Do age and bone density alone predict fracture risk as well as FRAX?

A simple model based on age and bone mineral density (BMD) alone may predict 10-year risk of hip, major osteoporotic, and any clinical fracture in older women as well as more complex fracture risk assessment tool (FRAX) models with BMD. In addition, a parsimonious model based on age and fracture history alone may predict 10-year risk of these fractures as well as more complex FRAX models without BMD.

Ensrud and associates used data from the Study of Osteoporotic Fractures to compare FRAX (with BMD) with simple models based on age and BMD alone for predicting fracture risk in 6252 older women. They performed a secondary analysis that compared FRAX (without BMD) with simple models based solely on age and fracture history.

The simple models were just as effective as FRAX in predicting 10-year fracture risk comparisons. The proportion of women who actually experienced a fracture was similar in the FRAX and the simple model groups.

The authors noted that both the FRAX models and the simple models are limited in their ability to predict fractures, especially nonhip fractures, making risk prediction a challenge, even when robust risk factors such as BMD and age are available.