Low-calorie Diet and Body Composition Prior to Roux-en-Y Gastric Bypass

Not Applicable

Completed

Brief Summary: Losing weight before undergoing Roux-en-Y gastric bypass (RYGB) surgery may reduce liver fat content and size thereby improving surgical outcomes. This study aims to investigate whether a 2-week or 6-week pre-operative liquid formula low-calorie diet (LCD) reduces liver fat further than a conventional food diet prior to RYGB using magnetic resonance imaging (MRI). The hypothesis is that the 2-week and 6-week liquid formula LCD will reduce liver fat further than the conventional food pre-operative diet.

Detailed Description: The morbidly obese subjects (BMI higher then 40 kg/m2) were randomised and assessed at baseline (week 0). After 2 weeks on a low-calorie diet (LCD), participants underwent either Roux-en-Y gastric bypass (RYGB) or continued with a LCD for 4 weeks.The participants will reassess at week 6.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Claustrophobia
Pacemaker, metal implant, clips, implanted device, shrapnel or bullets, metal in eyes that precludes magnetic resonance imaging
Current pregnancy or breast feeding for females (as determined by a pregnancy test)
A full term pregnancy within the last year for females
Treatment with any medication that might affect the study outcomes
Haemorrhagic disorders and anticoagulant treatment
History of cancer, excluding skin cancer
History of severe or multiple allergies, severe adverse drug reaction or leucopenia
Smokers
Regular drinkers of more than three units of alcohol daily
History of, or current evidence of, abuse of alcohol or any drug substance, licit or illicit
Regular intake of over-the-counter (OTC) medication (other than the occasional paracetamol/aspirin)
Poor compliers or subjects unlikely to commit to the 26 week study duration
Blood donation within the 12 week period before the initial study dose
Use of monoamine oxidase inhibitors (MAOIs) as anti depressant

Primary Outcome Measures

Name	Time	Method
Change in Intra-hepatocellular Lipid Content (IHCL) Following the Pre-operative Diet	at 2 weeks or 6 weeks depending on group	Intra-hepatocellular lipid content will be measured by magnetic resonance spectroscopy

Secondary Outcome Measures

Name	Time	Method
Operative Time	at the time of surgery	The operative time will be recorded at the time of surgery by the operating surgeon (either after 2 weeks for the Control group and 2-week LCD group or after 6 weeks for the 6-week LCD group)
Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass	at 6 months following Roux-en-Y gastric bypass	Intra-hepatocellular lipid content (IHCL) will be compared between groups at 6 months following Roux-en-Y gastric bypass
Complexity of Surgery	at the time of surgery	Complexity of surgery will be assessed by the surgeon at the time of surgery (either after 2 weeks for the Control group and 2-week LCD group or after 6 weeks for the 6-week LCD group) The complexity of the surgery was assessed through a score on a complexity scale based on questionnaires previously published by Anders Thorell"s and David Edholm"s groups (Edholm et al., 2011, Van Nieuwenhove et al., 2011). The scores (1-5) for 7 variables: exposure, bleeding, difficulty in dissection, difficulty in reconstruction, surgical judgment, technical demand and psychological stress were combined into a complexity of surgery score with a minimum of 7 (very little complexity) and a maximum of 35 (very high complexity).

Locations (1): Imperial Clinical research facility
🇬🇧
London, Greater London, United Kingdom
Imperial Clinical research facility
🇬🇧London, Greater London, United Kingdom