Major Advances in Osteoporosis Assessment: New NOF Guidelines and the’s FRAX Risk-assessment Tool

Osteoporosis is a major public-health problem, with an estimated 44 million US residents at risk for fracture.¹ Much-needed direction can be provided by new guidelines from the National Osteoporosis Foundation (NOF) and the new FRAX® tool from the World Health Organization (WHO). Since there often are no warning signs before a fracture, improving the assessment of risk will prevent potentially debilitating consequences.

Older guidelines did not assess the effects of age, sex, history, genetic factors, and ethnicity on osteoporosis-related risk, but the updated NOF guidelines provide clearer direction. In addition, WHO’s FRAX tool uses an algorithm that determines the likelihood of fracture in the next 10 years. One of the most important factors is bone-mineral density (BMD), usually expressed as a T-score and determined using dual-energy x-ray absorptiometry. BMD alone, however, does not capture the full risk, since increased fracture risk may be present well before an osteoporotic T-score.²

New Guidelines and FRAX

The new NOF guidelines are the most clear and specific issued to date (Table 1). They include groups at high risk, such as older men; anyone with a possible osteoporosis-related fracture; and individuals with specific risk factors, such as age and history of fracture. They also include multiple ethnicities; previous guidelines addressed only white females.

The WHO’s new FRAX tool predicts the 10-year risk of both hip fracture and other major osteoporotic fractures (including spine and forearm fractures) in men and women. The tool is currently available online at www.shef.ac.uk/FRAX/. In addition to being available on the Web, FRAX is available as a convenient software option on some bone densitometers.

FRAX predicts 10-year fracture risk based on a patient’s BMD and risk factors (Table 2). The data are individualized based on sex; ethnicity (white, black, Asian, and Hispanic); and country of origin (the United Kingdom, France, Italy, Japan, Spain, Sweden, China, and Turkey). FRAX can make predictions based on clinical risk factors alone or in combination with BMD, but the combination will produce a better result than either would alone.

The FRAX tool makes its predictions using the largest collection of osteoporosis data ever assembled. WHO analyzed nine large prospective studies of more than 60,000 subjects worldwide; they had 5,563 fractures, including 978 involving the hip. The FRAX algorithm uses the identified risk factors in these populations to target the fracture risk for individuals with various characteristics.

Osteoporosis treatment is cost effective when the 10-year probability of hip fracture reaches 3% or more, or when the 10-year probability of a major osteoporosis-related fracture is greater than 20%. This economic analysis3 is based on a drug cost of $600 per year plus associated costs, as well as on estimates (specific to the United States) for fracture incidence, morbidity, mortality, cost of fracture treatment, and quality of life. Although knowing the fracture risk and recommended treatment facilitates decision making, physicians must evaluate each patient individually and decide, with their patients, whether treatment is appropriate.

Conclusion

With the use of the NOF guidelines and the new FRAX tool (either online or on the bone densitometer), the ability to evaluate and treat men and women of different ethnicities has been greatly enhanced. These advances should be used, in addition to clinical judgment, to make decisions regarding the proper treatment for individual patients. Knowing the new NOF guidelines and incorporating the FRAX tool into daily practice will improve the ability to detect (and begin treatment for) this widespread disease

References
1. National Osteoporosis Foundation. Clinician’s guide to prevention and treatment of osteoporosis. Available at: http://www.nof.org/professionals/cliniciansguide_form.asp. Accessed October 28, 2008.

2. Licatam A, Johnston C. Identifying postmenopausal women at risk for fracture. Female Patient. 2007;32:18-25.

3. Dawson-Hughes B, Tosteson ANA, Melton LJ 3rd, et al. Implications of absolute fracture risk assessment for osteoporosis practice guidelines in the USA. Osteoporos Int. 2008;19:449-458.