THE SPECTRUM OF ASSOCIATION BETWEEN HBA1C AND TIME-IN-RANGE (TIR)
- John Shin, United States of America
- John Shin, United States of America
- Toni L. Cordero, United States of America
- Xiaoxiao Chen, United States of America
- Fen Peng, United States of America
- Ohad Cohen, Switzerland
- ROBERT A. Vigersky, United States of America
Abstract
Background and Aims
There is emerging evidence of a relationship between diabetes complications and TIR which rivals that with HbA1c.1-3 Nevertheless, establishing a precise model that predicts HbA1c using TIR has been challenging and complex.4,5 The distribution of the relationship between HbA1c range and TIR was examined in participants from three MiniMed™ insulin delivery system trials.
Methods
Datasets of 211 children (7-13 years, 10.7[1.8] years) and 573 adolescents and adults (≥14 years, 41.5[17.1] years) from the three-months long MiniMed™ 670G,6,7 MiniMed™ 640G,8 and MiniMed™ 530G9 system trials were analyzed. The distributions of TIR (70-180 mg/dL) were evaluated per participant HbA1c range (<6%, 6-7%, 7.1-8%, 8.1-9%, 9.1-10%, and >10%) and R2 coefficients were calculated per TIR quintiles.
Results
A spectrum of associations between HbA1c and TIR was observed across the different trials (Figure). When data were stratified into quintiles to characterize TIR subgroups, the R2 coefficients ranged from 0.4544 (N=43) to 0.8671 (N=43) for those 7-13 years of age, and from 0.7443 (N=112) to 0.9089 (N=115) for those ≥14 years of age. Best goodness of fit was observed for participants ≥14 years.
Conclusions
The TIR quintiles from MiniMed™ insulin delivery system clinical trials demonstrated a wide variation in the degrees of glucose control within the same HbA1c range for pediatric and adult participants with type 1 diabetes. The TIR provides the quality of HbA1c that an individual patient has achieved and a basis from which to further improve glycemic control. Further studies are required to determine if TIR or HbA1c may better predict diabetes complications.
