title: No Islet Cell Hyperfunction, but Altered Gut-Islet Regulation and Postprandial Hypoglycemia in Glucose-Tolerant Patients 3 Years After Gastric Bypass Surgery.
abstract: Postprandial hyperinsulinemia characterizes Roux-en-Y gastric bypass (RYGB) and sometimes leads to reactive hypoglycemia. We prospectively evaluated changes in beta cell function in seven RYGB-operated patients with a median follow-up of 2.9 years with hyperglycemic clamps and oral glucose tolerance tests (OGTTs). Three years after RYGB, weight loss was 26 % and insulin sensitivity had improved. Insulin secretion during clamp experiments was largely unchanged compared to before surgery. In contrast, insulin secretion in response to the OGTTs doubled when evaluated by the disposition index and 2-h plasma glucose declined to a mean of 3.3 ± 0.3 mmol/l postoperatively. Our findings indicate that intrinsic beta cell function remains unchanged in glucose-tolerant patients even years after RYGB, while altered gut-islet regulation drive risk of postprandial hyperinsulinemic hypoglycemia.
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark. cardir@gmail.com.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark. cardir@gmail.com.
authors.forename: Carsten
authors.initials: C
authors.lastname: Dirksen
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Eiken
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Kirstine N
authors.initials: KN
authors.lastname: Bojsen-Møller
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Maria S
authors.initials: MS
authors.lastname: Svane
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Christoffer
authors.initials: C
authors.lastname: Martinussen
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.|NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Nils B
authors.initials: NB
authors.lastname: Jørgensen
authors.affiliation: NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.|Department of Biomedical Sciences, The Panum Institute, University of Copenhagen, DK-2200, Copenhagen N, Denmark.
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Holst
authors.affiliation: Department of Endocrinology, Hvidovre Hospital, Kettegaard Allé 30, DK-2650, Hvidovre, Denmark.
authors.forename: Sten
authors.initials: S
authors.lastname: Madsbad
mesh_terms: D001786:Blood Glucose; D015390:Gastric Bypass / Q000706:statistics & numerical data*; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology*; D007515:Islets of Langerhans / Q000503:physiopathology*; D009767:Obesity, Morbid / Q000601:surgery; D019518:Postprandial Period; D011446:Prospective Studies
chemical_list: D001786:Blood Glucose
keywords: Bariatric surgery; Glucagon; Glucagon-like peptide-1; Glucose-dependent insulinotropic polypeptide; Insulin resistance; Insulin secretion rate; Obesity