What is the FRAX Score?
The Fracture Risk Assessment Tool (FRAX) is a digital algorithm developed by the World Health Organization (WHO) to estimate a person's 10-year probability of having a major osteoporotic fracture, including fractures of the hip, spine, forearm, and shoulder. It uses several clinical risk factors to provide a comprehensive view of fracture risk, going beyond just bone mineral density (BMD) testing.
Who is the FRAX Score For?
FRAX is intended for specific groups to ensure its accuracy:
- Postmenopausal women and men aged 50 and older. It's validated for individuals up to 90 years old.
- Individuals diagnosed with osteopenia, which is low bone density (T-score between -1.0 and -2.5 on a DXA scan). FRAX helps determine if medication is needed for these individuals.
- Those who have not yet started medication for osteoporosis.
Key Inputs for the FRAX Calculation
The FRAX tool considers demographic information and clinical risk factors. These include:
- Age and Sex
- Weight and Height (for BMI)
- Previous Fracture
- Parental History of Hip Fracture
- Current Smoking
- Glucocorticoid Use (long-term steroid use)
- Rheumatoid Arthritis (RA)
- Secondary Osteoporosis (other bone loss conditions)
- Alcohol Consumption (high intake)
- Femoral Neck BMD (optional, but improves accuracy)
When the FRAX Score is Most Valuable
The FRAX score is most useful for guiding treatment decisions in individuals with osteopenia. While a DXA scan identifies low bone density, FRAX helps determine which patients with osteopenia have a high enough fracture risk to benefit from medication. For example, guidelines suggest considering treatment for those with osteopenia if their 10-year hip fracture risk is 3% or higher, or their major osteoporotic fracture risk is 20% or higher. This helps personalize care, ensuring treatment goes to those most in need.
FRAX vs. Other Bone Density Tools
FRAX complements, but does not replace, a DXA scan. Here's a comparison:
| Feature | DXA Scan | FRAX Score |
|---|---|---|
| What it measures | Bone mineral density (BMD). | 10-year probability of major osteoporotic fracture. |
| Data Input | Imaging. | Clinical risk factors and BMD (optional). |
| Result | T-score/Z-score. | Percentage of fracture probability. |
| Primary Use | Diagnose osteoporosis/osteopenia. | Guide treatment for osteopenia. |
| Limitations | Doesn't include clinical risk factors. | Doesn't include all risk factors (e.g., falls). |
Limitations and Considerations
FRAX has limitations that clinicians must consider:
- Binary Inputs: Risk factors are often yes/no, not accounting for severity (e.g., how much a person smokes).
- Missing Factors: It doesn't include falls, some medical conditions like diabetes, or the impact of multiple prior fractures.
- Static Risk: The calculation doesn't reflect that fracture risk is highest right after a fracture.
- Untreated Patients: Only for those not on osteoporosis medication.
- Limited BMD Data: Only uses femoral neck BMD, potentially missing issues in the spine.
How to Interpret Your FRAX Score
Your healthcare provider will calculate your 10-year probability of a hip fracture and a major osteoporotic fracture. These percentages are considered alongside your DXA results and other health information.
Risk Thresholds
General guidelines suggest high risk at:
- ≥3% for a hip fracture.
- ≥20% for a major osteoporotic fracture.
Exceeding these thresholds for individuals with osteopenia often leads to a discussion about medication to lower fracture risk. However, these are guidelines, and your doctor makes the final decision based on your overall health.
The Importance of Patient-Clinician Dialogue
A discussion with your doctor is vital to consider all your risk factors, including those not in the FRAX tool like falls. This ensures a personalized bone health plan. You can find resources from the Bone Health and Osteoporosis Foundation: Bone Health & Osteoporosis Foundation
The Takeaway for Proactive Senior Care
FRAX is a valuable tool in managing bone health for older adults. By identifying high-risk individuals with osteopenia, it supports informed decisions about preventive treatment. While imperfect, understanding when should FRAX score be used leads to more tailored care, helping to reduce fractures and improve the quality of life for seniors.
