Bone health among prostate cancer survivors: Long-term follow-up from the Prostate Cancer Outcomes Study (PCOS).

Abstract

106 Background: Bone complications of androgen deprivation therapy (ADT) have been described using administrative databases and smaller prospective studies with relatively short follow-up. Prospectively acquired data with long term follow-up are lacking. We assessed the relationship of patient-reported bone health and ADT exposure in a population-based prospective cohort of prostate cancer survivors followed longitudinally for 15 years from diagnosis. Methods: Using PCOS 15 year patient-reported survey data, we identified men with non-metastatic prostate cancer diagnosed from 1994-1995 and followed through 2009-2010. We evaluated subgroups receiving >1 yr, ≤1 yr, and no ADT. We then queried participants regarding the development of osteoporosis, fracture, and use of osteoporosis medications. We assessed the relationship between duration of ADT and bone health outcomes using univariable logistic regression models, and evaluated the association between ADT and osteoporosis medications using multivariable logistic regression adjusted for PSA and geographic location. Results: Among 961 men who completed 15 year surveys, 157 received >1 yr ADT, 120 received ≤1 yr ADT, and 684 did not receive ADT. During the study period, 12 men developed bone metastases and were excluded from the fracture analysis (7 received >1 yr ADT, 2 received ≤1 yr ADT, and 3 did not receive ADT). Men receiving >1 yr ADT were more likely to report osteoporosis (OR 4.29, 95% CI 2.38-7.71) or fracture (OR 1.73, 95% CI 1.04-2.89) than men not receiving ADT. When compared with men not receiving ADT, men receiving >1 yr ADT were more likely to report bone mineral density testing (OR 4.59, 95% CI 3.09-6.83), and bone medication use (OR 3.22, 95% CI 2.19-4.72). Half (50.3%) of men treated for >1 yr ADT reported bone medication use. Among men who reported use of bone medications, 94% reported calcium or vitamin D use and 6% reported bisphosphonate use. Conclusions: Men treated with prolonged ADT (>1 yr) reported higher rates of osteoporosis and fracture at 15 year follow up. Accordingly, they reported more frequent screening and treatment for osteoporosis, with 50% of men receiving prolonged ADT reporting use of bone medications.