376-OR: Chronic Pancreatitis Does Not Induce Specific Alterations in Beta-Cell Function

Abstract

Chronic pancreatitis (CP) is the most frequent cause of diabetes due to pancreatic diseases, known as type 3c diabetes mellitus (T3cDM). Although the specific alterations of T3cDM are not completely understood, individuals with T3cDM are considered affected by pancreatic endocrine insufficiency and often treated with insulin. To investigate the functional alterations of T3cDM, we evaluated differences in beta-cell function in patients with and without CP, classified according to their glucose tolerance (NGT, IGT, DM). We recruited 50 patients with CP and 96 individuals without CP (NCP). All participants underwent OGTT, hyperglycemic clamp (HC), hyperinsulinemic euglycemic clamp and mixed meal test (MMT) with measurement of GLP-1 and glucagon. Basal insulin secretion rate (ISR), total ISR, rate secretion and β-cell glucose sensitivity (RS and GS) were estimated by mathematical models from OGTT, MMT and HC. Comparing individuals classified into NGT, IGT or DM based on OGTT-derived glucose tolerance, we did not find any difference in beta-cell function derived by OGTT and MMT within the same category (e.g.: NGT-CP vs. NGT-NCP). GLP-1 and glucagon secretion during MMT was not significantly different between CP vs. NCP. Of note, we found that insulin secretion after arginine stimulus in HC, an indirect measure of beta-cell mass, was reduced only in DM-CP vs. DM-NCP (ARG CP 397 (132; 662) pmol/l vs NCP 795 (604; 1134) pmol/l; p= 0.023). No difference was found in insulin sensitivity evaluated as glucose uptake during euglycemic clamp. At equivalent levels of glucose tolerance, patients with CP had similar beta-cell function, GLP-1 and glucagon secretion to individuals without CP. People with T3cDM have less beta-cell mass than patients with DM without CP, but analogous residual beta-cell function, so they could benefit from other therapies apart from insulin. Future studies are warranted to investigate differences in beta-cell function decline between type 2 diabetes mellitus and T3cDM. Disclosure G.Ciccarelli: None. G.Di giuseppe: None. F.Cinti: None. A.Mari: Consultant; Eli Lilly and Company. T.Mezza: None. A.Giaccari: Speaker's Bureau; Abbott, AstraZeneca, Boehringer-Ingelheim, Eli Lilly and Company, Merck Sharp & Dohme Corp., Novo Nordisk, Sanofi.