New onset status epilepticus and its long-term outcome: A cohort study

Abstract

Purpose: New onset status epilepticus (NOSE), a subtype of status epilepticus, is a neurological emergency associated with significant morbidity and mortality. This study aimed to analyze the phenotypic spectrum and outcomes of patients presenting with NOSE.

Methods: This prospective and retrospective descriptive study included patients presenting with NOSE over a 10-year period. Data collected included patient demographics, phenotypic characteristics of SE and its etiology, Status Epilepticus Severity Score (STESS), SE classification Axis-II, and Modified Rankin Scale (mRS) scores at admission and discharge. Functional outcomes and seizure status were assessed at least 6 months post-discharge. Prognostic factors for mortality and the development of epilepsy were also analyzed.

Results: A total of 208 patients were included, with a mean age of 41.97 ± 21.66 years, and a male predominance (57.1 %). Focal to bilateral tonic-clonic seizures were observed in 47.5 % of patients. The etiology was acute symptomatic in 35.57 % and remote symptomatic in 24 %. The median hospital stay was 4 days (range: 2.25-10.75 days). The mortality rate was 26.5 %, and 23 % of patients developed epilepsy with a median follow-up of 9 months. Higher age (≥ 50 years), elevated STESS, ICU admission, use of anesthetic agents, refractory status epilepticus (RSE), and new-onset refractory status epilepticus (NORSE) were significant risk factors for mortality (p<0.05). The development of epilepsy was associated with a higher number of antiseizure medications (ASM) at discharge, ICU admission, use of anesthetic agents, RSE, and NORSE (p<0.05).

Conclusion: NOSE is a neurological emergency with a variable etiology and significant long-term consequences. Approximately one-fourth of patients presenting with NOSE died, and another quarter developed epilepsy during a median follow-up of 9 months. Identifying and addressing the predictors of mortality and epilepsy development following NOSE may improve long-term outcomes.

Keywords: Mortality; New Onset Status Epilepsy (NOSE); New onset refractory status epilepticus (NORSE); Outcome; Status epilepticus.