Decrease of bone mineral density in Japanese patients with non-metastatic prostate cancer treated with androgen deprivation therapy

The aim of this study was to conduct a cross-sectional survey of investigations related to the bone mineral density (BMD) of both non-metastatic prostate cancer (NMPC) patients who have not yet received androgen deprivation therapy (ADT) and patients receiving prolonged ADT in Japan. Japanese male patients with NMPC who received continuous ADT or who were planning to receive ADT were enrolled in this study. Lumbar spine and femoral neck BMD was measured using dual-energy X-ray absorptiometry (DEXA). To assess patient characteristics, we searched medical records and questionnaires to determine whether they had any factors that could possibly affect BMD. A total of 230 patients with a mean age of 76.6 ± 6.4 years were evaluated. Of these, 151 (65.7%) were receiving ADT, and 79 (34.4%) had not yet received ADT. The mean duration of ADT was 37.4 ± 30.7 months. DEXA showed that as the duration of ADT increased, lumbar spine and femoral neck BMD decreased gradually (p = 0.0005 and p = 0.0014, respectively). Stepwise regression analyses revealed that the duration of ADT was a significant variable of both lumbar spine and femoral neck BMD. Moreover, as the duration of ADT increased, the prevalence of osteoporosis increased statistically (p = 0.0002). This study showed that ADT negatively affected lumbar spine and femoral neck BMD. It also showed a progressive increase in the prevalence of osteoporosis in Japanese NMPC patients with ADT.