ECE2018 Poster Presentations: Diabetes, Obesity and Metabolism Obesity (78 abstracts)
Introduction: In vitro and animal studies have suggested that changes in the secretion of ghrelin, PYY, GLP-1, GLP-2 can influence bone metabolism. An increase in osteoblastic differentiation has been observed after the administration of ghrelin and GLP-1. GLP-2 has been associated with a decrease in bone resorption and PYY inversely with markers of bone formation.
Objective: To analyze the association of gastrointestinal hormones with changes in bone mineral density (BMD) and markers of bone resorption after metabolic gastric bypass (mRYGB), Sleeve Gastrectomy (SG) and Greater Curvature Plication (GCP).
Material and methods: Prospective, controlled and randomized study in patients with type 2 diabetes and morbid obesity. Forty-five patients aged 49.4 years, BMI 39.4±1.9 kg/m2, were randomized to mRYGB, SG and GCP. Body composition, BMD and phospho-calcium metabolism, initially and at 12 months were studied. Standard meal test with determination of glucose, insulinemia, GLP-1, GLP-2 and fasting analysis of PYY, ghrelin and glucagon were performed before and at 12 months after surgery.
Results: At 12 months after surgery, the percentage of BMD loss in the lumbar spine (LS) was higher after mRYGB compared to SG and GCP (7.29±4.6 vs. 0.48±3.9 vs. 1, 2±2.7%, P<0.05) with similar findings at the femoral neck. The concentrations of osteocalcin were higher after mRYGB. The secretion of GLP-1 and GLP-2 increased after surgery, but only significantly in mRYGB. Before surgery, PYY and glucagon correlated with CMO (bone mineral content) in LS (r=0.325, P=0.044 and r=0.374, P=0.018). One year after surgery, the AUC for GLP-1 was associated with BMD in LS (r=−0.335, P=0.049) and ghrelin with CMO at that level (r=−0.41, P=0.010). In the regression analysis, the type of surgery was the main determinant of the decrease in BMD but not the hormonal changes.
Conclusions: Changes in gastrointestinal hormones seem to play a role although not relevant in bone metabolism after bariatric surgery.