Gastric bypass surgery doesn't always cure type 2 diabetes

Bariatric surgery may not be the magic bullet that cures type 2 diabetes as previously thought.

While gastric bypass surgery may reverse type 2 diabetes in many obese patients, the disease recurs in one-fifth of them within three to five years, according to a study by Mayo Clinic Arizona in Scottsdale.

Researchers there studied data on 72 obese patients with type 2 diabetes who had Roux-en-Y gastric bypass surgery, a weight-loss procedure that makes changes to your digestive system.

Sixty-six patients, or 92 percent, reversed their diabetes at some point following surgery.

Yet the disease came back in 14, or 21 percent, of the 66 patients within three to five years of having the procedure.

While all patients regained similar amounts of weight, patients whose diabetes did not recur lost more weight initially and maintained a lower average weight during the five years following surgery.

What is Roux-en-Y?

Gastric bypass is the most common type of weight-loss or bariatric surgery in the US, according to Mayo Clinic. Roux-en-Y is just one of many gastric bypass procedures.

In the Roux-en-Y procedure, the surgeon makes a small pouch out of a small portion of the stomach. It gets attached directly to the small intestine, bypassing a large part of the stomach and duodenum.

This surgery helps the patient lose weight because the new stomach pouch, about the size of a walnut, restricts the amount of food the patient can eat.

It also helps by skipping the duodenum during the digestion process, substantially reducing the amount of fat that the body can absorb.

Five-year history is crucial

Researchers found that the longer the duration of type 2 diabetes before surgery, the higher the probability of diabetes recurrence, the researchers found.

Patients in the study who had diabetes for more than five years prior to surgery were 3.8 times more likely to have a recurrence of the disease compared to patients with less than a five-year history of the disease.

"This suggests that early surgical intervention in the obese, diabetic population will improve the durability of remission of type 2 diabetes," said Yessica Ramos, MD, Mayo Clinic Arizona and lead author of the study.

Screening for bariatric surgery candidates

Not everyone is a candidate for weight-loss surgery, however. Careful screening is required to ensure that patients have the best possible chance of success.

These surgeries require that patients make permanent changes to their eating habits and diet. Patients must also make a commitment to exercising regularly to help ensure the long-term success of bariatric surgery, according to Mayo Clinic.

All forms of weight loss surgery are major procedures that have serious risks and side effects. As with all surgeries, risks include excessive bleeding, infection, adverse reactions to anesthesia, blood clots, breathing problems, leaks in the gastrointestinal system, and possibly death.

Depending on the type of bariatric surgery, complications may include bowel obstruction, diarrhea and vomiting, gallstones, hernias, hypoglycemia, malnutrition, stomach perforation, ulcers, and even death.

Sources: Mayo Clinic, Newswise