Endocrine Abstracts

JOINT3767

Introduction: Cystic-fibrosis related diabetes (CFRD) is an important emerging complication of patients with cystic fibrosis (CF). This study investigated the prevalence of CFRD in the Croatian CF population, the age at CFRD diagnosis, insulin regimens used, and the relationship between age at CFRD diagnosis, insulin requirements, glycated hemoglobin (HbA1c), and body mass index (BMI).

Participants and Methods: Medical records from 157 patients with genetically and laboratory-confirmed CF were reviewed up to January 2025. All patients were followed at the Cystic fibrosis center for children and adults, University Hospital Centre Zagreb, the country’s primary treatment facility for CF. The American diabetes association (ADA) criteria were used to classify patients as CFRD. Anthropometric and clinical data were collected from the most recent medical records. Descriptive statistics were employed to summarize the prevalence and clinical characteristics of CFRD patients. Spearman’s rank correlation coefficient was used to assess the relationships between age at CFRD diagnosis, age of insulin initiation, insulin doses, HbA1c, and BMI.

Results: Seventeen out of 157 patients (10. 8%) were identified with CFRD. The prevalence of CFRD was 4. 5% (4/89) in the pediatric CF population and 19. 1% (13/68) in the adult CF population. The median age of CFRD diagnosis was 14 years (range 9 – 22 years, SD = 3. 95), with the majority diagnosed between 9 and 15 years. The median BMI of patients with CFRD was 23. 0 kg/m² (range 13. 5 – 30. 5 kg/m², SD = 3. 73) and the median age was 24 years (SD = 6. 64). Fifteen patients (88%) were receiving combination therapy with ivacaftor, tezacaftor and elexsacaftor, and one patient was using ivacaftor only. At the last visit, 76. 5% (13/17) were using insulin. One patient was treated with bolus insulin only, 53. 4% (7/13 patients) were using basal-bolus multiple daily injections, and 38. 5% (5/13) were using insulin pumps. The average total daily insulin/kg to treat diabetes was 0. 854 U/kg (SD = 0. 398). The age at CFRD diagnosis and age at insulin introduction were positively correlated with BMI (P = 0. 02853, P = 0. 0254, respectively), and total daily insulin/kg was postively correlated with HbA1c (P = 0. 03308).

Conclusion: The prevalence of CFRD in Croatia and the age at CFRD diagnosis is consistent with previous studies. Patients diagnosed at a younger age and requiring insulin earlier had lower BMIs, likely to due to a faster decline in beta cell function and an earlier onset of insulinopenia.