PHILADELPHIA — Antiresorptive therapy reduces the risk of recurrent hip fracture by more than 25%, according to one analysis presented at the annual meeting of the American Society for Bone and Mineral Research.
Patients exposed to bisphosphonate therapy following a first hip fracture had a 26% reduction in recurrent hip fracture (hazard ratio [HR] 0.74), after adjusting for age, sex, comorbidity, and medication, said Dr. Suzanne N. Morin, an internist at the McGill University Health Centre in Montreal.
Dr. Morin and her colleagues performed a retrospective cohort study, using administrative databases to identify patients aged 65 years and older who had been hospitalized for a first hip fracture between 1996 and 2003.
A total of 20,644 patients were identified and classified based on whether they had been exposed to antiresorptive therapy following hospital discharge for hip fracture. Exposure was defined as being dispensed a prescription for bisphosphonates, raloxifene, calcitonin, or hormone replacement therapy.
Of those patients, 6,779 were exposed to antiresorptive therapy (mean time to first exposure after hospital discharge was 3 months) and 13,865 were not. Most of the patients—90% of those exposed and 73% of those not exposed—were women.
“In general, the exposed patients tended to be younger and to have less comorbidities than the nonexposed,” Dr. Morin said. The antiresorptive-exposed patients were also more likely to take calcium and vitamin D supplements and to use corticosteroids. Bisphosphonates were prescribed the most frequently.
For exposed patients, follow-up began on the day that the prescription for an antiresorptive was filled. Unexposed patients were assigned starting dates that were frequency matched to those of the exposed patients. Mean follow-up was 2.2 years, during which time 9,146 patients died and 992 recurrent fractures occurred. The refracture rate was 2.2 per 100 person-years for the exposed group and 2.9 per 100 person-years for the nonexposed group.
Men were also less likely to have a recurrent hip fracture (HR 0.75). For each 1-year increase in age, the risk increased 3%. The presence of osteoporosis was associated with a twofold increase in the risk of recurrent hip fracture.