Development of Gastrointestinal Symptoms in Patients With Anorexia Nervosa and Bulimia Nervosa During Weight Rehabilitation Over Time, Depending on the Nutritional Strategy

NCT ID: NCT07112014

Last Updated: 2025-09-23

Basic Information

• Recruitment Status: RECRUITING
• Total Enrollment: 185 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2025-09-09
• Study Completion Date: 2027-12-31

Brief Summary

This prospective observational study investigates the development of gastrointestinal (GI) symptoms in patients with anorexia nervosa (AN) and bulimia nervosa (BN) during multi-week inpatient weight rehabilitation. The study explores how the predominant nutritional strategy-flexitarian, vegetarian, or vegan-relates to changes in GI symptoms over the course of treatment. In addition to diet, the study examines how weight gain and other clinical, psychological, and demographic factors influence the trajectory of GI symptoms. Patients complete weekly questionnaires assessing GI symptoms as part of routine care at the Eating Disorder Center of the Klinik Lüneburger Heide, Germany. Further data are drawn from standard clinical assessments, including body weight, body composition, and psychometric instruments. The primary outcome is the change in GI symptom severity (measured via the GSRS score) from admission to discharge, analyzed in relation to dietary pattern and weight development. Secondary analyses will explore symptom progression over time, group differences between AN and BN, and predictors of GI symptom improvement, including dietary intake, baseline psychological status, symptom change, weight trajectory, and treatment duration. The outcomes will be analyzed separately for AN and BN. The study aims to recruit approximately 150 patients with AN and 35-40 with BN. Inclusion requires a diagnosis of AN (any subtype) or BN, age over 12 years, clinical stability, and the ability to provide informed consent. The findings aim to inform evidence-based dietary recommendations for individuals with eating disorders who experience significant GI symptoms during nutritional rehabilitation.

Detailed Description

This prospective observational study investigates the development of gastrointestinal (GI) symptoms in patients with anorexia nervosa (AN) and bulimia nervosa (BN) during multi-week inpatient weight rehabilitation. The study explores how the predominant nutritional strategy-flexitarian, vegetarian, or vegan-relates to changes in GI symptoms over the course of treatment. In addition to diet, the study examines how weight gain and other clinical, psychological, and demographic factors influence the trajectory of GI symptoms. Patients complete weekly questionnaires assessing GI symptoms as part of routine care at the Eating Disorder Center of the Klinik Lüneburger Heide, Germany. Further data are drawn from standard clinical assessments, including body weight, body composition, and psychometric instruments. The primary outcome is the change in GI symptom severity (measured via the GSRS score) from admission to discharge, analyzed in relation to dietary pattern and weight development. Secondary analyses will explore symptom progression over time, group differences between AN and BN, and predictors of GI symptom improvement, including dietary intake, baseline psychological status, symptom change, weight trajectory, and treatment duration. The study aims to recruit approximately 150 patients with AN and 35-40 with BN. Inclusion requires a diagnosis of AN (any subtype) or BN, age over 12 years, clinical stability, and the ability to provide informed consent. The findings aim to inform evidence-based dietary recommendations for individuals with eating disorders who experience significant GI symptoms during nutritional rehabilitation.

Conditions

Anorexia Nervosa; Bulimia Nervosa

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Patients with anorexia nervosa and bulimia nervosa

The study population includes patients with anorexia nervosa (AN) and bulimia nervosa (BN) who participate in an established, multi-week inpatient treatment program aimed at weight rehabilitation and normalization of eating behavior at the Eating Disorder Center of the Klinik Lüneburger Heide in 29549 Bad Bevensen, Germany. The diagnostic and treatment of the patients is as usual. These data, including detailed data on dietary intake, are used for the study. Additionally, information on gastrointestinal sympoms are assessed upon admission and discharge and weekly during the inpatient stay. The outcomes will be analyzed seperately for patients with anorexia nervosa and bulimia nervosa.

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• patients diagnosed with anorexia nervosa (all subtypes)
• patients diagnosed bulimia nervosa

Exclusion Criteria

• patients that are medically unable to fill out a short questionnaire on a weekly base.

• Minimum Eligible Age: 12 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University Hospital Tuebingen

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Isabelle Mack, Prof.

Role: PRINCIPAL_INVESTIGATOR

University Hospital Tuebingen, Internal Medicine VI, Dept. of Psychosomatic Medicine and Psychotherapy

Locations

Klinik Lüneburger Heide

Bad Bevensen, , Germany

Site Status: RECRUITING

Countries

Germany

Central Contacts

Isabelle Mack, Prof. Dr.

Role: CONTACT

i.mack@uni-tuebingen.de

+49 070712985614

Marc Leiteritz, Dr.

Role: CONTACT

m.leiteritz@klinik-lueneburger-heide.de

Facility Contacts

Marc Leiteritz, Dr.

Role: primary

m.leiteritz@klinik-lueneburger-heide.de

+49 58219600

References

Ketel J, Bosch-Bruguera M, Auchter G, Cuntz U, Zipfel S, Enck P, Mack I. Gastrointestinal Microbiota & Symptoms of Depression and Anxiety in Anorexia Nervosa-A Re-Analysis of the MICROBIAN Longitudinal Study. Nutrients. 2024 Mar 19;16(6):891. doi: 10.3390/nu16060891.

Reference Type: BACKGROUND

PMID: 38542802 (View on PubMed)

Mack I, Cuntz U, Gramer C, Niedermaier S, Pohl C, Schwiertz A, Zimmermann K, Zipfel S, Enck P, Penders J. Weight gain in anorexia nervosa does not ameliorate the faecal microbiota, branched chain fatty acid profiles, and gastrointestinal complaints. Sci Rep. 2016 May 27;6:26752. doi: 10.1038/srep26752.

Reference Type: BACKGROUND

PMID: 27229737 (View on PubMed)

Riedlinger C, Schmidt G, Weiland A, Stengel A, Giel KE, Zipfel S, Enck P, Mack I. Which Symptoms, Complaints and Complications of the Gastrointestinal Tract Occur in Patients With Eating Disorders? A Systematic Review and Quantitative Analysis. Front Psychiatry. 2020 Apr 20;11:195. doi: 10.3389/fpsyt.2020.00195. eCollection 2020.

Reference Type: BACKGROUND

PMID: 32425816 (View on PubMed)

Riedlinger C, Mazurak N, Schaffeler N, Stengel A, Giel KE, Zipfel S, Enck P, Mack I. Gastrointestinal complaints in patients with anorexia nervosa in the timecourse of inpatient treatment. Front Psychiatry. 2022 Aug 18;13:962837. doi: 10.3389/fpsyt.2022.962837. eCollection 2022.

Reference Type: BACKGROUND

PMID: 36061281 (View on PubMed)

Other Identifiers

GastroRehab

Identifier Type: -

Identifier Source: org_study_id