Calcium and vitamin D supplementation during androgen deprivation therapy did not prevent loss of bone mineral density among men with prostate cancer, according to study results.

Bone mineral density (BMD) loss is an adverse effect of ADT for men with prostate cancer. Doctors routinely recommend 500 mg to 1,000 mg calcium and 200 IU to 500 IU vitamin D per day as a supplement, according to background information in the study.

“Calcium and/or vitamin D supplementation to prevent loss of bone mineral density in these men seems so logical that no one had questioned whether it works,” Mridul Datta, PhD, a postdoctoral fellow at Wake Forest Baptist Medical Center, said in a press release.

Datta and colleagues reviewed guidelines for calcium and vitamin D supplementation.

They also analyzed the results of 12 clinical trials that evaluated a combined 2,399 men with prostate cancer who were undergoing ADT. Those trials compared the effects of calcium supplements, vitamin D supplements and other drugs on BMD.

Only one of the 12 trials showed an increase in BMD in the lumbar spine (0.99% in 12 months). The largest decrease in BMD in the lumbar spine was –4.9% in 12 months.

The trial results indicated that calcium supplementation of about 500 mg to 1,000 mg and vitamin D supplementation of 200 IU to 500 IU did not prevent BMD loss.

“It wouldn’t be so bad if there were simply no obvious benefit,” researcher Gary G. Schwartz, PhD, MPH, associate professor in the departments of cancer biology, urology, and epidemiology and prevention at Wake Forest Baptist Medical Center, said in the release. “The problem is that there is evidence that calcium supplements increase the risk of cardiovascular disease and aggressive prostate cancer, the very disease that we are trying to treat.”

Further studies are needed to evaluate the safety and efficacy of calcium and vitamin D supplementation in this patient population, the researchers wrote.

“Clinical trials to determine the risk-benefit ratio of calcium and vitamin D supplementation in men undergoing ADT for prostate cancer are urgently needed,” they concluded.

Source: Endocrine Today.