Evaluation of clinical risk factors for osteoporosis and applicability of the FRAX tool in Joinville City, southern Brazil

Summary Clinical risk factors for fracture in Southern Brazil are similar to those used in Fracture Risk Assessment Tool (FRAX®). Age-dependent intervention thresholds had higher accuracy than a fixed cut-off point. Introduction Access to bone mineral density testing is wanted for a large part of the Brazilian population. The FRAX® has an option to calculate the risk of fracture without this costly evaluation but relies on the clinical risk factors (CRFs) identified in the source cohorts used to generate FRAX. Objective The aims of this study were to determine whether the CRFs used in FRAX are also risk indicators for individuals in Southern Brazil and to evaluate possible intervention thresholds for treatment in Brazil. Methods We determined the CRFs for hip fractures in women and men aged 50 years and more with a hip fracture and controls in Joinville, Southern Brazil (April 1, 2010, and March 31, 2012). For intervention thresholds, we determined the accuracy of using the fixed thresholds of National Osteoporosis Foundation (NOF), USA, compared with the age-dependent thresholds of the National Osteoporosis Guideline Group (NOGG), UK. Results CRFs that were significant for hip fracture were very similar to FRAX, apart from chronic obstructive pulmonary disease and malabsorptive intestinal disease. FRAX based on the NOGG and NOF models had an accuracy of 64.2 and 58.7%, respectively. Conclusion CRFs used in FRAX® were similar to those in the Southern Brazil. The NOGG model seems to be more accurate to discriminate patients with increased fracture risk in this population compared to the NOF model, but not significantly.