title: Using Super-Imposition by Translation And Rotation (SITAR) to relate pubertal growth to bone health in later life: the Medical Research Council (MRC) National Survey of Health and Development.
abstract: To explore associations between pubertal growth and later bone health in a cohort with infrequent measurements, using another cohort with more frequent measurements to support the modelling, data from the Medical Research Council (MRC) National Survey of Health and Development (2-26 years, 4901/30 004 subjects/measurements) and the Avon Longitudinal Study of Parents And Children (ALSPAC) (5-20 years) (10 896/74 120) were related to National Survey of Health and Development (NSHD) bone health outcomes at 60-64 years.
  
  
  
  NSHD data were analysed using Super-Imposition by Translation And Rotation (SITAR) growth curve analysis, either alone or jointly with ALSPAC data. Improved estimation of pubertal growth parameters of size, tempo and velocity was assessed by changes in model fit and correlations with contemporary measures of pubertal timing. Bone outcomes of radius [trabecular volumetric bone mineral density (vBMD) and diaphysis cross-sectional area (CSA)] were regressed on the SITAR parameters, adjusted for current body size.
  
  
  
  The NSHD SITAR parameters were better estimated in conjunction with ALSPAC, i.e. more strongly correlated with pubertal timing. Trabecular vBMD was associated with early height tempo, whereas diaphysis CSA was related to weight size, early tempo and slow velocity, the bone outcomes being around 15% higher for the better vs worse growth pattern.
  
  
  
  By pooling NSHD and ALSPAC data, SITAR more accurately summarized pubertal growth and weight gain in NSHD, and in turn demonstrated notable associations between pubertal timing and later bone outcomes. These associations give insight into the importance of the pubertal period for future skeletal health and osteoporosis risk.
authors.affiliation: Population, Policy and Practice Programme, UCL Institute of Child Health, London, UK, tim.cole@ucl.ac.uk.
authors.forename: T J
authors.initials: TJ
authors.lastname: Cole
authors.affiliation: MRC Unit for Lifelong Health and Ageing at UCL, London, UK.
authors.forename: D
authors.initials: D
authors.lastname: Kuh
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, UK.
authors.forename: W
authors.initials: W
authors.lastname: Johnson
authors.affiliation: MRC Human Nutrition Research, Cambridge, UK.
authors.forename: K A
authors.initials: KA
authors.lastname: Ward
authors.affiliation: MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: L D
authors.initials: LD
authors.lastname: Howe
authors.affiliation: Clinical Radiology and Academic Health Science Centre, Manchester Royal Infirmary & University, Manchester, UK and.
authors.forename: J E
authors.initials: JE
authors.lastname: Adams
authors.affiliation: MRC Unit for Lifelong Health and Ageing at UCL, London, UK.
authors.forename: R
authors.initials: R
authors.lastname: Hardy
authors.affiliation: MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge, UK.
authors.forename: K K
authors.initials: KK
authors.lastname: Ong
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001827:Body Height; D015519:Bone Density; D002648:Child; D002675:Child, Preschool; D005260:Female; D057238:Growth Charts; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010024:Osteoporosis / Q000000981:diagnostic imaging; D011627:Puberty / Q000502:physiology*; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D006113:United Kingdom; D015430:Weight Gain; D055815:Young Adult
keywords: SITAR; ageing; bone; density; height; puberty; weight