Bone mineral status in prepubertal children with cystic fibrosis

J Pediatr. 2000 May;136(5):648-52. doi: 10.1067/mpd.2000.104271.


Objectives: To determine whether osteopenia is evident in prepubertal children with cystic fibrosis (CF) and, if so, whether it is caused by a deficiency in bone formation or increased bone resorption.

Study design: With the use of a prospective case control study design, we investigated 11 prepubertal children with CF between the ages of 8 and 12 years old and a non-CF control group matched by weight and sex. Bone density at the radius, ulnar, trochanter, femoral neck, and lumbar spine, biochemical markers of bone metabolism, calcium, vitamin D metabolites, and intact parathyroid hormone were measured in all subjects. Comparisons between the 2 groups were performed with Wilcoxon matched pairs and Fisher exact tests.

Results: Intake of total calories, calcium, phosphorus, and vitamin D was significantly greater in the CF group than in the control group. Serum 25(OH)vitamin D levels were significantly lower in the CF group: median 22 ng/mL for the CF group and 39 ng/mL for the control group (P =.02). 1,25(OH)(2) vitamin D levels were borderline or low in 7 subjects in the CF group and 2 members of the control group (P =.08, Fisher exact test). Intact parathyroid hormone levels were higher than the upper limit of normal in 4 subjects of the CF group and 1 member of the control group. Despite these biochemical abnormalities, we found no evidence of bone mineral deficiency in the CF group.

Conclusions: Prepubertal children with CF do not have bone mineral deficit compared with a weight- and sex-matched control group; however, their lower vitamin D levels may portend problems with bone mineralization during adolescence and adulthood.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bone Density* / physiology
  • Bone Resorption
  • Calcium / blood
  • Case-Control Studies
  • Child
  • Cystic Fibrosis / metabolism*
  • Diet Records
  • Female
  • Humans
  • Male
  • Parathyroid Hormone / blood
  • Phosphorus / blood
  • Prospective Studies
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood


  • Parathyroid Hormone
  • Vitamin D
  • Phosphorus
  • 1,25-dihydroxyvitamin D
  • 25-hydroxyvitamin D
  • Calcium