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)

Age-dependent FRAX-based assessment and intervention thresholds for therapeutic decision making in osteoporosis in the Malaysian population

Fracture risk stratification is crucial in countries with limited access to bone density measurement. 24.8% women were in the high-risk category while 30.4% were in the low-risk category. In the intermediate risk group, after recalculation of fracture risk with bone density, 38.3% required treatment. In more than half, treatment decisions can be made without bone density.

PURPOSE

We aimed to examine the role of age-dependent intervention thresholds (ITs) applied to the Fracture Risk Assessment (FRAX) tool in therapeutic decision making for osteoporosis in the Malaysian population.

METHODS

Data were collated from 1380 treatment-naïve postmenopausal women aged 40-85 years who underwent bone mineral density (BMD) measurements for clinical reasons. Age-dependent ITs, for both major osteoporotic fracture (MOF) and hip fracture (HF), were calculated considering a woman with a BMI of 25 kg/m2, aged between 40 and 85years, with a prior fragility fracture, sans other clinical risk factors. Those with fracture probabilities equal to or above upper assessment thresholds (UATs) were considered to have high fracture risk. Those below the lower assessment thresholds (LATs) were considered to have low fracture risk.

RESULTS

The ITs of MOF and HF ranged from 0.7 to 18% and 0.2 to 8%, between 40 and 85years. The LATs of MOF ranged from 0.3 to 11%, while those of HF ranged from 0.1 to 5.2%. The UATs of MOF and HF were 0.8 to 21.6% and 0.2 to 9.6%, respectively. In this study, 24.8% women were in the high-risk category while 30.4% were in the low-risk category. Of the 44.8% (n=618) in the intermediate risk group, after recalculation of fracture risk with BMD input, 38.3% (237/618) were above the ITs while the rest (n=381, 61.7%) were below the ITs. Judged by the Youden Index, 11.5% MOF probability which was associated with a sensitivity of 0.62 and specificity of 0.83 and 4.0% HF probability associated with a sensitivity of 0.63 and a specificity 0.82 were found to be the most appropriate fixed ITs in this analysis.

CONCLUSION

Less than half of the study population (44.8%) required BMD for osteoporosis management when age-specific assessment thresholds were applied. Therefore, in more than half, therapeutic decisions can be made without BMD based on these assessment thresholds.

Clinical practice guidelines for the prevention and treatment of osteoporosis in Taiwan: 2022 update

Osteoporosis greatly increases the risk of fractures. Osteoporotic fractures negatively impact quality of life, increase the burden of care, and increase mortality. Taiwan is an area with a high prevalence of osteoporosis. This updated summary of guidelines has been developed by experts of the Taiwan Osteoporosis Association with the intention of reducing the risks of osteoporotic fractures and improving the quality of care for patients with osteoporosis. The updated guidelines compile the latest evidence to provide clinicians and other healthcare professionals with practical recommendations for the prevention, diagnosis, and management of osteoporosis under clinical settings in Taiwan.

FRAX score with and without bone mineral density: a comparison and factors affecting the discordance in osteoporosis treatment in Thais

We investigate the rate of concordance between treatment recommendations of osteoporosis with 10-year probability of hip fracture calculated using FRAX scores with and without BMD. We found that predictions were concordant in 83.8% of patients. However, older age, lower BMD, and FRAX without BMD around the intervention threshold were associated with discordant results. In the discordant group, FRAX with BMD suggested treatment in more participants with lower age, higher BMI, and lower BMD when compared with FRAX without BMD.

INTRODUCTION

The Fracture Risk Assessment Tool (FRAX) is used to calculate the 10-year probability of fracture using important clinical factors, with bone mineral density (BMD) as an optional input variable. We aimed to determine the rate of concordance between treatment recommendations of osteoporosis with 10-year probability of hip fracture calculated using FRAX scores with and without BMD and to identify relevant clinical risk factors associated with discordance.

METHODS

This was a cross-sectional study conducted in patients between 40 and 90 years of age who were screened for osteoporosis by BMD measurement using dual energy X-ray absorptiometry (DXA) from 2010 to 2018 at a university hospital in Thailand. A FRAX questionnaire was administered to determine demographic data and osteoporotic risk factors. FRAX scores with and without BMD were calculated for each participant using the Thai reference, and patients were categorized into either the treatment or non-treatment group based on a cut-off of 3% 10-year probability of hip fracture. When FRAX scores with and without BMD results were consistent, they were considered concordant. Otherwise, they were deemed discordant. Clinical risk factors were compared between the concordant and discordant groups.

RESULTS

A total of 3545 participants were included in the study. The majority (83.8%) were in the concordant group. However, older age, lower BMD, and FRAX without BMD around the intervention threshold were significantly associated with discordant results. In the discordant group, FRAX with BMD suggested treatment in more participants with lower age, higher BMI, and lower BMD when compared with FRAX without BMD.

CONCLUSION

FRAX scores with and without BMD yielded concordant predictions regarding the 10-year probability of hip fracture suggesting pharmacological treatment. However, this concordance declined in elderly and osteoporotic participants and in those with FRAX without BMD around intervention threshold. BMD data may be required in these populations in order to facilitate accurate risk assessment.