ESPE Abstracts

Background and Aim: Cystic fibrosis-related diabetes (CFRD) is a common extrapulmonary comorbidity in patients with cystic fibrosis (CF). Since CFRD is clinically silent in the early period, it is recommended to evaluate glucose metabolism with an oral glucose tolerance test (OGTT) annually in CF patients aged 10 years and older. Insulin therapy is thought to improve lung function and nutritional status in patients with CFRD. In this study, we aimed to evaluate the glucose metabolism of patients with CF and clinical outcome in those who received insulin therapy.

Methods: 269 patients (132 girls, 137 boys) followed with the diagnosis of CF who had OGTT in the last 5 years were included in the study. Although 19 (7.1%) of the cases were under 10 years of age, OGTT was performed because they had symptoms or HbA1c levels suggestive of hyperglycemia. The clinical features of the patients, anthropometric measurements, pulmonary function tests (PFTs), OGTT, HbA1c, and the number of acute pulmonary exacerbations requiring oral/intravenous antibiotic treatment were examined retrospectively. The number of pulmonary exacerbations, anthropometric measurements and PFTs one year before and one year after the insulin therapy were compared in those receiving insulin.

Results: The mean age was 12.9±2.9 years (range: 6-18). 89.6% (241/269) had exocrine pancreatic insufficiency. OGTT revealed that 37 (13.8%) patients had CFRD, 18 (6.7%) had impaired fasting glucose (IFG), 47 (17.5 %) had impaired glucose tolerance (IGT) and 9 (3.3%) had IFG+IGT. Insulin therapy was started in 89.2% (33/37) of patients with CFRD and 32.1% (18/56) of total number of patients with IGT. Forty-one percent of the patients (21/51) were started only long-acting insulin analogue (insulin glargine), while 8% (4/51) were given rapid acting insulin analogue (lispro) during meals, and the remaining were received both basal and bolus insulin (51%, 26/51 glargine and lispro). Carbohydrates were not restricted. Insulin therapy led to a decrease in the number of pulmonary exacerbations requiring intravenous antibiotic treatment, an increase in FEV1, FVC, FEV1/FVC, MEF 25-75, a decrease in HbA1c levels, and an increase in BMI-SDS one year after the onset of therapy (P<0.05).

Conclusion: Insulin improves respiratory functions, decreases the number of pulmonary exacerbations requiring treatment, and increases BMI-SDS in CF with glucose metabolism disorders. Close monitoring of glucose metabolism, and early initiation of insulin therapy are important in patients with CF.