title: Pubertal timing predicts previous fractures and BMD in young adult men: the GOOD study.
abstract: The importance of pubertal timing for adult BMD in males was studied through association of pubertal timing with young adult bone phenotype. Pubertal timing was found to predict both cortical and trabecular volumetric BMD and previous fractures in young adult men. Thus, late puberty is a risk factor for low BMD and previous fractures in young adult men.
  
  
  BACKGROUND
  Peak bone mass (PBM), achieved during puberty, is a determinant of the risk for osteoporosis and future fractures. The role of variations within the normal range in pubertal timing for fractures during pubertal development and for adult bone mass in men is unknown.
  
  
  METHODS
  The aim of this study was to investigate the importance of pubertal timing for adult BMD and for fractures before achievement of PBM in men. The population-based Gothenburg Osteoporosis and Obesity Determinants (GOOD) study is a well-characterized cohort of young adult Swedish males 18-20 years of age. Detailed growth charts from birth to 18-20 years of age were retrieved for 642 men participating in the GOOD study. Age at peak height velocity (PHV) was estimated and used as an assessment of pubertal timing. The skeletal phenotype was analyzed at young adult age using DXA and pQCT and previous fractures were assessed by questionnaires.
  
  
  RESULTS
  Age at PHV was a negative independent predictor of both adult cortical and trabecular volumetric BMD and of total body and radius areal BMD. Moreover, age at PHV was associated with previous fractures in a logistic regression analysis. The OR for cortical osteopenia was 2.49 (95% CI, 1.91-3.24; p < 0.001) and for previous upper limb fractures was 1.35 (95% CI, 1.04-1.75; p < 0.05) per year increment in age at PHV.
  
  
  CONCLUSIONS
  Age at PHV is a negative independent predictor of BMD and a positive predictor of previous fractures in young adult men. Longitudinal studies to determine if pubertal timing also predicts BMD and fractures in elderly men are required.
authors.affiliation: Bone Research Center, Department of Medicine, The Sahlgrenska Academy at Gothenburg University, Sweden. jenny.kindblom@medic.gu.se
authors.forename: Jenny M
authors.initials: JM
authors.lastname: Kindblom
authors.forename: Mattias
authors.initials: M
authors.lastname: Lorentzon
authors.forename: Ensio
authors.initials: E
authors.lastname: Norjavaara
authors.forename: Asa
authors.initials: A
authors.lastname: Hellqvist
authors.forename: Staffan
authors.initials: S
authors.lastname: Nilsson
authors.forename: Dan
authors.initials: D
authors.lastname: Mellström
authors.forename: Claes
authors.initials: C
authors.lastname: Ohlsson
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D017668:Age of Onset; D015519:Bone Density; D015331:Cohort Studies; D050723:Fractures, Bone / Q000453:epidemiology*; D006801:Humans; D008297:Male; D011627:Puberty; D014057:Tomography, X-Ray Computed