Correlation Between A1c and Continuous Glucose Monitor Time in Range in a Cohort of Pediatric Patients with Type 1 Diabetes.

Abstract

Hemoglobin A1c (A1c) is the standard for glycemic control in type 1 diabetes. With recent increase in continuous glucose monitoring (CGM), other metrics (time in range 70-180 mg/dL [TIR]) are increasingly available. Data are limited for youth. We evaluated the association between A1c and time in range in a large pediatric cohort. We included patients from 2018 through 2020, aged <22 years with ≥70% CGM usage (n = 2393). A linear correlation between A1c and TIR was observed (correlation coefficient -0.73), similar to studies in adults. Each 1% increase in A1c was associated with a 9.1% lower TIR. The R² for A1c versus mean sensor glucose was 0.66 (P < 0.001) and A1c versus TIR was 0.55 (P < 0.001). TIR correlates with A1c in children with type 1 diabetes. TIR should be considered alongside A1c. Further research is warranted to establish long-term outcomes associated with TIR in children.