WASHINGTON - An old ulcer operation is getting new attention as a possible alternative obesity surgery: a quick snip of a nerve that helps control hunger.
It's far from clear if cutting the vagus nerve really helps - initial pilot studies in a few dozen patients have just begun. Skeptics abound, and even proponents say it wouldn't lead to nearly as much weight loss as more traumatic operations that shrink the stomach and reroute intestines.
It's part of a hunt for middle-ground options for people scared of today's surgery, or those not quite fat enough to qualify for it.
More than 177,000 people underwent obesity surgery last year, according to the American Society for Metabolic and Bariatric Surgery. The most popular method is gastric bypass, stapling the stomach to create a tiny pouch. Options include placing an adjustable band around the stomach, or cutting off the stomach's side and rerouting the intestines.
Surgery can produce life-altering weight loss, if recipients adhere to diet and exercise advice, but each method comes with varying degrees of pain and risk, including a rare chance of death. So doctors are searching for alternatives.
Enter the vagus nerve, which snakes from the brain to the abdomen, with fibers reaching into multiple organs with different effects. Among them: The nerve spurs gastric acid production, and in the 1970s, surgery to cut where it attaches to the front and back of the stomach brought ulcer sufferers relief.
Yet surgeons at the time noticed, and subsequent animal studies confirmed, that those vagotomies could trigger weight loss. In addition to a less acidic stomach's slower digestion, the vagus helps control appetite-stimulating brain hormones and signals our bodies to store more fat, Lustig explains.
Since doctors today can snip the nerve far less invasively, it was time to test in the obese.
Thirty patients had a vagus snip at UCSF or the University of Rochester. The study isn't complete. But of the 11 who are a year past surgery, all but one are shedding pounds, losing an average of 18 percent of excess weight so far, Lustig and Rochester's Dr. Thad Boss reported at last month's bariatric society meeting.
They suffered no serious side effects, and went home hours later with little pain.
"Every patient who had the vagus nerve cut says they're not hungry," adds Lustig - although the one who didn't respond got hungry again six weeks after surgery, perhaps because the nerve healed.
That's less than half the weight loss of standard surgeries, warns Dr. Neil Hutcher of Bon Secour St. Mary's Hospital in Richmond, Va., and a past president of the bariatric society.
"I have my doubts that vagotomy alone is going to be a significant weapon," says Hutcher, who often cuts the nerve during standard gastric bypasses for a different reason - to help those patients avoid the side effect of heartburn-causing acid buildup.
But, when Greensboro, N.C., surgeons added a vagotomy to 25 patients getting bands on their stomachs, the nerve-snip seemed to make that usually more modest operation about as effective as a gastric bypass - with 43 percent loss of excess weight at six months, and counting.
For a more rigorous study, Rochester's Boss is about to recruit 60 more patients headed for band surgery, giving half a vagotomy as well.
The pilot studies were funded by a startup medical device company called EndoVx Inc. that hopes one day to further simplify vagotomies, cutting the nerve by beaming high-intensity ultrasound waves down the throat.
Other doctors are testing whether implants that treat epilepsy by stimulating the vagus nerve also might trigger weight loss, with mixed results so far.
For now, Boss stresses that vagus nerve-snipping remains highly experimental. He and Lustig will track their 30 patients for 18 months to check if ultimate weight loss is enough to warrant further study, and who responds best.
The goal is to help people such as Garth Michaels of Walnut Creek, Calif., who twice backed out of standard obesity surgery, fearful of side effects and a long recovery. Thirteen months after he volunteered for the vagotomy experiment, he has dropped 66 pounds, to 246.
That's a much more gradual loss than with regular surgery, but Michaels says having his hunger curbed help him finally learn to exercise. He spends a half-hour on an exercise bike most days. And he learned to avoid former diet saboteurs - french fries, sweets - that caused foul burping after his vagotomy, in favor of fruits and vegetables.
"I will lose more, there's no doubt about it," says Michaels, 56, whose goal is 175 pounds. "It has given me such hope."