Parental History of Hip Fracture is Associated with Trabecular Deterioration.

Abstract

Parental history of hip fracture is an independent risk factor for fragility fracture, yet the skeletal traits underlying this risk remain poorly defined. We examined whether parental hip fracture is associated with differences in bone microarchitecture and estimated bone strength in a large, ethnically diverse cohort of older adults (n = 950; mean age 76.1 ± 6.2 yr; 71% female; 55.8% Hispanic) using high resolution peripheral quantitative computed tomography (HR-pQCT) with individual trabecula segmentation (ITS) and finite element-based analysis. Ten percent (n = 95) reported a parental hip fracture. Femoral neck aBMD was 3.8% lower in those with versus without parental history (p = .04). At the radius, the parental hip fracture group had lower adjusted trabecular rod bone volume fraction (10.6%), plate and rod number, axial BV/TV (12.2%) and plate connectivity (9.5%; all p < .05). At the tibia, parental hip fracture history was associated with lower adjusted trabecular density (8.8%), trabecular thickness (2.4%), plate and axial BV/TV (14%-15%, all p < .05), and 4%-5% lower estimated stiffness and failure load, differences that persisted after adjustment for aBMD. Patterns were similar regardless of race/ethnicity and whether parental hip fracture was maternal or paternal. Similar patterns were observed in a subset who were matched by propensity score. Individuals with a parental history of hip fracture exhibited significant microarchitectural deterioration, especially in trabecular structure at weight-bearing sites, and reduced estimated bone strength independent of areal BMD. These findings suggest that inherited deficits in trabecular morphology may contribute to familial fracture susceptibility and underscore the utility of HR-pQCT in identifying heritable skeletal fragility beyond DXA indices.