The endothelial activation and stress index as a risk factor for all-cause mortality in patients with anemia: a nationwide retrospective cross-sectional study.

Objectives: Limited evidence exists on the association between the endothelial activation and stress index (EASIX) and mortality in anemia patients. This national cross-sectional study investigated the relationship between the EASIX and all-cause mortality in anemic individuals and assessed its clinical utility.

Methods: We analyzed data from 2954 anemia patients in the NHANES (2003-2016), with mortality follow-up through December 31, 2019. Restricted cubic spline (RCS) analysis evaluated the EASIX-mortality association. The optimal EASIX cutoff value for survival was determined using the maximally selected rank statistics method (MSRSM). Weighted multivariate Cox regression and time-dependent receiver operating characteristic (ROC) curve analysis assessed EASIX's predictive performance.

Results: Over a median 81-month follow-up, 840 deaths (28.4%) occurred. RCS regression analysis revealed that higher EASIX scores were associated with increased all-cause mortality. Patients were categorized into lower (≤0.72) and higher (>0.72) EASIX groups based on the MSRM results. According to the multivariate-adjusted model, compared with the lower EASIX group, the higher EASIX group demonstrated an HR of 1.42 for all-cause mortality. Time-dependent ROC analysis revealed AUCs of 0.75, 0.75, 0.76, and 0.78 for 1-, 3-, 5-, and 10-year all-cause mortality, respectively.

Conclusions: An elevated EASIX score, derived from routine clinical parameters, is independently associated with increased all-cause mortality in anemic patients. These findings suggest that the EASIX may serve as a valuable prognostic biomarker for risk stratification and could assist in guiding the management of anemia. Further prospective cohort studies are needed to confirm its prognostic value in this population.