Background: Glucose variability is an emerging risk factor for diabetes complications. As basal insulin requirements vary in youth with T1D by age and time of day, we analyzed daily patterns of glucose variation by pubertal stage in youth with T1D.

Methods: Glucose patterns were assessed using 4 weeks of continuous glucose monitoring (CGM) data from 107 youth ages 8-17 years with T1D for >1 year. Glucose values per hour were expressed as percentages relative to the mean glucose over a 24-hour period. Glucose patterns were compared by pubertal stage (pre-pubertal: Tanner (T) 1, pubertal: T2-4, post-pubertal: T5).

Results: The sample had a mean (±SD) age of 13.1±2.6 years, T1D duration of 6.3±3.5 years, A1c of 7.8±0.8; 88% were pump-treated. Pre-pubertal youth had greater mean standard deviation (86.4±12.0, p=.008) and coefficient of variation (0.43±.05, p=.04) compared to pubertal (79.8±13.4; 0.41±.05) and post-pubertal youth (75.8±13.3; 0.40±.05). There was no difference in mean glucose or A1c by pubertal stage (p >.4). Patterns of glucose variation appear in Figure.

Conclusion: Pre-pubertal compared with pubertal and post-pubertal youth appear to have greater glucose variability independent of A1c, with a notable dawn-dusk pattern. Thus, A1c alone does not seem to capture the full range of glycemic parameters in youth with T1D, highlighting the added value of CGM data when determining optimal insulin doses.


J. Zhu: None. L. Volkening: None. M. Katz: None. L.M. Laffel: Consultant; Self; Eli Lilly and Company, Novo Nordisk Inc., Sanofi US, MannKind Corporation, Roche Diagnostics Corporation, Dexcom, Inc., Insulet Corporation, AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Johnson & Johnson Diabetes Institute, LLC..

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