Persistence of Individual Variations in Glycated Hemoglobin
Analysis of data from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Randomized Trial
- Darrell M. Wilson, MD1,
- Dongyuan Xing, MPH2,
- Jing Cheng, MS2,
- Roy W. Beck, MD, PHD2⇓,
- Irl Hirsch, MD3,
- Craig Kollman, PHD2,
- Lori Laffel, MD, MPH4,
- Jean M. Lawrence, SCD, MPH, MSSA5,
- Nelly Mauras, MD6,
- Katrina J. Ruedy, MSPH2,
- Eva Tsalikian, MD7,
- Howard Wolpert, MD8 and
- for the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Study Group*
- 1Division of Pediatric Endocrinology and Diabetes, Stanford University, Stanford, California
- 2Jaeb Center for Health Research, Tampa, Florida
- 3Diabetes Care Center, University of Washington, Seattle, Washington
- 4Pediatric, Adolescent, and Young Adult Section, Joslin Diabetes Center, Boston, Massachusetts
- 5Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, California
- 6Division of Endocrinology and Metabolism, Nemours Children’s Clinic, Jacksonville, Florida
- 7Department of Pediatrics, University of Iowa Carver College of Medicine, Iowa City, Iowa
- 8Adult Section, Joslin Diabetes Center, Boston, Massachusetts
- ↵Corresponding author: Roy W. Beck, .
OBJECTIVE To determine the individual persistence of the relationship between mean sensor glucose (MG) concentrations and hemoglobin A1c (A1C) from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring (CGM) Randomized Trial.
RESEARCH DESIGN AND METHODS MG was calculated using CGM data for 3 months before A1C measurements at 3, 6, 9, and 12 months for the CGM group and at 9 and 12 months for the control group. An MG-to-A1C ratio was included in analysis for subjects who averaged ≥4 days/week of CGM use.
RESULTS Spearman correlations of the MG-to-A1C ratio between consecutive visits 3 months apart ranged from 0.70 to 0.79. The correlations for children and youth were slightly smaller than those for adults. No meaningful differences were observed by device type or change in A1C.
CONCLUSIONS Individual variations in the rate of hemoglobin glycation are persistent and contribute to the inaccuracy in estimating MGs calculated from A1C levels.
- Received August 31, 2010.
- Accepted March 10, 2011.
- © 2011 by the American Diabetes Association.
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details.