FRAX: A Fracture Risk Calculator

FRAX is a tool developed by the World Health Organization in 2008 to assess fracture risk. FRAX integrates clinical risk factors and bone mineral density (BMD) at the femoral neck to calculate a 10-year fracture probability for men and women.

Simply put, it's a fracture risk calculator. It can help a healthcare provider identify people who need intervention or treatment to lower that probability.

Development of the FRAX Calculator

The models used to develop the FRAX calculator were derived from studying patient populations in North America, Europe, Asia, and Australia. There are paper versions of FRAX available but a free online FRAX tool exists as well. The web version is available in various languages.​

According to Postgraduate Medicine, "Osteoporosis-related fractures (low-trauma or fragility fractures) cause substantial disability, healthcare costs, and mortality among postmenopausal women and older men.

Epidemiologic studies indicate that at least half the population burden of osteoporosis-related fractures affects persons with osteopenia (low bone density), who comprise a larger segment of the population than those with osteoporosis. The public health burden of fractures will fail to decrease unless the subset of patients with low bone density who are at increased risk for fracture are identified and treated."

Knowing your 10-year fracture probability allows you and your healthcare provider to make treatment decisions. The goal, if treatment is indicated, would be to lower your risk of bone fracture and to prevent osteoporosis. Because osteoporosis is a silent disease, meaning that no symptoms typically are apparent until a fracture occurs, lowering risk is essential.

The National Osteoporosis Foundation recommends treating patients with FRAX 10-year risk scores of 'greater than or equal to 3 percent' for hip fracture or 'greater than or equal to 20 percent' for a major osteoporotic fracture to reduce fracture risk.

The FRAX Questionnaire

FRAX asks 12 questions and then calculates your 10-year fracture probability. The information that is input to determine your fracture risk includes:

• Age or date of birth
• Male or female
• Weight in kilograms
• Height in centimeters
• Previous fracture (no or yes)
• Parent fractured hip (no or yes)
• Current smoking (no or yes)
• Glucocorticoids (no or yes)
• Rheumatoid arthritis (no or yes)
• Secondary osteoporosis (no or yes)
• Alcohol - 3 or more units per day (no or yes)
• Femoral neck bone mineral density - BMD in g/cm(squared)

The FRAX calculator asks very specific questions related to glucocorticoids, rheumatoid arthritis, secondary osteoporosis, and alcohol use.

To answer yes to the glucocorticoid question, you must have taken three months or more of prednisolone at 5 mg a day (or the equivalent dose of other steroids).

"Yes" for rheumatoid arthritis means you have a confirmed diagnosis. "Yes" to secondary osteoporosis means you have a condition that is strongly linked to osteoporosis.

Summary

The FRAX calculator determines the 10-year fracture probability for an individual. By doing so, the calculator identifies people who can benefit from intervention or treatment to lower that probability. A healthcare provider can then decide on further diagnostic testing and treatment.