ASCO GU has given us a number of interesting posters, some of which I have already written about in prior posts. Another of these posters (abstract 232) was about an analysis by Ruessel and colleagues describing cardiovascular events among men with prostate cancer using German claims data. The researchers, in a retrospective study, attempted to both evaluate the relationship between androgen deprivation therapy (ADT) and cardiovascular events and to determine if the cardiovascular risk was different for men who were treated with GnRH antagonists vs. agonists.
They used a German research database from the Health Risk Institute. They compared men treated with GnRH agonists or antagonists against men who did not receive ADT during the years of 2009-2013. Their endpoint, a composite endpoint, included having a myocardial infarction or ischemic stroke along with an addition cardiovascular event, including myocardial infarction, sequelae of cerebrovascular disease, ischemic stroke, intra-cerebral hemorrhage, pulmonary embolism, phlebitis/thrombophlebitis, transient cerebral ischemic attack, and occlusion/stenosis of cerebral arteries.
The analysis included 4,436 men who received GnRH agonists, 133 who received GnRH antagonists, and 37,367 who did not receive ADT during this time period.
The men treated with ADT had greater co-morbidity burden, were older, and had higher risk of baseline cardiovascular disease than men not treated with ADT. Of these, 6.27%, 3.76%, and 4.62% experienced a myocardial infarction or ischemic stroke in the GnRH agonist, GnRH antagonist, and no ADT groups, respectively. Additionally, 11.27%, 7.52%, and 8.38% experienced cardiovascular events in the GnRH agonist, GnRH antagonist, and no ADT groups, respectively.
The summary of the raw rates of cardiovascular events were higher among men treated with ADT than among untreated men and that men treated with GnRH agonists experienced more frequent cardiovascular events than men treated with GnRH antagonists. The authors conclude that treatment with GnRH antagonists is associated with a lower rate of cardiovascular events than treatment with GnRH agonists. Not surprising. this conclusion is no different from the data we see from the United States.