Contemporary Population-Based Analysis of Bone Mineral Density Testing in Men Initiating Androgen Deprivation Therapy for Prostate Cancer.

ABSTRACT

BACKGROUND: Androgen deprivation therapy (ADT) is a cornerstone of treatment for advanced prostate cancer (PCa); however, it accelerates the loss of bone mineral density (BMD), which increases fracture risk. Guidelines recommend BMD testing when initiating ADT to assess baseline fracture risk properly. The objective of this study was to examine the proportion of BMD testing in men initiating ADT in Quebec and to identify factors associated with receipt of this testing. METHODS: The study cohort consisted of men extracted from Quebec public healthcare insurance administrative databases who initiated continuous ADT from 2000 to 2015 for >12 months. The primary study outcome was receipt of BMD testing in the period from 6 months before through 12 months after ADT initiation. Multivariable generalized linear mixed regression modeling with a logit link was performed to identify variables associated with BMD testing. RESULTS: We identified 22,033 patients, of whom 3,910 (17.8%) underwent BMD testing. Rates of BMD testing increased from 4.1% in 2000 to 23.4% in 2015. After multivariable analyses, prior history of osteoporosis (odds ratio [OR], 1.84; 95% CI, 1.32-2.57; P<.001), rheumatoid arthritis (OR, 1.64; 95% CI, 1.15-2.34; P=.006), use of bisphosphonates (OR, 1.47; 95% CI, 1.25-1.73; P<.001), and long-term corticosteroid use (OR, 1.63; 95% CI, 1.15-2.31; P=.006) were associated with higher odds of BMD testing. Patient age >80 years (OR, 0.67; 95% CI, 0.59-0.76; P<.001), metastases (OR, 0.79; 95% CI, 0.70-0.89; P<.001), higher Charlson comorbidity score (OR, 0.65; 95% CI, 0.51-0.81; P<.001), and rural residence (OR, 0.77; 95% CI, 0.68-0.87; P<.001) were associated with lower odds of BMD testing. CONCLUSIONS: In our study population, BMD testing rates in men initiating ADT were low, although they increased over the years especially in the years after the publication of recommendations for BMD testing in these patients. Potential gaps identified include being older, more comorbid, and rural areas. Overall, additional efforts emphasizing the importance of BMD testing in PCa guidelines may be needed.