Zoledronic acid was effective for secondary prevention.
Patients who experience hip fractures have substantially increased risk for subsequent fractures, both at the hip and elsewhere. In this industry-sponsored randomized trial, researchers examined whether once-yearly IV zoledronic acid is effective for secondary prevention after hip fractures. This bisphosphonate drug (brand name, Reclast) was recently FDA-approved for postmenopausal osteoporosis based on results from a large randomized trial (Journal Watch May 2 2007).
More than 2000 patients received a yearly IV dose of zoledronic acid or placebo, starting within 90 days after surgically repaired hip fracture. Only patients unable or unwilling to take an oral bisphosphonate were enrolled. The trial was halted after an average follow-up of 2 years, when the rate of new fractures was significantly lower in the zoledronic acid group than in the placebo group (8.6% vs. 13.9%); reduction in both vertebral and nonvertebral fractures was noted. Mortality was also significantly lower in the zoledronic acid group (9.6% vs. 13.3%). No major adverse effects or detrimental effects on healing of the index hip fracture were reported.
Comment: This trial is the first to show that bisphosphonate therapy specifically after hip fracture prevents subsequent fractures. The authors do not precisely define which patients were "unable or unwilling to take an oral bisphosphonate" and thus qualified for inclusion in this trial; presumably, oral bisphosphonates would provide the same benefit. Also, the mechanism for the reduced mortality is unclear. Nonetheless, these results indicate that a yearly IV dose of zoledronic acid is a reasonable option after hip fracture. Note that the retail cost of a single dose — about US$1000 — is similar to that of a 1-year supply of daily, weekly, or monthly oral bisphosphonates.
Published in Journal Watch General Medicine October 25, 2007
Lyles KW et al. Zoledronic acid and clinical fractures and mortality after hip fracture. N Engl J Med 2007 Nov 1; 357;