Digestion and gut function after bariatric surgery

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Adults aged 18–65 with obesity (BMI >30) or at least one year after Roux‑en‑Y or sleeve gastrectomy will be enrolled. In the first visit, researchers will collect aspirates from multiple regions of the gastrointestinal tract via a naso‑intestinal catheter to measure gastric and pancreatic enzyme activity and bile acid concentrations. In a second visit participants will swallow an ingestible telemetric capsule that continuously records pH and other physiological parameters along the entire gut to determine transit times. The observational protocol aims to compare regional digestion and physiology after bariatric surgery with findings in people living with obesity.

Why it matters

Who can join: the full rules

Inclusion Criteria:

Participants eligible for inclusion in this Investigation have to meet all of the following criteria:

1. Voluntary written informed consent of the participant has been obtained prior to any screening procedures
2. Age: 18-65 years

   Specific inclusion criteria for the different patient populations:

   Patients with obesity:
3. Body Mass Index: \> 30 kg/m2

   Patients after bariatric surgery:
4. Surgery: at least one year after Roux-en-Y gastric bypass or sleeve gastrectomy

Exclusion Criteria:

Participants eligible for this Investigation must not meet any of the following criteria:

1. Patient has history of more than one bariatric surgery
2. Patient has a waist circumference \> 125.6 cm
3. Patient had gastrointestinal surgery in the past three months
4. Patient has a pacemaker, defibrillator, infusion pump, or other portable or implanted electromedical device
5. Patient had frequent exposure to X-rays in the past year
6. Patient has swallowing disorders, among others: dysphagia for food or pills, any oropharyngeal or oesophageal stricture, anxiety or functional abnormality
7. Patient has Crohn's disease or Diverticulitis
8. Patient has gastrointestinal strictures, fistulas or physiological/mechanical obstructions
9. Patient has gastric bezoar
10. Patient has a history of complex bowel resection or known abdominal adhesions
11. Patient has short bowel syndrome or ostomy
12. Patient has currently ongoing infections
13. Patient is planned to undergo usage of rectal foam/enema or treatment with adjuvant chemotherapy or radiotherapy
14. Patient is currently on parenteral diet
15. Patient is planned to undergo MRI procedure during usage of the wireless capsule
16. Patient is working in a professional healthcare facility (e.g. hospital, dental office, emergency room), military area (e.g. submarine, near radar installation), or heavy industrial area (e.g. power plants, automotive, mining, refineries) during the duration of the clinical investigation
17. Patient is pregnant, breastfeeding, actively trying to get pregnant or had recent childbirth in last 6 months
18. Patient cannot discontinue medication that affects gastrointestinal transit time and/or pH for at least 3 days before and during the study (and 4 weeks for weekly/long-acting GLP-1 analogues such as Saxenda, Ozempic, Wegovy, Mounjaro). This includes opioids (e.g., morphine, codeine), proton pump inhibitors (e.g., omeprazole, esomeprazole, pantoprazole), H2-receptor antagonists (e.g., cimetidine, famotidine), antacids, sucralfate, prokinetics (e.g., domperidone, metoclopramide), antidiarrheal agents (e.g., loperamide), antibiotics, probiotics and prebiotics.
19. Any disorder, which in the investigator's opinion might jeopardise participant's safety or compliance with the CIP.

Where it's running

• Universitaire Ziekenhuizen KU Leuven
  Leuven, Netherlands Recruiting

Study contacts

• Study coordinator: Maaike De Kreek, MSc
• Email: maaike.dekreek@kuleuven.be
• Phone: +32 16 34 72 89

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• 15-year outcomes after sleeve gastrectomy in France

  This study looks at how people who had sleeve gastrectomy have fared over 15 years to see long-term weight changes and health effects.

  Recruiting Centre Hospitalier Universitaire, Amiens · Amiens · NCT07883018

• Collagen Supplements After Sleeve Gastrectomy

  This observational study looks to see if taking collagen-containing supplements after sleeve gastrectomy affects muscle mass, body composition, and body image in adults who had bariatric surgery.

  Recruiting Mudanya University · Bursa, Yıldırım · NCT07809152

• Dramatherapy Added to Physical Activity for Obesity Care

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  Recruiting Universite du Littoral Cote d'Opale · Blendecques, Hauts-de-France · NCT07685483

• Time-restricted eating after bariatric surgery

  This study tests whether a 16:8 eating window helps adults with obesity, including those who have had bariatric surgery, see weight or metabolic improvements.

  Recruiting at 2 sites Medipol University · Bursa, Lütfen Seçiniz. and 1 other locations · NCT07672821

• Scalp hair chemical changes in people with severe obesity and after bariatric surgery

  This project will see if chemicals trapped in scalp hair change with body weight and can signal hair thinning or muscle loss in adults having bariatric surgery.

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• A new surgical approach to reduce GERD after weight loss surgery

  This study is testing a new type of weight loss surgery to see if it can help reduce acid reflux in people who have had weight loss surgery.

  Recruiting at 2 sites University of California, Irvine · Orange, California and 1 other locations · NCT06783751

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.