Gastric balloon to treat obesity: a double-blind study in nondieting subjects

A new treatment for obesity is the gastric balloon, which is inserted into the stomach and then inflated. By occupying part of the stomach volume, the balloon is intended to decrease food intake. The approach is much less invasive than gastric stapling, a surgical procedure in which part of the stomach is stapled off so that the functional stomach capacity is reduced. While over 25,000 patients received the gastric balloon from 1985 to 1988, its effectiveness had not been adequately tested. Several recent studies reported that the balloon offered no benefit over the effect of dieting alone. These results may have been due to the small inflation volume of the balloons, which was 200 milliliters (ml), or approximately 7 ounces. This study tested the efficacy and safety of the silicone-rubber balloon in 10 obese persons who were not dieting (average age 35 years). All were fitted with a gastric balloon, which was inflated to 400 ml for one month and deflated and left in place for another month. The order of these periods was varied, however, and neither the subjects nor the technicians collecting food intake and weight data knew when the balloon was inflated or when it was collapsed. During balloon inflation, a small, significant weight loss was achieved during the second and third weeks of the month-long period; in the fourth week no significant weight loss occurred. During balloon inflation, the time it took for the stomach to empty was slowed, which affected blood levels of glucose, insulin, glucagon and cholecystokinin; the latter three are hormones involved in digestion. During the inflation phase, one patient developed a small stomach ulcer, which healed. Use of the inflated gastric balloon, without dieting, did not result in significant weight loss after the entire one-month period. Thus 400 ml balloon inflation was no more effective than the 200 ml version tested by other researchers. The authors suggest further study with larger balloon volumes. However, even with bigger balloons, subjects may adapt over time and regain the ability to eat as much as they desire, as may have happened during the fourth week of balloon inflation in this study. (Consumer Summary produced by Reliance Medical Information, Inc.)