Comparison of hip fracture and osteoporosis medication prescription rates across Canadian provinces.

UNLABELLED: The study explores osteoporosis medication prescribing across Canadian provinces and any impact on hip fracture rates. Despite a marked variation in the prescribing of such medication, there is no effect on the hip fracture rate in either gender or any age group, suggesting either poor targeting or lack of efficacy.
INTRODUCTION: Hip fractures are the most disabling and costly of osteoporotic fractures, and a reduction in the risk of hip fracture is an expectation of osteoporosis medications. In this study, we have compared the use of osteoporosis medication across Canadian provinces with the rate of hip fractures in the same regions.
METHODS: Three years of hip fracture data (2007-2009 inclusive) were obtained from the Canadian Institute for Health Information for all Canadian provinces excluding Quebec. Population information was obtained from Statistics Canada and medication information from the Brogan Inc. database. Because osteoporosis medication is available daily, weekly, monthly, and yearly, medication prescriptions were converted to "units" of prescribing, so that a once a year infusion represented 365 units, a monthly prescription 30 units, and so forth.
RESULTS: There is a fourfold difference in prescribing across provinces but no corresponding variation in hip fracture rate. No significant correlation exists between prescribing load and hip fracture rate. This was true for all age groups, both genders, and for both intertrochanteric and subcapital hip fracture.
CONCLUSIONS: We find no association between osteoporosis medication prescribing and hip fracture rate. Possible explanations include insufficient numbers of at-risk patients on treatment, inappropriate targeting, and either lack of efficacy or efficacy limited to only certain subgroups of patients such as those with demonstrable trabecular osteoporosis.