Q. I heard about a type of bariatric surgery being done in Brazil called ileal transposition surgery that may cure Type 2 diabetes. As I understand it, it involves moving the part of the small intestine called the ileum from the far end of the intestine to the near end, right next to the stomach. Can you comment on the success rate of this surgery and whether it might become available in the United States?
A. Actually, this surgery is already being done in the United States. About five years ago, surgeons at the University of Texas in Houston began developing a trial to pilot this operation, and the first patient had the surgery done in March 2012. Since that time, three other patients have undergone the sleeve gastrectomy with ileal transposition (SGIT) surgery, as it is known.
All of the patients who had this surgery done had lived with diabetes for five or more years, and all had a glycosylated hemoglobin (HbA1c) level, a measure of how much glucose is in the blood, greater than 7.5% (normal is less than 6%) despite being on insulin and at least two oral medicines to treat their diabetes.
We offered these patients the opportunity to have this operation under strict inclusion and exclusion criteria and under the scrutiny of an internal review board and data safety monitoring board. That is, we did it “by the books” to make sure the science was right and safe. All four patients had the operation successfully and without any major complications. All the surgeries were done laparoscopically (meaning that tiny instruments were inserted through small incisions to perform the operation), and the average hospital stay was about three days.
The patients were followed up at one-month intervals for three consecutive months, and then every three months after that. The results were wonderful. The average HbA1c dropped 1.8%. This was a big deal because even with aggressive medication management, a drop of only 1% is extremely hard to accomplish. Seeing a drop this big in such a small amount of time was exciting for the patients and the physicians involved.
What was also very interesting is the way the patients’ bodies responded to meals after the surgery. Most people with Type 2 diabetes have a high fasting blood glucose level, meaning it’s high even when nothing has been eaten for hours. After eating, their blood glucose may go really high in response to the carbohydrate they ate.
In people without Type 2 diabetes, the gut responds to food by producing a hormone called glucagon-like peptide-1 (GLP-1), and this helps to control the level of glucose in the blood. People with Type 2 diabetics are missing this response. We call this enteroinsular impairment.
After the surgery, the patients’ fasting glucose levels fell from an average of 123 mg/dl to 114 mg/dl, and after-meal blood glucose from 189 mg/dl to 113 mg/dl, suggesting a new, appropriate response to eating food. In addition, the GLP-1 response to eating measurably increased. This suggested that the enteroinsular axis was being restored to normal. By three months, three out of the four patients were off all their diabetes medication.
Our experience suggests that the SGIT has a tremendous potential to assist in controlling long-standing Type 2 diabetes that has not been controlled with diabetes medicines, and so far we have seen a trend toward substantial improvement in blood glucose control.