Myth Buster #3: Vertical Sleeve Gastrectomy Is Not a Metabolic Procedure

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Metabolic Surgery as a term is used throughout this Blog.  Aside from the dramatic weight loss associated with Bariatric Surgery, this is as exciting an effect, often times resulting in remission or resolution of previously difficult to control Diabetes.

Relatively new to the scene of Bariatric surgery as a stand alone procedure, VSG can also impart metabolic effects for those obese patients with concomitant DM2, even without the "intestinal rerouting" associated with the the Gastric Bypass.

More and more studies are coming out showing a favorable  impact of VSG  on Diabetes type 2, which leads to the question of how, and requires taking a look into the physiology beyond the weight loss that imparts this effect.

VSG is typically viewed as a restrictive procedure, whereby 80% of the stomach is removed, creating a column of a stomach along the lesser curve, without the bypassing the normal route of food from the stomach to the small intestine, as is a part of a Gastric Bypass.

Aditionally, studies have borne out the following after VSG:

   *Improved post prandial glucose levels, associated with a potent increase in the early insulin secretory response to nutrients in the GI tract.
   *Circulating GI hormone levels are also affected, with a dramatic increase in GLP-1 post prandially
   *Additional to glucose regulation, Triglycerides in plasma are also reduced, which points to an dual effect on the liver post operatively.

Controversy remains, however, regarding which procedure reigns supreme for its metabolic effect, but in either case, surgery wins out again over medical management.  The data is still unclear, although studies are ongoing longitudinally, regarding which procedure should be performed for which type of patient. However, what is clear is that there is more to a VSG than just a restrictive and associated weight loss component at the heart of this metabolic surgical procedure.

Adapted from L Kaplan, R Seeley, J Harris. "Myth #3:  VSG is not a metabolic procedure".  MARS initiative publication, Bariatric Times Vol 9 No 9. C12-C13.