title: Association of low 25-hydroxyvitamin D concentrations with elevated parathyroid hormone concentrations and low cortical bone density in early pubertal and prepubertal Finnish girls.
abstract: BACKGROUND
  Very few studies have evaluated both parathyroid hormone (PTH) and 25-hydroxyvitamin D [25(OH)D] and their effects on bone mass in children.
  
  
  OBJECTIVE
  We studied the associations of serum 25(OH)D and intact PTH (iPTH) with bone mineral content (BMC) and bone mineral density (BMD) at different bone sites and the relation between serum 25(OH)D and iPTH in early pubertal and prepubertal Finnish girls.
  
  
  METHODS
  The subjects were 10-12-y-old girls (n = 193) at Tanner stage 1 or 2, who reported a mean (+/- SD) dietary calcium intake of 733 +/- 288 mg/d. 25(OH)D, iPTH, tartrate-resistant acid phosphatase 5b (TRAP 5b), urinary calcium excretion, BMC, areal BMD, and volumetric BMD were assessed by using different methods.
  
  
  RESULTS
  Thirty-two percent of the girls were vitamin D deficient [serum 25(OH)D < or = 25 nmol/L], and 46% of the girls had an insufficient concentration (26-40 nmol/L). iPTH and TRAP 5b concentrations were significantly higher in the deficient group than in the insufficient and sufficient groups [iPTH: 43.9 +/- 15.7 compared with 38.6 +/- 11.2 pg/L (P = 0.049) and 32.7 +/- 12.1 pg/L (P < 0.001), respectively; TRAP 5b: 12.2 +/- 2.9 compared with 11.0 +/- 2.8 U/L (P = 0.009) and 10.9 +/- 1.9 U/L (P = 0.006), respectively]. The girls in the deficient group also had significantly lower cortical volumetric BMD of the distal radius (P < 0.001) and tibia shaft (P = 0.002). High iPTH concentrations were also associated with low total-body apparent mineral density and urinary calcium excretion (P < 0.007).
  
  
  CONCLUSIONS
  Vitamin D-deficient girls have low cortical BMD and high iPTH concentrations, which are consistent with secondary hyperparathyroidism. A low vitamin D concentration accompanied by high bone resorption (TRAP 5b) may limit the accretion of bone mass in young girls.
authors.affiliation: Department of Health Sciences, University of Jyväskylä, Jyväskylä, Finland. cheng@sport.jyu.fi
authors.forename: Sulin
authors.initials: S
authors.lastname: Cheng
authors.forename: Frances
authors.initials: F
authors.lastname: Tylavsky
authors.forename: Heikki
authors.initials: H
authors.lastname: Kröger
authors.forename: Merja
authors.initials: M
authors.lastname: Kärkkäinen
authors.forename: Arja
authors.initials: A
authors.lastname: Lyytikäinen
authors.forename: Arvo
authors.initials: A
authors.lastname: Koistinen
authors.forename: Anitta
authors.initials: A
authors.lastname: Mahonen
authors.forename: Markku
authors.initials: M
authors.lastname: Alen
authors.forename: Jussi
authors.initials: J
authors.lastname: Halleen
authors.forename: Kalervo
authors.initials: K
authors.lastname: Väänänen
authors.forename: Christel
authors.initials: C
authors.lastname: Lamberg-Allardt
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D001862:Bone Resorption / Q000175:diagnosis; D002118:Calcium / Q000652:urine; D002136:Calcium, Dietary / Q000008:administration & dosage; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism; D007527:Isoenzymes / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood*; D011627:Puberty / Q000378:metabolism*; D012621:Seasons; D000071681:Tartrate-Resistant Acid Phosphatase; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D002136:Calcium, Dietary; D007527:Isoenzymes; D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D002118:Calcium