Background: Glycosylated haemoglobin (HbA1c) and time spent in the target glucose range (TIR) are traditional markers for glycaemic control in diabetic patients. Targets for these markers are well established in order to prevent diabetes related complications. These targets are easier to obtain through use of more advanced insulin delivery systems such as advanced hybrid closed loop (AHCL) devices. The primary aim of the study is to assess the impact of transitioning to AHCL on glycaemic metric profile, including TIR and HbA1c. The secondary aim of the study is to compare the diabetic population in the clinic to international targets described for HbA1c and TIR.Methods: This is a retrospective cohort study conducted in a single centre level 2 paediatric/adolescent diabetic clinic. Charts were audited for all paediatric patient who were commenced on or transitioned to AHCL between January 2024 and December 2024. Data gathered including HbA1c and TIR pre AHCL and at least 6 months post transition to AHCL.Results: Complete data was collected on fifty-seven patients. The mean HbA1c PreAHCL was 8.4% (SD +/-1.39, CI 8.0, 8.8). Eight of the Fifty seven patients (14%) had a pre transitioning HbA1c below or equal to the international target of 7%. After transitioning to AHCL this increased to 20 patients (35.1%) achieving an hbA1c of 7% or less. 6 patients on AHCL had an HbA1c of less than or equal to 6.5% (10.5%). The mean HbA1c post AHCL was 7.4 %( SD +/-0.86, CI 7.19, 7.67). The mean change in HbA1c post AHCL was -1.03 %(CI -1.3, -0.76) This is statistically significant with a p-value < 0.001. This improvement in HbA1c was more notable in the adolescent group.Four of the fifty seven (7.01%) patients spent more than or equal to 70% of time within target glycaemic range pre transitioning to ACLH. Post ACLH this increased to twenty four patients (42.10%). The mean TIR PreACLH was 39.77% (SD +/- 21.13, CI 34.77, 44.78). The mean TIR postAHCL was 66.19% (SD +/- 9.59), CI 63.65, 68.74). The mean increase in TIR was 26.42% (CI 21.42, 31.42). This is statistically significant with a p-value < 0.001. This improvement was more notable in the adolescent group.(INSERT IMAGE HERE)Conclusion: Transitioning to newer diabetes management technologies such as AHCL has significant improvement on HbA1c and TIR. This improved glycaemic profile is more notable in the adolescent population compared to the preadolescent population. This is particularly significant given that the adolescent population generally experiences a decline in glycaemic control. Follow-up of this cohort should be done to assess the sustainability of improved glycaemic control over time. Low overall percentages of patients meeting TIR and HbA1c targets needs to be addressed, although this is in keeping with the described minority of patients meeting targets at a global level.
