title: Bone density in children and adolescents with cystic fibrosis.
abstract: OBJECTIVE
  To assess bone mineralization in children and adolescents with cystic fibrosis.
  
  
  METHODS
  A cross-sectional, observational study of bone mineral density (BMD) in the lumbar vertebrae and the proximal femur of 62 patients aged 4.9 to 17.8 years (mean, 10.7 years). The age-normalized BMD findings (z scores) were correlated with multiple variables, including measures of pulmonary disease, nutritional status and growth, genotype, calcium intake, and serum 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels.
  
  
  RESULTS
  The mean BMD z score was -1.03 +/- 0.14 (+/- SE) in the lumbar vertebrae and -0.71 +/- 0.17 in the proximal femur. The BMD in this age range declined relative to normal values at a rapid rate of roughly 1 SD every 6 to 8 years. The BMD z scores correlated well with multiple measures of disease severity, particularly weight and forced expiratory volume in 1 second.
  
  
  CONCLUSIONS
  Significant osteoporosis in adults with CF results at least in part from a failure to accumulate bone mineral at a normal rate during skeletal growth and development. The cause of this is likely multifactorial. With increasing longevity, the skeletal consequences of CF become an important consideration.
authors.affiliation: Department of Orthopedics, University of North Carolina, Chapel Hill 27599-7055, USA.
authors.forename: R C
authors.initials: RC
authors.lastname: Henderson
authors.forename: C D
authors.initials: CD
authors.lastname: Madsen
mesh_terms: D000293:Adolescent; D015519:Bone Density / Q000502:physiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis