NCT07565051Recruiting
Can Pre-operative Lean Mass Predict Weight Loss After Roux-en-Y Gastric Bypass?
Source: ClinicalTrials.gov · Last updated 8 May 2026
Brief summary (registry, in English)
The goal of this observational study is to evaluate whether preoperative fat-free mass predicts post-operative weight loss in patients undergoing Roux-En-Y gastric bypass. The primary objective of this study is to evaluate whether preoperative fat-free mass predicts weight loss in the two years following RYGB. The investigators will collect the following data, assessed as part of routine follow-up: * height, weight, hip and waist circumferences * body composition by bioimpedance analysis and dual energy-X-ray absorptiometry * Muscle strength and physical activity * Nutritional parameters: resting energy expenditure, eating behavior and digestive tolerance", plasma micronutrient status. . * Cardiovascular risk factors: fasting glucose, blood levels of Hb1Ac, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, blood pressure * Co-morbidities: joint pain and arthritis, sleep apnea, gastro-oesophageal reflux, metabolic dysfunction-associated fatty liver disease (MAFLD), cancer, stroke, heart attack. Quality of life: quality of life by the "Bariatric Analysis and Reporting Outcome (BAROS) questionnaire", symptoms of dumping syndrome by the "Sigstad diagnostic score system" Birthdate, birthweight and term of their children
- Status (registry)
- Recruiting
- Study type
- Observational
- Enrollment
- 91 (estimated)
- First submitted
- 27 Apr 2026
- Start date
- Aug 2025
- Primary completion date
- Aug 2027
- Lead sponsor
- University Hospital, Geneva
- Diseases
- Obesity
- NCT number
- NCT07565051
What you commit to
- Study type: Observational
- Planned participants: 91
- From Aug 2025 to the primary completion date, Aug 2027
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Planification for another type of bariatric surgery than RYGB
Lab values
- Contra-indications to bariatric surgery as stated under www.smob.ch: insufficient nutritional knowledge in nutrition to lose weight, pregnancy, kidney failure (Creatinine ≥ 300 umol/l without dialysis, Crohn's disease, active cancer or remission \< 2 years, active psychiatric disease, substance abuse (alcohol, cannabis, opioids), absence of compliance, lack of understanding of the requirements and necessary lifestyle changes reported by physician or dietician.
Other
- Inability or refusal to give consent.
Who the study is looking for
- Patients ≥ 18 years AND
- Meeting inclusion criteria for RYGB (www.smob.ch): BMI ≥35 kg/m2, failure of weight-reducing programs over 2 years (for patients with a BMI ≥50 kg/m2, 1 year), understanding of the necessity to change the lifestyle and eating habits post-operatively, signed consent for lifelong post-operative follow-up in a recognized bariatric center AND
- Scheduled RYGB at the HUG OR previous RYGB at the HUG with a present follow-up in Clinical Nutrition and dietetics at the HUG AND
- Understanding French
Sex: All · Does not accept healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Geneva University Hospitals Coordinator of this site? Confirm its status | Geneva | Switzerland | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.