Continuous Glucose Sensor Profiles in Non-Diabetic Subjects

A Study to Assess Continuous Glucose Sensor Profiles in Healthy Non-Diabetic Subjects

The Juvenile Diabetes Research Foundation (JDRF) Glucose Sensor Study group is carrying out a large, randomized clinical trial to assess the efficacy, safety and cost-effectiveness of use of real-time continuous glucose monitors (RT-CGM) as an adjunct to standard meter plasma glucose testing. Although the primary outcome in the >= 7.0% cohort is differences in HbA1c levels, important secondary outcomes are differences in the percent of glucose sensor values either above or below the target glucose range of 70-180 mg/dl and differences in glucose variability. Prevention of biochemical hypoglycemia is a particularly important outcome in the low HbA1c cohort. Since CGM systems measure interstitial rather than plasma glucose and CGM values differ from simultaneous plasma glucose values by up to 18%, it would be extremely useful for comparative purposes to establish a reference range of sensor values in healthy, non-diabetic control subjects for this study and other future investigations. The objective of this protocol is to establish such reference sensor glucose ranges in each of the 3 devices being utilized in the JDRF study.

Study Overview

• Status: Completed
• Conditions: Healthy Subjects Without Type 1 Diabetes
• Intervention / Treatment: Device: Continuous glucose monitor

Detailed Description

1. After initial eligibility is determined, informed consent and assent are obtained from the parent/guardian and subject.

2. Subjects will have the following tests performed:

   • Hemoglobin A1c (using the DCA2000 or equivalent device)
   • Oral glucose tolerance test to obtain fasting and 2 hour plasma glucose levels

   • Anti-GAD, anti-IA2 and anti-insulin antibodies

     • Subjects with an HbA1c >6.0% and/or fasting glucose levels >100 and/or 2 hour glucose levels >140 will be discontinued from the study.
3. Subjects with normal A1c and glucose levels will be provided with an RT-CGM and home glucose meter (HGM)
4. An RT-CGM sensor will be inserted and initiated by study personnel.
5. Subjects who would like to wear 2 sensors will be given 2 of the same type of RT-CGM.
6. Subjects will be instructed to wear the sensor for 3-7 days (depending on the type of device) and measure the blood glucose on the HGM as needed to calibrate the sensor.

7. Subjects will return to the clinical center after the 3-7 days of sensor wear to return the RT-CGM and HGM.

   • If the subject has less than 48 hours of sensor data he or she will be asked to wear another sensor and return 3-7 days later.

• Study Type: Interventional
• Enrollment (Actual): 74
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • California
    • San Diego, California, United States, 92111
      • Kaiser Permanente
    • Stanford, California, United States, 94305
      • Stanford University
  • Colorado
    • Aurora, Colorado, United States, 80045
      • University of Colorado
  • Connecticut
    • New Haven, Connecticut, United States, 06520
      • Yale University School of Medicine
  • Florida
    • Jacksonville, Florida, United States, 32207
      • Nemours Children's Clinic
  • Georgia
    • Atlanta, Georgia, United States, 30309
      • Atlanta Diabetes Associates
  • Iowa
    • Iowa City, Iowa, United States, 52242
      • Children's Hospital of Iowa
  • Massachusetts
    • Boston, Massachusetts, United States, 02215
      • Joslin Diabetes Center - Adults
    • Boston, Massachusetts, United States, 02215
      • Joslin Diabetes Center - Children
  • Washington
    • Seattle, Washington, United States, 98105
      • University of Washington

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 8 years and older (ADULT, OLDER_ADULT, CHILD)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age > 8 years
• Body mass index (BMI) between the 10th to 90th percentile for age and sex (based on CDC, 2000 nomogram) and < 28 kg body weight/meter in adult subjects
• No significant chronic illness or taking any acute or chronic medications that might affect glucose metabolism.

Exclusion Criteria:

• History of diabetes or positive islet cell antibody testing

Study Plan

How is the study designed?

Design Details

• Allocation: NON_RANDOMIZED
• Interventional Model: SINGLE_GROUP
• Masking: NONE

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Mean Sensor Glucose by Age Group	Mean glucose value was calculated for every hour of the 24 hours of the day. This measure is the average over all 24 hours.	48-72 hours
Daytime (6:00 a.m. - Midnight) Mean Sensor Glucose by Age Group	Mean glucose value was calculated for every hour of the 24 hours of the day. This measure is the average from 6 a.m. to midnight.	48-72 hours
Nighttime (Midnight - 6:00 a.m.) Mean Sensor Glucose by Age Group	Mean glucose value was calculated for every hour of the 24 hours of the day. This measure is the average from midnight to 6 a.m.	48-72 hours
Peak Daytime Sensor Glucose Value by Age Group	The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data.	48-72 hours
Peak Nightime Sensor Glucose Value by Age Group	The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data.	48-72 hours
Daytime Nadir Sensor Glucose Value by Age Group	The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data. The daytime nadir reflects the lowest point on the sensor glucose curve registered among daytime values.	48-72 hours
Nighttime Nadir Sensor Glucose Value by Age Group	The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data. The nighttime nadir reflects the lowest point on the sensor glucose curve registered among nighttime values.	48-72 hours
Percentage of Sensor Glucose Levels Between 71-120 mg/dL by Age Group	The Percentage Sensor Glucose Levels between 71-120 mg/dL was calculated for each subject. The median and quartiles over all subjects were reported here.	48-72 hours
Percentage of Sensor Glucose Levels 71-120 mg/dL by Time of Day		48-72 hours
Distribution of Sensor Glucose Levels <=70 mg/dL by Age Group		48-72 hours
Percentage of Sensor Glucose Levels <=70 mg/dl by Time of Day		48-72 hours
Percentage of Sensor Glucose Levels <=60 mg/dL by Age Group		48-72 hours
Percentage of Sensor Glucose Levels <=60 mg/dl by Time of Day	The Percentage of Sensor Glucose Levels <=60 mg/dl was calculated for each subject separately for the daytime and nighttime period. The median and quartiles over all subjects were reported. Here the data is different with data analyzed by age group, which is a subgroup analysis on 'percentage of sensor glucose levels <=60mg/dL' for all 24 hours.	48-72 hours
Percentage of Sensor Glucose Levels >120 mg/dL by Age Group		48-72 hours
Percentage of Sensor Glucose Levels >120 mg/dl by Time of Day		48-72 hours
Percentage of Sensor Glucose Levels >140 mg/dL by Age Group		48-72 hours
Percentage of Sensor Glucose Levels >140 mg/dl by Time of Day	The Percentage of Sensor Glucose Levels >140 mg/dl was calculated for each subject separately for the daytime and nighttime period. The median and quartiles over all subjects were reported. Here the data is different with data analyzed by age group, which is a subgroup analysis on 'percentage of sensor glucose levels >140 mg/dl' for all 24 hours.	48-72 hours
Glucose Variability Measure- Standard Deviation by Age Group	Here, 'Standard Deviation' is a measure of glucose variability. This measure was calculated by taking the SD of all glucose values for each subject. Each subject has a SD value. The median and quartiles of this measure over all subjects were reported.	48-72 hours
Glucose Variability Measure- Standard Deviation by Time of Day	Here, 'Standard Deviation' is a measure of glucose variability. This measure was calculated by taking the SD of all glucose values for each subject. Each subject has a SD value. The median and quartiles of this measure over all subjects were reported.	48-72 hours
Glucose Variability Measure- Absolute Rate of Change by Age Group		48-72 hours
Glucose Variability Measure- Absolute Rate of Change by Time of Day		48-72 hours
Glucose Variability Measure- Coefficient of Variation by Age Group	The Coefficient of Variation is calculated by dividing the standard deviation by the mean glucose. Each subject received a SD value. The median and quartiles of this measure over all subjects were reported.	48-72 hours
Glucose Variability Measure- Coefficient of Variation by Time of Day	The Coefficient of Variation is calculated by dividing the standard deviation by the mean glucose. Each subject received a SD value. The median and quartiles of this measure over all subjects were reported.	48-72 hours
Glucose Variability Measure: Mean Amplitude of Glycemic Excursions by Age Group	The Mean Amplitude of Glycemic Excursions also known as MAGE depicts the upward and downward acute glucose fluctuations seen in the sensor data.	48-72 hours
Glucose Variability Measure: Amplitude of Glycemic Excursions by Time of Day	The Mean Amplitude of Glycemic Excursions also known as MAGE depicts the upward and downward acute glucose fluctuations seen in the sensor data.	48-72 hours

Collaborators and Investigators

• Sponsor: Jaeb Center for Health Research
• Collaborators: JDRF Artificial Pancreas Project
• Investigators: Study Chair: Lori Laffel, M.D., Joslin Diabetes Center Pediatric Section; Study Chair: William Tamborlane, M.D., Yale University

Publications and helpful links

General Publications

• Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Study Group; Fox LA, Beck RW, Xing D. Variation of interstitial glucose measurements assessed by continuous glucose monitors in healthy, nondiabetic individuals. Diabetes Care. 2010 Jun;33(6):1297-9. doi: 10.2337/dc09-1971. Epub 2010 Mar 9.

Study record dates

Study Major Dates

• Study Start: July 1, 2008
• Primary Completion (ACTUAL): December 1, 2008
• Study Completion (ACTUAL): March 1, 2009

Study Registration Dates

• First Submitted: July 16, 2008
• First Submitted That Met QC Criteria: July 16, 2008
• First Posted (ESTIMATE): July 18, 2008

Study Record Updates

• Last Update Posted (ESTIMATE): October 19, 2016
• Last Update Submitted That Met QC Criteria: September 2, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Immune System Diseases; Autoimmune Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1
• Other Study ID Numbers: 2008-2403