Is there a connection between dementia and prostate cancer medications that affect male hormones?
A new study by researchers from the University of Pennsylvania and Stanford University found that patients who had taken androgen deprivation therapy (ADT), which reduces levels of male hormones, had a higher risk of developing dementia than other prostate cancer patients.
Kevin Nead, a radiation oncology resident at Penn's Perelman School of Medicine, said the study, which was based on an analysis of records from two large hospital systems, did not provide enough evidence to change treatment decisions. Though the study found a correlation, it could not prove the therapy actually caused the dementia.
"Really, it tells us that we need to do more research," he said.
The study does, however, build on earlier work that found cognitive changes in men who took ADT.
ADT typically is given to men with intermediate-risk to advanced prostate cancer, Nead said. It has been shown to lengthen life.
The article, which was published in the Dec. 7 issue of the Journal of Clinical Oncology, estimates that half a million men in the United States are currently taking ADT.
The scientists examined records from 16,888 prostate cancer patients who had been treated at Stanford and Mt. Sinai Hospital in New York. They focused on 2,397 men who had received ADT and a control group of similar patients who had not. The median time to Alzheimer's diagnosis was 4 years.
Of the nearly 17,000 patients, 125 — 0.7 percent — were diagnosed with Alzheimer's disease.
Using a statistical method called propensity score-matched analysis, the team found that patients who had taken ADT were 88 percent more likely to be diagnosed with Alzheimer's. The risk rose the longer patients took ADT. Those who took it at least a year had more than twice the chance of getting an Alzheimer's diagnosis.