Meal-induced PYY and GLP1 secretions differently predict long-term weight loss after sleeve gastrectomy

Gut hormones such as GLP-1 and PYY increase after bariatric surgery. However, implication of endogenous gut hormones in weight loss (WL) after surgery remains unclear. Our study aimed at objectifying the role of gut hormones in postoperative WL in 32 women with obesity who underwent vertical sleeve gastrectomy (VSG).

Post-meal tests were realized to measure plasma gut hormones (GLP-1, PYY and ghrelin), before and 6 months after VSG. Area under the curve and peak/basis ratios (T30/T0) were analyzed for each hormone in relation to percentage WL (%WL) and caloric intake decrease (%CID) evaluated at 6, 12, 36 months after surgery.

Fasting GLP-1 and PYY secretions were not altered by surgery but their postprandial peaks were significantly elevated. Fasting and postprandial Ghrelin secretions were drastically reduced. Preoperative ghrelin was negatively correlated with 6 months %CID. Preoperative peak/basis ratio of PYY and GLP-1 were both negatively correlated with postoperative %WL at 36 months (P < 0,01 and P < 0,05). Post/preoperative peak ratios of PYY secretion were positively correlated to %WL from 6 months to 36 months after VSG (P < 0,05). Finally, receiver operating characteristic (ROC) curve analyses show that preoperative peak/basis PYY or GLP-1 and post/preoperative peak ratios of PYY were able to predict long-term efficiency of VSG defined as %WL ≥ 30 % at 36 months.

Preoperative postprandial secretion of PYY and its ability to increase early after surgery is predictive of long-term WL after VSG. This study emphasizes the importance of postprandial gut hormone assessment to improve the operated patient's personalized care.