Continuous Glucose Monitoring and OGTT Screen for Cystic Fibrosis Related Diabetes in Cystic Fibrosis

Cystic Fibrosis (CF) related diabetes (CFRD) is a unique form of diabetes mellitus, different from type 1 diabetes and type 2 diabetes. The diagnosis of CFRD is associated with a decline in pulmonary function, decreased nutritional status, and increased mortality. CFRD is extremely common in people with CF, occurring in approximately 40-50% of adults with CF. Impaired glucose tolerance or dysglycemia is also very common in CF. It is standard of care to screen for CFRD annually from the age of 10 years with a two-hour Oral Glucose Tolerance Test (OGTT) with 75 g dextrose. The gold standard screening for CFRD is the OGTT which is problematic as it is time consuming for patient and staff and adherence to annual screening is low among CF centers.

Survival has improved dramatically with the advent of CFTR modulators and it is presumed that the incidence of CFRD will increase with increased life expectancy. The Cystic Fibrosis Foundation (CFF) has developed the oldest disease specific patient registry, consisting of approximately 35000 patients, so there is vast historical information available on individual patients and larger datasets on the CF community as a whole. Based on the 2021 CFF patient registry data, the current life expectancy for CF patients born between 2017 and 2021 is 53 years - a 15 year increase from a decade ago.