Diagnostic value of quantitative ultrasound and Osteoporosis self-assessment tool in comparison with DXA in detecting low bone mineral density in post-menopausal women in Riyadh, Kingdom of Saudi Arabia

The objective of this study was to assess the diagnostic value of quantitative ultrasound (QUS) and Osteoporosis self-assessment tool (OST) compared with Dual Energy x-ray absorptiometry (DXA), and to identify the best cut-off value for determining low bone mineral density (BMD) among postmenopausal women in Riyadh, Saudi Arabia. We conducted a community based cross-sectional study on 224 randomly selected post-menopausal women. Women visited primary heath care centers for answering self-administered questionnaireand screening for low BMD using QUS technique. OST was calculated based on age and weight. DXA scanwas performedforlumbar spine and femur neck at King Khalid University Hospital, Riyadh. Mean age of participants was 58.05(±8.97) years. The prevalence of low BMD at lumbar spine and femur neck was 56% and 28% respectively. The best cut-off value for QUS and OST was ≤-1 and ≤2 respectively. QUS yielded sensitivity and specificity of 73% vs 47% for lumbar spine (area under curve (AUC) 0.56) and 84% vs 43% for femur neck (AUC 0.61). OST yielded sensitivity and specificity of 38% vs 84% for lumbar spine (AUC 0.62) and 48% vs 78% for femur neck (AUC 0.68). On combining the results, sensitivity and specificity were81% vs 41% (AUC 0.61) for lumbar spine and 89% vs 35% for femur neck (AUC 0.68) respectively. QUS and OST separately have limited diagnostic value, however on combining both instruments there is improvement in sensitivity to detect low BMD for both lumbar spine and femur neck.

Keywords: diagnostic value, screening tools, quantitative ultrasound, osteoporosis self-assessment tool, DXA