Long-term mortality after status epilepticus: A 5-year analysis study

To describe 5-year mortality after status epilepticus (SE) and identify factors associated with long-term survival. We also validated the prognostic performance of the Age, Consciousness, Duration (ACD) score and evaluated long-term survival across etiological categories defined by the Lattanzi classification of acute symptomatic SE.

Retrospective cohort analysis of a prospectively maintained database of consecutive patients ≥16 years of age with confirmed SE admitted to a tertiary epilepsy center (2011-2022). We excluded unclear diagnoses, hypoxic-anoxic etiologies, and incomplete follow-up. We recorded clinical variables and prognostic scores modified Status Epilepticus Severity Score (mSTESS), Epidemiology-based Mortality Status Epilepticus (EMSE), and Age, Consciousness, Duration (ACD). Mortality was assessed at discharge and annually up to 5 years.

We included 786 patients (mean age 63.4 years, 43.5% female). Five-year mortality was 50.3%, with 44.0% of deaths occurring within the first 2 years. Neurological causes accounted for 60.8% of deaths, and direct seizure-related causes represented 74.6% of neurological deaths. Independent predictors of higher long-term mortality were older age, higher premorbid mRS, absence of prior seizure history, comorbidity burden, systemic complications, and impaired consciousness during SE; convulsive and focal motor SE were associated with lower mortality risk. mSTESS and EMSE were associated with long-term mortality. In patients with less damaging etiologies, ACD predicted 5-year mortality (hazard ratio [HR] 1.163, 95% confidence interval [CI] 1.063-1.273; area under the curve [AUC] 0.717); ACD ≥10 corresponded to >50% 2-year mortality. Five-year mortality was 61.3% (acute-primary Central Nervous System (CNS) and 58.3% (acute-secondary CNS).

SE carries substantial long-term mortality, particularly within the first 2 years. Neurological and seizure-related causes were the most frequent. The Lattanzi classification and the ACD score retained long-term prognostic value.