ORLANDO—Androgen deprivation therapy (ADT) for prostate cancer may be associated with increased risk of death from cardiac disease in men aged 65 and older, according to a study presented at the 2007 ASCO Prostate Cancer Symposium (abstract 298). "At 5 years, men 65 and older who were on ADT had a 3% risk of dying from cardiac causes, compared with a 0.9% risk in men who were not on ADT," reported Henry K. Tsai, MD, a resident physician in the Harvard Radiation Oncology Program.
Androgen deprivation therapy is known to elevate body mass index, increase lipids, and induce the onset of diabetes, all of which raise the risk of death from heart disease, Dr. Tsai said. He and his colleagues investigated whether the use and duration of ADT was associated with time to cardiac mortality and all-cause mortality in men treated for prostate cancer by radical prostatectomy, brachytherapy, cryotherapy, and external-beam radiotherapy with and without androgen deprivation.
They reviewed data on 3,636 men treated for localized prostate cancer from the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) database, a national registry of prostate cancer patients. Of this number, 735 received ADT for 1 to 32.9 months (median duration, 4.1 months), and 2,901 did not receive ADT.
After controlling for age and coronary artery disease risk factors, the duration of ADT (adjusted HR 1.1, P = .01) and age (adjusted HR 1.1, P = .04) were significantly associated with a shorter time to cardiac mortality, Dr. Tsai said. After controlling for pretreatment PSA levels, Gleason score, and tumor category, the duration of ADT was also associated with a shorter time to all-cause mortality. When stratified by age (< 65 years vs > 65 years), the increase in cardiac mortality associated with ADT use remained significant in older men (P = .004) but not in younger men.
"Our results need to be validated in prospective studies in order to prove cause and effect, but they do suggest that we should monitor men who receive ADT more closely for cardiac disease risk," Dr. Tsai concluded.
