BROAD-BAND ULTRASOUND ATTENUATION PREDICTS FRACTURES STRONGLY AND INDEPENDENTLY OF DENSITOMETRY IN OLDER WOMEN - A PROSPECTIVE-STUDY

Background: Quantitative ultrasound of bone is a new radiation-free te chnique that measures bone mass and may assess bone quality. Retrospec tive studies have suggested that low-bone ultrasound of the calcaneus is associated with an increased risk for hip and other fractures in ol der women. Objectives: To establish the utility of calcaneal quantitat ive ultrasound of bone for the prediction of fractures and to compare quantitative ultrasound of bone with bone mineral densitometry by perf orming a prospective cohort study within the Study of Osteoporotic Fra ctures. Subjects and Methods: We studied 6189 postmenopausal women old er than 65 years at 4 US clinical centers. Broadband ultrasound attenu ation (BUA), a measurement of the differential attenuation of sound wa ves transmitted through the calcaneus, and bone mineral density of the calcaneus and hip were measured. Subsequent hip and other nonspine fr actures were documented during a mean follow-up of 2.0 years. Results: In age- and clinic-adjusted analyses, each SD reduction in calcaneal BUA was associated with a doubling of the risk for hip fractures (rela tive risk [RR], 2.0; 95% confidence interval [CI], 1.5-2.7); a similar relationship was observed with bone mineral density of the calcaneus (RR, 2.2; 95% CI, 1.9-3.0) and femoral neck (RR, 2.6; 95%;, CI, 1.9-3. 8). After adjustment for bone mineral density of the femoral neck, BUA was still associated with an increased risk for hip fracture (RR, 1.5 ; 95% CI, 1.0-2.1). Intertrochanteric fractures in particular were str ongly associated with a low BUA measurement (RR, 3.3; 95% CI, 2.0-5.5) . Conclusions: Broadband ultrasound attenuation predicts the occurrenc e of fractures in older women and is a useful diagnostic test for oste oporosis. The strength of the association between BUA and fracture is similar to that observed with bone mineral density.