Femoral bone mineral density reference values by sex and ethnicity: Findings from the Qatar Biobank study.

Abstract

Low bone mineral density (BMD) is a major global health concern due to fracture-related morbidity and mortality. BMD is currently assessed by dual-energy X-ray absorptiometry (DXA) against a US reference population. The aim of the study was to establish an ethnicity- and sex-specific reference for calculating BMD at different femoral sites including femoral trochanter, Ward's triangle and femoral neck in Qatar. This cross-sectional study analyzed BMD in 4727 (2277 females and 2450 males) healthy Qatari aged between 20 and 82 years participating in the Qatar Biobank (QBB) study. Standard T-scores provided by the densitometer (T) were compared with ethnicity- and sex-specific T-scores for the Qatari population (T) calculated using data from the 20-29-year age group for different femoral sites as the reference. The concordance between T and T was analyzed using kappa statistics. Males consistently exhibited higher BMD values for the femoral trochanter, Ward's triangle, and the femoral neck across all age groups compared with females. Using T rather than T as a reference at any site classified fewer individuals as having osteoporosis and osteopenia, especially for females. Agreement between T and T was higher in males than in females. These findings underscore the need for local ethnicity- and sex-specific BMD reference values. The use of T significantly reduced overdiagnosis of osteopenia and osteoporosis compared with T, thereby decreasing overtreatment and impacting participant recruitment decisions into clinical studies.