Background: Outcome prediction in Status epilepticus (SE) aids in clinical decision-making, yet existing scores have limitations due to SE heterogeneity. Serum albumin is emerging as a readily available prognostic biomarker in various clinical conditions. This study evaluates hypoalbuminemia in predicting short- and long-term mortality.

Methods: Observational cohort study including non-hypoxic SE adult patients admitted to the University Hospital of Geneva (Switzerland) between 2015 and 2023. Primary outcomes were in-hospital and 6-month mortality.

Results: Four hundred and ninety-six patients were included, 46 (9.3%) died in hospital; 6-month outcome was available for 364 patients, 86 (23.6%) were not alive at follow-up. Hypoalbuminemia was associated with older age and patients' comorbidities. Binomial regression showed an independent correlation between hypoalbuminemia and short- (p = 0.005, OR = 3.35, 95% CI = 1.43-7.86) and long-term mortality (p = 0.001, OR = 3.59,95% CI = 1.75-7.35). The Status Epilepticus Severity Score (STESS) had an overall AUC of 0.754 (95% CI = 0.656-0.836) for predicting in-hospital mortality and of 0.684 (95% CI = 0.613-0.755) for 6-month mortality. Through an exploratory analysis, we replaced age with hypoalbuminemia in the STESS, creating the Albumin-STESS (A-STESS) score (0-6). The global A-STESS AUC significantly improved for both in-hospital (0.837, 95% CI = 0.760-0.916, p = 0.002) and 6-month (0.739, 95% CI = 0.688-0.826; p = 0.033) mortality prediction. A-STESS-3 cutoff demonstrated a strong sensitivity-specificity balance for both in-hospital (sensitivity = 0.88, specificity = 0.68, accuracy = 0.70) and 6-month (sensitivity = 0.67, specificity = 0.73, accuracy = 0.72) mortality.

Conclusions: Hypoalbuminemia is an easily measurable biomarker reflecting the overall patient's condition and is independently related to short- and long-term SE mortality. Integrating hypoalbuminemia into the STESS (A-STESS) significantly enhances mortality prediction. Future studies are needed to externally validate the A-STESS and evaluate the benefits of albumin supplementation in SE patient prognosis.