Purpose: Luteinizing hormone-releasing hormone (LHRH) agonists are believed to have higher cardiovascular risk relative to gonadotropin-releasing hormone (GnRH) antagonists. However, previous studies have not consistently demonstrated this. We used real-world clinical practice data to evaluate differences in major adverse cardiovascular events (MACE) risk between LHRH agonists compared to a GnRH antagonist following androgen deprivation therapy (ADT) initiation.
Materials and methods: We performed a retrospective analysis of data in the Decision Resources Group (now Clarivate) Real World Evidence repository, which represents >300 million US patients from 1991 to 2020 across all US regions. Patients with prostate cancer who received at least 1 injection of ADT were included. The risks of MACE and all-cause mortality as independent endpoints were evaluated, Kaplan-Meier curves were constructed, and associations between MACE and all available confounding risk factors were evaluated by Cox regression analysis using Statistical Package for the Social Sciences.
Results: A total of 45,059 men with prostate cancer treated with ADT were analyzed. Overall, the risks of MACE and all-cause mortality were slightly lower in the first year after ADT initiation compared to subsequent years. MACE risk was higher for the GnRH antagonist compared to LHRH agonists (HR=1.62; 95% CI 1.21-2.18, P = .001). The risk of all-cause mortality was also higher for the GnRH antagonist vs LHRH agonists (HR=1.87; 95% CI 1.39-2.51, P < .001).
Conclusions: The adjusted incidence of MACE was higher for men treated with the GnRH antagonist compared to the LHRH agonists. The demographic and risk factors with the greatest impact on MACE risk were higher age, baseline metastasis, oncology (vs urology) setting, personal MACE history, antagonist (vs agonist), tobacco history, White (vs Black) race, and lower BMI.
Keywords: GnRH antagonist; LHRH agonist; cardiovascular risk; major adverse cardiovascular events (MACE); prostate cancer.