• cystic fibrosis;
  • bone mineral density;
  • vitamin D deficiency

Aim:  To investigate bone mineral status in young cystic fibrosis (CF) patients and determine risk factors related with the development of low bone mineral density (BMD).

Methods:  We determined, in 81 patients with CF, 4 to 23-years-old, BMD as well as factors, which are thought to play a role in the development of reduced BMD.

Results:  BMD Z-score was between −1 and −2.5 in 27 (33%) and lower than −2.5 in 9 (11%). Means of BMD Z-score were lower than the expected value of 0 in the three groups of children, adolescents and young adults (P = 0.004; P < 0.001; P = 0.048, respectively), but they did not differ among them (P = 0.114). Analysis showed that Shwachman–Kulczycki (SK) score, gender and levels of 25-hydroxy-vitamin D were significant predictors of BMD Z-score. Significant also was the interaction between gender and SK score.

Conclusions:  Our study supports that BMD may be reduced from a young age in CF patients though this needs to be confirmed using true volumetric measures of BMD. This defect is related to disease severity with males being more vulnerable. Inefficient levels of vitamin D are very common and contribute significantly to impaired bone health. The latter finding underlines the need for higher supplementation doses.