title: Self-reported weight at birth predicts measures of femoral size but not volumetric BMD in eldery men: MrOS.
abstract: The mechanism whereby poor intrauterine growth increases risk of adult hip fracture is unclear. We report the association between birth weight and proximal femoral geometry and density in community-dwelling elderly men. We used self-reported birth weight, measured adult height and weight and proximal femoral quantitative computed tomography (QCT) measurements of femoral neck axis length, cross-sectional area, and volumetric BMD (vBMD) among the participants in the Osteoporotic Fractures in Men (MrOS), a cohort study of community-dwelling US men aged 65 and older. We compared men with birth weight <7 pounds (lower birth weight [LBW]; n = 501) and ≥ 9 pounds (higher birth weight [HBW]; n = 262) with those weighing 7-8.9 pounds (medium birth weight [MBW], referent group; n = 1068) using linear regression adjusting for current age, height, and BMI. The mean age of the 1831 men who had both birth weight and QCT measurements was 73 years (SD 5.9). Compared with the referent MBW, HBW men had concordantly longer femoral neck (+0.16 SD; p = .028) and cross-sectional area (+0.24 SD, p = .001). LBW men had a smaller cross-sectional (-0.26 SD, p < .001) but longer femoral neck for their height (+0.11 SD, p = .05). Neither cortical nor trabecular vBMD at the femoral neck was associated with birth weight. These findings support the hypothesis that the skeletal envelope, but not density, is set, in part, at birth. Further research exploring the association between early developmental factors and lifetime fracture risk is needed and may inform primary preventative strategies for fracture prevention.
authors.affiliation: NIHR Musculoskeletal BRU, University of Oxford, Oxford, United Kingdom. kassim.javaid@ndorms.ox.ac.uk
authors.forename: M Kassim
authors.initials: MK
authors.lastname: Javaid
authors.forename: Daniel
authors.initials: D
authors.lastname: Prieto-Alhambra
authors.forename: Li-Yung
authors.initials: LY
authors.lastname: Lui
authors.forename: Peggy
authors.initials: P
authors.lastname: Cawthon
authors.forename: Nigel K
authors.initials: NK
authors.lastname: Arden
authors.forename: Thomas
authors.initials: T
authors.lastname: Lang
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Lane
authors.forename: Eric
authors.initials: E
authors.lastname: Orwoll
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barrett-Conner
authors.forename: Michael C
authors.initials: MC
authors.lastname: Nevitt
authors.forename: Cyrus
authors.initials: C
authors.lastname: Cooper
authors.forename: Steven R
authors.initials: SR
authors.lastname: Cummings
mesh_terms: D000328:Adult; D000368:Aged; D001724:Birth Weight / Q000502:physiology*; D015519:Bone Density / Q000502:physiology*; D005269:Femur / Q000473:pathology* / Q000503:physiopathology*; D005272:Femur Neck / Q000000981:diagnostic imaging; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D007230:Infant, Low Birth Weight / Q000502:physiology; D007231:Infant, Newborn; D008297:Male; D009929:Organ Size; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D010388:Pelvis / Q000000981:diagnostic imaging; D057566:Self Report; D014057:Tomography, X-Ray Computed; D044465:White People