Multisite quantitative ultrasound: Precision, age- and menopause-related changes, fracture discrimination, and T-score equivalence with dual-energy X-ray absorptiometry

This study evaluated the clinical utility of a new multisite ultrasound dev ice capable of measuring speed of sound (SOS) at the phalanx, radius, tibia and metatarsal. The in vitro and in vivo short- and long-term precision we re evaluated, reference data were collected for 409 healthy white women (23 6 premenopausal and 173 postmenopausal), and age and menopause related chan ges were calculated using linear regression. Fracture discrimination was ev aluated using 109 women with vertebral fractures and the age-adjusted odds ratios calculated for each standard deviation decrease in SOS measurement. Correlations between SOS measurements and spine and femur bone mineral dens ity (BMD) were calculated. T-score equivalence with BMD was also investigat ed together with the prevalence of osteoporosis as defined by the WHO crite ria. The in vivo short-term precision standardized in T-score units ranged from 0.14 to 0.33 and long-term standardized precision was 0.35-0.65. Postm enopausal age-related bone loss expressed as the annual change in T-score r anged from 0.040 to 0.089 for SOS and 0.053 to 0.066 for BMD, whilst menopa use-related annual loss ranged from 0.036 to 0.094 for SOS and 0.050 to 0.0 74 for BMD. Correlations between the different SOS sites ranged from r = 0. 24 to 0.55, and between SOS and BMD from r = 0.12 to 0.47. The odds ratio ( and 95% confidence intervals) for fracture per 1 SD decrease in SOS were 2. 0 (1.22 to 3.23) for the phalanx; 1.5 (1.01 to 2.24) for the metatarsal; 1. 4 (1.03 to 1.99) for the radius and 1.2 (0.87 to 1.66) for the tibia. Odds ratios for BMD in the same population ranged from 2.6 to 4.8 (1.70 to 8.29) . The prevalence of osteoporosis as defined by T = <-2.5 in the age range 6 0-69 ranged from 7.1% to 20.6% for SOS and 6.4% to 12.1% for BMD. In conclu sion, this study demonstrated that multisite ultrasound has adequate precis ion for investigating skeletal status, is capable of differentiating betwee n pre- and postmenopausal women and women with vertebral fractures, has a T -score equivalence similar to that of dual-energy X-ray absorptiometry (DXA ), and appears to be a promising new technique for evaluating skeletal stat us at clinically relevant sites.