Characterisation of a Population of Adults Suffering From Cystic Fibrosis in a Belgian Reference Center

This research project aims to better understand the consequences of diabetes on the quality of life, respiratory function, and nutritional status of patients with cystic fibrosis followed at a Belgian reference center and to compare the quality of life of patients with cystic fibrosis depending on whether or not they have diabetes.

This is a monocentric observational cohort study combining retrospective medical record review and cross-sectional assessment using quality-of-life questionnaires in patients with cystic fibrosis(CF) with or without cystic fibrosis-related diabetes. This study aims to investigate and compare the characteristics of patients with cystic fibrosis according to the presence or absence of cystic fibrosis-related diabetes (CFRD), based on patients currently followed in one of the Belgian reference centers. The impact of diabetes, its early diagnosis, and its metabolic control will be assessed in relation to patients' nutritional and respiratory status, as well as their quality of life. The influence of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy on diabetes control will also be evaluated by comparing glycemic control parameters in patients receiving modulators with those not receiving them, and by examining these parameters before and after treatment initiation within the treated group. In addition, the impact of CFTR modulators on nutritional and respiratory status will be assessed in patients without CFRD. Quality of life will be evaluated using the SF-36 questionnaire in patients with cystic fibrosis, with and without CFRD. The quality of life of patients with CFRD will also be compared with that of an age-matched sample of patients with type 1 diabetes followed at the same hospital. Additional diabetes-related outcomes will be assessed and compared between the two groups of diabetic patients, including hypoglycemia awareness, satisfaction with diabetes treatment, and satisfaction with blood glucose monitoring. Previous studies suggest that patients with CFRD tend to report a lower overall quality of life, poorer acceptance of insulin therapy and glucose monitoring, but a better perception of hypoglycemia and a lower perceived impact of hypoglycemia on daily life.