Androgen deprivation therapy may not increase risk of Alzheimer’s disease after all

In the journals

A study of almost 31,000 men whose prostate cancer had not spread found that the use of androgen deprivation therapy (ADT) was not associated with a higher risk of Alzheimer's disease. This counters previous studies that suggested a possible link. The results were published in the January 2017 Journal of Clinical Oncology.

ADT is used in prostate cancer treatment to eliminate testosterone, since the hormone can fuel the disease. Testosterone levels also are traditionally lower in men with Alzheimer's compared with control groups, which suggests there may be a connection between lowering testosterone and an increased risk of Alzheimer's. Previous studies that have explored this connection found that a low testosterone level caused by ADT was associated with a higher probability of developing Alzheimer's. But these studies often covered a shorter time period — for instance, one year or less — and it is doubtful that men were on ADT long enough to cause Alzheimer's.

In the new study, researchers looked at ADT's effect over a four-year-period, but any diagnosis of Alzheimer's within the first year was not counted. Half of the men took ADT as their initial treatment, while the other half did not. During the follow up, they found there was not an increased risk of Alzheimer's among the ADT users compared with those who did not take the therapy. The researchers noted that more studies are needed, but men with prostate cancer can be less concerned about dementia risk if they need ADT.