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

This study has been completed.
Sponsor:
Collaborator:
Fundação de Amparo à Pesquisa do Estado de São Paulo
Information provided by (Responsible Party):
Marcelo Miranda de Oliveira Lima, MD, PhD, University of Campinas, Brazil
ClinicalTrials.gov Identifier:
NCT00545805
First received: October 16, 2007
Last updated: February 17, 2013
Last verified: February 2013

October 16, 2007
February 17, 2013
October 2005
June 2009   (final data collection date for primary outcome measure)
Increase of insulin sensitivity as measured by euglycemic-hyperinsulinemic clamp. [ Time Frame: one month, six months and one year. ] [ Designated as safety issue: No ]
Increase of insulin sensitivity as measured by euglycemic-hyperinsulinemic clamp. [ Time Frame: one month, six months and one year. ]
Complete list of historical versions of study NCT00545805 on ClinicalTrials.gov Archive Site
  • 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 ]
  • increase of insulin secretion as measured by intravenous glucose tolerance test [ Time Frame: one month, six months, one year ]
  • regression of carotid intima-media thickness [ Time Frame: one month, six months, one year ]
  • Improvement of the insulin cell signalling in the subcutaneous adipose tissue. [ Time Frame: one month, six months ]
  • increase of adipocytokines linked to greater insulin sensitivity and decrease of others linked to insulin resistance [ Time Frame: one month, six months, one year ]
Not Provided
Not Provided
 
Surgical Removal of Visceral Fat Tissue (Omentectomy) Associated to Bariatric Surgery: Effects on Insulin Sensitivity
Effects of the Surgical Removal of Visceral Fat Tissue (Omentectomy) on Insulin Sensitivity in Grade III Obese Volunteers Subjected to Bariatric Surgery

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.

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).

Interventional
Phase 2
Phase 3
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
  • Insulin Resistance
  • Obesity
  • Metabolic Syndrome X
  • Procedure: Roux-en-Y Gastric Bypass plus total omentectomy
    Roux-en-Y Gastric Bypass plus total omentectomy
  • Procedure: Roux-en-Y Gastric Bypass
    Roux-en-Y Gastric Bypass without omentectomy
  • Experimental: OM group
    Intervention: Procedure: Roux-en-Y Gastric Bypass plus total omentectomy
  • Active Comparator: CT group
    Control group
    Intervention: Procedure: Roux-en-Y Gastric Bypass

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
20
June 2009
June 2009   (final data collection date for primary outcome measure)

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.
Female
18 Years to 50 Years
No
Contact information is only displayed when the study is recruiting subjects
Brazil
 
NCT00545805
LIMED0001, FAPESP 05/58627-2
No
Marcelo Miranda de Oliveira Lima, MD, PhD, University of Campinas, Brazil
University of Campinas, Brazil
Fundação de Amparo à Pesquisa do Estado de São Paulo
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)
University of Campinas, Brazil
February 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP