Background: A 3 year course of androgen deprivation therapy (ADT) is an effective treatment for high risk localized prostate cancer, however is associated with adverse cardiometabolic risk. Cardiovascular disease is the leading cause of death in men with prostate cancer. We aimed to evaluate whether baseline cardiovascular risk factors could predict increased mortality in men undergoing long-term ADT.
Methods: We conducted a prospective cohort study of men with prostate cancer newly commencing ADT referred to a dedicated ADT Clinic at a tertiary referral hospital (Austin Health, Victoria) between March 2007 and May 2016. Men who had commenced ADT at least 4 years prior to May 2016 were included. Death was ascertained by hospital medical record review. Kaplan-Meier survival analyses, Mantel-Cox log rank test to assess predictors, and Wilcoxon signed rank test were used. Median [interquartile range] are presented.
Results: Of the 218 eligible men, 106 had data for analysis over 4 years (91 lost to follow up, 21 deceased). At baseline, 64% had hypertension, 60% hypercholesterolemia, 83% overweight/obesity, 22% diabetes mellitus, 25% ischaemic heart disease, and 25% had smoking history. None of these cardiovascular risk factors predicted mortality after 4 years. The only predictor of death was increasing age (p<0.0001).
83 had ceased ADT at the 4 year mark (median duration on ADT 3.0 years [2.8, 3.0], off ADT 16.7 months [13.3, 26.2]. Waist circumference significantly increased by 3cm(p=0.005). Blood pressure was lowered (p=0.011) as was total cholesterol, LDL and triglycerides (all p<0.001), HOMA2-IR (p=0.84) and HbA1c remained stable (0.077).
Conclusions: Older men with prostate cancer commencing ADT have a significant cardiovascular risk burden which can, despite increasing central adiposity, be mitigated with proactive management. Although baseline cardiovascular risk burden did not predict medium-term mortality, further study is required to analyse whether adequately controlling these risk factors impacts on mortality.