Latency to treatment of status epilepticus is associated with mortality and functional status

Abstract

Introduction Status epilepticus (SE) is a life-threatening neurologic emergency. Despite advances in management, in-hospital mortality remains unchanged. This is partly due to the pharmacoresistance which develops the longer that seizures persist. Therefore, rapid antiseizure medication (ASM) administration may represent a beneficial treatment option. The purpose of this study was to determine: 1) whether in-hospital mortality is reduced with shorter latencies to initial treatment of SE with an ASM (LTSE); and 2) the critical time frame during which LTSE is associated with reduced in-hospital mortality. Materials and methods This was a retrospective, single-center study of adults diagnosed with SE between 1/1/2005 and 10/31/2012. Demographic characteristics included seizure history, etiology, semiology, and duration. Subjects were assigned to LTSE groups at the time frames of 5, 10, 30 and 60 min. The primary outcome was in-hospital mortality, with poor functional status (mRS 3–6) as a secondary measure. Pearson's chi-square, Mann-Whitney-U, two-sample-t-tests, and binary logistic regression analysis were used as appropriate, with p < 0.05. Results In unadjusted analysis, LTSE > 30 min demonstrated increased risk of mortality (OR 2.06, CI 1.01–4.17, p = 0.046) and poor functional status (OR 2.48, CI 1.05–5.85, p = 0.038) compared to LTSE ≤ 30 min. Increased mortality risk remained after adjusting for SE duration (OR 2.07, CI 1.01–4.26, p = 0.047) and nonconvulsive seizures (OR 2.28, CI 1.08–4.80, p = 0.03). Compared to subjects treated within 60 min, those treated after 60 min were at increased risk of poor functional status, regardless of the presence of nonconvulsive seizures (OR 2.96, CI 1.14–7.73, p = 0.026). In addition, when acute symptomatic SE was stratified by cardiac versus non-cardiac etiologies, subjects with non-cardiac acute symptomatic SE demonstrated worse functional outcome when treated after 60 min (OR 7.20, CI 1.13–46.07, p = 0.037). Conclusions Treatment of SE within 30 min of onset is associated with reduced risk of in-hospital mortality and poor functional status, although this may be attenuated by acute symptomatic seizures related to cardiac arrest. This represents a therapeutic option which has the potential to benefit patient outcomes.