Bulimia Nervosa: A Biobehavioral Study (The Eating Disorder Study) (TEDS)

Weight Suppression, Dieting, and Bulimia Nervosa: A Biobehavioral Study

The purpose of this study is to examine biological (e.g., energy expenditure, neuroendocrine and appetitive hormones)and behavioral (e.g., binge eating and purging) correlates of weight suppression and current dieting status in women with bulimia nervosa. The investigators have differentiated between a diet-induced long-term energy imbalance (weight suppression, or the difference between one's highest-ever body weight and current weight) and a short-term energy imbalance (current dieting to either lose weight or avoid weight gain). This study will elucidate how two common yet largely unexplored types of dieting influence biological and behavioral variables in patients with bulimia nervosa, which could lead to modifications of prevailing models of bulimia nervosa and new strategies for improving treatment outcome.

Study Overview

• Status: Completed
• Conditions: Bulimia Nervosa

Detailed Description

Bulimia nervosa (BN) is a debilitating psychiatric disorder that primarily affects young women. Empirically supported treatments for BN have been identified but less than half of treated individuals achieve long-term remission from the disorder, possibly because current treatment approaches do not sufficiently account for variables that help maintain the disorder. Psychosocial models of BN emphasize the role of dieting as a proximal cause of binge eating and purging. Dieting has both psychological and biological facets but existing models of BN have overwhelmingly focused on its psychological impact. The investigators have differentiated between a diet-induced long-term energy imbalance (weight suppression (WS), or the difference between one's highest-ever body weight and current weight) and a short-term energy imbalance (current dieting to either lose weight or avoid weight gain). Recent research has shown that WS levels in BN are elevated and that degree of WS predicts the severity of various BN characteristics and its clinical course. Studies of current dieting (CD) to lose weight have found that it is associated with reduced binge eating in BN, a finding that conflicts with prevailing models of the disorder. The proposed research will examine biological (e.g., energy expenditure, neuroendocrine and appetitive hormones) and behavioral (e.g., binge eating and purging) correlates of WS and CD in those with BN. (Relatively few of those with BN report dieting to avoid weight gain but its biological and behavioral correlates will also be examined.) The project will recruit 132 women (66 at Drexel University and 66 at Columbia University) meeting provisional Diagnostic and Statistical Manual-V diagnostic criteria for BN. The investigators will test the hypotheses that 1) CD and elevated WS will be associated with alterations in biological indices of metabolism and appetite, 2) WS will predict greater binge eating and purging, and CD will predict less binge eating, measured using Ecological Momentary Assessment (EMA), and 3) higher real time ratings of daily food restriction intentions will predict a reduced probability of binge eating during the same day but an increased probability of binge eating in subsequent days. Assessments for all participants will include: weight and reported previous highest weight (to calculate WS), the Eating Disorders Examination, 14 days of EMA to assess food restriction intentions, binge eating and purging episodes, three 24-hr food recalls, and resting energy expenditure and metabolic and appetitive hormones (including complete thyroid panel, leptin, ghrelin, cortisol and estradiol). Participants will be asked to return 6 months later for follow-up assessments of weight. This study will elucidate how two common yet largely unexplored types of dieting influence biological and behavioral variables in patients with BN, which could lead to modifications of prevailing models of BN and new strategies for improving treatment outcome.

• Study Type: Observational
• Enrollment (Actual): 132

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10032
      • Columbia University
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Drexel University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from local university counseling centers and eating disorder centers.

Description

Inclusion Criteria:

• Diagnosis of bulimia nervosa according to the proposed DSM-V criteria
• Either currently receiving eating disorder treatment or actively seeking treatment
• BMI above 18.5 and below 30
• Not experiencing any signs of menopause
• Medically stable as determined by each site's study physician

Exclusion Criteria:

• Change in pharmacological treatment over past 4 weeks
• Currently taking atypical antipsychotic medications
• History of anorexia nervosa within the past year
• Pregnancy
• Currently taking medications that could alter hormone levels or metabolism
• Disorders affecting metabolism or hormone levels
• Non-removal metallic object
• Co-occurring severe mental illness
• At risk for suicide

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Women with bulimia nervosa; This is not a treatment study. All participants will go through the same steps.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Purging	Number of purging episodes recorded over two weeks.	2 week EMA period
Binge Eating	Number of binge eating episodes over two week period.	2 week EMA period
Hormone levels	Hormone levels will be assessed approximately two weeks post-baseline at one time point.	Site Visit 3 (2 weeks)
Energy intake	Energy intake (more specifically, energy density) will be assessed as an average of three dietary food recalls approximately three weeks post-baseline.	Three weeks
Resting metabolic rate (RMR)	RMR will be assessed at Site Visit 3, approximately two weeks post-baseline.	Two weeks
Total percent body fat	Total percent body fat will be assessed at Site Visit 3 (approximately 2 weeks post-baseline) using dual energy x-ray absorptiometry.	Two weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body weight	Body weight will be assessed at 6-month follow-up.	6 months
Psychosocial measures	Psychosocial self-report measures will be given at baseline.	Site Visit-Baseline

Collaborators and Investigators

• Sponsor: Drexel University
• Collaborators: Columbia University; The Miriam Hospital
• Investigators: Principal Investigator: Michael R. Lowe, Ph.D., Drexel University; Principal Investigator: Laurel Mayer, M.D., Columbia University

Study record dates

Study Major Dates

• Study Start: August 1, 2012
• Primary Completion (ACTUAL): May 31, 2018
• Study Completion (ACTUAL): May 31, 2018

Study Registration Dates

• First Submitted: March 29, 2013
• First Submitted That Met QC Criteria: April 9, 2013
• First Posted (ESTIMATE): April 12, 2013

Study Record Updates

• Last Update Posted (ACTUAL): July 30, 2018
• Last Update Submitted That Met QC Criteria: July 27, 2018
• Last Verified: July 1, 2018

More Information

Terms related to this study

• Keywords: Bulimia nervosa; Eating disorder; Dieting; Weight suppression
• Additional Relevant MeSH Terms: Mental Disorders; Signs and Symptoms, Digestive; Feeding and Eating Disorders; Hyperphagia; Bulimia; Bulimia Nervosa
• Other Study ID Numbers: 12090001548