The relationship between bone mineral density and ultrasound in postmenopausal and osteoporotic women

The aim of this cross-sectional study was to use a novel method of data ana lysis to demonstrate that patients with osteoporosis have significantly low er ultrasound results in the heel after correcting for the effect of bone m ineral density (BMD) measured in the spine or hip. Three groups of patients were studied: healthy early postmenopausal women, within 3 years of the me nopause (n = 104, 50%), healthy late postmenopausal women, more than 10 yea rs from the menopause (n = 75, 36%), and a group of women with osteoporosis as defined by WHO criteria (n = 30, 14%). Broadband ultrasound attenuation (BUA), speed of sound (SOS) and Stiffness were measured using a Lunar Achi lles heel machine, and BMD of the lumbar spine and left hip was measured us ing dual-energy X-ray absorptiometry (DXA). SOS, BUA and Stiffness were reg ressed against lumbar spine BMD and femoral BMD for all three groups combin ed. The correlation coefficients were in the range 0.52-0.58, in agreement with previously published work. Using a calculated ratio R, analysis of var iance demonstrated that the ratio was significantly higher in the osteoporo tic group compared with the other two groups. This implied that heel ultras ound values are proportionately lower in the osteoporotic group compared wi th the other two groups for an equivalent value of lumbar spine and femoral neck BMD. We conclude that postmenopausal bone loss is not associated with different ultasound values once lumbar spine or femoral neck BMD is taken into account. Ultrasound does not give additional information about pattern s of bone loss in postmenopausal patients but is important in those patient s with osteoporosis and fractures.