We lack effective diagnostics of osteoporosis at the primary health care level. An ultrasound device was used to identify subjects in the osteoporotic range as defined by DXA. A case finding strategy combining ultrasound results with DXA measurements for patients with intermediate ultrasound results is presented.
Introduction: We lack effective screening and diagnostics of osteoporosis at primary health care. In this study, a pulse-echo ultrasound (US) method is investigated for osteoporosis screening.
Methods: A total of 1091 Caucasian women (aged 50-80 years) were recruited for the study and measured with US in the tibia and radius. This method measures cortical thickness and provides an estimate of bone mineral density (BMD) and density index (DI). BMD assessment of the hip was available for 988 women. A total of 888 women had one or more risk factors for osteoporosis (OP susp ), and 100 women were classified healthy. Previously determined thresholds for the DI were evaluated for assessment of efficacy of the technique to detect hip BMD at osteoporotic range (T-score at or below - 2.5).
Results: In the OP susp group, the application of thresholds for the DI showed that approximately 32% of the subjects would require an additional DXA measurement. The multi-site ultrasound (US) measurement-based DI showed 93.7% sensitivity and 81.6% specificity, whereas the corresponding values for single-site US measurement-based DI were 84.7 and 82.0%, respectively. The ultrasound measurements showed a high negative predictive value 97.7 to 99.2% in every age decade examined (ages 50-59, 60-69, 70-79 years).
Conclusions: The study data demonstrate that a strategy of combining ultrasound measurement with added DXA measurements in cases with intermediate ultrasound results (about 30%) can be useful for identifying subjects at risk for a low bone mineral density in the osteoporotic range.
Keywords: Bone; DXA; Osteoporosis; Screening; Ultrasound.