Background: Cardiovascular toxicity of androgen deprivation therapy (ADT) for prostate cancer has been extensively discussed in recent years. However, systematic review of literature on ADT use in Asians revealed substantial heterogeneity in the limited data due to differences in study cohorts and research methods.
Objectives: To investigate the association between cardiovascular disease risks and androgen deprivation therapy in patients with prostate cancer in Hong Kong, which are representative of southern Chinese.
Methods: This was a retrospective cohort study with maximum 10-year follow-up. Data were retrieved from a population-based healthcare record database in Hong Kong. All patients with newly diagnosed prostate cancer between 2004 and 2020 were included. Patients who had received either surgical castration or pharmacological hormonal therapy, including gonadotropin releasing hormone analogs, anti-androgens, estrogen, and progesterone were considered exposed to androgen deprivation therapy. Primary outcome was a composite endpoint of major cardiovascular adverse events inclusive of acute myocardial infarction, ischemic stroke, and cardiac death. Propensity score matched cohort was analyzed using Cox proportional hazard regression and Kaplan-Meier estimator. We also used the Fine-Gray method to account for competing risks.
Results: We identified 19,923 patients (mean age 73 ± standard deviation 8.65) with incident prostate cancer between 2004 and 2020. After propensity score matching, 15,742 (7871 exposed and 7871 control) patients were included in the analysis, among which 1,478 patients experienced major cardiovascular adverse events during follow-up period. After adjusting for confounding, significantly elevated risk of major cardiovascular adverse events (hazard ratio 1.47, 95% confidence interval 1.32 - 1.63) associated with androgen deprivation therapy use was observed. Competing risk analysis using the Fine-Gray approach also corroborated with the result (hazard ratio 1.16, 95% confidence interval 1.05 - 1.28).
Conclusions: We demonstrated that the use of androgen deprivation therapy is associated with significantly increased risk of major cardiovascular adverse events among patients with prostate cancer in Hong Kong. Our findings emphasize the need for cardiovascular evaluation in all patients receiving androgen deprivation therapy.
