Endocrine Abstracts

Cystic fibrosis-related diabetes mellitus (CFRD) is a common complication in people living with cystic fibrosis. Dysglycaemia is associated with adverse outcomes, including reduced pulmonary function. We assessed the impact of initiating hybrid closed-loop (HCL) insulin pump therapy on glycaemic indices in individuals with CFRD. We reviewed the clinical records of all patients with CFRD who commenced HCL therapy between 2023 and 2025. HbA; ¹c and continuous glucose monitoring (CGM) data prior to HCL initiation were compared to the same indices at 3 months post-HCL. Descriptive statistics and paired t-tests were used for analysis. In total, 10 individuals with CFRD were included. The mean age was 39 (±8.49) years, and 80% were female. Before HCL therapy, the mean HbA; ¹c was 72 (±16.9) mmol/mol, time in range (TIR) was 36.6%, and time below range (TBR) was 0.8%. Six patients used the Tandem t:slim X 2™ insulin pump system, and four used the Medtronic MiniMed™ ⁷⁸⁰G system. Three months after starting HCL, the mean HbA; ¹c had improved to 57 (±7.4) mmol/mol, TIR increased to 66%, and TBR remained low at 0.5%. There was a statistically significant improvement in HbA; ¹c (P = 0.03) and in TIR (P < 0.0001). This case series highlights the impact of HCL insulin pump therapy on glycaemic control in people with CFRD. The observed improvements in HbA; ¹c and TIR, without an increase in hypoglycaemia, suggest potential for better long-term outcomes in this population.