Bisphosphonates and Fractures

Bisphosphonates may increase rare fracture risk.
The Wall Street Journal (5/5, Marcus, Subscription Publication) reports that, according to a study published in the New England Journal of Medicine, the use of bisphosphonates increase the risk rare fractures of the thigh bone.
HealthDay (5/4, Reinberg) reported that, for the study, Dr. Per Aspenberg, of Linköping University in Sweden, and colleagues, "collected data on 12,777 women, aged 55 and older, who had fractured femurs in 2008. Among these women, they identified 59 with atypical fractures." The researchers "used data from registries to estimate the use of bisphosphonates. In addition, they compared the 59 cases of atypical fractures with 263 women who had typical fractures."
MedPage Today (5/4, Gever) reported, "Whereas the rate of atypical subtrochanteric femoral fractures in the general population of older Swedish women not using bisphosphonates was 0.09 per 10,000 person-years, it was 5.5 per 10,000 person-years among those who did take the drugs (age-adjusted relative risk 47.3, 95% CI 25.6 to 87.3)."
WebMD (5/4, Doheny) reported that duration of use "affected risk." For every "100 days of bisphosphonate use, the risk of the unusual fracture rose by 30%" but the risks "declined quickly after the drug was stopped." The risk was "reduced by 70% per year since the last use of the drug"; and for "one unusual fracture to occur, 2,000 women had to take the bisphosphonate drugs for one year."