Eating Disorders Genetics Initiative (EDGI)

Eating Disorders Genetics Initiative (EDGI)

The overarching intention of the Eating Disorder Genetics Initiative (EDGI) is to lay the foundation for all future genomic discovery in eating disorders--anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED)--by exploring both genetic and behavioral factors. To do this, information will be collected from 4000 people who have provided DNA samples for the Anorexia Nervosa Genetics Initiative (ANGI) and the same information and DNA will be collected from an additional 16,000 people. 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: Completed
• Conditions: Anorexia Nervosa; Binge-Eating Disorder; Bulimia Nervosa
• Intervention / Treatment: Other: Eating disorder diagnosis group

• Study Type: Observational
• Enrollment (Actual): 17991

Contacts and Locations

Study Locations

• Australia
  • Queensland
    • Brisbane, Queensland, Australia
      • QIMR Berghofer
• New Zealand
  • Canterbury
    • Christchurch, Canterbury, New Zealand
      • University of Otago
• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599-7160
      • University of North Carolina

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 15 years to 99 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

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

Description

Inclusion Criteria:

• A lifetime history of anorexia nervosa, bulimia nervosa, binge-eating disorder, or no history of any disordered eating behavior
• Age 15-99 years

Exclusion Criteria:

• History of subthreshold disordered eating behaviors

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Retrospective

Number of groups / cohorts

4

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Anorexia Nervosa Case; Participants in this group have a life-time history of anorexia nervosa as determined by an algorithm applied to their responses to an eating disorders screening questionnaire (ED100K) that is based on the Structured Clinical Interview for Axis 1 Disorders.	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 Case; Participants in this group have a life-time history of bulimia nervosa as determined by an algorithm applied to their responses to an eating disorders screening questionnaire (ED100K) that is based on the Structured Clinical Interview for Axis 1 Disorders. These participants do not have a 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.
Binge-Eating Disorder Case; Participants in this group have a life-time history of binge-eating disorder as determined by an algorithm applied to their responses to an eating disorders screening questionnaire (ED100K) that is based on the Structured Clinical Interview for Axis 1 Disorders. These participants do not have a history of anorexia nervosa or 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.
Control; Participants in this group have no history of disordered eating behaviors as determined by an algorithm applied to their responses to an eating disorders screening questionnaire (ED100K) that is based on the Structured Clinical Interview for Axis 1 Disorders.	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 ED100K 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, 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 ED100K questionnaire (ED100K). Age of onset will be reported for each eating disorder group.	Baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Current eating disorder self-report total sum scores	Current eating disorder symptoms will be determined by self-report responses on the Eating Disorder Examination Questionnaire (EDEQ). Items ask about eating disorder symptoms over the past 28 days. There are four subscales of the EDEQ--Restraint, Eating Concern, Shape Concern, and Weight Concern--with scores for each ranging from 0-6. Subscales are averaged to compute a total score. Higher scores indicate more eating disorder pathology. Total and subscale sores will be reported to each eating disorder group.	Baseline
Eating disorder-related quality of life scores	Eating disorder quality of life will be 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
Health-related quality of life scores	Quality of life will be measured with the Short Form Health Survey 12 (SF-12) self-report questionnaire. The SF-12 asks 12 items assessing physical and mental health scores range from 0 to 100, with higher scores indicating better quality of life. Scores will be reported for each eating disorder group and for controls.	Baseline
Current depressive symptoms sum score	Current depressive symptoms will be measured using the Patient Health Questionnaire (PHQ). The PHQ asks 9 items about symptoms of depression over the past 2 weeks. Response options range from 0 (not at all) to 3 (nearly every day). Items are summed for a total score, ranging between 0-27 with higher scores indicating more depressive symptoms. Scores will be reported for each eating disorder group and for controls.	Baseline
Prevalence of life-time history of major depression	The prevalence of a history of major depression will be compared between eating disorder groups. Participants will complete a self-report questionnaire with items linked to the diagnostic criteria for major depression. Those individuals who indicate the presence of all the criterion required for a major depression diagnosis will be considered to have a history of major depression. Prevalence of life-time history of major depression will be reported for each eating disorder group and for controls.	Baseline
Current anxiety symptoms sum scores	Current anxiety symptoms will be measured using the Generalized Anxiety Disorder 7 (GAD7) self report questionnaire. GAD7 is a questionnaire for screening and severity measuring of generalized anxiety disorder. GAD7 consists of a total score for the seven items ranging from 0 to 21. Higher scores indicate higher levels of generalized anxiety. Scores will be reported for each eating disorder group and for controls.	Baseline
Prevalence of generalized anxiety disorder	The prevalence of a history of a generalized anxiety disorder will be compared between eating disorder groups. Participants will complete a self-report questionnaire with items linked to the diagnostic criteria for an anxiety disorder. Those individuals who indicate the presence of all the criterion required for generalized anxiety disorder diagnosis will be considered to have a history of generalized anxiety disorder. The prevalence of generalized anxiety disorder will be reported for each eating disorder group and for controls.	Baseline

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Collaborators: National Institute of Mental Health (NIMH); University of Aarhus; University of Otago; QIMR Berghofer Medical Research Institute
• Investigators: Principal Investigator: Cynthia M Bulik, PhD, University of North Carolina, Chapel Hill

Publications and helpful links

General Publications

• Bulik CM, Thornton LM, Parker R, Kennedy H, Baker JH, MacDermod C, Guintivano J, Cleland L, Miller AL, Harper L, Larsen JT, Yilmaz Z, Grove J, Sullivan PF, Petersen LV, Jordan J, Kennedy MA, Martin NG. The Eating Disorders Genetics Initiative (EDGI): study protocol. BMC Psychiatry. 2021 May 4;21(1):234. doi: 10.1186/s12888-021-03212-3.

Study record dates

Study Major Dates

• Study Start (Actual): June 12, 2020
• Primary Completion (Actual): May 31, 2023
• Study Completion (Actual): May 31, 2023

Study Registration Dates

• First Submitted: May 4, 2020
• First Submitted That Met QC Criteria: May 6, 2020
• First Posted (Actual): May 7, 2020

Study Record Updates

• Last Update Posted (Actual): June 6, 2023
• Last Update Submitted That Met QC Criteria: June 2, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Keywords: Bulimia Nervosa; Anorexia Nervosa; Binge-Eating Disorder
• Additional Relevant MeSH Terms: Mental Disorders; Pathologic Processes; Signs and Symptoms, Digestive; Hyperphagia; Anorexia; Anorexia Nervosa; Disease; Bulimia; Feeding and Eating Disorders; Binge-Eating Disorder; Bulimia Nervosa
• Other Study ID Numbers: 19-1378; R01MH120170 (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 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.
• 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

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No