Factors Associated with Refractoriness and Outcome in an Adult Status Epilepticus Cohort

Purpose: Several multinational prospective registers have shown that a significant proportion of status epilepticus (SE) patients are not treated in line with international guidelines. The aim of this study was to assess quality of treatment and to identify factors associated with refractoriness and outcome in a cohort of adult SE patients in Norway.

Methods: 151 patients treated in Oslo University Hospital from 2001 to 2017 were included. One SE-episode was selected per patient and variables related to the patient, SE-episode, treatment and outcome entered into a database. Status Epilepticus Severity Score (STESS) and Epidemiology-based Mortality Score in SE (EMSE) were calculated for each episode.

Results: 68% (n = 102) of SE-episodes were responsive, 20% (n = 30) refractory and 12% (n = 19) superrefractory. Mortality was 9%, with a significant difference between responsive episodes (1%) and refractory (superrefractory included) episodes (24%), p < 0.001. 86% of patients received a benzodiazepine as 1st antiepileptic drug. Multivariate analysis showed that non-convulsive SE in coma was significantly associated with refractoriness (p = 0.04), while focal non-convulsive SE without coma was associated with responsiveness (p = 0.03). Younger age was associated with superrefractoriness (p = 0.02). Regarding outcome, EMSE-EtiologyAgeComorbiditiesEEG (EACE)≥64 (p = 0.02) and use of vasopressors (p = 0.03) were associated with a worsening of the modified Rankin scale at discharge. STESS was only associated with outcome in univariate analysis.

Conclusion: In this cohort in which international guidelines for treatment of SE were well followed, semiology of the SE was found to be the most important determinant of refractoriness, and the new clinical scoring system EMSE-EACE was robustly associated with outcome.