Androgen deprivation in prostate cancer and the long-term risk of fracture

To determine the rate of bone mass loss and the risk of fracture induced by androgen deprivation therapy in patients with prostate cancer.

Prospective study in 2 phases. In the first phase, demographic variables, FRAX^®, bone mineral density and clinical fractures were collected, before starting the therapy and up to 1 year after ending the therapy. In the second phase, we conducted a telephone interview a mean of 8.5 years after the start of the study to assess new fractures.

We included 150 patients with a mean age of 67 years and a mean therapy duration of 24 months. Before starting the treatment, 62 patients (41%) showed osteoporosis or low bone mass in the densitometry. After the first year of treatment, the bone mineral density decreased a mean of 3.7% and 2.1% in the lumbar spine and femoral neck, respectively. At the end of the second and third year, the loss rate was lower. During the first phase of the study, 4 patients (2.7%) experienced a fracture. In the telephone interviews with 80 patients (53%), only 1 had experienced a fracture.

In the patients with prostate cancer and androgen deprivation therapy, greater bone loss occurred during the first year. When the treatment did not exceed 2 years, the absolute risk of fracture was low, and clinical fractures were uncommon in the short and long term.