690-P: Deterioration in Glycemic Control on School Days among School-Aged Children with Type 1 Diabetes: A Continuous Glucose Monitoring–Based Study

Abstract

Background: Children with type 1 diabetes (T1D) spend more time in school when they turn school age. The impact of such transition on glycemic control remains unclear. We aimed to investigate the impact of school life by comparing the glycemic control between holidays and schooldays in school-aged children with T1D. Methods: This observational study collected data from school aged T1D children with continuous glucose monitoring (CGM) data from September 20to July 2021. Eligible datasets should include CGM records for at least 3 schooldays and 3 holidays. Data providers’ demographic and lifestyle-related information were collected via questionnaires. We compared the CGM metrics between schooldays and holidays using paired T-test. Results: A total of 78 school aged children with T1D were included (40 boys, median age 9.75 years, median diabetes duration 2.20 years) . 142,945 hours of CGM data were analyzed. Overall, time in range (3.9-7.8 mmol/L, TIR) was better on holidays than that during schooldays [57.0% (SD 15.0%) vs. 55.9% (SD 15.1%) , p = 0.039] and time above range (>7.8mmol/L, TAR) was lower on holidays [35.8% (SD 15.5%) vs. 36.9% (SD 15.5%) , p = 0.085]. No significant difference was observed in time spent <3.9mmol/L or numbers of hypoglycemia events per week. Nocturnal glycemic deterioration could be attributed to a significantly longer nighttime (0am to 6am) TIR [60.4% (SD 17.1%) vs. 56.9% (SD 18.1%) , p = 0.001] and a shorter nighttime TAR [31.8% (SD 17.5%) vs. 35.6% (SD 18.5%) , p = 0.001] on holidays compared with those on schooldays, with no difference in daytime metrics. Stratified analysis revealed the nocturnal difference was more prone to children aged 6 to years, girls, and insulin pump users, while bedtime and midnight snacks had no impact. Conclusion: Among school-aged children with T1D, deterioration in nocturnal glycemic control was found in schooldays and active adjustment in treatment is needed to improve schooldays glycemia. Disclosure X.Wu: None. W.Zhang: None. Y.Ding: None. X.Zheng: None. J.Weng: None. S.Luo: None.