ABSTRACT
BACKGROUND: The mechanisms of amelioration of glycemic control early after laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) are not fully understood. METHODS: In this prospective, randomized 1-year trial, outcomes of LRYGB and LSG patients were compared, focusing on possibly responsible mechanisms. Twelve patients were randomized to LRYGB and 11 to LSG. These non-diabetic patients were investigated before and 1 week, 3 months, and 12 months after surgery. A standard test meal was given after an overnight fast, and blood samples were collected before, during, and after food intake for hormone profiles (cholecystokinin (CCK), ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY)). RESULTS: In both groups, body weight and BMI decreased markedly and comparably leading to an identical improvement of abnormal glycemic control (HOMA index). Post-surgery, patients had markedly increased postprandial plasma GLP-1 and PYY levels (p < 0.05) with ensuing improvement in glucose homeostasis. At 12 months, LRYGB ghrelin levels approached preoperative values. The postprandial, physiologic fluctuation returned, however, while LSG ghrelin levels were still markedly attenuated. One year postoperatively, CCK concentrations after test meals increased less in the LRYGB group than they did in the LSG group, with the latter showing significantly higher maximal CCK concentrations (p < 0.012 vs. LRYGB). CONCLUSIONS: Bypassing the foregut is not the only mechanism responsible for improved glucose homeostasis. The balance between foregut (ghrelin, CCK) and hindgut (GLP-1, PYY) hormones is a key to understanding the underlying mechanisms.
Subject(s)
Blood Glucose/metabolism , Gastric Bypass , Gastrointestinal Hormones/blood , Gastroplasty , Glycated Hemoglobin/metabolism , Laparoscopy , Obesity, Morbid/blood , Adult , Cholecystokinin/blood , Female , Ghrelin/blood , Glucagon-Like Peptide 1/blood , Humans , Male , Obesity, Morbid/surgery , Peptide YY/blood , Postprandial Period , Prospective Studies , Weight LossABSTRACT
BACKGROUND: Constipation is an occasional problem after gastric banding and is often caused by insufficient liquid intake. As a result, the use of laxatives is widespread in such patients. Depending on the laxative, improper use can lead to bolus obstruction above the band, as occurred in this case. CASE REPORT: A 59-year-old female with uncomplicated laparoscopic adjustable gastric banding presented 2 months after surgery with food and liquid intolerance and dysphagia after ingestion of a granular bulking laxative. Despite deflating the band, the bolus could not be washed out. Endoscopic extraction was required, revealing a 4x2 cm bolus of the laxative and a small compression ulcer. DISCUSSION: Patients not complying with nutritional recommendations after gastric banding may have insufficient liquid intake and, consequently, constipation. Under these conditions, the use of a granular bulking laxative entails the risk of esophageal obstruction above the band. CONCLUSION: Nutritional counseling after gastric banding should include the recommendation of liquid intake of at least 1.5 l/day. If constipation occurs, osmotic or paraffin oil laxatives should be used instead of bulking laxatives.
