Clinical trial NCT02211235: Glycemic Monitoring in Cystic Fibrosis
Official title: Characterization of Glucose Variability by Continuous Glucose Monitoring in Non-diabetic Youth With and Without Cystic Fibrosis
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Cystic Fibrosis
Keywords: Cystic Fibrosis
Healthy Controls
Diabetes
Cystic Fibrosis Related Diabetes (CFRD)
CFRD
Lead sponsor: University of Colorado, Denver
Sponsor class: OTHER
First posted: 2014-08-07
Enrollment: 146
Sex: ALL
Minimum age (years): 6
Maximum age (years): 25
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Children and Adolescents ages 6-25, without diabetes. Out of 160 people, 45 will be healthy controls, 45 with Cystic Fibrosis (normal glucose tolerance), and 70 with Cystic Fibrosis-related diabetes or pre-diabetes.

Brief summary: Current guidelines on the diagnoses and management of cystic fibrosis (CF) related diabetes recommend treatment for diabetes based on diagnostic criteria derived from adults with type 2 diabetes. Increasing evidence supports treating early glucose abnormalities in cystic fibrosis patients to target CF specific outcomes, including lung function and nutrition (BMI-Body Mass Index). However, the criteria and timing of when to start insulin therapy in the 'prediabetic' state are unclear. A more accurate characterization of blood sugar variability in youth with and without CF will help the investigators better interpret continuous glucose monitor (CGM) findings in patients with CF prediabetes and diabetes and more accurately identify those individuals at greatest risk for disease progression.


Eligibility criteria: Inclusion Criteria:

Healthy controls (n=45) -

1. Age 10-25 years
2. BMI \<85th percentile
3. Baseline health at enrollment

CF controls (n=45) -

1. Age 10-25 years
2. Diagnosis of cystic fibrosis (by newborn screen, sweat chloride testing, or genetic testing)
3. Baseline health at enrollment (no inclusion/exclusion criteria for CF patients based on lung function, BMI, pancreatic insufficiency, or genotype)

CF prediabetes \& CFRD (n=70)

1. Age 10-25 years
2. Diagnosis of cystic fibrosis (by newborn screen, sweat chloride testing, or genetic testing)
3. History of abnormal oral glucose tolerance testing (2h-glucose \>140, fasting plasma glucose \>100,1hr glucose \>200)
4. If taking medication that affects glucose metabolism (ex. Insulin, insulin sensitizers, glucocorticoids, atypical antipsychotics), should be on a stable dose over the past 3 months

Exclusion Criteria:

Healthy controls -

1. Known diagnosis of diabetes or prediabetes (including type 1, type 2, MODY), abnormal oral glucose tolerance test (OGTT) (ie. fasting plasma glucose ≥100 or 2hr ≥140 mg/dl) or HbA1c ≥ 5.7%
2. BMI ≥85th percentile
3. Chronic disease that may affect glucose metabolism or use of medications affecting glucose metabolism in the past 3 months (ex. Insulin, insulin sensitizers, glucocorticoids, atypical antipsychotics)
4. Presence of type 1 diabetes auto-antibodies in any individuals with a first degree relative with type 1 diabetes (will only include first degree relatives if they have had previous negative auto-antibody screening performed as part of participation in other studies such as the Trial Net studies at the Barbara Davis Center)
5. Acute illness (ex. Asthma exacerbation, gastroenteritis, febrile illness)
6. Pregnancy

CF participants -

1. Diagnosis of type 1 diabetes, type 2 diabetes, or MODY
2. Varying doses of medication affecting glucose metabolism in the past 3 months
3. Pulmonary exacerbation associated with hospitalization, or systemic steroid requirement in the preceding 6 weeks
4. Pregnancy

Primary outcomes:
measure: The percentage of time spent > 140 mg/dl on CGM
timeFrame: 7 days
Secondary outcomes:
measure: The percentage of time spent > 120 mg/dl on CGM
timeFrame: 7 days
measure: The percentage of time spent > 200 mg/dl on CGM
timeFrame: 7 days
measure: The percentage of time spent < 70 mg/dl on CGM
timeFrame: 7 days
measure: The percentage of time spent < 60 mg/dl on CGM
timeFrame: 7 days
measure: The number of excursions > 200mg/dl in 24 hours for one week
timeFrame: 7 days
Other outcomes:
measure: Change in CGM variables and BMI
timeFrame: 3 years
measure: Change in CGM variables and lung function
timeFrame: 3 years
measure: Characterize the relationships between markers of glycemia
timeFrame: 3 days
Locations:
city: Aurora
country: United States
facility: Children's Hospital Colorado, University of Colorado Denver
state: Colorado
Study officials:
affiliation: University of Colorado, Denver
name: Christine L Chan, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Chan CL, Pyle L, Vigers T, Zeitler PS, Nadeau KJ. The Relationship Between Continuous Glucose Monitoring and OGTT in Youth and Young Adults With Cystic Fibrosis. J Clin Endocrinol Metab. 2022 Jan 18;107(2):e548-e560. doi: 10.1210/clinem/dgab692.
citation: Tommerdahl KL, Brinton JT, Vigers T, Cree-Green M, Zeitler PS, Nadeau KJ, Chan CL. Delayed glucose peak and elevated 1-hour glucose on the oral glucose tolerance test identify youth with cystic fibrosis with lower oral disposition index. J Cyst Fibros. 2021 Mar;20(2):339-345. doi: 10.1016/j.jcf.2020.08.020. Epub 2020 Sep 11.
citation: Chan CL, Hope E, Thurston J, Vigers T, Pyle L, Zeitler PS, Nadeau KJ. Hemoglobin A1c Accurately Predicts Continuous Glucose Monitoring-Derived Average Glucose in Youth and Young Adults With Cystic Fibrosis. Diabetes Care. 2018 Jul;41(7):1406-1413. doi: 10.2337/dc17-2419. Epub 2018 Apr 19.