Hip fracture prevalence in grandfathers is associated with reduced cortical cross-sectional bone area in their young adult grandsons

Context: Parent hip fracture prevalence is a known risk factor for osteoporosis. The role of hip fracture prevalence in grandparents on areal bone mineral density (aBMD) and bone size in their grandsons remains unknown. Objective: The objective of the study was to examine whether hip fracture prevalence in grandparents was associated with lower aBMD and reduced cortical bone size in their grandsons. Design and Setting: This was a population-based cohort study in Sweden. Study Subjects: Subjects included 1015 grandsons (18.9 \ub1 0.6) (mean \ub1 sd) and 3688 grandparents. Main Outcome Measures: aBMD, cortical bone size, volumetric bone mineral density and polar strength strain index of the cortex in the grandsons in relation to hip fracture prevalence in their grandparents were measured. Results: Grandsons of grandparents with hip fracture (n = 269) had lower aBMD at the total body, radius, and lumbar spine, but not at the hip, as well as reduced cortical cross-sectional area at the radius (