restriction (WSR) in adults who screened positive for ARFID, providing evidence to inform such changes. Methods: The sample comprised 5,747 adults who consented to participate in the ARFID-Genes and Environment (ARFID-GEN) research study, screened positive for ARFID on the NIAS and PARDI-AR-Q, and completed the EDE-Q. We placed our participants into four groups: groups one and two screened positive for AN (ARFID-AN; n=147) or BN (ARFID-BN; n=193), group three endorsed WSR without meeting AN or BN criteria (ARFID-WSR; n=2,097), and group four endorsed ARFID symptoms only (ARFID-nWSR; n=3,310). We used generalized linear models to test group differences on the NIAS, PARDI-AR-Q and EDE-Q. Results: ARFID-nWSR showed lower scores than all other groups across most ARFID dimensions on the NIAS and PARDI-AR-Q, and lower odds of meeting DSM-5-TR Criteria A1 to A4 (i.e., weight loss; nutritional deficiencies; dependence on nutritional supplements; significant interference with psychosocial functioning). Discussion: These findings indicate a mixed phenotype with features of both ARFID and WSR associated with more severe ARFID symptomatology. The DSM-5-TR Criteria may not capture complex real-world symptomatology in adults with probable ARFID, potentially precluding those with the most severe symptoms from receiving accurate diagnoses and appropriate care.

Background: The Eating Disorders Genetics Initiative 2 (EDGI2) is designed to explore the role of genes and environment in anorexia nervosa, bulimia nervosa, binge-eating disorder, and avoidant/restrictive food intake disorder (ARFID) with a focus on diverse populations and severe and/or longstanding illness.Methods: A total of 20,000 new participants (18,700 cases and 1,300 controls) will be ascertained from the United States (US), Mexico (MX), Australia (AU), Aotearoa New Zealand (NZ), Sweden (SE), and Denmark (DK). Comprehensive phenotyping and genotyping will be performed for participants in US, MX, AU, NZ, and SE using the EDGI2 questionnaire battery and participant saliva samples. In DK, case identification and genotyping will be through the National Patient Register and bloodspots archived near birth. Case-control and case-case genome-wide association studies will be conducted within EDGI2 and enhanced via meta-analysis with external data from the Eating Disorders Working Group of the Psychiatric Genomics Consortium (PGC-ED). Additional analyses will explore genetic correlations between eating disorders (EDs) and other psychiatric and metabolic traits, calculate polygenic risk scores (PRS), and leverage functional biology to evaluate clinical outcomes. Moreover, analyzing PRS for patient stratification and linking identified risk loci to clinically relevant phenotypes highlight the potential of EDGI2 for clinical translation. Discussion: EDGI2 is a global expansion of the EDGI study to increase sample size, expand the numbers of participants from non-European ancestry, and to include ARFID. Inclusion of MX will be the first large-scale ED genetics study from Latin America. ED genetics research has historically lagged behind other psychiatric disorders, and EDGI2 is designed to rapidly advance the study of the genetics of the major EDs. Exploring EDs at both the diagnostic level and the symptom level will provide an unprecedented look at the genetic architecture underlying EDs.

Objective: Although several assessments have been developed to diagnose or measure avoidant/restrictive food intake disorder (ARFID) symptoms, few studies have validated these tools in nonclinical and adult samples. This study explored the validity of two self‐ and parent/guardian‐report ARFID screening measures in identifying adults and children who may have ARFID within a large community sample.Method: Fifty participants (divided into two groups: 25 adults and 25 parents/guardians of children) were selected from the ARFID Genes and Environment study, which enrolled over 3000 adults and parents/guardians of children who screened positive for ARFID on either the Pica, ARFID, and Rumination Disorder Interview–ARFID Questionnaire (PARDI‐AR‐Q) or the Nine Item ARFID Screen (NIAS) self‐ and parent/guardian‐report measures. Participants then completed the ARFID portion of the Pica, ARFID, and Rumination Disorder Interview (PARDI) to determine ARFID diagnosis.Results: Correlations between the PARDI‐AR‐Q and PARDI (r = 0.31–0.67) were weaker than the correlations between the NIAS and PARDI (r = 0.53–0.64) in both groups. The diagnostic positive predictive value for the PARDI‐AR‐Q was numerically higher (adults = 55.0%; parents/guardians = 76.0%) than the NIAS (adults = 45.8%; parents/guardians = 64.0%). Most PARDI‐AR‐Q dimensions and all NIAS dimensions were significant predictors of their corresponding PARDI dimensions in both groups.Discussion: The PARDI‐AR‐Q more accurately identified adults and children with ARFID, whereas the NIAS was a better estimator of ARFID symptoms. These findings provide partial support for using these self‐ and parent/guardian‐report screeners. Results highlight the need to better understand diagnostic presentations of ARFID within community samples, particularly in adults, and to refine these tools within those populations.

Objective: Self‐report measures of ARFID symptoms (e.g., Nine‐Item Avoidant/Restrictive Food Intake Disorder Screen [NIAS]) are used to assess symptom differences between groups. Measurement invariance techniques clarify if groups interpret a measure similarly, providing a foundation for examining group differences. Considering age and reporter status (e.g., parent vs. self‐report), we investigated measurement invariance of the NIAS in (1) self‐reporting adults vs. adolescents; (2) parent reports on children vs. adolescents; and (3) parent reports on adolescents vs. adolescent self‐report. If measurement invariance was supported, we examined symptom differences.Methods: Data were from the ARFID Genes and Environment (ARFID‐GEN) project.Results: Self‐reporting adults vs. adolescents and parent reports of adolescents vs. adolescent self‐report interpreted the NIAS similarly (measurement invariance was supported). Measurement invariance was not supported in parent reports on children vs. adolescents. Self‐reporting adults reported higher appetite scores (i.e., lower appetite) than self‐reporting adolescents at the subscale and item level on the NIAS. Although no subscales differences were identified between parent reports on adolescents and adolescent self‐reports, parents reported more picky eating and lower appetite in adolescents than self‐reporting adolescents at the item level on the NIAS.Discussion: Findings support using the NIAS to measure symptom differences in self‐reporting adults vs. adolescents and in parent reports of adolescents vs. adolescent self‐reports. Findings may be leveraged by researchers interested in maturational effects of ARFID symptoms in adolescents and adults via self‐reports on the NIAS and clinicians interested in tracking the convergence of parent and adolescent NIAS reports while undergoing treatment for ARFID.