[FRAX: a new instrument for calculating 10-year absolute fracture risk]

The efficacy of new pharmacological agents for the prevention of osteoporotic fractures and the clinical decision to intervene with that purpose in daily medical practice have been guided by the evaluation of bone mineral density (BMD). However, given the multifactorial nature of the proposed endpoint, a new calculator has been proposed: Fracture Risk Assessment Tool FRAX, which follows the same objectives of previous models, but integrates and combines several of those factors according to their relative weight. It can estimate absolute risk of hip fracture (or a combination of osteoporotic fractures) for the following 10 years. The calculator could be adapted for use in any country by the incorporation of hip fracture incidence and age- and sex-adjusted life expectancy in the same country. This instrument has been presented as a new paradigm to assist in clinical and therapeutic decision-making. In the present review some of its characteristics are discussed, such as: the purported applicability to different populations, the convenience of using 10-year absolute fracture risk for the whole age range under consideration, and whether the efficacy of pharmacological treatment for the prevention of bone fractures in osteoporotic patients can be expected to be equally effective among patients selected for treatment on the basis of this model. Finally, we would like to call attention to the fact that risk thresholds for intervention are not yet clearly defined; those thresholds can obviously be expected to have a profound impact on the number of patients amenable to treatment.