Association of the Endothelial Activation and Stress Index with 7‑ Day In‑Hospital Mortality in Sepsis‑Induced Coagulopathy: Evidenc e from a Multicenter Study

Background Sepsis‑induced coagulopathy (SIC) is a complication resulting from endothelial injury during sepsis. The endothelial activation and stress index (EASIX) quantifies vascular endothelial dysfunction, but its prognostic value in coagulopathy has not been fully established. We aimed to evaluate the association between EASIX and 7‑day in‑hospital mortality among SIC patients. Methods We identified SIC patients in the Medical Information Mart for Intensive Care IV (MIMIC‑IV) and the eICU Collaborative Research Database (eICU‑CRD). For statistical analysis, EASIX was log₂-transformed and patients were then stratified into tertiles based on those transformed values. We compared baseline characteristics across tertiles and databases. Kaplan–Meier survival curves and Cox proportional hazards models assessed the impact of log₂(EASIX) on mortality. Restricted cubic splines explored potential non‑linear associations, and predefined subgroup analyses examined effect modification. Results A total of 11092 SIC patients were included. In both cohorts, those in the highest EASIX tertile (T3) were more often male, carried a heavier comorbidity burden, and experienced significantly higher 7‑day in‑hospital mortality. Restricted cubic spline analysis revealed a non‑linear relationship between log₂(EASIX) and mortality risk; separately, subgroup analyses demonstrated that the association between higher EASIX and mortality remained consistent across most strata. Conclusions EASIX is a reliable short‑term prognostic marker in patients with SIC, and elevated EASIX levels are associated with a significantly increased risk of adverse outcomes.