[FRAX® thresholds to identify people with high or low risk of osteoporotic fracture in Spanish female population].

Abstract Background and objective To detect FRAX ® threshold levels that identify groups of the population that are at high/low risk of osteoporotic fracture in the Spanish female population using a cost-effective assessment. Patients and methods This is a cohort study. Eight hundred and sixteen women 40–90 years old selected from the FRIDEX cohort with densitometry and risk factors for fracture at baseline who received no treatment for osteoporosis during the 10 year follow-up period and were stratified into 3 groups/levels of fracture risk (low 20%) according to the real fracture incidence. Results The thresholds of FRAX ® baseline for major osteoporotic fracture were: low risk dual energy X-ray absorptiometry (DXA-scan) for FRAX ®  ≥ 5 (Intermediate and high risk) to reclassify by FRAX ® with DXA-scan at high/low risk. These thresholds select 17.5% of women for DXA-scan and 10% for treatment. With these thresholds of FRAX ® , compared with the strategy of opportunistic case finding isolated risk factors, would improve the predictive parameters and reduce 82.5% the DXA-scan, 35.4% osteoporosis prescriptions and 28.7% cost to detect the same number of women who suffer fractures. Conclusions The use of FRAX ® thresholds identified as high/low risk of osteoporotic fracture in this calibration (FRIDEX model) improve predictive parameters in Spanish women and in a more cost-effective than the traditional model based on the T-score ≤ −2.5 of DXA scan.