Dec. 30, 2003 -- Doctors in the U.S. may soon have a new, high-
Dec. 30, 2003 -- Doctors in the U.S. may soon have a new, high-tech weapon in the battle against obesity.
New research shows an electronic pacemaker implanted under the skin and connected to the stomach can help morbidly obese people lose weight without the side effects of other drastic weight-loss strategies, such as bariatric surgery or medications.
The study suggests that gastric pacemakers work by targeting hormones in the body associated with obesity and helping people eat less. But more research is needed to determine exactly how these pacemakers work.
Although the device is still considered experimental and not approved for use in the U.S., the device is already on the market in Europe, and researchers say gastric pacing may one day provide a low-risk alternative to bariatric surgery, such as gastric bypass or stomach stapling, for severely obese individuals.
"Gastric pacing is a novel approach to treat obesity: less aggressive than the usual surgical procedures and with no side effects compared with long-term drug therapy or bariatric surgery," write researcher Valerio Cigaina, of Venice Hospital in Venice, Italy, and colleagues in the December issue of Obesity Research.
New Clues on How Stomach Pacemakers Work
Previous studies of gastric pacemakers have shown that the devices aid in weight loss in humans and animals, but the mechanism is unclear. For example, the weight loss associated with pacemakers may be the result of changing nerve stimulation activity of the stomach, inhibiting hormones related to food intake and metabolism, or stimulating the stomach muscle itself.
In this study, Italian researchers looked at how the device affected levels of hormones in the blood associated with satiety and obesity in 11 morbidly obese men and women (average BMI of 46) who were treated with gastric pacing.
The pacemakers were surgically implanted via either minimally invasive laparoscopic surgery or open surgery under general anesthesia. The device consists of electric wires placed in the wall of the stomach and connected to an electric pacer, about the size of a silver dollar, that is inserted under the skin of the abdomen.
After the gastric pacemaker was implanted, the participants were not prescribed any specific diet, but they were encouraged to eat three meals a day or less and avoid snacks and high-calorie beverages and alcohol.
Six months after the device was implanted and activated, researchers found that gastric pacing resulted in a significant weight loss, an average of about 23 pounds per person.
The study also showed that levels of a hormone associated with obesity called leptin were lower when the pacemaker was in use, which the authors say may have been the result of the loss of body fat. Leptin is secreted by fat cells and acts on the brain to decrease food intake and increase metabolism. Obese people are thought to be resistant to leptin.
But researchers say they were surprised to find that levels of hormones normally released after eating that trigger feelings of fullness, cholecystokinin (CCK) and somatostatin, were actually reduced compared with measurements taken before the pacemaker was implanted.
Researchers say the participants reported feeling more satisfied after and between meals even though the levels of these hormones were lower. Therefore, researchers suggest that gastric pacing may work by increasing the body's sensitivity to these hormones and help them feel fuller and eat less, but more research is needed to prove this theory.
"Further studies are needed to elucidate associations between gastrointestinal hormones, satiety, and weight loss during treatment with gastric pacing," conclude the researchers.
