Comprehensive analysis of risk factors for the severity of immune checkpoint inhibitor-associated myocarditis in cancer patients

Abstract

Abstract Purpose To explore the predictive significance of patients’ clinical features and examination results, including blood laboratory tests, echocardiogram, cardiovascular magnetic resonance (CMR), and electrocardiogram (ECG), for the severity of immune checkpoint inhibitors (ICIs)-associated myocarditis. Methods Data from a real-world cohort of 81 cancer patients who developed ICI-associated myocarditis after immunotherapy were retrospectively analyzed. Myocarditis of Common Terminology Criteria for Adverse Events (CTCAE) grades 3-5 and the development of the major adverse cardiovascular event (MACE) were set as endpoints. Logistic regression was used to evaluate each parameter’s value in predicting myocarditis of grades 3-5 and MACE. Results Eventually, CTCAE grades 3-5 and MACE developed in 43/81 (53.1%) and 28/81 (34.6) cases, respectively. The occurrence of CTCAE grades 3-5 (HR, 95%CI: 4.48, 2.02-9.91, p<0.001) and MACE (HR, 95%CI: 16.21, 6.93-37.94, p<0.001) were strongly related to patients’ overall survival from ICI-associated myocarditis to death. The likelihood of CTCAE grades 3-5 and MACE increased with the accumulation of organs affected by the ICI-associated adverse events and initial clinical symptoms. Concurrent systematic therapies during ICI treatment did not raise the risk of myocarditis severity, while prior chemotherapy did. Apart from the classical cardiac markers, such as myoglobin, brain natriuretic peptide, and troponin T, a higher neutrophil ratio was also related to poorer cardiac outcomes, whereas a higher lymphocyte and monocyte ratios were predictors of favorable cardiac outcomes. Besides, the CD4+ T cell ratio and CD4/CD8 ratio were negatively related to CTCAE grades 3-5. Several cardiovascular magnetic resonance parameters were associated with myocarditis severity. In contrast, the predictive value of echocardiography and electrocardiogram was weak. Conclusions This study comprehensively evaluated the prognostic value of different patients’ clinical factors and examination results and discovered several predictors of severe ICI-associated myocarditis, which will facilitate early detection of severe ICI-associated myocarditis in patients receiving immunotherapy.