Clinical risk factors for osteoporosis in Ireland and the UK: a comparison of FRAX and QFracturescores

Introduction: Recently two algorithms have become available to estimate the 10-year probability of fracture in patients suspected to have osteoporosis on the basis of clinical risk factors (CRF); the FRAX algorithm and QFractureScores algorithm (QFracture). The aim of this study was to compare the performance of these algorithms in a study of fracture patients and controls recruited from six centres in the UK and Ireland. Methods: A total of 246 postmenopausal women aged 50-85 years who had recently suffered a low trauma fracture were enrolled and their characteristics were compared with 338 female controls who had never suffered a fracture. Measurements of femoral bone mineral density (BMD) were performed by dual energy X-ray absorptiometry (DXA) and fracture risk was calculated using the FRAX and QFracture algorithms. Results: The FRAX algorithm yielded higher calculated scores for fracture risk than the QFracture algorithm. Accordingly, the risk of major fracture in the overall study group was 9.5% for QFracture compared with 15.2% for FRAX. For hip fracture risk the values were 2.9% and 4.7% respectively. The correlation between FRAX and QFracture was R=0.803 for major fracture and R=0.857 for hip fracture (p≤0.0001). Both algorithms yielded high specificity but poor sensitivity for prediction of osteoporosis. Conclusions: We conclude that the FRAX and QFracture algorithms yield similar results in the estimation of fracture risk. Both of these tools could be of value in primary care to identify patients in the community at risk of osteoporosis and fragility fractures for further investigation and therapeutic intervention.