Many men worldwide are placed on androgen deprivation (AD) therapy, also known as hormonal therapy, as their sole form of treatment for prostate cancer. But AD therapy is not without its side effects, and for some men, particularly those with diabetes, this treatment may put them at higher risk of dying from cardiovascular disease.
Who gets AD therapy? It’s complicated, says Trinity Bivalacqua, M.D., Ph.D., The Prostate Cancer Team Scholar. “Some men with high-risk prostate cancer (a Gleason score of 8 to 10) are treated with the combination of radiation therapy and AD from the start. Others receive it when their PSA begins to rise after treatment with surgery or radiation.”
Although studies have reported improved survival for men with locally advanced cancer who receive AD in addition to radiation therapy, “AD is also frequently used outside of these proven settings,” says Bivalacqua, “and for these men, longterm data on the clinical benefi ts are lacking.”
Why not just put men on AD?
Because shutting off the male hormones, or androgens, takes a toll on a man over time. It can lead to osteoporosis, loss of libido and erectile dysfunction, memory difficulties, weight gain, and atherosclerosis. “Of particular note,” cautions Bivalacqua, “a number of randomized control trials have shown an increased risk of death from cardiovascular disease, and new-onset obesity and diabetes.” Loss of testosterone is highly prevalent in men with diabetes and metabolic syndrome, a condition closely linked to the development of diabetes.
Even though AD has been prescribed for years, “little is known about its effects on the heart problems associated with aging and diabetes. Having more insight into these effects will help us make treatment decisions for older men.” Bivalacqua will use mouse models of aging and diabetes to find out more. “We hypothesize that the loss of testosterone will have profound effects on cardiac function by impairing endothelial function in the heart,” he says. In early experiments, he has noted impairment in both cardiac muscle and the functioning of blood vessels, as a result of a lack of male hormones.
Men who undergo AD for prostate cancer are often older and have several health problems — particularly diabetes and coronary artery disease. “These experiments have tremendous potential,” says Bivalacqua, “because they may help us predict future cardiovascular risk in men undergoing AD for prostate cancer treatment.”