Large-scale study: PCa patients on hormone therapy at risk for heart disease

Hormone therapy used for the treatment of men with advanced prostate cancer is associated with an increased risk of developing various heart problems, according to findings from a study being called the largest and most comprehensive to examine this issue.

"If we have observed a causative effect, then for all hormone therapies put together, we estimate that compared with what’s normal in the general population, about 10 extra ischemic heart disease events a year will appear for every 1,000 prostate cancer patients treated with such drugs," said first author Mieke Van Hemelrijck, PhD, of King’s College, London.

"However, not all types of therapy were associated with the risk of heart problems to the same degree. We found that drugs which block testosterone from binding to the prostate cells were associated with the least heart risk, while those that reduce the production of testosterone were associated with a higher risk.

"This may have implications for treatment choice," said Dr. Van Hemelrijck, who presented the research at the joint 15th Congress of the European Cancer Organization and 34th Congress of the European Society for Medical Oncology in Berlin.

In the study, researchers analyzed the link in 30,642 Swedish men with locally advanced or metastatic prostate cancer who had received hormone therapy as primary treatment for their disease between 1997 and 2006. Most patients received one of the three hormone treatment choices, but 38% received a combination. They were followed for an average of 3 years.

Overall, prostate cancer patients treated with hormone therapy had a 24% increased risk of a non-fatal heart attack, a 19% increased risk of arrhythmia, a 31% increased risk of ischemic heart disease, and a 26% increased risk of heart failure. The risk of a fatal heart attack was increased by 28%, the risk of dying from heart disease by 21%, the risk of heart failure death was increased by 26%, and the risk of fatal arrhythmia was increased by 5%.

"We found that prostate cancer patients treated with hormone therapy had an elevated risk of developing all of the individual types of heart problems and that they were more likely than normal to die from those causes," Dr. Van Hemelrijck said, adding that the problems started happening within a few months of initiating treatment.

A more detailed analysis examining type of hormone therapy showed that the lowest increase in risk for ischemic heart disease, heart attack, and heart failure was seen in patients taking anti-androgen therapy, and no increase in risk of death from heart disease was seen in this group. Patients on gonadotropin-releasing hormone agonist therapy had the highest risk of these conditions, Dr. Van Hemelrijck said.