Metabolic Surgery for Diabetes Treatment: Choosing the Type of Operation

By Alan L. Rubin

A number of operation choices are available to diabetes patients, all of which are considered safe. Some are more effective than others. The following sections describe a few of the most common.

They’re divided into restrictive operations and malabsorptive operations. The restrictive operations reduce the food you can eat but don’t interfere with your absorption of food. The malabsorptive operations interfere with the absorption of food by your intestines. All the operations are done laparascopically, which means the surgeon makes very small incisions in your abdomen and inserts long, slender operating instruments through these incisions.

As a result, you have much less postoperative discomfort and recover faster compared to an operation where your abdomen is opened. An even newer type of operation is single incision laparoscopic surgery. The surgeon makes a single incision through the belly button, avoiding the four to five incisions of traditional laparoscopic surgery. There is a better cosmetic result, faster recovery, and less pain.

The three operations in the following sections tend to be the most commonly performed at the Bariatric Centers of Excellence. A number of other types of metabolic surgery have been developed including biliopancreatic diversion with or without duodenal switch, vertical banded gastroplasty, jejunoileal bypass, and others. These other operations have been associated with short-term and long-term complications, particularly lack of absorption of key vitamins and minerals. However, if the more common operations aren’t successful for one reason or another, these other operations may be considered as a next step.

Adjustable gastric banding (AGB)

The adjustable gastric banding (AGB) is a restrictive operation. An adjustable band is placed close to the top of your stomach, creating a small upper pouch and a much larger lower pouch. The normal stomach is about the size of a football. The small upper pouch is the size of a golf ball. The upper pouch can hold very little food. You get full quickly, and your feelings of hunger disappear when the pouch is full. In addition, a nerve called the vagus nerve runs along the stomach. The band squeezes the nerve when the pouch is full, sending a signal to your brain to stop eating.

The band is connected via a tube to an injection port under the skin. A salt solution inflates the band to the extent needed to promote sufficient weight loss.

Patients who have AGB tend to lose less weight than those who have a malabsorptive procedure. However, to lose weight, you must follow a strict diet. Christine Ren-Fielding, MD, of the New York University Langone Weight Management Program has published a study of 100 people with diabetes who have had AGB. Forty percent had complete remission of their diabetes, 40 percent had improvement, and 20 percent had no change or worsened after five years. Improvement correlated with the amount of weight lost.

Advantages of AGB include the following:

  • It induces excess weight loss of 40–50 percent.

  • It involves no cutting of the stomach or rerouting of the intestines.

  • It requires a shorter hospital stay, usually less than 24 hours.

  • It’s reversible and adjustable.

  • It has the lowest rate of postoperative complications.

  • It has the lowest rate of vitamin and mineral deficiencies.

Here are the disadvantages:

  • The patient experiences slower weight loss.

  • More patients fail to lose 50 percent of excess weight.

  • It leaves a foreign object in the body.

  • It has the highest rate of reoperation.

Roux-en-Y gastric bypass (RYGB)

The Roux-en-Y gastric bypass (RYGB) is mostly a restrictive procedure but has some malabsorption associated with it. The stomach is stapled to create a small upper pouch totally closed off from the larger lower pouch. The upper pouch is attached to the small intestine so that the upper third of the intestine is bypassed, resulting in some malabsorption. The larger lower part of the stomach empties into the intestine, but no food can get to it so only digestive juices flow through it.

Anita Courcoulas, MD, of the University of Pittsburgh Medical Center reported that patients who had a RYGB operation had a 27 percent weight loss compared to 17 percent for those who had AGB. RYGB may be the operation of choice for the person with type 2 diabetes who has had it longer and it isn’t well controlled.

RYGB has these advantages:

  • Long-term weight loss is significant, up to 60 percent.

  • Favorable changes in intestinal hormones occur.

The disadvantages include

  • It’s the most complicated of the surgeries.

  • It may result in vitamin and mineral deficiencies.

  • It has a longer hospital stay.

Vertical sleeve gastrectomy (VSG)

VSG is another restrictive operation. The stomach is divided so that the part left in the patient is a tube that isn’t much wider than the intestine into which it empties, about 25 percent of the size of the original stomach. The operation results in an early feeling of fullness similar to the AGB. The other part of the stomach is removed, and absorption isn’t affected.

A study published in the Journal of Visceral Surgery in April 2013 compared the effects of AGB, RYGB, and VSG in terms of weight loss and postoperative complications and death with 26,558 operations evaluated. The conclusion was that VSG is midway between AGB and RYGB. The weight loss is less than RYGB but more than AGB. Complications and death are less than RYGB but more than AGB. Despite the fact that VSG doesn’t cause as much weight loss as RYGB, sleeve gastrectomy has become the most popular method of weight loss surgery in the United States, surpassing laparoscopic gastric bypass, which had been the most common procedure for decades, as of November 2014. In 2013 in the United States, VSG accounted for 42.1 percent of the bariatric procedures performed, followed by gastric bypass (34.2 percent), gastric band (14 percent), and others (1 percent).

VSG may be best in the earlier stages of diabetes. Five years after VSG only 10 percent of patients with more severe diabetes taking insulin were still in remission, whereas 59 percent of those taking oral antidiabetic drugs were in remission and 81 percent of those who were about to develop diabetes but not yet on drugs hadn’t developed the disease. This was the case even though the severe diabetics lost as much weight from the operation as the less severe cases.

Advantages of this surgery include

  • There is rapid and significant weight loss.

  • There is no foreign body or rerouting of the intestine.

  • It has a brief hospital stay of two days.

  • Favorable changes in intestinal hormones reduce hunger.

Some of the disadvantages are

  • It’s not reversible.

  • Long-term vitamin deficiencies may occur.

The longer an individual has type 2 diabetes, the more resistant he or she is to remission.