Bariatric Surgery isn’t just for weight loss anymore. It’s been shown to be possibly curative of type 2 diabetes even in the absence of major weight loss following the surgery. Here’s the rundown on how it works.
As a nation, we’re fattening up at a rapid clip. In 2005, almost two-thirds of us were overweight, a third were obese and approximately five percent were “morbidly obese.” Given that obesity is associated with hypertension, diabetes, high cholesterol, sleep apnea, heart disease and stroke, it’s possible that obesity may actually lead to a decline in life expectancy in the U.S. during the 21st century.
For those of us who just can’t seem to lose weight with diet and exercise, bariatric surgery is increasingly being considered as an option. In Greek, “barys” means “heavy” and “iatros” means healer, and that’s what the surgery aims to do. And it’s becoming increasingly popular.
Between 1998 and 2004, gastric bypass surgeries among patients aged 55 to 64 grew by 2000 percent, and now even adolescents are undergoing the procedure. It’s also becoming less dangerous and a bit less costly than it used to be.
All bariatric procedures reduce calorie intake by altering the gastrointestinal tract, but there are two basic types: restrictive or malabsorptive. Restrictive procedures cut down on the amount of food you can take in by tying or stapling off a little portion of the stomach, thus creating a miniature stomach, and leaving only a narrow outlet from which the food travels into the rest of the stomach and out in the normal manner.
The stomach is reduced from a four-pint capacity to about a half-cup, and the lower outlet of the pouch is only about ½ inch in diameter. Malabsorptive procedures, also called gastric bypasses, bypass about two feet of the small intestine, the originally twenty-foot long tube where nutrient absorption occurs. Consequently, the food travels a shorter route, and fewer calories are absorbed.
Restrictive procedures include stomach stapling, also called vertical-banded gastroplasty (gaster means stomach, and plasty means molding or forming). In that process, a line of staples creates the small pouch, and then a band is tied around its end to reduce the speed with which food can leave. It’s not very common these days. Another method is adjustable gastric banding, which uses a band to create a miniature stomach just below the esophagus, or gullet. The band is connected to a little saline reservoir beneath the skin.
As a result, the tightness of the band can be adjusted by pumping saline into it to make it snugger or withdrawing saline to make it looser. The process is called a lap-band when it is applied via laparascopic surgery, that is, by making five little holes in the abdomen through which tools are threaded to do the surgery. Another restrictive procedure is the vertical restrictive (sleeve) gastrectomy (ectomy means surgical removal) in which the stomach is cut into a tube shape and then sewed up to form a narrow sleeve that is not much thicker than the intestine into which it empties. This method isn’t used much these days.
If you eat too much after a restrictive operation, or if the little exit hole from your stomach becomes blocked, you are likely to end up vomiting. Another common risk of adjustable gastric banding is a break in the tubing that allows the salt solution to leak out, requiring another operation to repair. Rarely, patients experience infections and bleeding. On the other hand, between 15 and 20 percent of vertical banded gastroplasty patients may have to undergo a second operation for a problem related to the procedure.
The fact is that many times, people who have only had restrictive procedures don’t manage to keep their weight off long-term. Consequently, combination restrictive-malabsorptive procedures are more common nowadays. The most popular of these is called proximal Roux-en-Y gastric bypass (RYGB). It involves stapling the stomach to create a small egg-sized pouch with no outlet. Then the small intestine is cut into two pieces.
The lower end, called the Roux limb, is brought up to the little stomach and sewed to it to allow food to go out. The other cut end is sewed back onto the intestine a ways down, to allow bile and pancreatic secretions into the small intestine so that digestion can proceed and nutrients can be absorbed.
Restrictive procedures such as vertical-banded gastroplasty and adjustable gastric banding result in long-term weight loss of approximately forty percent of excess body weight, whereas RYGB and biliopancreatic diversion (a complicated and less common malabsorption procedure) result in an average long-term weight loss of sixty percent. In biliopancreatic diversion, however, you end up with such a short intestine that getting enough vitamins and minerals becomes a problem.
Although RYGB is currently the most popular form of bariatric surgery, it does carry some risk. The risk of actually dying can be up to one percent, and the risk of serious complications is as high as ten percent. The leading cause of death is pulmonary embolism caused by deep vein thrombosis (a blood clot deep in a leg vein that breaks loose and travels to the lungs where it blocks a lung artery).
The risk for this is controlled by wearing constrictive stockings on the legs and taking anti-coagulant medication. Pulmonary embolism, leaks in the surgical connections, and respiratory failure together account for eighty percent of deaths in the first thirty days after surgery.
Complications in the early post-operative period include splitting along the suture lines, leaks from staple breakdown, and ulcers. Wound infections are a concern, as well as narrowing of the stomach pouch outlet. More than one-third of patients who have gastric bypass surgery develop gallstones.
Is bariatric surgery right for you? The surgery is usually reserved for men who are at least a hundred pounds overweight and women who are at least eighty pounds overweight. If you are somewhat less overweight, surgery still might be an option if you also have diabetes, heart disease or sleep apnea. There are more than thirty obesity-related medical conditions that can damage your quality of life and cause early death, so losing weight is definitely good for your health.
In people who have type 2 diabetes, gastric bypass surgery has proven curative in some studies. Researchers initially thought that weight loss caused the remission of type 2, but new findings are pointing to hormonal and metabolic changes caused by the surgery. One analysis reported that type 2 diabetes was completely resolved in 76.8 percent of patients following bypass surgery.
Another recent analysis showed that 84 percent who underwent Roux-en-Y gastric bypass (RYGB) experienced complete reversal of their type 2 diabetes. Most of them stopped their oral meds or insulin before they even left the hospital, so the remission was apparently not due to weight loss alone.
As a result, gastric bypass surgery is being explored as a cure for type 2 diabetes in normal weight or moderately overweight people. Recently, the RYGB procedure was used on two mildly overweight patients. Within a month post-surgery, these patients had dramatically lower fasting glucose, fasting insulin, and A1c’s.