Endocrine disorders in adolescents and young adults with cystic fibrosis

Life expectancy of patients with cystic fibrosis (CF) is constantly improving. Therefore endocrine disorders in adolescents and adults with CF become more apparent. The present study evaluated endocrine disorders in adolescents and young adults with CF with and without CF-related diabetes (CFRD). Eighty-seven patients with CF (56 f, 31 m) were evaluated, including 45 patients with CFRD and 42 patients without CFRD (nCFRD). Median age was 29.9 ± 9.5 years (median ± SD) in CFRD and 25.8 ± 7.3 years in nCFRD. Follow-up data, 1.1 ± 0.4 years after initial screening, were available in 16 patients with CFRD and in 10 patients with nCFRD. Bone mineral density was measured by DXA scan. Laboratory diagnostics included the measurement of various hormones. HbA1c was 6.80 ± 1.0% in CFRD and 5.80 ± 0.3% in nCFRD (P < 0.0001). DXA scans detected a T-value (L1-L4) of -1.6 ± 1.3 in CFRD and -1.3 ± 1.1 in nCFRD (n.s.). Z-value was -1.0 ± 1.2 in CFRD and -1.1 ± 1.2 in nCFRD (n.s.). In the cohort of patients with available follow-up data the initial HbA1c of 6.75 ± 0.6% decreased to 6.55 ± 1.0% after one year in CFRD (n.s.). For nCFRD, initial HbA1c was 5.65 ± 0.4% and increased to 5.9 ± 0.4% (n.s.). The T-value of -0.9 ± 0.9 at initial screening remained stable in CFRD (0.9 ± 0.8 after one year, n.s.). For nCFRD, T-values were -1.7 ± 0.9 and -1.8 ± 1.1, respectively (n.s.). 25-OH-Vitamin D was 20.1 ± 10.8 ng/ml in all patients under supplementation of Vitamin D. Secondary hyperparathyreoidism was observed in 13.5% of the patients, associated with a severe Vitamin D deficiency. Testosterone deficiency or ovarian failure were not detected. Evaluation of ovarian function was limited due to the intake of oral contraceptives in most of the female patients. IGF-1 SDS was -0.95 ± 1.25. TPO-Abs were elevated in 38.9%. Endocrine disorders, especially CFRD and impaired bone mineral density, are common comorbidities in CF. Therefore additional endocrine care may contribute to decrease morbidity and mortality in patients with CF.