Fasting Plasma Ghrelin Levels Increase Progressively after Biliopancreatic Diversion: One-year Follow-up

Background: The role of ghrelin in weight control after surgery is not clear. We examined plasma ghrelin and leptin levels in patients with morbid obesity undergoing biliopancreatic diversion (BPD) of Scopinaro. Methods: 30 adult patients (27 females, 3 males), undergoing elective BPD were recruited from the Hospital Surgery Service. Fasting blood samples for biochemical determinations were drawn before surgery and 1, 3 and 12 months after BPD. Human plasma ghrelin was measured by RIA. Results: During the study period, weight, BMI and serum leptin levels decreased significantly at all sample points compared to preoperative values. Ghrelin plasma levels increased during the study, with statistical significance at 3 months and 1 year after surgery compared with preoperative levels. While leptin changes correlated with changes in BMI, no correlation was found between ghrelin and leptin or BMI changes. Conclusion: Plasma ghrelin levels could be decreased in obese patients as a compensatory mechanism to their nutritional state, but our results do not support the postulated beneficial role of ghrelin in the 1-year weight loss after BPD. They rather suggest that weight loss somehow stimulates ghrelin secretion, even in the absence of part of the stomach.