When to Use a FRAX Calculator
The FRAX calculator should be used in adults aged 40 to 90 years to estimate 10-year fracture risk, particularly when evaluating patients with low bone mineral density or risk factors for osteoporosis. 1, 2
Primary Indications for FRAX Calculator Use
- FRAX is most appropriate for adults aged 40-90 years who have not yet received treatment for osteoporosis 2, 3
- It should be used to calculate 10-year probability of hip fracture or major osteoporotic fracture in patients with risk factors for fracture 1, 4
- FRAX is particularly valuable in patients with osteopenia (T-scores between -1.0 and -2.4) to determine if pharmacologic treatment is warranted 1, 2
- For adults ≥40 years initiating glucocorticoid therapy, FRAX with glucocorticoid dose adjustment should be used within 6 months of starting treatment 1
Specific Clinical Scenarios
- For postmenopausal women and men over 50 years with low bone mass but not osteoporosis (T-scores > -2.5), FRAX helps identify those who would benefit from treatment 1, 4
- In patients on glucocorticoids, FRAX should be used with dose adjustment (increase major osteoporotic fracture risk by 1.15 and hip fracture risk by 1.2 if prednisone dose >7.5 mg/day) 1
- For patients with obesity being evaluated for osteoporosis, FRAX can help reassess fracture risk and guide treatment decisions 5
- FRAX should be used when DXA results alone may not capture full fracture risk, especially in younger populations 1
Reassessment Intervals
- For adults ≥40 years on continued glucocorticoid treatment who are not on osteoporosis medication, FRAX reassessment should be completed every 1-3 years 1
- Earlier reassessment within this timeframe is recommended for patients on very high-dose glucocorticoids (prednisone ≥30 mg/day or cumulative dose >5 gm in previous year) 1
- For patients with history of osteoporotic fracture, reassessment should be performed more frequently 1
Treatment Thresholds Based on FRAX
- According to National Osteoporosis Foundation guidelines, treatment is recommended for patients with FRAX 10-year risk scores of ≥3% for hip fracture or ≥20% for major osteoporotic fracture 1, 2
- FRAX results should guide the decision to initiate bone mineral density testing and/or osteoporosis treatment 1, 6
- In patients with low bone mass (T-scores between -1.0 and -2.4), FRAX helps identify the subset at higher fracture risk who would benefit from pharmacologic intervention 1, 2
Limitations and Considerations
- FRAX is validated only for untreated patients and should not be used to monitor treatment response 2, 3
- The calculator has limitations regarding race-specific calculations, which may lead to differences in treatment recommendations among persons with otherwise identical risk profiles 1
- FRAX does not account for dose-dependent effects of risk factors like glucocorticoids and alcohol (only binary yes/no) 1
- Fall risk is not included in the FRAX calculation but should be considered in clinical decision-making 2, 4
- The predictive accuracy of FRAX improves when BMD is included in the risk assessment calculation 1
Integration with Other Assessment Tools
- FRAX should be used alongside clinical fracture risk assessment, which includes evaluation of falls, fractures, frailty, and other risk factors 1
- When available, including BMD measurements from DXA improves the accuracy of FRAX predictions 1
- For patients <40 years of age, FRAX is not validated, and clinical risk assessment with BMD testing should be used instead 1