Bariatric surgery by itself isn't enough
It saves lives, brings long-term weight reduction and fights diabetes. But it still has complications.
A band is wrapped around the stomach. (Anne Cusack, Los Angeles Times / May 30, 2008)
After years of question marks, studies now show the surgery saves lives, sustains long-term weight loss and combats -- maybe even reverses -- diabetes. But although it's much safer today, it still results in the death of 1 in 200 patients and can result in complications such as blood clots, hernias or bowel obstructions. Patients can end up back in the hospital to repair intestinal leaks that can lead to serious infection.
Because of these complications, a National Institutes of Health panel of experts has recommended the surgery only for people considered morbidly obese, roughly 100 pounds or more over their ideal body weight. People whose weight is that far out of control face a risk of death from diabetes or heart disease five to seven times greater than those of normal weight.
"These people don't have a lot of options," says Dr. John Morton, director of bariatric surgery at Stanford's Center for Weight Loss Surgery. "When someone is drowning, I throw them a life preserver. I don't have time to build a bridge."
About 14,000 Californians undergo weight-loss surgery each year. But according to American Society for Bariatric Surgery guidelines, more than 1 million Californians qualify medically: those with a body mass index of 40 or more, or 35 or more if they have conditions such as heart disease or diabetes.
The twin remedies to get rid of fat -- diet and exercise -- have proven ineffective for people who are vastly overweight. A cycle takes over. Weight gain leads to problems such as arthritis or difficulty breathing, which makes exercise difficult and eventually, impossible. People sit more, move less and don't burn all the calories they consume. "Once you're in the morbidly obese category, it is very, very hard to lose the weight using nonsurgical means," says Dr. Melinda Maggard Gibbons, a general surgeon and researcher at the Center for Surgical Outcomes and Quality at UCLA.
There are two main surgical options. Gastric bypass surgery diverts food from a stomach that has been reduced from the size of a football to the size of a golf ball, using surgical staples or a plastic band. The most common and successful technique is called the Roux-en-Y procedure, named for the surgeon who invented it and the resulting Y-shape of the reconfigured small intestine. The food from the tiny stomach bypasses more than half of the small intestine, where nutrients and calories are absorbed, and then heads for the large intestine, from where it's eventually excreted as waste.
Stomach-banding surgery, which is reversible, wraps a silicone belt around the stomach, drastically reducing its size, so that as little as a tablespoon of food fits at a time. Both procedures successfully result in weight loss, though more pounds come off, and quicker, with gastric bypass surgery.
"The surgery is anatomy-mandating behavioral change," Morton says. A small or bypassed stomach demands that people eat less. This leads to weight loss, which allows more freedom of movement, which makes exercise possible.
Improvements in surgical options came after years of trial and error. In the 1950s, surgeons experimented with intestinal bypass surgery, leaving the stomach intact but looping out all but about 2 feet of the intestine. People lost weight, but their guts could no longer absorb vital nutrients. Patients suffered episodes of diarrhea 10 to 15 times a day, as well as malnutrition, dehydration, kidney stones and liver problems.
So surgeons largely gave up on intestinal bypass and tried stomach stapling instead. "That had problems," says Dr. David Zingmond, professor of internal medicine at UCLA. "People could re-expand their stomachs."
It wasn't until the early 1990s that gastric bypass surgery began to help people more than it hurt them.
The new techniques have fewer nasty or life-threatening side effects, provided that patients eat small amounts and take nutritional supplements. Still, questions about the procedures' long-term results persisted until 2007, when a Swedish study in the New England Journal of Medicine seemed to settle at least some of them. Researchers followed about 2,000 obese patients who had undergone weight-loss surgery -- either gastric bypass or surgical banding -- and compared them with about 2,000 similarly obese people who didn't have surgery but were counseled in diet and exercise. After 10 years, those who had gastric bypass surgery weighed 25% less; those who had stomach-banding surgery were down about 15%. Those who got traditional diet advice lost no more than 2% of their weight.
It has long been known that people lose a lot of weight at first, then regain some of it. This study showed that a significant amount of weight stayed off -- and for the first time showed that long-term weight loss, even when people remain overweight, is enough to save lives.
There were 129 deaths in the diet-only group, mostly from weight-related heart disease and cancer. The 101 deaths in the surgery group were also largely from heart disease and cancer, though there were half the number of heart attack deaths as for those in the diet group, and fewer deaths in all but one category. That exception was infection, possibly a result of the surgery. Twelve people who had surgery died of infection, compared with three in the diet group.
Even more remarkable to scientists is the finding that both major types of weight-loss surgery can reverse diabetes. In 2004, a review of 130 studies of more than 22,000 patients in the Journal of the American Medical Assn. found that most diabetics who have gastric bypass surgery are cured of diabetes, often within days. "It's a striking benefit," Morton says. "They're off insulin and medication 82% of the time."
A January study in the same journal showed similar results for stomach-banding surgery, though the result in this case can take up to a year. Researchers aren't sure why surgery reverses diabetes, but speculate that it results in a beneficial change in the levels of hormones related to diabetes.
Paul Shekelle, director of the Santa Monica-based Rand Corp.'s evidence-based practice center, which conducts healthcare reviews, said the Swedish study finally convinced him that bypass surgery does save lives. But he's concerned that too many people see surgery as an easy solution to a very difficult problem.
"You've got to make sure that patients understand that this is not like getting your knee repaired," he says. "This is going to make your life different."
Patients won't eat sugar any more, not without risking diarrhea, gas, bloating and cramping. They won't eat large amounts of anything, ever.
And since people who have gastric bypass surgery (as opposed to gastric banding) end up with part of the small intestine bypassed, fewer of the nutrients they eat are absorbed. Though these side effects are significantly better than for the early surgeries, patients will still need vitamin supplements, especially iron, folate, vitamin B12 and calcium, for the rest of their lives. There may also be other deficiencies, for micronutrients, say, that scientists haven't recognized, says Dr. Abhimanyu Garg, director of the division of nutrition and metabolic diseases at the University of Texas Southwestern Medical Center at Dallas.
Patients will also end up in the hospital more often in the years after surgery than in the years before, according to a 2005 study in the Journal of the American Medical Assn. Zingmond, lead author of the study, and colleagues looked at 60,000 Californians who had gastric bypass from 1995 to 2004 and found that 20% were admitted to hospitals the year after surgery, 18% two years after and 15% the third year after. Only about 8% were hospitalized in the year before surgery.
The most common reasons for rehospitalization were complications from the procedure, such as sutures splitting or hernias. "There are a large number of people who come back for a repeat procedure," Zingmond says.
Surgical banding results in complications too, but they are hard to count, Gibbons says. "A fair number of [the bands] have to be removed," she says. "We don't know the number because a lot of them are done as outpatient procedures. We think it's somewhere between 15% and 30%. That's a big deal."
It's not easy to shed even 10 pounds -- but once people are 80, 90, 100 pounds or more overweight, it becomes increasingly difficult. "For those patients, the benefits clearly outweigh the risks," Gibbons says. "But it's not a quick fix. It's a forced lifestyle change."