The effect of vitamin K supplementation on biochemical markers of bone formation in children and adolescents with cystic fibrosis

Eur J Pediatr. 2006 Aug;165(8):540-5. doi: 10.1007/s00431-006-0132-1. Epub 2006 Apr 19.

Abstract

Introduction: Impaired vitamin K status in cystic fibrosis (CF) has been considered as a newly emerged pathogenetic factor for reduced bone mineral density (BMD).

Objectives: Our aim was to evaluate the effectiveness of vitamin K supplementation in managing bone formation abnormalities in children and adolescents with CF.

Materials and methods: The statuses of vitamins K and D in relation to biochemical markers of bone metabolism and BMD were examined in 20 CF children receiving vitamin D supplements but not vitamin K supplements. Laboratory tests were carried out at the beginning of the study period and after 1 year of vitamin K supplementation (10 mg single oral dose/week) and the results were compared; the results were also compared with those of 25 healthy controls.

Results and discussion: Ten of the CF patients had BMD z-score<or=2.5 (n=5) or between -1 and -2.5 (n=5). Biochemical tests on patients before vitamin K supplementation revealed that the levels of osteoblastic activity markers, namely, bone alkaline phosphatase (BAP), serum osteocalcin (Gla-OC), serum carboxy-terminal propeptide of type I procollagen (PICP) and serum amino-terminal propeptide of type I procollagen (PINP), were significantly reduced compared with those of the controls. These patients had also lower 25-hydroxy-vitamin D (25(OH)D) and vitamin K serum levels, higher undercaboxylated osteocalcin (Glu-OC) and parathormone (PTH) levels and a higher calcium to creatinine ratio (Ca/Cr) than the controls. Vitamin K intake was associated with an increase in Gla-OC, PINP, PICP levels and a decrease in Glu-OC levels. PTH levels were lower after vitamin K supplementation without any difference in BMD z-scores.

Conclusion: Our data indicate that vitamin K supplementation may have a beneficial role in bone health in CF children.

MeSH terms

  • Adolescent
  • Alkaline Phosphatase / blood
  • Biomarkers / analysis
  • Bone Density
  • Bone Diseases, Metabolic / etiology
  • Bone Diseases, Metabolic / prevention & control
  • Calcium / analysis
  • Case-Control Studies
  • Child
  • Creatinine / analysis
  • Cystic Fibrosis / complications
  • Cystic Fibrosis / drug therapy*
  • Female
  • Humans
  • Male
  • Osteocalcin / blood
  • Osteogenesis*
  • Parathyroid Hormone / blood
  • Peptide Fragments / blood
  • Procollagen / blood
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood
  • Vitamin K / blood
  • Vitamin K / therapeutic use*
  • Vitamins / therapeutic use*

Substances

  • Biomarkers
  • Parathyroid Hormone
  • Peptide Fragments
  • Procollagen
  • Vitamins
  • procollagen Type I N-terminal peptide
  • Osteocalcin
  • Vitamin K
  • Vitamin D
  • 25-hydroxyvitamin D
  • Creatinine
  • Alkaline Phosphatase
  • Calcium