Progress of osteoporosis: stratification of fracture risk

Background: There are two approaches to identify candidates for the prescription of osteoporosis treatment: identification of patients with low bone mineral density using DEXA of the axial skeleton and calculation of the 10-year probability of major osteoporotic fractures using FRAX®. Aims: to assess the diagnostic accuracy of different FRAX® thresholds in the Russian population. Materials and methods: the value of individual 10-year probability of osteoporotic fracture by FRAX® at the time of inclusion in the study was retrospectively estimated in 224 postmenopausal women, whom the major osteoporotic fractures were recorded over 10 years of prospective observation. The diagnostic accuracy of different thresholds were compared: "European" and Russian age-dependent thresholds, fixed 20% threshold, the average FRAX® of patients who had a major osteoporotic fracture during follow-up (16%), FRAX® value corresponding to the "cut-off point" (12,5%). Results: The Russian FRAX model showed the acceptable diagnostic accuracy of the method (AUC=0.665±0.036; 95% CI 0.595; 0.736). The "European" threshold of therapeutic intervention demonstrated 72% sensitivity and 38% specificity, 20% threshold – 27% and 87%, the Russian threshold – 41% and 77%, 12.5% threshold – 68% and 58%, 16% threshold – 57% and 73%, respectively. The diagnostic precision of the specified thresholds was 54%, 58%, 60%, 63% and 65%, respectively. Conclusions: the Russian age-dependent threshold remains the optimal way to decide whether to initiate anti-osteoporotic therapy based on an assessment of the 10-year probability of fracture by the Russian model for FRAX®.