Insulin-like growth factor 1 predicts post-load hypoglycemia following bariatric surgery: a prospective cohort study

• Published in: PloS one Vol. 9; no. 4; p. e94613
• Main Authors: Itariu, Bianca K, Zeyda, Maximilian, Prager, Gerhard, Stulnig, Thomas M
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.04.2014; Public Library of Science (PLoS)
• Subjects: Adult; Bariatric Surgery - adverse effects; Bioindicators; Biology and Life Sciences; Biomarkers; Biomarkers - blood; Body mass; Body measurements; Bypasses; Cohort analysis; Cohort Studies; Diabetes; Diabetes mellitus; Diagnosis; Diagnostic systems; Endocrinology; Female; Gastric bypass; Gastroenterology; Gastrointestinal surgery; Glucose; Glucose tolerance; Glucose Tolerance Test; Humans; Hypoglycemia; Hypoglycemia - blood; Hypoglycemia - etiology; Immunotherapy; Insulin; Insulin resistance; Insulin-like growth factor 1; Insulin-like growth factor I; Insulin-Like Growth Factor I - metabolism; Insulin-like growth factors; Laboratories; Liver; Longitudinal Studies; Male; Medicine; Medicine and Health Sciences; Metabolism; Metabolites; Mortality; Obesity; Pancreas; Patients; Physiological aspects; Prospective Studies; Risk; Risk factors; Surgery; Syncope; Weight control; Austria
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0094613

Postprandial hypoglycemia is a complication following gastric bypass surgery, which frequently remains undetected. Severe hypoglycemic episodes, however, put patients at risk, e.g., for syncope. A major cause of hypoglycemia following gastric bypass is hyperinsulinemic nesidioblastosis. Since pancreatic islets in nesidioblastosis overexpress insulin-like growth factor 1 (IGF-1) receptor α and administration of recombinant IGF-1 provokes hypoglycemia, our main objective was to investigate the occurrence of post-load hypoglycemia one year after bariatric surgery and its relation to pre- and post-operative IGF-1 serum concentrations. We evaluated metabolic parameters including 2 h 75 g oral glucose tolerance test (OGTT) and measured IGF-1 serum concentration in thirty-six non-diabetic patients (29 f/7 m), aged 41.3±2.0 y with a median (IQR) BMI of 30.9 kg/m2 (27.5-34.3 kg/m2), who underwent elective bariatric surgery (predominantly gastric bypass, 83%) at our hospital. Post-load hypoglycemia as defined by a 2 h glucose concentration <60 mg/dl was detected in 50% of patients. Serum insulin and C-peptide concentration during the OGTT and HOMA-IR (homeostatic model assessment-insulin resistance) were similar in hypoglycemic and euglycemic patients. Strikingly, pre- and post-operative serum IGF-1 concentrations were significantly higher in hypoglycemic patients (p = 0.012 and p = 0.007 respectively). IGF-1 serum concentration before surgery negatively correlated with 2 h glucose concentration during the OGTT (rho = -0.58, p = 0.0003). Finally, IGF-1 serum concentrations before and after surgery significantly predicted post-load hypoglycemia with odds ratios of 1.28 (95%CI:1.03-1.55, p = 0.029) and 1.18 (95%CI:1.03-1.33, p = 0.015), respectively, for each 10 ng/ml increment. IGF-1 serum concentration could be a valuable biomarker to identify patients at risk for hypoglycemia following bariatric surgery independently of a diagnostic OGTT. Thus, IGF-1 testing could help to prevent a significant complication of gastric bypass surgery.