Fasting and meal-suppressed ghrelin levels before and after intragastric balloons and balloon-induced weight loss.

BACKGROUND

Intragastric balloons may be an option for obese patients with weight loss failure. Its mode of action remains enigmatic. We hypothesised depressed fasting ghrelin concentrations and enhanced meal suppression of ghrelin secretion by the gastric fundus through balloon contact and balloon-induced delayed gastric emptying.

METHODS

Patients were randomised to a 13-week period of sham or balloon treatment, followed by a 13-week period of balloon treatment in everyone. Blood samples for ghrelin measurement were taken in the fasting state and every 15 min for 1 h after a breakfast meal at the start, after 13 weeks and after 26 weeks. Patients filled out scales to assess satiety and kept a food diary.

RESULTS

Forty obese patients (BMI 43.1 kg/m(2)) participated. At the start, fasting ghrelin values were low with a blunted ghrelin response to a test meal. The presence of a balloon had no influence on fasting or meal-suppressed ghrelin concentrations. Despite a weight loss of 10 % after 13 weeks and 15 % after 26 weeks, fasting ghrelin concentrations did not change; neither did the ghrelin response to a meal. No relation was found between ghrelin and insulin, satiety, intermeal interval, the number of meals or subsequent energy intake. Ghrelin concentrations were more suppressed with greater weight loss or with balloons located in the fundus.

CONCLUSIONS

Ghrelin concentrations did not change by balloon treatment after 13 and 26 weeks and, unexpectedly, did not rise despite substantial weight loss and negative energy balance. This suppression might be of benefit in the maintenance of weight loss but could not be ascribed to the balloon treatment.