Potential Link Between Prostate Cancer Treatment and Dementia

Androgen deprivation therapy may increase the risk of developing dementia.

Researchers have recently discovered a significant link between a common hormone treatment for prostate cancer and dementia.

Investigators from the Perleman School of Medicine found that androgen deprivation therapy doubles the risk of developing Alzheimer’s disease, according to a study published by JAMA Oncology. These findings may cause alarm for the half-million men in the Unites States who have received this treatment since the 1940s, when it became the first-line treatment for prostate cancer.

“This is not an academic question anymore; this is really a clinical question that needs to be answered,” said lead author Kevin T. Nead, MD, MPhil. “We have 2 papers here showing very similar outcomes and magnitude of risk, which I think supports the case for this to be studied prospectively.”

Androgens are male hormones that stimulate prostate growth, and suppression of these hormones is typically seen in prostate cancer treatment. Reducing androgen activity and low testosterone is linked to obesity, diabetes, high blood pressure, and heart disease.

These conditions are all also risk factors of dementia, the researchers said. Other studies have also shown that androgen deprivation therapy and low testosterone are associated with cognitive deficits.

In the current study, researchers used a new text-processing method to examine medical records from men with prostate cancer from 1994 to 2013. They found that 9277 men were diagnosed with prostate cancer during this time, and 1826 received androgen deprivation therapy.

Researchers discovered that patients who received androgen deprivation therapy had an increased risk of dementia. The risk of developing dementia among patients who received androgen deprivation therapy was 7.9%, compared with only a 3.5% risk among patients who did not receive this treatment, according to the study.

These results were considered statistically significant, since the risk is more than doubled. These findings also suggested a dose-response effect because patients who received androgen deprivation therapy (ADT) for 12 or more months had the greatest risk of developing dementia.

Researchers also found that age was not a factor, and the risk was doubled in all age groups.

These findings could potentially be explained by evidence that testosterone has a protective effect on brain cells. By lowering testosterone, brain cells may be more at risk of developing dementia and Alzheimer’s disease, according to the study.

“As the population of older, long-term cancer survivors continues to rise, the health issues that cancer therapies can leave in their wake will become increasingly important,” Dr Nead said. “Further studies are needed to investigate the association between this therapy and dementias, given the significant patient and health system impacts if there are higher rates among the large group of patients undergoing ADT today.”