Admission inflammatory and immuno-nutritional indices and in-hospital mortality in emergency department patients admitted to intensive care: a retrospective cohort study.

Background: This study investigated whether admission-based composite inflammatory indices and C-reactive protein-to-albumin ratio (CAR) were associated with in-hospital mortality in adult patients admitted from the emergency department to the intensive care unit. Methods: This retrospective cohort study included 709 adult patients admitted to the intensive care unit (ICU) via the emergency department. Inflammatory and immuno-nutritional indices at the time of admission, including C-reactive protein/albumin ratio (CAR) and three Multi-Inflammatory Index variants were evaluated. MII-1, MII-2, and MII-3 were calculated as neutrophil to lymphocyte ratio × CRP, platelet to lymphocyte ratio × CRP, and systemic immune-inflammation index × CRP, respectively. Associations with in-hospital mortality were assessed using unadjusted analyses, age- and sex-adjusted Cox regression models and descriptive receiver operating characteristic analyses. Results: Non-survivors exhibited significantly higher median MII values and CAR levels compared with survivors in unadjusted analyses ( Conclusion: MII variants and CAR were associated with mortality in admission-based analyses. However, their discriminatory performance was limited. Overall, these findings support the interpretation of admission-based inflammatory indices as adjunctive markers of inflammatory burden rather than standalone prognostic tools in emergency-to-ICU patients.