Fasting ghrelin levels after gastric bypass and vertical sleeve gastrectomy: An analytic cohort study.

Background And Objective: Neuronal populations involved in the regulation of food intake, particularly the orexigenic (appetite-stimulating) hormone ghrelin, are found in the hypothalamus. Changes in plasma ghrelin levels have been observed following different bariatric surgery procedures, but the results from different studies are contradictory. Much remains unknown regarding the role of ghrelin in the weight loss process following bariatric surgery. Our objective was to describe the behaviour of fasting ghrelin levels, comparing the changes occurring between 2 different surgical techniques (gastric bypass versus vertical sleeve gastrectomy) and their correlation with weight loss.

Patients And Method: A prospective, observational, analytic cohort study of 54 patients (27 for each surgical technique) with a 12-month follow-up period. We analysed demographic data, anthropometric data, comorbidities, weight loss and evolution of fasting ghrelin.

Results: The behaviour of acylated ghrelin was similar with the 2 surgical techniques, with no significant differences between gastric bypass and vertical sleeve gastrectomy. With both procedures, there was an increase in acylated ghrelin on day 5 and a subsequent decrease, and levels then gradually increased to reach values at 12 months that were higher than those reported preoperatively. This increase in ghrelin levels did not affect weight loss, since one year post-surgery, 30% weight loss was achieved with both types of surgery.

Conclusions: We observed an increase in fasting acylated ghrelin levels at one year of follow-up with both surgical techniques, with 30% weight loss.