OBJECTIVES: Androgen deprivation therapy (ADT) is a cornerstone of advanced prostate cancer (PCa) treatment. However, it is associated with loss of bone mineral density (BMD) which increases fracture risk. Guidelines recommend BMD testing when initiating ADT to properly assess baseline fracture risk. The objective was to examine the proportion of BMD testing in men initiating long-term ADT in Quebec.

METHODS: The cohort consists of men extracted from Quebec public healthcare insurance administrative databases who were diagnosed with PCa from 2001-2015 and treated by long-term ADT. The primary outcome was the receipt of baseline BMD testing (defined as a BMD test in the period from 6 months prior to and up to 12 months after ADT initiation). Multivariable generalized linear mixed regression modeling with a logit link was performed to identify variables associated with baseline BMD testing while accounting for physician clustering.

RESULTS: We identified 6,410 patients who initiated ADT during the study period, of which 887 (12.6%) underwent baseline BMD testing. Rates of baseline BMD testing varied by year of ADT initiation, from 7.7% in 2001-2003 to 13.3% in 2007-2009 and to 12.3% in 2013-2012. Following multivariable analyses, later years of ADT initiation (2004-2006, 2007-2009, 2010-2012, 2013-2015) during the study period remained associated with higher odds of baseline BMD testing compared to the earlier years (2001-2003) (ORs ranging from 1.43-1.88; p<0.001). Conversely, patient age > 80 (OR 0.73; 95% CI 0.57-0.94; p=0.001), greater Charlson comorbidity score (OR 0.51; 95%CI 0.34-0.75; p=0.001), and rural residence (OR 0.60; 95%CI 0.48-0.75; p<0.001) were associated with lower odds of baseline BMD testing.

CONCLUSIONS: Rates of baseline BMD testing in men initiating ADT are low, although it increased over the study period. Potential gaps were identified in older, more comorbid patients, and rural areas. Overall, additional efforts emphasizing the importance of BMD testing in PCa guidelines may be needed.