Prevalence of osteoporosis and osteopenia during androgen deprivation (ADT) for prostate cancer: Baseline data from a large randomized controlled trial

Abstract

5116 Background: Androgen deprivation therapy (ADT) is the standard treatment for men with advanced prostate cancer. ADT decreases bone mineral density (BMD) and increases fracture risk although there is limited information about the prevalence of osteopenia and osteoporosis during ADT. We evaluated the baseline data from a large fracture prevention study to better characterize the prevalence of ostepenia and osteoporosis in men receiving ADT for prostate cancer. Methods: In an ongoing phase 3 fracture prevention study, 1,392 men = 50 years old with histologically documented prostate cancer and receiving ADT were randomized to placebo or toremifene 80 mg, a selective estrogen receptor modulator. The phase 3 study included men at increased risk of fracture based on age = 70 years or low baseline BMD of the hip or spine as assessed by dual energy x-ray absorptiometry. Subjects with metabolic bone disease or receiving treatment for osteoporosis were excluded. In the current analyses, we report the baseline BMD and prevalence of osteopenia (T score -1.0 to -2.5 total hip, femoral neck or spine) and osteoporosis (T score = -2.5 total hip, femoral neck or spine) for the 1,139 subjects older than 70 years. The analyses were restricted to subjects =70 years because these subjects were included in the study regardless of baseline BMD. Results: Mean (± standard deviation) age was 76 ± 7 years. Mean duration on ADT was 39 ± 36 months. For men 70 years of age or older, mean T scores for the total hip, femoral neck, and spine are -1.01 ± 1.14, -1.50 ± 1.06 and 0.37 ± 1.88 respectively. A total of 73% of subjects 70 years of age or older were classified with osteopenia (55%) or osteoporosis (18%). Conclusions: In this large cross- sectional analysis, the vast majority of older men receiving ADT for prostate cancer have either osteopenia or osteoporosis. These observations provide further evidence that close attention to skeletal health is warranted during ADT for prostate cancer. No significant financial relationships to disclose.