Itariu Bianca K, Zeyda Maximilian, Prager Gerhard, Stulnig Thomas M
Division of Endocrinology and Metabolism, Department of Medicine III, Medical University Vienna, Vienna, Austria; Christian Doppler Laboratory for Cardio-Metabolic Immunotherapy, Medical University Vienna, Vienna, Austria.
Department of Surgery, Medical University of Vienna, Vienna, Austria.
PLoS One. 2014 Apr 15;9(4):e94613. doi: 10.1371/journal.pone.0094613. eCollection 2014.
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.
餐后低血糖是胃旁路手术后的一种并发症，常常未被发现。然而，严重的低血糖发作会使患者面临风险，例如晕厥。胃旁路术后低血糖的一个主要原因是高胰岛素血症性胰岛细胞增殖症。由于胰岛细胞增殖症中的胰岛过度表达胰岛素样生长因子1（IGF-1）受体α，且给予重组IGF-1会引发低血糖，我们的主要目的是研究减肥手术后一年负荷后低血糖的发生情况及其与术前和术后IGF-1血清浓度的关系。我们评估了包括2小时75克口服葡萄糖耐量试验（OGTT）在内的代谢参数，并测量了36例非糖尿病患者（29名女性/7名男性）的IGF-1血清浓度，这些患者年龄为41.3±2.0岁，体重指数（BMI）中位数（四分位间距）为30.9 kg/m²（27.5 - 34.3 kg/m²），在我院接受了择期减肥手术（主要是胃旁路手术，占83%）。50%的患者检测到负荷后低血糖，定义为2小时血糖浓度<60 mg/dl。低血糖患者和血糖正常患者在OGTT期间的血清胰岛素和C肽浓度以及稳态模型评估胰岛素抵抗（HOMA-IR）相似。令人惊讶的是，低血糖患者术前和术后的血清IGF-1浓度显著更高（分别为p = 0.012和p = 0.007）。术前IGF-1血清浓度与OGTT期间2小时血糖浓度呈负相关（rho = -0.58，p = 0.0003）。最后，术前和术后IGF-1血清浓度显著预测负荷后低血糖，每增加10 ng/ml，比值比分别为1.28（95%置信区间：1.03 - 1.55，p = 0.029）和1.18（95%置信区间：1.03 - 1.33，p = 0.015）。IGF-1血清浓度可能是一种有价值的生物标志物，可独立于诊断性OGTT识别减肥手术后有低血糖风险的患者。因此，IGF-1检测有助于预防胃旁路手术的一种严重并发症。
