Racial differences in bone mineral density and fractures in men receiving androgen deprivation therapy for prostate cancer.

212 Background: In the general population, black men have higher bone mineral density (BMD) and lower fracture rates than white men. Whether race influences bone loss and fracture risk during androgen deprivation therapy (ADT) for prostate cancer is unknown. Using data from a recently completed prospective, randomized, clinical trial we compared BMD and fracture rates of black and white men receiving ADT for prostate cancer. Methods: Subjects in these analyses (n=516) were members of the placebo group of a two-year randomized controlled trial of toremifene to prevent fractures in men receiving ADT for prostate cancer. All subjects resided in United States and reported their race as either black (n=68) or white (n=448). We compared baseline characteristics, including BMD and prevalent vertebral fractures, between black (n=68) and white men (n=448). We also compared changes in BMD and rates of new vertebral fractures over the two year study period. Results: Black men had higher baseline hip BMD than white men (0.98 ± 0.15 g/m2 and 0.91 ± 0.15 g/m2, respectively; p=0.001). Black men had similar BMD of the spine (1.09 ± 0.22 g/m2 and 1.11 ± 0.22 g/m2 in black and white men, respectively; p=0.51), but fewer prevalent vertebral fractures (7.4% versus 15.0%; p=0.13). Changes in BMD from baseline to 24 months were similar between black and white men (total hip percentage change −2.54 ± 0.26 in white men and −2.09 ± 0.60 in black men; p=0.55; lumbar spine percentage change −1.30 ± 0.33 in white men and −1.67 ± 0.71 in black men; p<0.71). Rates of new vertebral fractures trended towards being lower in black men (1.15% of black men versus 4.83% of white men; relative risk 0.24; p<0.12). Conclusions: Among men receiving ADT for prostate cancer, black men had higher baseline BMD at the hip and fewer prevalent vertebral fractures. Changes in BMD during ongoing ADT were similar for black and white men. Consistent with lower baseline risk for fracture, however, black men had fewer new vertebral fractures than white men. [Table: see text]