Zoledronic acid reduces the rate of clinical fractures after surgical repair of a hip fracture regardless of the Pretreatment bone mineral density.

In patients with surgical repair of a low-trauma hip fracture, zoledronic acid (ZA) reduced the risk of subsequent fractures regardless of pretreatment femoral neck and total hip bone mineral density (BMD).
Introduction: Zoledronic acid reduces the risk of subsequent fractures after repair of a hip fracture. It is still unclear whether the benefits in fracture reduction with ZA depend upon hip bone mineral density at the time of fracture.
Methods: We preformed additional post hoc analyses of data from the HORIZON Recurrent Fracture Trial to determine if ZA treatment reduced the risk of new clinical fractures regardless of pretreatment BMD. We modeled femoral neck and total hip BMD as both continuous and dichotomous variables (BMD T-score above and below -2.5).
Results: There are no evidence that baseline femoral neck and total hip BMD modified the anti-fracture efficacy of ZA when pretreatment BMD was analyzed as a continuous or a dichotomous variable (interaction p-values > 0.20). The clinical fracture efficacy of ZA was similar among patients with pretreatment femoral neck BMD values above and below -2.5 (relative hazards = 0.60 and 0.67, respectively, interaction p-value = 0.95). A similar result was obtained using pretreatment total hip BMD values (relative hazards = 0.72 and 0.57, respectively, interaction p-value = 0.41).
Conclusion: There data should provide more comfort in prescribing ZA after surgical repair of a hip fracture, regardless of pretreatment BMD.