07/11/2007

Nerve-snip could spur weight loss

By Lauran Neergaard
The Associated Press

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.

"By no means do I think this is a panacea,” cautions Dr. Robert Lustig of the University of California, San Francisco. "But I think this will be a rational alternative for a cadre of patients that are sort of in the middle there. With as much obesity as we have in this country, that's a big middle.”

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, which can produce life-altering weight loss with diet and exercise. But there are varying degrees of pain and risk, so doctors are searching for alternatives.

Enter the vagus nerve, which snakes from the brain to the abdomen. 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 great relief. Once better acid-reducing medications came along, this arduous operation was abandoned.

Yet surgeons noticed, and subsequent animal studies confirmed, that these vagotomies could trigger weight loss. 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. Of the 11 who are a year past surgery, all but one are shedding pounds. They suffered no serious side effects, and went home hours later with little pain.

"I have my doubts that vagotomy alone is going to be a significant weapon,” says Dr. Neil Hutcher of Bon Secour St. Mary's Hospital in Richmond, Va., 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 is about to recruit 60 more patients headed for band surgery, giving half a vagotomy as well.