Diabetes in cystic fibrosis: A 2008 state of the art

Cystic fibrosis (CF), a common autosomal recessive condition, often involves the CFTR ΔF508 mutation in the homo- or heterozygous state. Due to continuously improving survival rates, a secondary form of diabetes mellitus (cystic fibrosis-related diabetes or CFRD) is now becoming a major comorbidity associated with CF. The etiopathogeny of CFRD is usually ascribed to pancreatic exocrine/endocrine insufficiency which itself correlates with CFTR mutation. While insulin deficiency seems to play the major role in CFRD, a relative insulin resistance component was also proposed. In a local cohort of seventy-six patients with the ΔF508 mutation, we demonstrate using HOMA (Homeostasis Model Assessment) that impairment of the true underlying insulin secretion, as reflected by (B × S), is the hallmark of (pre)diabetes in CF. The initiation of insulin therapy is associated with a significant increase in body mass index as well as a trend towards improvement in lung function. Regular screening for (pre)diabetes in CF should on that ground be performed on a regular basis.