Eating Disorders Genetics Initiative 2 (EDGI2)

The overarching intention of the Eating Disorder Genetics Initiative 2 (EDGI2) is to increase sample size, diversity, and eating disorder phenotypes. The investigators are enrolling 20,000 new participants with anorexia nervosa (AN), bulimia nervosa (BN), binge-eating disorder (BED), avoidant/restrictive food intake disorder (ARFID), and controls in the US, Mexico, Australia, New Zealand, Sweden, and Denmark. A primary study goal is to enroll at least 30% of participants from underrepresented groups. Participants are asked to complete a series of questionnaires and submit a saliva sample for genotyping. The goal is to better understand eating disorders and how they relate to each other so that better treatments can be developed.

Study Overview

• Status: Recruiting
• Conditions: Anorexia Nervosa; Binge-Eating Disorder; Bulimia Nervosa; Avoidant Restrictive Food Intake Disorder
• Intervention / Treatment: Other: Eating disorder diagnosis group

• Study Type: Observational
• Enrollment (Estimated): 20000

Contacts and Locations

• Study Contact: Name: Laura M Thornton, PhD; Phone Number: 804-690-3079; Email: laura_thornton@med.unc.edu
• Study Contact Backup: Name: Casey MacDermod, BA; Phone Number: 984-974-3798; Email: edgi2@unc.edu

Study Locations

• Australia
  • Queensland
    • Brisbane, Queensland, Australia
      • Recruiting
      • QIMR Berghofer
      • Contact: Richard Parker; Email: richard.parker@qimeberghofer.edu.au
• Mexico
  • Monterrey, Mexico
    • Recruiting
    • Comenzar de Nuevo
    • Contact: Anid Cortes Morales; Email: anid.cortes@comenzardenuevo.net
• New Zealand
  • Canterbury
    • Christchurch, Canterbury, New Zealand
      • Recruiting
      • University of Otago
      • Contact: Jennifer Jordan; Email: jenny.jordan@otago.ac.nz
• Sweden
  • Stockholm, Sweden
    • Recruiting
    • Karolinska Institutet
    • Contact: Lisa Dinkler, PhD; Email: lisa.dinkler@ki.se
• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599-7160
      • Recruiting
      • University of North Carolina at Chapel Hill
      • Contact: Laura M Thornton, PhD; Phone Number: 804-690-3079; Email: laura_thornton@med.unc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Interested individuals from the United States, Mexico, Australia, New Zealand, and Sweden who meet criteria may participate within their respective country.

Description

Inclusion Criteria:

• A lifetime history of anorexia nervosa, bulimia nervosa, binge-eating disorder, avoidant restrictive food intake disorders or no history of any disordered eating behavior, based on DSM-5 criteria algorithms
• Age 12-99 years, depending on country. (US enrollment age is 18-99)

Exclusion Criteria:

• History of subthreshold disordered eating behaviors.

Study Plan

How is the study designed?

Number of groups / cohorts

5

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Anorexia nervosa; Individuals with a self-reported lifetime history of anorexia nervosa.	Other: Eating disorder diagnosis group; This is an observational study, no active intervention is applied. Participants are assigned to an eating disorder diagnosis group based on their lifetime history of disordered eating behaviors and symptoms.
Bulimia nervosa; Individuals with a self-reported lifetime history of bulimia nervosa.	Other: Eating disorder diagnosis group; This is an observational study, no active intervention is applied. Participants are assigned to an eating disorder diagnosis group based on their lifetime history of disordered eating behaviors and symptoms.
Binge-eating disorder; Individuals with a self-reported lifetime history of binge-eating disorder.	Other: Eating disorder diagnosis group; This is an observational study, no active intervention is applied. Participants are assigned to an eating disorder diagnosis group based on their lifetime history of disordered eating behaviors and symptoms.
ARFID; Individuals with a self-reported lifetime history of avoidant restrictive food intake disorder.	Other: Eating disorder diagnosis group; This is an observational study, no active intervention is applied. Participants are assigned to an eating disorder diagnosis group based on their lifetime history of disordered eating behaviors and symptoms.
Control; Individuals with no history of disordered eating behaviors or symptoms	Other: Eating disorder diagnosis group; This is an observational study, no active intervention is applied. Participants are assigned to an eating disorder diagnosis group based on their lifetime history of disordered eating behaviors and symptoms.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants Identified with an Eating Disorder Diagnosis by Category	The ED100Kv4 is a web-based diagnostic questionnaire, based on the Structured Clinical Interview for Axis 1 Disorders, that applies algorithms to participant responses. The number of participants with each diagnosis (AN, BN, BED, ARFID, and control) will be reported.	Baseline
Age of eating disorder onset	Age of eating disorder onset will be considered as the age of first eating disorder symptom as self-reported in the ED100Kv4 questionnaire (ED100K). Age of onset will be reported for each eating disorder group.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Current Disordered Eating Symptoms	Current eating disorder symptoms will be determined by self-report responses on the Eating Disorder Examination Questionnaire (EDEQ), the Binge Eating Disorder Screener-(BEDS7), the Nine Item ARFID Screen (NIAS), Muscle Dysmorphic Disorder Inventory (MDDI), the Drive for Muscularity Scale (DMS), and food insecurity. Items in all assessments ask about current symptoms related to eating disorders. The assessments sum scores to create subscales where higher scores indicate more eating disorder pathology and the scores taken together reveal the current disordered eating status of participants. Subscale sores will be reported for the total sample.	Baseline
Mental Health and Behavior	Current mental health symptoms (depression, anxiety, obsessive-compulsive disorder, autism, and attention-deficit/hyperactivity disorder [ADHD]) are assessed using the Patient Health Questionnaire (PHQ), Generalized Anxiety Disorder 7 (GAD7), Obsessional Compulsive Inventory - Revised (OCI-R), Autism Spectrum Quotient (AQ10), and Adult ADHD Self-Report Scale (ASRS).The assessments sum scores to create subscales where higher scores indicate more mental health symptoms and the scores taken together provide insight to current comorbidity of participants. Subscale sores will be reported for the entire sample	Baseline
Mood - Lifetime history of mood and anxiety disorders	The GLAD questionnaire asks about lifetime history of mood and anxiety symptoms. Algorithms based on Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) criteria will be applied to data to report lifetime history of mood and anxiety disorders.	Baseline
Self-Violence	A series of questions will be asked about suicidality and self-harm. The number and percent of participants indicating suicidality and self-harm will be reported.	Baseline
Lifetime Substance Use	Adapted to lifetime use, Alcohol Use Disorders Identification Test (AUDIT; 10 times) and the Drug Use Disorders Identification Test (DUDIT) are administered along with the heaviness of smoking and and questions about vaping. The AUDIT, DUDIT, and heaviness of smoking are scored using published algorithms. The prevalence of lifetime substance use will be reported for each eating disorder group.	Baseline
Life-Events	A modified version of Life Events Checklist for DSM-5 (LEC-5) is administered to collect information about 20 adverse events experienced, the age those events were first experienced, and the degree of trauma that resulted from the life events. The number and percent of each life event experienced will be reported for each eating disorder group.	Baseline
Eating Disorder Quality of Life	Eating disorder quality of life is measured with the Eating Disorder Quality of Life (EDQL) self-report questionnaire. The EDQL asks 25 items about the psychological, physical, financial, and work/school impact of an eating disorder over the past 30 days. Items are scored never (0), rarely (1), sometimes (2), often (3), or always (4). Items are summed for a total score ranging from 0-100, representing the overall impact of an eating disorder on life quality. Higher scores indicate a more significant impact of the eating disorder on life quality. Scores will be reported for each eating disorder group.	Baseline
Compulsive Exercise Test	Maladaptive exercise is evaluated using the Compulsive Exercise Test. A total of 24 questions ask about excessive or problematic exercise. Response options are on a 6-point Likert scale. There are 5 subscales, which are scored according to published criteria. Higher scores indicate greater pathology. Scores will be reported for each eating disorder group.	Baseline
Perfectionism	A shortened version (12 items) of the Multidimensional Perfectionism Scale (MPS) is used to assess 3 features of perfectionism: doubts about actions, concern over mistakes, and personal standards. Response options are on a 5-point Likert scale. Greater scores indicate higher perfectionism. Scores will be reported for each eating disorder group.	Baseline

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Collaborators: National Institute of Mental Health (NIMH); Karolinska Institutet; Yale University; University of Aarhus; University of Otago; University of Sydney; Queensland Institute of Medical Research; Comenzar de Nuevo A.C.
• Investigators: Principal Investigator: Cynthia Bulik, PhD, University of North Carolina, Chapel Hill

Study record dates

Study Major Dates

• Study Start (Actual): October 28, 2024
• Primary Completion (Estimated): August 1, 2027
• Study Completion (Estimated): August 1, 2027

Study Registration Dates

• First Submitted: September 10, 2024
• First Submitted That Met QC Criteria: September 10, 2024
• First Posted (Actual): September 19, 2024

Study Record Updates

• Last Update Posted (Actual): May 31, 2025
• Last Update Submitted That Met QC Criteria: May 30, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: genetics; mental health; environmental factors; disordered eating; severe and enduring eating disorder
• Additional Relevant MeSH Terms: Mental Disorders; Hyperphagia; Signs and Symptoms, Digestive; Avoidant Restrictive Food Intake Disorder; Bulimia; Binge-Eating Disorder; Feeding and Eating Disorders; Anorexia; Anorexia Nervosa; Bulimia Nervosa
• Other Study ID Numbers: 23-2887; R01MH136149 (U.S. NIH Grant/Contract); R01MH136157 (U.S. NIH Grant/Contract); R01MH136156 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Anonymized data and scripts will be made available to the general scientific community at the conclusion of the investigation. Specifically, phenotype data from the United States, Mexico, Australia, and New Zealand will be submitted to the database of Genotypes and Phenotypes (dbGaP) and National Institute of Mental Health Repository & Genetics Resource (NRGR) and genotype data to dbGaP. Data from Sweden will be made available on the Federated European Genome-phenome Archive.
• IPD Sharing Time Frame: Assessment phenotype data will be submitted within 6 months after the end of the study. Genotype data will be submitted after the first set of analyses with these data are complete. All data will be available as long as the repositories maintain the datasets (indefinitely).
• IPD Sharing Access Criteria: The databases are controlled-access meaning that individuals who wish to have access to the data must apply to the respective repository and meet all of their criteria.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No