TY - JOUR

T1 - Surgical removal of omental fat does not improve insulin sensitivity and cardiovascular risk factors in obese adults

AU - Fabbrini, Elisa

AU - Tamboli, Robyn A

AU - Magkos, Faidon

AU - Marks-Shulman, Pamela A

AU - Eckhauser, Aaron W

AU - Richards, William O

AU - Klein, Samuel

AU - Abumrad, Naji N

N1 - Copyright (c) 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

PY - 2010

Y1 - 2010

N2 - Background & aims: Visceral adipose tissue (VAT) is an important risk factor for the metabolic complications associated with obesity. Therefore, a reduction in VAT is considered an important target of obesity therapy. We evaluated whether reducing VAT mass by surgical removal of the omentum improves insulin sensitivity and metabolic function in obese patients.Methods: We conducted a 12-month randomized controlled trial to determine whether reducing VAT by omentectomy in 22 obese subjects increased their improvement following Roux-en-Y gastric bypass (RYGB) surgery in hepatic and skeletal muscle sensitivity to insulin study 1. Improvement was assessed by using the hyperinsulinemic-euglycemic clamp technique. We also performed a 3-month, longitudinal, single-arm study to determine whether laparoscopic omentectomy alone, in 7 obese subjects with type 2 diabetes mellitus (T2DM), improved insulin sensitivity study 2. Improvement was assessed by using the Frequently Sampled Intravenous Glucose Tolerance Test.Results: The greater omentum, which weighed 0.82 kg (95% confidence interval: 0.67-0.97), was removed from subjects who had omentectomy in both studies. In study 1, there was an approximate 2-fold increase in muscle insulin sensitivity (relative increase in glucose disposal during insulin infusion) and a 4-fold increase in hepatic insulin sensitivity 12 months after RYGB alone and RYGB plus omentectomy, compared with baseline values (P<.001). There were no significant differences between groups (P>.87) or group x time interactions (P>.36). In study 2, surgery had no effect on insulin sensitivity (P=.844) or use of diabetes medications.Conclusions: These results demonstrate that decreasing VAT through omentectomy, alone or in combination with RYGB surgery, does not improve metabolic function in obese patients.

AB - Background & aims: Visceral adipose tissue (VAT) is an important risk factor for the metabolic complications associated with obesity. Therefore, a reduction in VAT is considered an important target of obesity therapy. We evaluated whether reducing VAT mass by surgical removal of the omentum improves insulin sensitivity and metabolic function in obese patients.Methods: We conducted a 12-month randomized controlled trial to determine whether reducing VAT by omentectomy in 22 obese subjects increased their improvement following Roux-en-Y gastric bypass (RYGB) surgery in hepatic and skeletal muscle sensitivity to insulin study 1. Improvement was assessed by using the hyperinsulinemic-euglycemic clamp technique. We also performed a 3-month, longitudinal, single-arm study to determine whether laparoscopic omentectomy alone, in 7 obese subjects with type 2 diabetes mellitus (T2DM), improved insulin sensitivity study 2. Improvement was assessed by using the Frequently Sampled Intravenous Glucose Tolerance Test.Results: The greater omentum, which weighed 0.82 kg (95% confidence interval: 0.67-0.97), was removed from subjects who had omentectomy in both studies. In study 1, there was an approximate 2-fold increase in muscle insulin sensitivity (relative increase in glucose disposal during insulin infusion) and a 4-fold increase in hepatic insulin sensitivity 12 months after RYGB alone and RYGB plus omentectomy, compared with baseline values (P<.001). There were no significant differences between groups (P>.87) or group x time interactions (P>.36). In study 2, surgery had no effect on insulin sensitivity (P=.844) or use of diabetes medications.Conclusions: These results demonstrate that decreasing VAT through omentectomy, alone or in combination with RYGB surgery, does not improve metabolic function in obese patients.

KW - Adult

KW - Blood Glucose/metabolism

KW - Cardiovascular Diseases/blood

KW - Diabetes Mellitus, Type 2/etiology

KW - Female

KW - Gastric Bypass

KW - Glucose Clamp Technique

KW - Glucose Tolerance Test

KW - Humans

KW - Insulin/blood

KW - Insulin Resistance

KW - Intra-Abdominal Fat/metabolism

KW - Laparoscopy

KW - Lipectomy/methods

KW - Liver/metabolism

KW - Longitudinal Studies

KW - Male

KW - Middle Aged

KW - Muscle, Skeletal/metabolism

KW - Obesity/blood

KW - Omentum/surgery

KW - Risk Assessment

KW - Risk Factors

KW - Time Factors

KW - Treatment Outcome

U2 - 10.1053/j.gastro.2010.04.056

DO - 10.1053/j.gastro.2010.04.056

M3 - Journal article

C2 - 20457158

VL - 139

SP - 448

EP - 455

JO - Gastroenterology

JF - Gastroenterology

SN - 0016-5085

IS - 2

ER -