The endothelial activation and stress index as a key prognostic marker in severe ischemic stroke

Severe ischemic stroke (SIS) is a life-threatening condition associated with high mortality rates. Endothelial dysfunction plays a critical role in its progression, leading to further neurovascular damage. The endothelial activation and stress index (EASIX) is a simple and easily accessible biomarker and may serve as a potential prognostic indicator for SIS. This study investigates the relationship between EASIX levels and 28-day all-cause mortality (ACM) in patients with SIS.

The study utilized data from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. Patients were stratified into three cohorts based on log₂-transformed EASIX values. The association between EASIX and 28-day ACM in SIS was evaluated using Cox proportional hazards models, Kaplan-Meier survival analysis, restricted cubic spline (RCS) regression, and subgroup analyses. Receiver operating characteristic (ROC) curve analysis was performed to compare the predictive accuracy of EASIX with other prognostic markers.

A total of 786 patients with SIS were included in the study. The patients were stratified into tertiles based on their log₂(EASIX) values. Elevated EASIX levels were associated with prolonged hospital and ICU stays as well as an increased risk of 28-day ACM. Kaplan-Meier survival analysis revealed that higher EASIX levels significantly correlated with reduced survival probability. Cox regression analysis indicated that each unit increase in log₂(EASIX) was associated with a 17% higher mortality risk. Moreover, patients in the highest EASIX tertile exhibited a significantly greater mortality risk. RCS regression further identified a nonlinear increase in mortality risk beyond an EASIX threshold of 0.58. ROC analysis demonstrated that log₂(EASIX) had superior predictive accuracy for 28-day ACM (AUC = 0.765), outperforming both the SOFA and SIRS scores. Subgroup analyses confirmed the robustness of this association across various patient characteristics, with no significant interactions.

EASIX is a simple and accessible biomarker that provides early warning for identifying high-risk patients. Elevated EASIX levels are strongly associated with an increased risk of 28-day ACM in SIS patients.