VBLOC: Gastric bypass surgery alternative

Los Angeles, CA

Disrupting the vagus nerve, which runs between the gut and the brain, may supplant obesity surgery.

Weight loss surgery works, but is so invasive and has such unpleasant long-term side effects that it's recommended for only a fraction of the obese population, and even many in that group are reluctant to undergo the surgery. In hunting for a simpler and safer alternative, researchers have zeroed in on a nerve that carries much of the communication between brain and gut.

Disrupting this communication, they believe, could lead to safe, effective and sustained weight loss -- mainly by cutting off signals from the gut that tell the brain it's time to eat. The concept still has to be validated, says Dr. Philip Schauer, immediate past president of the American Society for Metabolic and Bariatric Surgery, a Gainesville, Fla.-based association of U.S. weight loss surgeons, "But if it gives even a modest amount of weight loss, it could be a winner."

Two different methods of disrupting the vagus nerve are now in clinical trials. One method, vagotomy, simply cuts the nerve and permanently disables it. The other, vagal nerve blocking, uses an electric current to periodically confuse the nerve and prevent it from transmitting signals. Preliminary results suggest that both methods help to safely reduce excess body weight by about 20% on average within six months of therapy.

Amid the complex set of muscles, nerves and organs that team up to regulate body weight, one anatomical feature stands out: the vagus nerve. Running from the brain through the esophagus and branching out to reach nearly every part of the digestive system, this nerve plays a key role in weight gain.

When the stomach is empty, the vagus nerve informs the brain and triggers the feeling of hunger. When the stomach contains food, the vagus tells the brain and relays back the brain's commands to secrete stomach acid to help digest the food. The brain's control of the passage of food through the digestive system also relies on the vagus nerve. In short, without the vagus, we would get less hungry, and food would stay longer in the stomach.

The vagus nerve does even more than that. While food is being digested, the brain tells the pancreas to make insulin, a hormone that helps store energy from food in fat tissues. That command passes through the vagus nerve. So too does another that instructs fat tissues to grow by absorbing more nutrients. "Everything this nerve does is designed to make you take up energy and put it into your fat," says Dr. Robert Lustig, a pediatric endocrinologist at UC San Francisco and one of the lead investigators in a 30-patient clinical trial of vagotomy for weight loss. "It's your energy storage nerve." Read more VBLOC: Gastric bypass surgery alternative

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UC Irvine tests VBLOC implant

Irvine, CA

A weight-loss device placed under the skin is being tested at UC Irvine, KNBC's Dr. Bruce Hensel reported.

College student Jeff Collins, 24, has struggled with his weight his entire life despite trying everything from dieting to weight loss drugs.

"I've been fat, thin, fat, thin, all my life," Collins said.

When medication failed Collins, he considered gastric stapling or bypass until he heard the downsides.

"I went to an information session with 100 other people. They said there was a 1 percent mortality rate with the operation, and I looked around the room and realized one of us in this room would die. That scared me," Collins said.

What didn't scare Collins was a study at UC Irvine on a new weight loss device called VBLOC.

"The VBLOC's completely different. It doesn't alter the anatomy. It doesn't restrict the quantity of food you eat. Essentially, it actually inhibits the signal that runs between the stomach and the brain," said Dr. Ninh Nguyen of UC Irvine Healthcare.

According to VBLOC researchers, two tiny parts are placed under the skin. One turns the other on and it blocks signals to the nerve, which may control hunger signals to the brain.

Results have varied and the device's makers said, "The results of this study and this patient are not a claim for the potential effectiveness of VBLOC Therapy."

Although Collins had his procedure in January, both he and the researchers don't know if he's in the active group that had the device turned on or the inactive group

"I think it is on," Collins said. "I feel a change in my eating habits. I mean, before the surgery I could go to McDonald's and get a super-sized meal and eat all of it and still not feel full. Now, if I try to order it, I feel full before eating everything."

"Some preliminary data from outside the U.S., particularly Australia and Mexico, have shown that the excess weight loss at about six months is relatively good, (and) about 22 percent of excess weight loss at six months," Nguyen said.

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VBLOC implant therapy in a nutshell

Stomach signals: In VBLOC therapy, two electrodes are surgically implanted at the top of the stomach to block signals from the vagus nerve. In the illustration above, green arrows indicate neural signals traveling from the brain to the digestive system, while blue arrows indicate signals traveling from the stomach and intestines to the brain. A small regulator (shown at right) that controls the frequency and amplitude of electrical signals is implanted beneath the skin and connected to the electrodes (shown here in gray) via wires. The electrical signals can be changed at the physician’s office via a wireless controller. The device is currently being tested in clinical trials and has not yet been approved by the FDA. Credit: Enteromedics

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VBLOC implant: Gastric bypass surgery alternative

Researchers believe that they might be able to combat obesity by blocking the nerve that helps regulate digestion, the vagus nerve.

An implantable device that uses electrical signals to block the vagus nerve, which helps regulate digestion, has shown early success in clinical trials. The experimental therapy, developed by Enteromedics, a medical-device company based in St. Paul, MN, is part of a growing trend to develop alternatives to gastric bypass surgery, an often highly successful but invasive procedure to curb obesity.

"We need an approach to this that is safer than current alternatives and efficient to perform," says Christopher Thompson, a surgeon at Brigham and Women's Hospital who tests new surgical tools and methods.

As the obesity epidemic booms, so has the number of people undergoing gastric bypass surgery, a procedure in which the stomach is surgically reduced to about the size of a lemon. The American Society for Metabolic and Bariatric Surgery estimates that gastric bypass rates have doubled in the United States in the past five years, from about 100,000 in 2003 to approximately 200,000 in 2007.

While gastric bypass often leads to dramatic weight loss, only a small percentage of people eligible for the surgery--those with a body mass index (BMI) of more than 35--actually choose to do it. That may be because the procedure comes with some serious risks and is irreversible, requiring permanent dietary restrictions and nutritional supplements. "Many people who really need the procedure don't seek out medical attention because they're worried about potential medical complications," says Thompson. "We're only treating a small fraction of eligible patients."

A new option is on the horizon. At a neurotechnology conference in Boston last week, Enteromedics described positive preliminary results from a European trial of its vagal blocking therapy, called VBLOC.

The device uses an electrical stimulator to block signals from the vagus nerve, which connects the brain to the gastrointestinal organs, regulating hormones and other factors involved in satiety and hunger. "It controls how the stomach expands when we start to eat," says Mark Knudson, chief executive officer at Enteromedics. "If it doesn't expand, we become full after a few bites."

In the procedure, two small electrodes are laparoscopically implanted next to vagal nerve fibers at the top of the stomach. A regulator implanted under the skin sends high-frequency pulses of electricity to the electrodes, which are thought to block the signals coming from the vagus nerve. While scientists don't know exactly how it works, they theorize that the device blocks signals that would normally tell the stomach to expand to accept food, as well as trigger the release of digestive enzymes and gastric acid, potentially slowing digestion. Many patients report feeling less hungry and feeling fuller earlier, says Knudson.

An analysis of nine patients who were among the first to receive the implant shows that they lost almost 30 percent of their excess body weight after nine months. And preliminary data from a larger group indicates that following the procedure, patients ate an average of 500 fewer calories per day. "That's less than you'd see for a lap band or a gastric bypass, but it's still pretty good," says Janey Pratt, a surgeon at Massachusetts General Hospital, in Boston. More >>

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Volunteers wanted in obesity study: VBLOC, gastric bypass surgery alternative

Stanford researchers to test alternative to risky surgical procedures

Stanford University is starting a clinical research study on obesity that would give patients an alternative to invasive surgical procedures. The study, called Empower, will evaluate the safety and efficacy of an experimental method, called VBLOC Therapy, that periodically stops the body's neural messages of hunger and fullness from reaching the brain.

Empower is searching for recruits from around the Bay Area. Applicants must be between 18 and 65, with a body mass index between 35 and 45.

A 2001-2004 health and nutrition study by the National Institutes of Health found that about 66 percent of American adults are overweight and nearly one-third are obese.

"About 12 million Americans qualify for the study," said Dr. John Morton, associate professor at Stanford Hospital and Clinics.

"Obesity is now a global medical concern," added Morton, who is leading the study, "and is considered to be one of the leading causes of preventable death, second only to smoking."

Obesity is related to serious health risks such as hypertension, high cholesterol, sleep apnea and osteoarthritis as well as certain types of cancer.

To avoid these health problems, patients often turn to gastric bypass surgery, a major abdominal procedure with high risks and moderate benefits, according to Morton.

"No clinical or medical complications occurred" during international VBLOC trials, said Morton, who added that he has recorded no patient deaths in 1,200 gastric bypass
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operations.

Through the use of implanted electrodes, the VBLOC Therapy blocks the vagus nerve, intermittently stopping the signals of hunger and satisfaction carried from the stomach to the brain.

After a trial VBLOC study conducted outside the United States showed nine participants had excess weight loss of 29.5 percent after nine months, the Food and Drug Administration approved Morton's clinical study.

Participants can expect a comprehensive trial study as they meet with staff during 43 clinical visits that include nutritional and psychological counseling over the course of five years.

To learn more about the study, visit http://www.empowerstudy.com or call 866-978-2562.

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VBLOC: Gastric bypass surgery alternative

New York, NY

There may be new hope for people struggling with obesity.

It's called VBLOC therapy and it works by stopping the impulse to overeat by blocking the vagal nerves. Those nerves communicate feelings of hunger and fullness from the brain to the stomach.

With the new approach, doctors insert a VBLOC device just beneath the skin. It's a receiver. Electrodes are hooked up to the vagal nerves. And the patient wears a belt that transmits electronic impulses to confuse or block the nerves' signals. The desired result - pangs of hunger are reduced, and patients eat less.

A nationwide trial of VBLOC therapy is under way.

The treatment is considered less invasive than bariatric surgeries, which usually involve shrinking the stomach by wrapping a tight band around it - a so-called lap-band - or bypassing large sections of the stomach altogether and going directly to the rest of the digestive tract - commonly referred to as gastric bypass surgery.

On "The Early Show" Friday, Dr. Scott Shikora, chief of bariatric surgery at Tufts University Medical Center in Boston and one of the current study's principal investigators, showed a VBLOC device, explained how it works, and outlined the new therapy's possible benefits.

And Jeff Collins, who had the device implanted in Los Angeles in December, said he's lost 20 pounds and now weighs 285. "I would recommend it to anybody who's (trying) to lose weight."

"The risk with the other two gastric bypass procedures right now is too high, especially with people my age," Collins said.

"With gastric bypass," Shikora pointed out to CBS News, "we're dividing the stomach and bowel, and it's fraught with potential risks, such as infection. With the VBLOC, we're not dividing the stomach, we're simply attaching electrodes to two very prominent nerves."

But, he cauutioned, "Remember: This is research. We don't know yet how this device will perform, how consistent it will be long-term. It could prove to be a better alternative for some. Also, gastric bypass has a 40-year track record. We know it works."

Shikora says it takes 45 minutes to an hour to implant the device and patients can often go home the same day. More >>

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