Fracture Risk Score and Absolute Risk of Fracture
Radiology: Volume 259: Number 2-May 2011
Margaret J. Henry, BSc (Hons), PhD Julie A. Pasco, BSc (Hons), Dip Ed, PhD, M Epi Elizabeth N. Merriman, BSc (Hons) Yu Zhang, BSc (Hons) Kerrie M. Sanders, BSc, G Dip Diet, M H Nutr, G Cert Hlth Econ, PhD Mark A. Kotowicz, MBBS, FRACP Geoffrey C. Nicholson, MBBS, PhD, FRACP, FRCP
Purpose: To report the 5- and 10-year absolute risk of fracture associated with the previously reported fracture risk (FRISK) score.
Materials and Methods: All participants gave written, informed consent, and the Rarwon Health Human Research Ethics Committee approved the study. An age-stratified population-based sample of women aged 60 years and older (n = 600) was recruited during 1994-1996. FRISK scores of 0-10 incorporating bone mineral density (RMD) at two sites (hip and spine), falls scores in the previous 12 months of 1-4, weight, and number of fractures as an adult were calculated. Fractures of the hip, spine, humerus, and wrist were ascertained during a median follow-up period of 9.6 years (interquartile range, 6.6-10.5). The cumulative probability of fracture at 5 and 10 years after baseline measurements was calculated by using actuarial methods. The utility of this model was compared with other FRISK algorithms, including the World Health Organization FRISK assessment tool FRAX designed for United Kingdom and that designed for the United States and the Garvan nomogram (Australia).
Results: This study supplies the 5- and 10-year absolute risk of fracture associated with all levels of the FRISK score. While there are modest differences in absolute risk of fracture seen for different numbers of prior fractures, the more marked differences occur across the different categories of falls scores and different categories of RMD. The receiver operating characteristic curves showed no significant difference in area under the curve for all four absolute risk of fracture algorithms.
Conclusion: Absolute risk of fracture can be determined by using readily obtainable clinical information that may aid treatment decisions.