Background World Health Organization developed a fracture risk assessment tool, named FRAX1. FRAX is a computer-based algorithm (http://www.shef.ac.uk/FRAX) that provides an estimate of fracture probability in men and women over the subsequent ten years1. Since osteoporotic fracture rates vary greatly between countries, the FRAX algorithm is calibrated to the target population3.
Objectives The objective of this study was to develop a Portuguese version of the World Health Organization (WHO) fracture risk assessment tool (FRAX®).
Methods Age- and sex-stratified cases of hip fracture in patients aged 40 years of age or more were extractedfrom the Portuguese National Hospital Discharge Registerdata from 2006 to 2010. Age and sex- ranked population estimates and mortality rates were provided by the Portuguese Institute for National Statistics. Incidences were computed for each year in intervals of five years and the average of the five years under consideration was taken. Given the lack of reliable data regarding other major fractures in Portugal, rates for these were imputed from the epidemiology of Sweden as undertaken for the majority of FRAX® models. All the methodological aspects and results were submitted to critical appraisal by a wide panel of national experts and representatives of the different stakeholders, including patients, to enhance data quality assurance and foster the adoption of the tool.
Results Hip fracture incidence rates were higher in women than in men and increased with age. The lowest incidence was observed in 40-44 years group (14.1 and 4.0 per 100,000 inhabitants for men and women, respectively). The highest rate was observed among the 95-100 age-group (2,577.6 and 3,551.8/100,000 inhabitants, for men and women, respectively).
The estimated ten-year probability for major osteoporotic fracture or hip fracture increased with decreasing T-score and with increasing age. Portugal has one of the lowest fracture incidences among European countries, which was, reflected in the estimated 10-year probability for major osteoporotic fracture or hip fracture. All stakeholders involved in this project officially endorsed the Portuguese FRAX® model and co-authored this paper
Conclusions The FRAX® tool can be used to estimate the ten-year risk of osteoporotic fractures. and applied to investigate the most appropriate intervention thresholds in Portugal. This is the first fracture prediction model that has been calibrated to the Portuguese population, using national data. Despite some limitationsof the FRAX® tool, its strengths and overall advantages are recognized worldwide. These qualities and the wide consensus obtained about its development and structure make the Portuguese FRAX® a good tool for implementation in clinical practice.
Kanis JA, Johnell O, Odén A, Johansson H, McCloskey E (2008) FRAX and the assessment of fracture probability in men and women from the UK. Osteoporos Int19:385– 397.
Kanis JA, Johnell O, De Laet C, Jonsson B, Odén A, Ogelsby AK (2002) International variations in hip fracture probabilities: implications for risk assessment. J Bone Miner Res17:1237– 1244.
Disclosure of Interest None Declared