Introduction Bone mineral density (BMD) is a key determinant of osteoporotic fracture risk; however, the association between femoral neck BMD and fracture burden across different sex and age groups remains incompletely characterized. Methods We conducted a cross-sectional analysis using NHANES data from 2005–2010, 2013–2014, and 2017–March 2020. Participants aged ≥50 with femur neck BMD and fracture history were included. Survey-weighted negative binomial regression models and restricted cubic spline analyses were applied to evaluate the association between femoral neck BMD and osteoporotic fracture counts, with stratified analyses by sex and age. Results In fully adjusted models, higher femoral neck BMD was associated with lower hip and total osteoporotic fracture counts. Restricted cubic spline analyses demonstrated a nonlinear inverse association between femoral neck BMD and predicted fracture counts. Sex- and age-stratified analyses revealed substantial heterogeneity in these associations, with a stronger inverse relationship observed among older adults, with more consistent inverse patterns among females and age-dependent associations among males. Discussion Femoral neck BMD is inversely associated with osteoporotic fracture burden in U.S. adults aged ≥50 years, with marked variation by sex and age. These findings highlight the importance of considering demographic heterogeneity when assessing fracture risk using BMD measurements.
Wan et al. (Wed,) studied this question.