Australian FRAX tool; Fracture Risk Assessment Tool
BMI; BMI calculator
Fracture risk assessment using bone mineral density (BMD) is a crucial tool for predicting the likelihood of bone fractures, particularly in individuals with osteoporosis or low bone density. The assessment typically involves:
BMD Measurement (via DXA Scan)
- T-score: The most common way to assess BMD. It compares an individual's bone density to the average peak bone density of a healthy young adult. The T-score is expressed as a standard deviation (SD), how many SD away from the mean.
- T-score ≥ -1.0: Normal bone density
- T-score between -1.0 and -2.5: Osteopenia (low bone density, at risk for osteoporosis)
- T-score ≤ -2.5: Osteoporosis (high fracture risk)
Fracture Risk Factors
- In addition to BMD, several factors are used to assess fracture risk:
- Age: Older individuals are at higher risk.
- Gender: Women, especially postmenopausal, are at greater risk due to lower estrogen levels.
- Previous Fractures: A history of fractures increases future risk.
- Family History of Osteoporosis: Genetic predisposition can raise risk.
- Lifestyle Factors: Smoking, alcohol use, poor diet, and lack of exercise contribute to lower BMD.
- Medical Conditions: Conditions like rheumatoid arthritis, hormone disorders, and use of certain medications (like steroids) increase risk.
FRAX Tool
The FRAX tool; Fracture Risk Assessment Tool is a commonly used calculator that integrates BMD (T-score) and other clinical risk factors to estimate the 10-year probability of a major osteoporotic fracture (spine, forearm, hip, or shoulder) and hip fracture. It is widely used in clinical practice to guide treatment decisions.
Interpretation
- Low Risk: Minor risk factors and a normal or near-normal BMD.
- Moderate Risk: Osteopenia with some risk factors.
- High Risk: Osteoporosis with multiple risk factors or prior fractures.
Bone density combined with clinical risk factors provides a comprehensive picture of fracture risk, guiding treatment plans to prevent fractures.