The role of bone mineral density in therapeutic decision-making using the Fracture Risk Assessment Tool (FRAX): a sub-study of the Taiwan OsteoPorosis Survey (TOPS).

Abstract

BMD is an integral component for bone strength assessment, but age-specific impacts of BMD on fracture risk assessment and therapeutic decision-making remained unclear. We aimed to investigate whether using BMD measurement changed the interpretation of the FRAX-based fracture probability assessment and treatment decision. The database was provided by the Taiwanese Osteoporosis Association (TOA) which conducted a nationwide survey of BMD. We calculated the 10-year major and hip fracture probabilities using the FRAX for each participant, either with (FRAX + BMD) or without BMD (FRAX - BMD). Age-specific individual intervention thresholds (IITs) were established using the FRAX-based fracture risk, equivalent to a woman with a prior fracture. Participants whose FRAX scores of major fracture were greater than or equal to their IITs were deemed suitable for therapeutic intervention. A total of 14,007 postmenopausal women were enrolled. Compared with FRAX + BMD, FRAX - BMD predicted lower FRAX scores in major and hip fractures in subjects aged 40-60 years; however, FRAX - BMD estimated higher risks for those aged 61-90 years. The therapeutic decision using FRAX - BMD was concordant to that using FRAX + BMD in 90.5% of the subjects, especially in the younger age group (40-70 years). FRAX - BMD identified more treatment candidates (7.7-16.4%) among those aged 71-90 years. The FRAX scores are influenced by age, irrespective of the consideration of BMD. FRAX - BMD is able to identify more subjects for therapeutic intervention in the elderly population. We should reconsider the role of BMD at different ages for therapeutic decision-making.