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Evaluation of Hemoglobin A1c before and after initiation of continuous glucose monitoring in children with type 1 diabetes mellitus

Shilpa Gurnurkar EMAIL logo , Lindsey Owens , Sweta Chalise and Neha Vyas



The development of continuous glucose monitoring (CGM) systems has allowed for identification of blood sugar variations and trends in real-time that is not feasible with conventional self-monitoring of blood glucose. However, there is inconsistent data to show that the use of CGM leads to better glycemic control as measured by Hemoglobin A1c (HbA1c) in pediatric patients with type 1 diabetes mellitus. Our study aimed to compare the average HbA1c level in the 1–2 years prior to starting a CGM to the average HbA1c level in the 1–2 years immediately following CGM initiation in a sample of 1–20 year olds with type 1 diabetes mellitus.


Participants were 90 youth (ages 1–20) followed for type 1 diabetes care at our institution who used a CGM for at least a 6 month time period. We performed a retrospective chart review to obtain up to four HbA1c values pre and post-CGM initiation each. We evaluated pre- and post-CGM initiation changes in mean HbA1c via dependent samples t-tests using IBM SPSS 24.0.


The mean HbA1c was 8.7% pre-CGM and decreased to 8.27% 9–12 months after CGM initiation in the overall sample. A statistically significant decrease in HbA1c was seen in patients who used multiple daily injections (p=0.02), those with a pre-CGM HbA1c greater than 9% (p=0.01), and those with a diabetes duration of 5–10 years (p=0.02).


CGM use was associated with a decrease in HbA1c over time which was statistically significant in some subgroups.

Corresponding author: Shilpa Gurnurkar, MD, Nemours Children’s Hospital, 13535 Nemours Parkway, Orlando, FL32827, USA, E-mail:


The authors would like to thank Dr. Jessica Pierce for reviewing the manuscript and providing valuable feedback

  1. Research funding: None declared.

  2. Author contributions: SG and LO prepared the study design. LO performed data collection. SC performed the statistical analysis. All authors analyzed and reviewed results and were involved in preparing the manuscript. All authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  3. Competing interests: Authors state no conflict of interest.

  4. Ethical approval: Research involving human subjects complied with all relevant national regulations, institutional policies and is in accordance with the tenets of the Helsinki Declaration (as revised in 2013), and has been approved by the Nemours Children’s Hospital’s Institutional Review Board (IRB number: 1404703).


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Received: 2020-10-13
Accepted: 2020-12-04
Published Online: 2021-02-23
Published in Print: 2021-03-26

© 2021 Walter de Gruyter GmbH, Berlin/Boston

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