Morbid Obesity, Liver Fat
Conditions
Keywords
morbid obesity, gastric bypass, bariatrics, diet, caloric restriction, liver fat, appetite
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.
Interventions
DIETARY_SUPPLEMENTLiquid formula low-calorie diet (LCD)
The liquid formula low-calorie diet (LCD) will provide 800kcal/day from powdered milkshakes and soups. The diet will be provided by Cambridge Weight Plan.
PROCEDURERoux-en-Y gastric bypass (RYGB)
Participant went through Roux-en-Y gastric bypass (RYGB) surgery
OTHERControl diet
Sponsors
Cambridge Weight Plan Limited
Imperial College London
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* patients undergoing Roux-en-Y gastric bypass at Imperial Weight Centre * aged 18 to 60 years * boby mass index of 35 to 55 kg/m2
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | at 1-month following Roux-en-Y gastric bypass | Intra-hepatocellular lipid content (IHCL) will be compared between groups at 1 month 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 Thorells and David Edholms 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). |
| 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) |
Countries
United Kingdom
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) A 2-week liquid formula low-calorie diet (LCD) will be administered for 2 weeks prior to Roux-en-Y gastric bypass. The diet will provide 800kcal per day in the form of powdered milkshakes and soups
Liquid formula low-calorie diet (LCD): The liquid formula low-calorie diet (LCD) will provide 800kcal/day from powdered milkshakes and soups. The diet will be provided by Cambridge Weight Plan.
Roux-en-Y gastric bypass (RYGB): Participant went through Roux-en-Y gastric bypass (RYGB) surgery | 9 |
| 6-week LCD A 6-week liquid formula low-calorie diet (LCD) will be administered for 6 weeks prior to Roux-en-Y gastric bypass. The diet will provide 800kcal per day in the form of powdered milkshakes and soups
Liquid formula low-calorie diet (LCD): The liquid formula low-calorie diet (LCD) will provide 800kcal/day from powdered milkshakes and soups. The diet will be provided by Cambridge Weight Plan. | 8 |
| Control Diet 1000 calorie diet
Roux-en-Y gastric bypass (RYGB): Participant went through Roux-en-Y gastric bypass (RYGB) surgery
Control diet | 7 |
| Total | 24 |
Baseline characteristics
| Characteristic | 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | 6-week LCD | Control Diet | Total |
|---|---|---|---|---|
| Age, Continuous | 40 years | 46 years | 40 years | 42 years |
| Sex: Female, Male Female | 8 Participants | 6 Participants | 5 Participants | 19 Participants |
| Sex: Female, Male Male | 1 Participants | 2 Participants | 2 Participants | 5 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 10 | 0 / 9 | 0 / 10 |
| other Total, other adverse events | 0 / 10 | 0 / 9 | 0 / 10 |
| serious Total, serious adverse events | 0 / 10 | 0 / 9 | 0 / 10 |
Outcome results
Primary
Change in Intra-hepatocellular Lipid Content (IHCL) Following the Pre-operative Diet
Intra-hepatocellular lipid content will be measured by magnetic resonance spectroscopy
Time frame: at 2 weeks or 6 weeks depending on group
Population: The numbers are not the same because depending on the variable measured (some might have missing data) and its timepoint (baseline, visit 2, 3 or 4), there are more or less patients. For example, 29 were initially enrolled, 24 had data available after the baseline visit, 21 had MRI liver data at visit 3 (1 motnh post surgery) and 16 had MRI liver data at 6 months.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | Change in Intra-hepatocellular Lipid Content (IHCL) Following the Pre-operative Diet | 40.0 percentage of change in IHCL | Standard Error 7.1 |
| 6-week LCD | Change in Intra-hepatocellular Lipid Content (IHCL) Following the Pre-operative Diet | 67.4 percentage of change in IHCL | Standard Error 9.1 |
| Control Diet | Change in Intra-hepatocellular Lipid Content (IHCL) Following the Pre-operative Diet | 0.1 percentage of change in IHCL | Standard Error 8.3 |
Secondary
Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass
Intra-hepatocellular lipid content (IHCL) will be compared between groups at 1 month following Roux-en-Y gastric bypass
Time frame: at 1-month following Roux-en-Y gastric bypass
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 31.8 percentage change in IHCL | Standard Error 13.4 |
| 6-week LCD | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 57.8 percentage change in IHCL | Standard Error 11.9 |
| Control Diet | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 26.4 percentage change in IHCL | Standard Error 15.1 |
Secondary
Change in Intra-hepatocellular Lipid Content (IHCL) 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
Time frame: at 6 months following Roux-en-Y gastric bypass
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 69.8 percentage change in IHCL | Standard Error 16.5 |
| 6-week LCD | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 88.1 percentage change in IHCL | Standard Error 3.5 |
| Control Diet | Change in Intra-hepatocellular Lipid Content (IHCL) Following Roux-en-Y Gastric Bypass | 83.0 percentage change in IHCL | Standard Error 8.3 |
Secondary
Complexity 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 Thorells and David Edholms 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).
Time frame: at the time of surgery
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | Complexity of Surgery | 12 scores on a scale | Standard Error 5 |
| 6-week LCD | Complexity of Surgery | 13 scores on a scale | Standard Error 3 |
| Control Diet | Complexity of Surgery | 12 scores on a scale | Standard Error 4 |
Secondary
Operative Time
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)
Time frame: at the time of surgery
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 2-week LCD and Roux-en-Y Gastric Bypass (RYGB) | Operative Time | 86 minutes | Standard Deviation 13 |
| 6-week LCD | Operative Time | 72 minutes | Standard Deviation 8 |
| Control Diet | Operative Time | 72 minutes | Standard Deviation 6 |