P-404: Simplified BOLUS strategy improves glycemic outcomes in a low-adherence adolescent using hybrid closed-loop therapy
T Marin, B Ropoli, F Colombo, G Oliveira, L Trevisan, M F Paulino, M ZorronAbstract
Introduction
Suboptimal adherence to carbohydrate counting and meal bolusing remains a major limitation to the effectiveness of hybrid closed-loop systems in adolescents with type 1 diabetes.
Objectives
To evaluate the impact of a simplified fixed-meal bolus strategy on glycemic outcomes and system use in a low-adherence adolescent using AHCL therapy.
Methods
Case report of an 18-year-old individual with T1D followed in a tertiary care center in Brazil and using continuous subcutaneous insulin infusion for six years. The patient demonstrated persistent low adherence, including missed meal boluses and inconsistent continuous glucose monitoring (CGM) use. A multidisciplinary intervention was implemented, including a simplified fixed-carbohydrate meal plan tailored to habitual intake, structured education, and psychological support. Continuous glucose monitoring metrics before and after the intervention were compared.
Results
Prior to the intervention, CGM use was 24%, with time in range (TIR 70–180 mg/dL) of 50% and frequent hyperglycemia. Following the intervention, CGM use increased to 61%, and AHCL utilization improved. TIR increased to 73%, with reduced time above range and no increase in hypoglycemia. The patient demonstrated improvedengagement with therapy and greater flexibility in food choices within structured meal patterns.
Conclusions
A simplified fixed-meal bolus strategy combined with multidisciplinary support improved glycemic outcomes and engagement in an adolescent with low adherence tocarbohydrate counting. This approach may enhance real-world effectiveness of hybrid closed-loop systems in patients unable to perform carbohydrate counting. This approach may enhance real-world effectiveness of hybrid closed-loop systems in patients unable to perform carbohydrate counting.