Glucose metabolism in obese patients with type 2 diabetes mellitus undergoing Standard vs. Long Limb Roux-en-Y-gastric bypass
File(s)
Author(s)
Kamocka, Anna
Type
Thesis
Abstract
Background
Obesity surgery has been shown to be the most effective and durable treatment for type 2 diabetes mellitus (T2DM) and obesity. The optimal length of the small bowel limbs in Roux-en-Y Gastric Bypass (RYGB), the most commonly performed obesity operation in the UK, is debated and variation in practice exists. In this study, called the LONG LIMB Trial, it was hypothesised that a longer biliopancreatic limb length of 150 cm (‘Long Limb’) is superior to a standard biliopancreatic limb length of 50 cm (‘Standard Limb’) in RYGB for the treatment of T2DM.
Methods
This was a two-centre double-blinded randomised controlled clinical trial. Fifty participants with T2DM and obesity were randomised in 1:1 ratio to either a Long Limb or a Standard Limb RYGB. Mixed meal tolerance tests were performed to measure postprandial secretion of active GLP-1 (primary outcome) and other gut hormones, insulin, and glucose excursions and hyperinsulinaemic-euglycaemic clamps to measure insulin sensitivity pre-operatively, within 2 weeks after the surgery and at matched 20% total body weight loss (TBWL). Clinical follow up took place at 3, 6 and 12 months after the surgery.
Results
Within each study group, a significant increase in insulin sensitivity, insulin and active GLP-1 secretion, and reduction in glucose concentrations were observed at 2 weeks post-operatively and 20% TBWL. HbA1c and weight were significantly reduced at all post-operative clinical visits (Standard Limb: HbA1c of 73 ± 17 pre-operatively to 43 ± 10 mmol/mol at one year, p<0.001, with 30 ± 8% TBWL; Long Limb: HbA1c of 76 ± 16 to 41 ± 5 mmol/mol, p<0.001, with 29 ± 8% TBWL), However, no difference between the groups was demonstrated in any of these outcomes nor in the percentage of patients achieving T2DM (Standard Limb 62% vs. Long Limb 77%, p=0.23).
Conclusion
Elongation of the biliopancreatic limb of the RYGB to 150 cm does not result in superior metabolic or clinical outcomes in terms of glucose excursions, insulin and incretin hormones secretion nor insulin sensitivity, T2DM remission or weight loss within 12 months after surgery.
Obesity surgery has been shown to be the most effective and durable treatment for type 2 diabetes mellitus (T2DM) and obesity. The optimal length of the small bowel limbs in Roux-en-Y Gastric Bypass (RYGB), the most commonly performed obesity operation in the UK, is debated and variation in practice exists. In this study, called the LONG LIMB Trial, it was hypothesised that a longer biliopancreatic limb length of 150 cm (‘Long Limb’) is superior to a standard biliopancreatic limb length of 50 cm (‘Standard Limb’) in RYGB for the treatment of T2DM.
Methods
This was a two-centre double-blinded randomised controlled clinical trial. Fifty participants with T2DM and obesity were randomised in 1:1 ratio to either a Long Limb or a Standard Limb RYGB. Mixed meal tolerance tests were performed to measure postprandial secretion of active GLP-1 (primary outcome) and other gut hormones, insulin, and glucose excursions and hyperinsulinaemic-euglycaemic clamps to measure insulin sensitivity pre-operatively, within 2 weeks after the surgery and at matched 20% total body weight loss (TBWL). Clinical follow up took place at 3, 6 and 12 months after the surgery.
Results
Within each study group, a significant increase in insulin sensitivity, insulin and active GLP-1 secretion, and reduction in glucose concentrations were observed at 2 weeks post-operatively and 20% TBWL. HbA1c and weight were significantly reduced at all post-operative clinical visits (Standard Limb: HbA1c of 73 ± 17 pre-operatively to 43 ± 10 mmol/mol at one year, p<0.001, with 30 ± 8% TBWL; Long Limb: HbA1c of 76 ± 16 to 41 ± 5 mmol/mol, p<0.001, with 29 ± 8% TBWL), However, no difference between the groups was demonstrated in any of these outcomes nor in the percentage of patients achieving T2DM (Standard Limb 62% vs. Long Limb 77%, p=0.23).
Conclusion
Elongation of the biliopancreatic limb of the RYGB to 150 cm does not result in superior metabolic or clinical outcomes in terms of glucose excursions, insulin and incretin hormones secretion nor insulin sensitivity, T2DM remission or weight loss within 12 months after surgery.
Version
Open Access
Date Issued
2019-08
Date Awarded
2020-06
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Tan, Tricia
Bloom, Stephen
Sponsor
National Institute for Health Research (Great Britain)
Royal College of Surgeons of England
Publisher Department
Department of Metabolism, Digestion and Reproduction
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)