Weight-Loss Surgery Alternative?
Stomach Pacemaker May Be Low-Risk Option
WebMD News Archive
Oct. 16, 2003 -- A new "pacemaker" implanted in the stomach may offer obese people another surgery alternative. Early results of the stomach pacemaker show that most patients lose a significant amount of weight.
Researchers say the stomach pacemaker could replace traditional weight-loss surgery in some obese people.
The stomach pacemaker -- known technically as the Implantable Gastric Stimulator -- helps people feel full. And early results show that 80% of patients lose weight after having the device implanted.
The stomach pacemaker is put into place through laparoscopic surgery -- where surgery is performed through several small holes in the abdomen rather than a large opening. An electric lead is implanted in the wall of the stomach and is connected to an electric programming unit that is inserted under the skin of the abdomen.
Exactly how the stomach pacemaker helps people lose weight is unknown, says Scott Shikora, MD, assistant professor of surgery at Tufts University School of Medicine.
It causes people to feel full earlier, but researchers don't know whether this is caused by stimulation of nerves, inhibition of hormones, or stimulation of the muscle of the stomach itself, he tells WebMD.
However, the stimulator offers a novel approach that does not alter gastrointestinal anatomy -- as in traditional weight-loss surgery -- and has been shown to be safe in 450 patients worldwide, according to the researchers.
Shikora and Michael Tarnoff, MD, presented their research at the North American Association for the Study of Obesity annual meeting.
In their study, the stimulator was surgically placed in 30 men and women -- average age 39 -- who were more than 100 pounds overweight. The study was funded by Transneuronix Inc., the manufacturer of the Implantable Gastric Stimulator.
Two weeks after surgery, the generators were activated. All 30 patients were successfully implanted with the device with no complications. Electrical parameters were adjusted for the patients based on their individual responses.
Results were available for 15 patients. Of those, 80% lost weight after about 10 months. On average, the amount of weight loss was 19% of excess weight.
Other findings include:
- A 15% drop in appetite before meals
- A 60% increase in fullness between meals
- A 90% increase in satiety at the end of a meal
The stimulator system may evolve into a low-risk and effective alternative to the currently popular weight-loss surgery procedures to treat obesity, Shikora and colleagues conclude.
But it's not likely to replace weight-loss surgery in most people.
For some patients, the stimulator is as good as other types of weight-loss surgery, but overall it is probably going to be less effective, Shikora says. "You are trading a bit of weight loss for safety since [the stimulator] doesn't alter the gastrointestinal tract the way other procedures do."
According to Shikora, a screening algorithm that might accurately predict who this procedure will work for is currently under development.
"The screening algorithm was found to separate responders from nonresponders, and responders had weight loss very much comparable to the other procedures, although this is still investigational," he says.
"We are doing what we hope will be the pivotal study this winter involving approximately 120 patients at five or six research centers. If that demonstrates good results, we will probably get FDA approval within the next couple of years," he says.
With reporting by Emma Hitt, PhD.