Glucose Metabolism in the Immediate and Short Term Follow up After Bariatric Surgery

Subjects undergo a standard mixed meal tolerance test \& hyperglycemic clamp to assess insulin secretion \& sensitivity (whole body glucose disposal) pre-op. Following surgery, at 1week, 1 month, 6 months and 12 months subjects will undergo hyperglycemic clamp \& mixed meal tolerance test. During these tests, measurements will include plasma levels of glucose, insulin, C-peptide, free fatty acid levels and adipocyte hormone profile (adiponectin, leptin, resistin). A gut hormone profile (ghrelin, glucagons-like-peptide 1 GLP-1, glucose-dependent insulinotropic polypeptide GIP, PYY) will be performed at fasting \& specific postprandial times. Results will be compared between two groups: patients undergoing laparoscopic Roux-en-Y gastric bypass \& gastric banding.