Characterization of patients with cystic fibrosis presenting an indeterminate glucose tolerance (INDET)

Background: CFRD is preceded and associated with a significantly increased morbidity and mortality. We aimed to characterize a large newly established glucose tolerance subgroup named INDET (indeterminate; 1-h oral glucose tolerance test (OGTT) > 11.0 but 2 h-OGTT < 7.8 mmol/L) in adult patients with cystic fibrosis (CF). Methods: All CF participants (n = 252, >= 18 yrs without CFRD) underwent a 2 h-OGTT with glucose and insulin sample measurements every 30 min. They were then classified as having either normal, impaired, or INDET glucose tolerance, or de novo CFRD. Other clinical characteristics were collected such as the BMI and pulmonary function. Results: All groups were of similar age (P = 0.629) and BMI (P = 0.813). We found that the INDETs displayed decreased lung function comparable to de novo CFRD. OGTT-derived glucose or insulin secretion/sensitivity parameters cannot fully explain this observation. Conclusions: Prospective studies are required to establish if the INDET-CF group can identify clinically relevant outcomes. (C) 2015 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.