MedicalResearch.com Interview with:
Shabbir M. H. Alibhai, MD, MSc and
Husayn Gulamhusein, BHSc
Department of Medicine, University Health Network
Toronto, Ontario, Canada
Medical Research: What is the background for this study? What are the main findings?
MedicalResearch: In 2009, we published a research letter in JAMA which examined the rate of bone mineral density (BMD) testing in men starting androgen deprivation therapy (ADT) in the province of Ontario, Canada, between 1995 and 2008. Despite being recommended as a tool to better characterize fracture risk and optimize bone health, use of bone mineral density testing was low throughout the study period. This current study focuses on another aspect of bone health, which is the use of bisphosphonates among men undergoing androgen deprivation therapy for prostate cancer. Bisphosphonates are generally safe and effective medications that can reduce fracture risk particularly in those at higher risk of future fracture. Throughout the 17-year study period, we found that rates of new prescriptions for bisphosphonates remained low. Even when focusing on those men who should be receiving bisphosphonates as per Canadian guidelines due to their high risk for future fracture, i.e. those with a prior fragility fracture or prior diagnosis of osteoporosis, prescription rates remained low. Moreover, in all three groups, new bisphosphonate prescriptions dipped between the 2007-09 and 2010-12 time periods. This may be partly due to recent negative media attention regarding the association of bisphosphonates with rare but serious side effects (i.e. osteonecrosis of the jaw and atypical femoral fracture).
Medical Research: What should clinicians and patients take away from your report?
MedicalResearch: Fractures are a significant side effect of androgen deprivation therapy for prostate cancer and can significantly decrease a patient’s quality of life and well-being. As such, it would be appropriate for clinicians to review Canadian clinical practice guidelines and other relevant literature regarding bisphosphonates (and other approved prescription bone medications) regarding their role in improving bone health in men on ADT for prostate cancer. Bisphosphonates and other approved bone medications can significantly reduce the risk of fracture, especially in men at higher risk of fracture, and in these men the risks are almost always outweighed by the benefits.
Medical Research: What recommendations do you have for future research as a result of this study?
MedicalResearch: This study demonstrated the low rates of bisphosphonate prescriptions among men undergoing androgen deprivation therapy for prostate cancer, yet it does not shed light on the reasons as to why prescription rates are lower than expected. As such, there is a need for further investigation to discern whether this is due to limited clinician awareness with regards to bone health management, patient hesitance to use bisphosphonates due to their side effects, pill burden (i.e. already perceived as taking too many medications) or some other reason entirely. Results from this research could help scientists understand how best to improve the situation, and by extension, bone health and quality of life, in men with prostate cancer.