The importance of monitoring bone metabolism markers and vitamin D in adult patients with cystic fibrosis

Abstract

Summary. In this cross-sectional study, serum osteocalcin (a biomarker of bone formation), β-CrossLaps (a biomarker of bone resorption), and 25(OH)D were assessed in 64 adults with cystic fibrosis (CF) aged 16 to 35. We evaluated relationships between these biomarkers, bone mineral density (BMD), CF-specific clinical, genetic, anthropometric and functional parameters, serum C-reactive protein (CRP), and rate of low trauma peripheral fractures. β-CrossLaps level was significantly increased while osteocalcin concentration was normal or slightly decreased. A level of 25(OH)D was normal in 9.5 % of the patients and decreased in 90.5 % of the patients. Relationships were found between β-CrossLaps, BMD of the neck and the proximal part of the thigh and gender and between 25(OH)D and CF genotype. Bone biochemical biomarkers and 25(OH)D did not correlate with F508del and CFTRdele2,3(21kb) mutations, CPR level and fracture rate. These results provide rationale for initiating antiresorptive therapy in CF patients with low BMD and fractures and for administration of high-dose vitamin D to prevent bone mass reduction.