The WHO Fracture Risk Calculator, also known as FRAX, is a tool developed by the World Health Organization to evaluate the 10-year probability of bone fractures based on individual patient profiles. This tool is specifically designed to estimate the risk of osteoporotic fracture in men and women based on clinical risk factors with or without Bone Mineral Density (BMD) values. It is particularly useful in the management of osteoporosis as it helps healthcare providers decide when to initiate treatment such as calcium, vitamin D supplementation, or more potent osteoporosis medications.
The FRAX tool requires input of several key pieces of information including age, sex, weight, height, and various clinical factors like previous fractures, parent fractured hip, current smoking, glucocorticoids use, rheumatoid arthritis, secondary osteoporosis, and alcohol consumption. Additionally, if available, the bone mineral density at the femoral neck can be included to enhance the accuracy of the risk assessment. Each of these factors is associated with specific risks of fracture and the FRAX algorithm calculates the probability of having a hip fracture or a major osteoporotic fracture within the next 10 years.
Interpreting the results from the WHO Fracture Risk Calculator involves understanding the percentage risk of fracture:
- Low risk (less than 10% fracture probability): Suggests minimal intervention aside from lifestyle modifications and possibly dietary supplementation.
- Moderate risk (10-20% fracture probability): May necessitate further investigation with bone density scans and possibly the initiation of osteoporosis medication.
- High risk (greater than 20% fracture probability): Typically calls for more aggressive treatment strategies to manage osteoporosis and prevent fractures.
These risk thresholds help guide clinical decisions, tailoring interventions to individual patient needs and helping to prevent fractures effectively, particularly in populations at increased risk due to age or underlying health conditions. Regular use of the FRAX calculator in clinical practice can help monitor risk over time, especially important for aging patients or those experiencing changes in health status that could affect their fracture risk.
