The PREBA Study: Effect of Preoperative Weight Loss With a 14-day Low-calorie Diet on Surgical Procedure and Outcomes in Patients Undergoing RYGB Surgery

NCT ID: NCT04433338

Last Updated: 2025-01-03

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 80 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2020-09-29
• Study Completion Date: 2027-07-31

Brief Summary

Bariatric guidelines recommend preoperative weight loss of 5% to reduce the risk of surgical complications. However, results in the literature on the improvement of surgical procedure and outcomes are still conflicting.

This study aims to evaluate the effect of preoperative weight loss by means of a 14-day low-calorie diet in bariatric patients on operative time, the ease of the Roux-en-Y gastric bypass (RYGB) procedure and long-term weight loss in a real-life experimental setting.

Conditions

Bariatric Surgery; Morbid Obesity

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Intervention group

Participants in the intervention group will follow a low-calorie diet during 14 days before undergoing surgery. The diet will consist of both meal replacements and regular foods.

For women, the diet provides ± 900 kcal, 50 grams of carbohydrates, 85 grams of protein, 30 grams of fat and 25 grams of fibres.

For men, the diet provides ± 1000 kcal, 55 grams of carbohydrates, 100 grams of protein, 30 grams of fat and 30 grams of fibres.

Group Type: EXPERIMENTAL

14-day Low Calorie Diet

Intervention Type: OTHER

Participants will be asked to:

• Use 4 (women) or 5 (men) Modifast meal replacements per day.
• Daily consume a minimum of 250 grams of (raw) vegetables without dressing.
• Daily consume 100 grams of lean meat/fish/meat analogues.
• Daily consume two spoons of liquid oil
• Daily drink at least 2.0 litres of water, coffee or tea without added sugar or milk, bouillon or sugar-free drinks.

Control group

Participants in the control group can eat according to the standard nutritional advices provided by their dietitian. These advices are intended to educate participants on the recommended eating pattern after surgery.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

14-day Low Calorie Diet

Participants will be asked to:

• Use 4 (women) or 5 (men) Modifast meal replacements per day.
• Daily consume a minimum of 250 grams of (raw) vegetables without dressing.
• Daily consume 100 grams of lean meat/fish/meat analogues.
• Daily consume two spoons of liquid oil
• Daily drink at least 2.0 litres of water, coffee or tea without added sugar or milk, bouillon or sugar-free drinks.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Undergoing primary RYGB surgery (meeting all criteria + approval of surgeon)
• Able to prepare the meal replacements at home

Exclusion Criteria

• Undergoing another bariatric procedure than primary RYGB.
• Diabetes Mellitus
• Contraindication for the usage of Modifast meal replacements:

• Allergy or intolerance to any substance in the used meal replacements (Soy, milk, gluten, egg, peanuts, nuts and seeds)
• Veganism
• Kidney failure (GFR < 90 ml/min/1.73m2), liver failure or cardiac insufficiency
• A heart attack (myocardial infarct) in the past twelve months
• Cancer
• Hypokalaemia: serum potassium level <3.4 mmol/l
• Phenylketonuria & Porphyria

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Rijnstate Hospital

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Eric J Hazebroek, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Vitalys, part of Rijnstate hospital/Wageningen University

Locations

Rijnstate Hospital

Arnhem, Gelderland, Netherlands

Countries

Netherlands

Other Identifiers

NL70092.081.19

Identifier Type: -

Identifier Source: org_study_id