Prognostic impact of immune-related adverse events on patients with and without cardiovascular disease: a retrospective review

Background: The emergence of immune checkpoint inhibitors (ICIs) has brought about a paradigm shift in cancer treatment as the use of these drugs has become more frequent and for a longer duration. As a result of T-cell-mediated inflammation at the programmed cell death-1, programmed death-ligand-1, and cytotoxic T-lymphocyte antigen-4 pathways, immune-related adverse events (irAEs) occur in various organs and can cause a rare but potentially induced cardiotoxicity. Although irAEs are associated with the efficacy of ICI therapy and better prognosis, there is limited information about the correlation between irAEs and cardiotoxicity and whether the benefits of irAEs apply to patients with underlying cardiovascular disease. This study aimed to investigate the association of irAEs and treatment efficacy in patients undergoing ICI therapy with and without a cardiovascular history. Methods: We performed a retrospective review of the medical records of 409 consecutive patients who received ICI therapy from September 2014 to October 2019. Results: Median patient age was 69 years (29.6% were female). The median follow-up period was 278 days. In total, 69 (16.9%) patients had a history of any cardiovascular disease and 14 (3.4%) patients experienced cardiovascular irAEs after ICI administration. The rate of cardiovascular irAEs was higher in patients with prior non-cardiovascular irAEs than without. The prognosis of patients with irAEs (+) was significantly better than that of the patients without irAEs (P < 0.001); additionally, this tendency did not depend on the presence or absence of a cardiovascular history. Furthermore, the Cox proportional hazards analysis revealed that irAEs were an independent predictor of mortality. Conclusions: Although cardiovascular irAEs may be related to prior non-cardiovascular irAEs under ICI therapy, the occurrence of irAEs had a better prognostic impact and this tendency was not affected by cardiovascular history.