LONG LIMB

• Research type

  Research Study

• Full title

  Are gut hormone changes why the long-limb gastric bypass is more effective than the standard-limb gastric bypass in improving type 2 diabetes mellitus?

• IRAS ID

  161959

• Contact name

  Stephen/SRB Bloom

• Contact email

  s.bloom@imperial.ac.uk

• Sponsor organisation

  Imperial College London

• Duration of Study in the UK

  3 years, 9 months, 2 days

• Research summary

  Research Summary:
  Obesity is the main cause of the world wide epidemic of diabetes. Weight loss, or bariatric, surgery produces major and sustained weight loss and is being increasingly used to treat obese diabetic patients. There was initial optimism that these procedures might cure all diabetes. However, the gold-standard operation, standard gastric bypass, effectively cures diabetes in only 4 out of 10 patients. To design a safer and more successful procedure we need to understand how bariatric surgery works to improve diabetes. Hormones from the gut are released when we eat food. They control how the body uses the food it absorbs. For example they release the sugar-lowering hormone insulin, and also greatly reduce appetite, which is why one feels less hungry after eating a meal. We have discovered that the good effects of bariatric surgery, and in particular the gastric bypass, are mainly due to increased release of gut hormones, reducing patient s appetite and improving the release of insulin. In this project we will be testing a new procedure called the long-limb gastric bypass. It is designed particularly to be better at helping the diabetes in overweight patients, while being as safe as the currently available standard gastric bypass. We now want to show that this new procedure works better than the standard gastric bypass by causing an even bigger increase in the release of gut hormones and thus of insulin. Using a newly developed technique (mass spectroscopy) we will measure the differences in gut hormone secretion between the new long-limb procedure and the standard gastric bypass far more accurately. In addition we will use a well-tested insulin sensitivity procedure (glucose clamp), both to confirm and to investigate how and why the diabetes is so improved. The measurements we will be making are non-invasive and safe. The only discomfort comes from inserting a cannula to take blood samples. Patients who undergo this long-limb gastric bypass procedure should have fewer complications from diabetes, use fewer medications, and have better overall health and quality of life. If we can show that the benefit of the new modified procedure is indeed due to the increased release of gut hormones and insulin, this may lead to improvements in the design of surgical procedures, will better enable us to offer the right patient the right procedure, and will form the basis for designing improved drug treatments for diabetes

  Lay summary of study results:
  Weight loss surgery, such as gastric bypass, is routinely used to treat people with type 2 diabetes and obesity worldwide. This is because the surgery is effective at lowering weight and improving blood sugar. In some people with diabetes this means that they can come off medications and still have normal blood sugar: this is called diabetes remission. However, the standard gastric bypass surgery only results in diabetes remission in 4 out of 10 patients, and it would be better if we could improve this success rate.

  In this trial a new surgery called Long Limb gastric bypass was tested. It was designed to be better at improving diabetes mellitus than the older ‘Standard Limb’ gastric bypass surgery, while being as safe. It was expected that this new procedure would work better than the Standard Limb gastric bypass by increasing the release of insulin and other hormones from the gut and by improving weight loss and blood sugar over and above the standard operation.

  We found that the Standard and Long Limb operations were equally effective in reducing blood sugar and reducing weight. When followed up to 60 months (5 years) after the surgery, people who had either Standard or Long Limb had similar experiences, with lasting weight loss and improvement in blood sugar levels, but there was no significant difference between the older and the newer type of surgery.

  Our study shows that there does not appear to be a large difference between the two types of surgery: both seem to be similarly effective at helping people to lose weight and improve their diabetes.
  

• REC name

  London - West London & GTAC Research Ethics Committee

• REC reference

  15/LO/0813

• Date of REC Opinion

  29 Jun 2015

• REC opinion

  Further Information Favourable Opinion