Correlation of quantitative ultrasound parameters of the calcaneus with bone density of the spine and hip in women with prevalent hypovitaminosis D.

Abstract

Quantitative ultrasound (QUS) of the calcaneus correlates modestly with axial dual-energy X-ray absorptiometry (DXA). Because bone mineral density (BMD) might be influenced by vitamin D status, we assessed the correlation between both techniques in 56 Arabian women, a population with high prevalence of hypovitaminosis D. The speed of sound (SOS), broadband ultrasound attenuation (BUA), and estimated BMD of the right calcaneus were determined by QUS. Spine and right hip BMD were measured by DXA scan. The serum 25-hydroxyvitamin D (25OHD) level was measured by radioimmunoassay. The correlations of QUS parameters (estimated calcaneal BMD, BUA, and SOS) with spine and hip BMD were modest (r = 0.50, r = 0.53, r = 0.41 for the spine and r = 0.54, r = 0.56, and r = 0.46 for the hip, respectively; p < 0.01 for all comparisons), but stronger in postmenopausal women. All postmenopausal women with low estimated calcaneal BMD (T-score pound -1) had a T-score pound -1 by DXA of the spine or hip. Of the 21 premenopausal women with spine or hip T-score pound -1 who had 25OHD measurements, 20 (95.2%) had levels below 50 nmol/L and 12 (57%) had levels below 30 nmol/L. The subgroup with 25OHD < 30 nmol/L had significantly lower spine (p < 0.01) and hip BMD (p < 0.05) than the subgroup with 25OHD >/= 30 nmol/L. QUS parameters were not significantly different between the two subgroups. The QUS and DXA correlated modestly well in women with prevalent hypovitaminosis D. QUS could be used in postmenopausal women with hypovitaminosis D to identify those at risk for osteoporotic fracture.