Prognostic value of neutrophil-to-lymphocyte ratio and cardiac troponin I in patients with immune checkpoint inhibitors-related myocarditis
Authors: Zheng Y , Chen Z , Song W , Xu Y , Zhao Z , Sun Y , Wang Y , Zhao J , Zhang X , Xu Y , Tse G , Li G , Hong L , Liu T 
Published: October 2024

Abstract

Background
Over the past decade, immune checkpoint inhibitors (ICIs) have significantly transformed cancer treatment. However, ICIs inevitably may cause a spectrum of immune-related adverse events, among which cardiovascular toxicity, particularly myocarditis, while infrequent, has garnered increasing attention due to its high fatality rate.

Purpose
We executed a multicenter study aimed at characterizing ICI-related myocarditis and risk factors influencing its prognosis.

Methods
The study included patients with ICIs-associated myocarditis at four medical centers in China from January 28, 2019 to June 15, 2023. Logistic regression was performed to explore the risk factors for the development of severe myocarditis. Receiver operating characteristic curves were conducted to assess the diagnostic abilities of biomarkers to distinguish severe myocarditis, and the performance and calibration were evaluated using Hosmer-Lemeshow test. Cox regression analysis was employed to investigate the influential risk factors affecting the prognosis of ICI-related myocarditis. Kaplan-Meier survival curve analyses were conducted to assess the differences in survival times among different myocarditis groups.

Results
35 ICIs-associated myocarditis patients were identified. 21 patients (60%) were classified as severe myocarditis, and they presented higher cardiac troponin I (cTnI) levels (P=0.013), higher N-terminal pro-B-type natriuretic peptide levels (P=0.031), higher creatine kinase (CK) levels (P=0.018), higher CK-MB levels (P=0.026), and higher neutrophil to lymphocyte ratio (NLR) levels (P=0.016) compared to non-severe myocarditis patients. Multivariate logistic regression showed that cTnI (adjusted odds ratio: 1.021, 95% confidence interval (CI): 1.002-1.039, P=0.03) and NLR (adjusted odds ratio: 1.890, 95% CI: 1.026-3.483, P=0.041) were the independent risk factors of ICI-associated severe myocarditis. The receiver operating characteristic curve showed an area under curve of 0.765 (95% CI: 0.601 to 0.929, P=0.013) for cTnI, and 0.773 for NLR (95% CI: 0.597 to 0.948, P=0.016). Multivariate COX regression showed that NLR (adjusted hazard ratio: 1.189, 95% CI: 1.028-1.376, P=0.020) and pneumonitis (adjusted hazard ratio: 8.142, 95% CI: 1.191-55.651, P=0.032) were the independent prognostic risk factor associated ICI- related myocarditis. Further Kaplan-Meier survival curve analysis showed that the survival rate among patients without pneumonitis and with low level of NLR significantly outstripped that of patients with pneumonitis (P=0.015) and high level of NLR (P=0.024).

Conclusions
As independent risk factors for the development of ICI-associated severe myocarditis, cTnI and NLR demonstrated a promising predictive utility for the identification of ICI-associated severe myocarditis. NLR and the presence of pneumonitis were identified as independent risk factors that significantly impacted the prognosis of ICI-related myocarditis.