Effect of Gastric Bypass Surgery on Energy Metabolism - Full Text View

Purpose

The purpose of this study is to investigate the short term and long term effects of Roux-en-Y gastric bypass (RYGB) surgery on energy expenditure, gastrointestinal and appetite regulating hormone levels, and appetite sensation. We hypothesize that following RYGB surgery, metabolism will be elevated in comparison to patients who have not yet had RYGB but who are losing weight simultaneously using a low calorie diet. We further hypothesize that this higher metabolism will be associated with alterations in fasting and postmeal levels of gastrointestinal and appetite regulating hormones. Long term (2 years after RYGB), we hypothesize that differences in metabolism, body composition, and hormone levels will distinguish between patients who have maintained their weight loss after RYGB vs those who have regained weight.

Condition	Intervention
Obesity	Procedure: Roux-en-Y gastric bypass surgery Dietary Supplement: low calorie diet (1,000 kcal/day)

Study Type:	Interventional
Study Design:	Allocation: Randomized Intervention Model: Parallel Assignment Masking: Open Label Primary Purpose: Diagnostic
Official Title:	ERGEM: Effect of Roux-en-Y Gastric Bypass Surgery on Energy Metabolism.

Resource links provided by NLM:

MedlinePlus related topics: Obesity

U.S. FDA Resources

Further study details as provided by University of Copenhagen:

Primary Outcome Measures:

Change in 24 hour energy expenditure [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

change in fasting bile acids and lipid profile [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]
changes in fasting levels of leptin, adiponectin, and visfatin [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]
change in body composition [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]
Change in appetite sensation [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]
change in fasting and postprandial levels of GLP-1, PYY, oxyntomodulin, glucose, insulin, C peptide, GIP, ghrelin, cholecystokinin [ Time Frame: 7 weeks, 10 weeks (short term); 2 years (long term) ] [ Designated as safety issue: No ]

Estimated Enrollment:	48
Study Start Date:	September 2009
Estimated Study Completion Date:	April 2013
Estimated Primary Completion Date:	April 2013 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: Earlier gastric bypass surgery (7 weeks) These patients will undergo gastric bypass surgery 7 weeks after starting a low calorie diet, and will continue the low calorie diet for 3 weeks following surgery.	Procedure: Roux-en-Y gastric bypass surgery Briefly, RYGB is characterized first by creation of a small stomach pouch. The small intestine is then divided approximately 75 cm distal to the ligament of Treitz, creating a proximal intestinal limb that transports the secretions from the stomach remnant, liver, and pancreas, and a 'Roux' limb, that is attached to the new stomach pouch to drain consumed food. The distal end of the proximal limb is then reattached approximately 100 cm distal to the new stomach drainage site, creating a common channel where digestive enzymes mix with ingested food. Dietary Supplement: low calorie diet (1,000 kcal/day) Patients will consume a daily diet composed of: 4 powder diet portions (Cambridge Diets, UK) plain yogurt (100-125g) skim milk (1L) a limited variety of vegetables The diet will be consumed by both groups for a 10 week period. Other Name: Cambridge Weight Plan, Northants, UK.
Active Comparator: Later gastric bypass surgery (10 weeks) These patients will undergo gastric bypass surgery 10 weeks after starting a low calorie diet.	Procedure: Roux-en-Y gastric bypass surgery Briefly, RYGB is characterized first by creation of a small stomach pouch. The small intestine is then divided approximately 75 cm distal to the ligament of Treitz, creating a proximal intestinal limb that transports the secretions from the stomach remnant, liver, and pancreas, and a 'Roux' limb, that is attached to the new stomach pouch to drain consumed food. The distal end of the proximal limb is then reattached approximately 100 cm distal to the new stomach drainage site, creating a common channel where digestive enzymes mix with ingested food. Dietary Supplement: low calorie diet (1,000 kcal/day) Patients will consume a daily diet composed of: 4 powder diet portions (Cambridge Diets, UK) plain yogurt (100-125g) skim milk (1L) a limited variety of vegetables The diet will be consumed by both groups for a 10 week period. Other Name: Cambridge Weight Plan, Northants, UK.

Arms

Assigned Interventions

Experimental: Earlier gastric bypass surgery (7 weeks)

These patients will undergo gastric bypass surgery 7 weeks after starting a low calorie diet, and will continue the low calorie diet for 3 weeks following surgery.

Procedure: Roux-en-Y gastric bypass surgery

Briefly, RYGB is characterized first by creation of a small stomach pouch. The small intestine is then divided approximately 75 cm distal to the ligament of Treitz, creating a proximal intestinal limb that transports the secretions from the stomach remnant, liver, and pancreas, and a 'Roux' limb, that is attached to the new stomach pouch to drain consumed food. The distal end of the proximal limb is then reattached approximately 100 cm distal to the new stomach drainage site, creating a common channel where digestive enzymes mix with ingested food.

Dietary Supplement: low calorie diet (1,000 kcal/day)

Patients will consume a daily diet composed of:

4 powder diet portions (Cambridge Diets, UK)
plain yogurt (100-125g)
skim milk (1L)
a limited variety of vegetables

The diet will be consumed by both groups for a 10 week period.

Other Name: Cambridge Weight Plan, Northants, UK.

Active Comparator: Later gastric bypass surgery (10 weeks)

These patients will undergo gastric bypass surgery 10 weeks after starting a low calorie diet.

Procedure: Roux-en-Y gastric bypass surgery

Briefly, RYGB is characterized first by creation of a small stomach pouch. The small intestine is then divided approximately 75 cm distal to the ligament of Treitz, creating a proximal intestinal limb that transports the secretions from the stomach remnant, liver, and pancreas, and a 'Roux' limb, that is attached to the new stomach pouch to drain consumed food. The distal end of the proximal limb is then reattached approximately 100 cm distal to the new stomach drainage site, creating a common channel where digestive enzymes mix with ingested food.

Dietary Supplement: low calorie diet (1,000 kcal/day)

Patients will consume a daily diet composed of:

4 powder diet portions (Cambridge Diets, UK)
plain yogurt (100-125g)
skim milk (1L)
a limited variety of vegetables

The diet will be consumed by both groups for a 10 week period.

Other Name: Cambridge Weight Plan, Northants, UK.

Eligibility

Ages Eligible for Study:	18 Years to 65 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Age 18-65
BMI ≥40, or ≥35 with concomitant obstructive sleep apnea, or hypertension
scheduled for RYGB surgery at Hvidovre Hospital, Copenhagen, Denmark
Must have lost between 1-4% body weight after 3 months of dietary counselling

Exclusion Criteria:

Deemed ineligible for RYGB surgery by patient's own physician(s)
Diabetes Mellitus
Non Caucasian
Weight >160kg (due to DEXA scanner limitations), or morphologically unable to accommodate in DEXA scanner (>40cm in maximum supine anterior-posterior dimension, or >60cm in maximum supine body width)
Hemoglobin <7.0 mmol/L
Psychiatric illness under the care of a psychiatrist
Eating disorder such as bulimia
Patients on special diets (eg vegetarian, Atkins)
Any history of thyroid dysfunction, or use of thyroid medication (with the exception of transient thyroiditis)
Hypothalamic or genetic etiology of obesity
A current diagnosis of cancer
Any surgery other than RYGB planned in the ensuing 3 months
Substance abuse or smoking
Use of prescription medications or over-the-counter drugs affecting metabolism
Excessive intake of alcohol (>7 drinks/week)
Excessive intake of caffeine (>300 mg/day)
Presence of any contraindication to use of a low calorie powder diet, including:
- Past history of ventricular arrhythmias (even if treated)
- Renal dysfunction (creatinine clearance <60 mL/min)
- Liver enzymes (ALT or AST) >3x upper limit of normal
- Milk protein allergy, or lactose intolerance
- Porphyria or phenylketonuria
- History of gout
- Breastfeeding
- Concomitant use of monoamine oxidase inhibitors or non potassium sparing diuretics
- Inability or unwillingness to comply with a low calorie diet protocol
- Patients who find the powder diet products to be unpalatable
Do not enjoy yogurt, carrots, or milk (as these are essential elements of the low calorie diet)

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00939679

Locations

Denmark
Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen
Copenhagen, Denmark, 1958
Hvidovre Hospital
Copenhagen, Denmark, 2650

Sponsors and Collaborators

University of Copenhagen

Cambridge Weight Plan, Northants, UK

Investigators

Principal Investigator:

Nikolaj T Gregersen, MSc

University of Copenhagen

More Information

No publications provided

Responsible Party:	AAstrup, Head of Department, University of Copenhagen
ClinicalTrials.gov Identifier:	NCT00939679 History of Changes
Other Study ID Numbers:	B263
Study First Received:	July 14, 2009
Last Updated:	June 14, 2012
Health Authority:	Denmark: Danish Data Protection Agency Denmark: Danish National Committee on Biomedical Research Ethics

Keywords provided by University of Copenhagen:

obesity
bariatric surgery
energy expenditure
incretins

appetite regulation
body composition
GLP-1

Additional relevant MeSH terms:

Obesity
Overnutrition
Nutrition Disorders

Overweight
Body Weight
Signs and Symptoms

ClinicalTrials.gov processed this record on May 16, 2013

Effect of Gastric Bypass Surgery on Energy Metabolism (ERGEM)