Aim: To evaluate clinical and genetic factors, besides pancreatic insufficiency, associated with increased risk of cystic fibrosis-related diabetes.
Methods: Case-control (1:1) study on 138 cystic fibrosis patients. Data were collected on gender, age at diagnosis, reason for cystic fibrosis diagnosis, family history of type 1 or 2 diabetes mellitus, pre-existing severe liver disease, and class of cystic fibrosis transmembrane regulation mutation. Moreover, information was obtained on lung involvement and degree of exocrine pancreatic insufficiency evaluated 1 year before the diagnosis of cystic fibrosis-related diabetes in patients and age-matched controls.
Results: Compared to controls, patients with cystic fibrosis-related diabetes had a higher probability of having already been diagnosed with liver disease (16.7% versus 1.7%, OR = 11.6, 95% CI 1.43-93.0). Moreover, in the year before diabetes onset, cases had slightly worse pulmonary function compared to controls (FEV1 = 58.4 +/- 27% predicted versus 67.4 +/- 21% predicted; p = 0.05). No significant effects related to the other factors considered were found.
Conclusion: Severe liver disease was found to significantly increase the risk of developing cystic fibrosis-related diabetes. Patients with liver disease should be scheduled for earlier diabetes screening in order to identify and possibly treat glucose intolerance.