Study: WHO FRAX underestimates risk of fragility fractures

The World Health Organization’s fracture risk assessment tool underestimates the risk of fragility fracture among individuals younger than 65 years or those who have been treated for a single fracture, according to results published in the Journal of Clinical Endocrinology and Metabolism.

“Although FRAX [fracture risk assessment tool] is a helpful tool and provides important information, it should not be used as the unique and definitive gold standard for determining whether or not to treat a patient for osteoporosis or weakening bones,” study researcher Gilles Boire, MD, MSc, of the division of rheumatology at the University of Sherbrooke, in Quebec, Canada, stated in a press release from The Endocrine Society. “The test fails to identify some patients who would benefit from treatment to prevent future fractures.”

Using the Canadian FRAX, Boire and colleagues gauged the fracture risk of 1,399 patients older than 50 years who were identified with fragility fractures between June 2007 and May 2012. Researchers calculated FRAX scores without bone mineral density prior to and after the inclusion fragility fracture and recorded recurrent fragility fractures during a 4 year follow-up. Univariate and multivariate analyses determined the determinants associated with recurrent fragility fractures.

Before experiencing a fragility fracture, 42.7% of patients were at high-risk for fracture vs. 56.4% after an incident fragility fracture. Results showed men, patients younger than 65 years or those without a previous fragility fracture had a low or moderate risk before their initial fragility fracture. According to study results, recurrent fragility fracture occurred in 108 patients during a median follow-up of 3 years. Researchers found the overall sensitivity of post- fragility fracture FRAX to predict a recurrent fragility fracture was 71.3%. FRAX prediction of recurrent fragility fracture was lower in patients younger than 65 years and in those without previous fragility fracture at inclusion.

“A bone fracture occurring after no or minimal trauma in people older than 50 [years] — i.e., a fragility fracture — is one of the strongest predictors of subsequent fractures,” Boire told Orthopedics Today. “Incident fragility fractures, and even more so recurrent fragility fractures, are associated with long-term disability an increased mortality. Identifying individual patients at high risk for incident and recurrent fractures would allow for more timely and targeted prevention.”

References:

Roux S. J Clin Endocrinol Metab. 2014;doi: 10.1210/jc.2013-4507.

www.endocrine.org.

Disclosure: Boire received lecture fees or advisory board fees from Merck Canada, Procter&Gamble Canada, sanofi-aventis Canada, Amgen Canada and Novartis Canada Inc.