Continuous Glucose Sensor Profiles in Non-Diabetic Subjects

• ClinicalTrials.gov Identifier: NCT00717977
• Recruitment Status: Completed
• First Posted: July 18, 2008
• Results First Posted: October 18, 2010
• Last Update Posted: October 19, 2016
• Sponsor: Jaeb Center for Health Research
• Collaborator: JDRF Artificial Pancreas Project
• Information provided by (Responsible Party): Jaeb Center for Health Research

Study Description

Brief Summary:

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.

Condition or disease	Intervention/treatment	Phase
Healthy Subjects Without Type 1 Diabetes	Device: Continuous glucose monitor	Phase 4

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 Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 74 participants
• Allocation: Non-Randomized
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Official Title: A Study to Assess Continuous Glucose Sensor Profiles in Healthy Non-Diabetic Subjects
• Study Start Date: July 2008
• Actual Primary Completion Date: December 2008
• Actual Study Completion Date: March 2009

Arms and Interventions

Intervention Details:

• Device: Continuous glucose monitor
  Daily use of a continuous glucose monitor for 3-7 days
  Other Names:

  • Abbott FreeStyle Navigator
  • DexCom SEVEN
  • Medtronic Guardian Clinical

Outcome Measures

Primary Outcome Measures :

1. Overall Mean Sensor Glucose by Age Group [ Time Frame: 48-72 hours ]
   Mean glucose value was calculated for every hour of the 24 hours of the day. This measure is the average over all 24 hours.
2. Daytime (6:00 a.m. - Midnight) Mean Sensor Glucose by Age Group [ Time Frame: 48-72 hours ]
   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.
3. Nighttime (Midnight - 6:00 a.m.) Mean Sensor Glucose by Age Group [ Time Frame: 48-72 hours ]
   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.
4. Peak Daytime Sensor Glucose Value by Age Group [ Time Frame: 48-72 hours ]
   The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data.
5. Peak Nightime Sensor Glucose Value by Age Group [ Time Frame: 48-72 hours ]
   The calculation of peak and nadir glucose was restricted to days with >=12 hours and nights with >=4 hours of sensor glucose data.
6. Daytime Nadir Sensor Glucose Value by Age Group [ Time Frame: 48-72 hours ]
   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.
7. Nighttime Nadir Sensor Glucose Value by Age Group [ Time Frame: 48-72 hours ]
   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.
8. Percentage of Sensor Glucose Levels Between 71-120 mg/dL by Age Group [ Time Frame: 48-72 hours ]
   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.
9. Percentage of Sensor Glucose Levels 71-120 mg/dL by Time of Day [ Time Frame: 48-72 hours ]
10. Distribution of Sensor Glucose Levels <=70 mg/dL by Age Group [ Time Frame: 48-72 hours ]
11. Percentage of Sensor Glucose Levels <=70 mg/dl by Time of Day [ Time Frame: 48-72 hours ]
12. Percentage of Sensor Glucose Levels <=60 mg/dL by Age Group [ Time Frame: 48-72 hours ]
13. Percentage of Sensor Glucose Levels <=60 mg/dl by Time of Day [ Time Frame: 48-72 hours ]

    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.

14. Percentage of Sensor Glucose Levels >120 mg/dL by Age Group [ Time Frame: 48-72 hours ]
15. Percentage of Sensor Glucose Levels >120 mg/dl by Time of Day [ Time Frame: 48-72 hours ]
16. Percentage of Sensor Glucose Levels >140 mg/dL by Age Group [ Time Frame: 48-72 hours ]
17. Percentage of Sensor Glucose Levels >140 mg/dl by Time of Day [ Time Frame: 48-72 hours ]

    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.

18. Glucose Variability Measure- Standard Deviation by Age Group [ Time Frame: 48-72 hours ]
    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.
19. Glucose Variability Measure- Standard Deviation by Time of Day [ Time Frame: 48-72 hours ]
    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.
20. Glucose Variability Measure- Absolute Rate of Change by Age Group [ Time Frame: 48-72 hours ]
21. Glucose Variability Measure- Absolute Rate of Change by Time of Day [ Time Frame: 48-72 hours ]
22. Glucose Variability Measure- Coefficient of Variation by Age Group [ Time Frame: 48-72 hours ]
    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.
23. Glucose Variability Measure- Coefficient of Variation by Time of Day [ Time Frame: 48-72 hours ]
    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.
24. Glucose Variability Measure: Mean Amplitude of Glycemic Excursions by Age Group [ Time Frame: 48-72 hours ]
    The Mean Amplitude of Glycemic Excursions also known as MAGE depicts the upward and downward acute glucose fluctuations seen in the sensor data.
25. Glucose Variability Measure: Amplitude of Glycemic Excursions by Time of Day [ Time Frame: 48-72 hours ]
    The Mean Amplitude of Glycemic Excursions also known as MAGE depicts the upward and downward acute glucose fluctuations seen in the sensor data.

Eligibility Criteria

• Ages Eligible for Study: 8 Years and older (Child, Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

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

Contacts and Locations

Locations

United States, California

Kaiser Permanente

San Diego, California, United States, 92111

Stanford University

Stanford, California, United States, 94305

United States, Colorado

University of Colorado

Aurora, Colorado, United States, 80045

United States, Connecticut

Yale University School of Medicine

New Haven, Connecticut, United States, 06520

United States, Florida

Nemours Children's Clinic

Jacksonville, Florida, United States, 32207

United States, Georgia

Atlanta Diabetes Associates

Atlanta, Georgia, United States, 30309

United States, Iowa

Children's Hospital of Iowa

Iowa City, Iowa, United States, 52242

United States, Massachusetts

Joslin Diabetes Center - Adults

Boston, Massachusetts, United States, 02215

Joslin Diabetes Center - Children

Boston, Massachusetts, United States, 02215

United States, Washington

University of Washington

Seattle, Washington, United States, 98105

Sponsors and Collaborators

Jaeb Center for Health Research

JDRF Artificial Pancreas Project

Investigators

• Study Director: Roy W Beck, M.D., Ph.D.; Jaeb Center for Health Research
• Study Chair: Lori Laffel, M.D.; Joslin Diabetes Center Pediatric Section
• Study Chair: William Tamborlane, M.D.; Yale University

More Information

Publications of Results:

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.

• Responsible Party: Jaeb Center for Health Research
• ClinicalTrials.gov Identifier: NCT00717977
• Other Study ID Numbers: 2008-2403
• First Posted: July 18, 2008
• Results First Posted: October 18, 2010
• Last Update Posted: October 19, 2016
• Last Verified: September 2016

Additional relevant MeSH terms:

Diabetes Mellitus, Type 1; Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases