Hormonal (Testosterone Lowering) Therapy (ADT) Linked to Increased Dementia Risk for Prostate Cancer Patients.
It isn’t often that a research finding appears in 4-5 e mail or other publications but such is the case herein. Researchers at Stanford University School of Medicine published a study entitled “Association Between Androgen Deprivation Therapy and the Risk of Dementia” in the journal Journal of the American Medical Association Oncology. They reported that men treated with testosterone-lowering drugs for their prostate cancer are more than twice as likely to develop dementia as those not receiving such treatment, according to a study that reviewed the medical records of nearly 10,000 patients. But, the study only found an association between ADT and dementia risk, not cause and effect. The researchers advised however that men undergoing androgen therapy shouldn’t stop the treatment based on these findings because more studies are needed to verify this potential link.
Last year, the research team at Stanford discovered that testosterone-lowering treatment was linked to a higher risk of developing Alzheimer’s disease. Since Alzheimer’s is commonly confused with vascular dementia, the team decided to explore if the association held true when including all types of dementia.
They identified medical records of 9,272 men with prostate cancer who had been treated between 1994 and 2003, of which 1,829 received testosterone-lowering treatment. To make sure results became as robust as possible, they first removed all patients who had dementia at prostate cancer diagnosis. Then, they matched treated and untreated patients with the same disease stages, to make sure the comparisons were valid.
The team discovered that within five years, 7.9 percent of those receiving testosterone-targeting treatment had developed dementia. Among patients not receiving such treatment, the number was 3.5 percent.
The risk is real and, depending on the prior dementia history of the patient alternative treatment treatment may be considered, particularly in light of a recent prospective study from the U.K., which showed that prostate cancer patients had the same chances of survival within a 10-year time frame, whether they received aggressive treatment or active monitoring. Only 1% of men died during the 10 years, suggesting that monitoring may be as good as treatment, without causing side effects.
According to an article in the Oct. 13th MedlinePlus published by the U.S. National Library of Medicine, one possible explanation is that androgens like testosterone are believed to be very important for neuron [brain cell] health. In the brain, the ability of neurons to repair themselves and not die off, those are at least partially regulated by androgens. A very reasonable theory would be if you don’t have those androgens around to have that protective effect, you would be more susceptible to developing dementia.
Based on the findings, researchers argue it makes sense to identify those at risk for dementia before considering testosterone-lowering treatment. Researchers, however, underscored that the data are derived from medical records, and that prospective clinical trials ultimately are needed to remove any doubts that testosterone-lowering treatments may trigger cognitive decline.
A slightly more extensive article for health professionals was published in the October 21st issue of Cancernetwork, home of the journal Oncology.