Although some guidelines recommend use of bisphosphonates for men on androgen deprivation therapy (ADT), a study published in the December 3, 2014, JAMA reports that prescriptions for these drugs remain low, even for those men at high risk of subsequent fractures.
“Although the optimal rate of bisphosphonate use in men on ADT is unknown, it is reasonable that most men with prior osteoporosis or fracture should be taking a bisphosphonate or other effective bone medication,” stated Husayn Gulamhusein, BHSc, of the University Health Network in Toronto, and his research colleagues.
Using administrative databases at the Institute for Clinical Evaluative Sciences and the Ontario Cancer Registry, Mr. Gulamhusein and his team examined rates of bisphosphonate prescriptions in men initiating ADT in Ontario between 1995 and 2012. The study group included men ages 66 or older who were starting ADT for prostate cancer, who had undergone surgical removal of one or both testicles, or who received at least 6 months of continuous medical ADT and survived at least one year after ADT initiation.
Bisphosphonate claims within 12 months of ADT initiation were captured through drug database claims. Bisphosphonate prescription was examined for three groups: all nonusers of bisphosphonates, those with prior osteoporosis, and those with prior fragility fracture.
A total of 35,487 men with prostate cancer who began ADT during the study period were identified. Bisphosphonate claims among all nonusers increased from 0.35 per 100 persons in 1995 to 1997 to 3.40 per 100 persons in 2010 to 2012. Rates remained low, even among those with prior osteoporosis or fragility fracture. Among all three groups, peak bisphosphonate claims occurred between 2007 to 2009, with a high of 11.89 per 100 persons in those with prior osteoporosis.
Mr. Gulamhusein and his research team speculate that the decrease in bisphosphonate prescriptions after 2009 may be partly due to recent negative media attention regarding the association of bisphosphonates with rare osteonecrosis of the jaw and atypical femoral fractures. “This is appropriate for groups at low risk for fractures, but the decrease in use for high-risk patients is troubling,” the study authors wrote.