Much has changed in these years about therapy for osteoporosis: new drugs have been introduced; we have more information about fracture risk and osteoporosis in not only in men but also in non white women; about the use of estrogen therapy. It is also important to underline that now a large number of people, especially women, knows the importance to prevent osteoporosis and the important to do radiological and biochemical exams to control the bone mineral density. Actually there is the practice guide from the National Osteoporosis Foundation (NOF) that makes recommendations for the management of patients with specific clinical presentations (www.nof.org/physguide/index.htm). Recently the World Health Organization (WHO) has introduced a new fracture prediction algorithm (FRAX-TM) to determine a patient’s absolute (%), as opposed to relative, fracture risk (Osteoporos Int DOI 10.1007/s00198-007-0543-5). All new guidelines and algorithms are important and show new elements to improve clinical management of the pathology, but they are linked to the economic aspect of this management. NOF has completed an updated economic analysis, which suggests that osteoporosis treatment would generally be cost-effective in patients with a 10-year hip fracture probability of around 3% (Osteoporos Int DOI 10.1007/s00198-007-0550-6). The aim of this report is to evaluate the effect of this new approach to risk assessment in the context of a revision of the NOF practice guidelines. The WHO fracture prediction algorithm has been calibrated to the US population using national age, sex and race specific death rates and age and sex specific hip fracture incidence rates from the largely white population of Olmsted County. The WHO algorithm estimated the probability of a hip fracture over 10 years, given specific age, gender, race and clinical profiles. The combined cohort comprised over 60.000 subjects, who were followed for a quarter of a million person-years; 5.563 fractures were observed during follow up, including 978 hip fractures. The risk factors were: age, femoral neck BMD, body mass index, personal history of prior fragility fracture, rheumatoid arthritis, secondary causes of osteoporosis (inflammatory bowel disease), parental history of hip fracture, long term (3 months or more) exposure to systemic corticosteroids, high alcohol intake, cigarette smoking. The WHO fracture prediction algorithm is applied by assuming that the interrelations among the clinical risk factors and hip BMD with respect to fracture risk are constant across populations. It is cost-effective to treat patients with a fragility fracture and those with osteoporosis by WHO criteria, as well as older individuals at average risk and osteopenic patients with additional risk factors. The estimated 10-year fracture probability was lower in men and non white women compared to postmenopausal white women. In particularly patients who present a fracture generally have a future 10-year hip fracture probability high enough to warrant treatment and future fracture risk is lower in non white than white women and men who present with a prior fracture. This report underlines that existing clinical recommendations will need to change very little, because the WHO algorithm includes many of the same risk factors used in the original NOF analysis (age, femoral neck BMD, weight, personal fracture history, family history of fracture, cigarette use) even if new ones have been added (race, gender, corticosteroid use, history of secondary osteoporosis). This report shows that treatment appear to be justified economically as well clinically for patients who present with fractures and those with osteoporosis. There is less agreement about what to do for patients with low bone mass or osteopenia. It is important to underline that a patient’s estimated fracture can not be the sole basis for treatment decision. Specific treatment decisions must be individualized and an estimate of the patient’s 10-year fracture risk should facilitate shared decision-making.

Posted by: Alberto Lombardi, Fondazione Giovanni Lorenzini (Milan – Houston)

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