EnVision CF Multicenter Study of Glucose Tolerance in Cystic Fibrosis

Summary

Cystic Fibrosis Related Diabetes has been identified by the CF community as one of the top ten priorities for CF research. In CF clinical decline due to dysglycemia begins early, prior to diagnosis of diabetes and increases mortality from pulmonary disease. There is presently no way to determine who, of those with dysglycemia, will experience clinical compromise. However, the CF Center in Milan has found that measurable age- and sex-dependent variables on oral glucose tolerance testing (OGTT) predict β-cell failure-the primary driver of decline in CF. the investigators propose a multi-center trial to develop nomograms of age and sex dependent reference values for OGTT-derived measures including glucose, insulin, c-peptide, and the resultant OGTT-derived estimates of β-cell function, β cell sensitivity to glucose, and oral glucose insulin sensitivity (OGIS) and to determine correlation of these with clinical status (FEV-1, BMI z score, number of pulmonary exacerbations over the past 12 months). In a subset of the cohort the investigators will perform additional studies to determine possible mechanisms driving abnormal β cell function, including the role of lean body mass (as measured by DXA), impact of incretin (GLP-1, GIP) and islet hormones (glucagon, pancreatic polypeptide) on β cell function and the relationship of reactive hypoglycemia and catecholamine responses to β cell function, as well as the relationship of β cell sensitivity to glucose as determined by our model to abnormalities in blood glucose found in a period of free living after the study (determined by continuous glucose monitoring measures (Peak glucose, time spent \>200 mg/dl, standard deviation). the investigators will also develop a biobank of stored samples to allow expansion to the full cohort if warranted and to enable future studies of dysglycemia and diabetes in CF. the investigator's eventual goal is utilization of the nomograms to determine the minimum number of measures to accurately predict risk for clinical decline from dysglycemia in CF.

Conditions

• Cystic Fibrosis-related Diabetes

Interventions

DIAGNOSTIC_TEST

Oral glucose tolerance test

oral glucose solution is given by mouth, blood is drawn prior to the administration of the oral glucose beverage and then at timed intervals afterward. This is the standard test to diagnosis cystic fibrosis related diabetes mellitus. However, this study will have more time points than standard screening for cystic fibrosis related diabetes mellitus

DIAGNOSTIC_TEST

Continuous glucose monitoring

a device is placed on the subject's arm that continuously monitors subcutaneous glucose levels for up to 10 days

DIAGNOSTIC_TEST

Dexa scan

low dose x-rays are used to measure the subject's bone density. This is the standard test to diagnose osteoporosis

Sponsors & Collaborators

• Katie Larson Ode

  lead OTHER

Principal Investigators

• Katie Larson Ode, MD · University of Iowa

Study Design

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

DOUBLE

Model

SINGLE_GROUP

Eligibility

Min Age

6 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-07-01

Primary Completion

2023-08-31

Completion

2023-08-31

FDA Device

Yes

Countries

• United States

Study Locations