Albumin-Corrected Anion Gap And Mortality In Septic Intensive Care Patients: An Analysis Using Medical Information...

Early prognostic assessment is crucial for sepsis patients in intensive care units (ICU). This study investigated the relationship between the albumin-corrected anion gap (ACAG) and clinical outcomes in ICU patients with sepsis. This retrospective cohort study analyzed 8,286 sepsis patients from the MIMIC-IV (version 2.2) database. Primary outcomes were 30-day in-hospital mortality and 30-day ICU mortality. The authors used Kaplan-Meier analysis, log-rank tests, multivariable Cox regression, and restricted cubic spline (RCS) regression to evaluate associations between ACAG and the outcome. Subgroup analyses assessed consistency across different factors. Higher ACAG levels were significantly associated with increased mortality risks. As a continuous variable, ACAG independently predicted higher in-hospital mortality in fully adjusted models (HR 1.01, 95% CI 1.01-1.02, p < 0.001). Quartile analysis revealed that Q4 patients (ACAG > 26.62) had 41% higher in-hospital mortality risk than Q1 in fully adjusted models (HR 1.41, 95% CI 1.24-1.49, p < 0.001). For ICU mortality, Q4 showed 54% higher risk than Q1 (HR 1.54, 95% CI 1.41-1.75, p < 0.001), although continuous ACAG was not significant in the fully adjusted model (p = 0.099), suggesting a threshold effect. RCS analysis identified a nonlinear association with an inflection point at ACAG = 23. Subgroup analyses confirmed consistent effects, with significant interactions for body mass index, acute kidney injury, continuous renal replacement therapy, and mechanical ventilation. Higher ACAG levels are significantly associated with increased 30-day mortality in ICU sepsis patients, showing a nonlinear pattern with an inflection point at 23. Monitoring ACAG may aid risk assessment in critically ill sepsis patients, particularly when values exceed this threshold. Further research is needed to elucidate mechanisms and validate clinical utility.