Prostate Cancer Therapy Raises Risk of Stroke?

The controversial connection between hormone therapy and increased risk

Emergency Room DoctorsLike the more commonly discussed breast cancer and ovarian cancer in women, prostate cancer in men is a hormone-related disease. One of the most common hormone treatments for prostate cancer is androgen-deprivation therapy (ADT), which helps lower levels of testosterone and androgens in the body.

Many studies have questioned the safety of ADT, pointing to issues like increased risk of bone fractures[1] and cardiovascular disease,[2] namely stroke.[3] Yet, the connection between ADT and stroke remains controversial.

In an effort to shed some light on the subject, researchers from Taiwan looked at the risk of stroke in patients who had been recently diagnosed with prostate cancer.[4]

Hormone Therapy and Stroke Risk

Researchers culled information from the Taiwan National Health Insurance Programme database, which was compiled by the Taiwan National Health Research Institute in 2000.

They selected patients who had newly onset prostate cancer and who had not been diagnosed with any type of stroke. That resulted in 365 patients, 64 of whom had taken ADT for more than a month.

After a five-year follow-up, researchers found that of the 365 patients with newly diagnosed prostate cancer, 19 percent (68 total) had suffered a stroke. Of these 68 people, 11 had taken ADT, while 57 had not.

Of those that did suffer a stroke, 50 percent had an ischemic stroke, which is caused by a clot in an artery leading to the brain.

Based on this, they determined, “There was not significantly increased risk of ischaemic or haemorrhagic stroke for patients with [prostate cancer] treated with ADT compared to patients with [prostate cancer] who did not receive ADT.”

Could Lifestyle Influence Outcome?

Given the discrepancy between this finding and other studies that show a causal relationship between prostate cancer and stroke, researchers offered several possible explanations.

One is that a traditional Chinese/Taiwanese diet consists of large amounts of legumes, namely soybeans, which are high in phytoestrogens. Estrogen helps to mediate blood levels of testosterone, which is good for prostate cancer.

The other is that they only looked at newly diagnosed patients. Perhaps patients who had been diagnosed earlier, and therefore had been on ADT longer, would have had a greater risk of stroke.

Lastly, researchers noted that it might be difficult to translate their findings to a Western culture for a couple of reasons. First, is that fewer people in Taiwan are put on ADT (only 18 percent), whereas 33 percent of prostate cancer survivors in the United States receive ADT.

Second, the typical American diet and lifestyle is quite different from the more traditional Chinese diet. We consume less soy (or at least very different forms of soy), more meat, and more sugar and fat than our Asian counterparts. These factors can influence not only prostate cancer itself, but also risk of stroke.

To Med or Not To Med

Based on this study, it would appear that androgen-deprivation therapy neither increases your risk for nor protects you from stroke. But I have to admit a personal bias toward this study.

My father was a five-year survivor of prostate cancer. After a recurrence, he was placed on hormone therapy and four months later died of a hemorrhagic stroke. We were told that there was, indeed, a connection between prostate cancer and risk of stroke, but only after he died.

Based on this, as well as the findings that a small number of people taking ADT did in fact suffer from a stroke, I say there is no reason not to err on the side of caution.

If you have prostate cancer, talk with your physician about ways to naturally thin your blood. This can include taking two to four fish oil capsules a day, trying 200–400 mg of white willow bark daily, or just chewing a good, old-fashioned baby aspirin every day.

After all, prevention is always the best medicine.


[1] Shahinian, VB, et al. Risk of fracture after androgen deprivation for prostate cancer. N Engl J Med. 2005;352:154-64.

[2] Levine, GN, et al. Androgen-deprivation therapy in prostate cancer and cardiovascular risk: a science advisory from the American Heart Association, American Cancer Society, and American Urological Association: endorsed by the American Society for Radiation Oncology. Circulation. 2010;121:833-40.

[3] Van Hemelrijck, M, et al. Absolute and relative risk of cardiovascular disease in men with prostate cancer: results from the Population-Based PCBaSe Sweden. J Clin Oncol. 2010;28:3,448-56.

[4] Chung, SD, et al. Hormone therapy for prostate cancer and the risk of stroke: a 5-year follow-up study. BJU Int. 2011 Aug 24. [Epub ahead of print.]

Tags: , ,

Share |