title: Tracking of size-adjusted bone mineral content and bone area in boys and girls from 10 to 17 years of age.
abstract: Positive correlations for bone mineral content (BMC) between 10 and 17 years of age were found for boys and girls after adjusting for body size, puberty, and diet. This tracking of BMC indicated that osteoporosis prevention should begin already in prepuberty.
  
  
  BACKGROUND
  Previous studies indicate that BMC is tracking during growth, but it remains unclear whether this would remain significant after adjusting for important confounders. We tested the hypothesis that BMC and bone area (BA) track from 10 to 17 years of age, independently of body size, pubertal stage, and dietary intake of energy, calcium and protein.
  
  
  METHODS
  A longitudinal study where whole body (T) and lumbar spine (LS) BMC and BA (dual-energy X-ray absorptiometry) and dietary intake (7-day food records) were assessed at 10 and 17 years of age in boys and girls (n = 91). Tracking of bone variables from 10 to 17 years was estimated by Pearson's correlations adjusted for the selected confounders.
  
  
  RESULTS
  The unadjusted correlations for T-BMC between 10 and 17 years, likewise for LS-BMC and T-BA, were positive for both sexes (0.51-0.81; P < 0.0001) and remained significant after correcting for the selected confounders. The unadjusted correlations for LS-BA between 10 and 17 years were significant only for girls (0.29; P < 0.05), but not after further corrections.
  
  
  CONCLUSIONS
  Bone mass tracks from 10 to 17 years of age in boys and girls, especially after accounting for important confounders, indicating that osteoporosis prevention should begin in early stages of bone development.
authors.affiliation: Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark. alzb@life.ku.dk
authors.forename: A Z
authors.initials: AZ
authors.lastname: Budek
authors.forename: T
authors.initials: T
authors.lastname: Mark
authors.forename: K F
authors.initials: KF
authors.lastname: Michaelsen
authors.forename: C
authors.initials: C
authors.lastname: Mølgaard
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000293:Adolescent; D000375:Aging / Q000502:physiology*; D000886:Anthropometry / Q000379:methods; D015519:Bone Density / Q000502:physiology*; D001846:Bone Development / Q000502:physiology*; D001842:Bone and Bones / Q000033:anatomy & histology; D002648:Child; D004032:Diet / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000254:growth & development / Q000502:physiology; D008297:Male; D011627:Puberty / Q000502:physiology; D012727:Sex Characteristics