Surgical Removal of Visceral Fat Tissue (Omentectomy) Associated to Bariatric Surgery: Effects on Insulin Sensitivity - Full Text View

Sponsors and Collaborators:	University of Campinas, Brazil Fundação de Amparo à Pesquisa do Estado de São Paulo
Information provided by:	University of Campinas, Brazil
ClinicalTrials.gov Identifier:	NCT00545805

Purpose

The intraabdominal fat is associated with insulin resistance, a condition that is in the basis of diabetes, metabolic syndrome and some cardiovascular diseases. It is not clear whether it is the origin of it or a surrogate marker only. We intend to compare the effects of bariatric surgery with versus without omentectomy in morbidly obese people intended to go through bariatric surgery, accessing insulin sensitivity by metabolic tests.

If the visceral fat is causative of insulin resistance, its surgical removal (omentectomy) might lead to improvement of insulin action, as seen in animal studies and in one study with morbidly obese human volunteers.

Condition	Intervention	Phase
Insulin Resistance Obesity Metabolic Syndrome X	Procedure: Roux-en-Y Gastric Bypass plus total omentectomy Procedure: Roux-en-Y Gastric Bypass	Phase II Phase III

MedlinePlus related topics: Metabolic Syndrome Obesity Surgery Weight Loss Surgery

Drug Information available for: Insulin

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Open Label, Parallel Assignment, Efficacy Study
Official Title:	Effects of the Surgical Removal of Visceral Fat Tissue (Omentectomy) on Insulin Sensitivity in Grade III Obese Volunteers Subjected to Bariatric Surgery

Further study details as provided by University of Campinas, Brazil:

Primary Outcome Measures:

Increase of insulin sensitivity as measured by euglycemic-hyperinsulinemic clamp. [ Time Frame: one month, six months and one year. ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

increase of insulin secretion as measured by intravenous glucose tolerance test [ Time Frame: one month, six months, one year ] [ Designated as safety issue: No ]
regression of carotid intima-media thickness [ Time Frame: one month, six months, one year ] [ Designated as safety issue: No ]
Improvement of the insulin cell signalling in the subcutaneous adipose tissue. [ Time Frame: one month, six months ] [ Designated as safety issue: No ]
increase of adipocytokines linked to greater insulin sensitivity and decrease of others linked to insulin resistance [ Time Frame: one month, six months, one year ] [ Designated as safety issue: No ]

Estimated Enrollment:	24
Study Start Date:	October 2005
Estimated Study Completion Date:	February 2009
Estimated Primary Completion Date:	February 2009 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Experimental	Procedure: Roux-en-Y Gastric Bypass plus total omentectomy Roux-en-Y Gastric Bypass plus total omentectomy
2: Active Comparator	Procedure: Roux-en-Y Gastric Bypass Roux-en-Y Gastric Bypass without omentectomy

Detailed Description:

In order to verify a potential additional benefit of omentectomy combined to Roux-en-Y silastic ring gastric bypass, insulin sensitivity will be studied by the gold-standard test, euglycemic-hyperinsulinemic clamp, since early postoperative follow-up (before significant weight variation), compared to a control group of bariatric surgery (same technique) alone. The variables will be analyzed in the post surgical evolution for correlation to metabolic changes: adiposity-related hormones and cytokines; lipid profile and other cardiovascular risk factors; molecular expression of biopsied subcutaneous adipocytes in vitro; anthropometrics; ultrasonography of abdominal subcutaneous and intra-abdominal fat depots and carotid intima-media thickness (preclinical atherosclerosis evaluation).

Eligibility

Ages Eligible for Study:	18 Years to 50 Years
Genders Eligible for Study:	Female
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Age between 21 and 50 years.
Female sex.
BMI between 40 and 50kg/m2.
Metabolic syndrome (NCEP/ATP III criteria).

Exclusion Criteria:

Weight variation >5% within 3 months prior to preoperative tests.
Use of antidiabetic medications within 3 months prior to preoperative tests.
HbA1c >8%.
Use of systemic corticosteroids for longer than 1 week within 3 months prior to preoperative tests.
Hepatic cirrhosis, renal failure or any clinical condition (other than obesity) recognized as impairing insulin sensitivity.
Present Smoking.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00545805

Locations

Brazil, SP
LIMED (Laboratory of Investigation of Metabolism and Diabetes)/GASTROCENTRO/Univeristy of Campinas (UNICAMP)
Campinas, SP, Brazil

Sponsors and Collaborators

University of Campinas, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo

Investigators

Principal Investigator:	Marcelo MO Lima, MD	University of Campinas (UNICAMP)
Principal Investigator:	Bruno Geloneze, PhD	University of Campinas (UNICAMP)
Principal Investigator:	José Carlos Pareja, PhD	University of Campinas (UNICAMP)

More Information

Publications:

Thorne A, Lonnqvist F, Apelman J, Hellers G, Arner P. A pilot study of long-term effects of a novel obesity treatment: omentectomy in connection with adjustable gastric banding. Int J Obes Relat Metab Disord. 2002 Feb;26(2):193-9.

Barzilai N, She L, Liu BQ, Vuguin P, Cohen P, Wang J, Rossetti L. Surgical removal of visceral fat reverses hepatic insulin resistance. Diabetes. 1999 Jan;48(1):94-8.

Gabriely I, Ma XH, Yang XM, Atzmon G, Rajala MW, Berg AH, Scherer P, Rossetti L, Barzilai N. Removal of visceral fat prevents insulin resistance and glucose intolerance of aging: an adipokine-mediated process? Diabetes. 2002 Oct;51(10):2951-8.

Pitombo C, Araujo EP, De Souza CT, Pareja JC, Geloneze B, Velloso LA. Amelioration of diet-induced diabetes mellitus by removal of visceral fat. J Endocrinol. 2006 Dec;191(3):699-706.

Responsible Party:	University of Campinas, Brazil ( Marcelo Miranda de Oliveira Lima )
Study ID Numbers:	LIMED0001, FAPESP 05/58627-2
Study First Received:	October 16, 2007
Last Updated:	February 2, 2009
ClinicalTrials.gov Identifier:	NCT00545805 History of Changes
Health Authority:	Brazil: National Committee of Ethics in Research

Keywords provided by University of Campinas, Brazil:

Insulin resistance
Metabolic syndrome X
Obesity
Intra-Abdominal Fat
Omentum

Bariatric surgery
Glucose Clamp Technique
Intravenous Glucose Tolerance Test
Adiponectin
Cytokines

Study placed in the following topic categories:

Obesity
Metabolic Syndrome X
Metabolic Diseases
Overweight
Insulin
Abdominal Obesity Metabolic Syndrome
Body Weight

Hyperinsulinism
Signs and Symptoms
Nutrition Disorders
Overnutrition
Insulin Resistance
Glucose Metabolism Disorders
Metabolic Disorder

Additional relevant MeSH terms:

Obesity
Metabolic Syndrome X
Metabolic Diseases
Disease
Overweight
Body Weight
Hyperinsulinism

Signs and Symptoms
Pathologic Processes
Syndrome
Nutrition Disorders
Overnutrition
Insulin Resistance
Glucose Metabolism Disorders

ClinicalTrials.gov processed this record on May 06, 2009