Prognosis of Status Epilepticus

Virtual Special Editions are collections of targeted papers curated by a Guest Editor. Here Dr. Dominik Madžar, Universtitätsklinikum Erlangen, Germany (author of the Editor’s Choice article in Volume 56) talks about the Prognosis of Status Epilepticus.”

There is little doubt that seizure activity should be terminated as rapidly as possible in status epilepticus (SE). However, this may come at the price of putting a patient at risk of iatrogenic harm. Especially in its later stages, SE therapy should therefore be evaluated for of its risk-benefit ratio. Doing so requires knowledge on how modifiable and unmodifiable variables contribute to outcome in SE. In this Virtual Special Edition of Seizure – European Journal of Epilepsy we present a collection of papers that explore the factors affecting prognosis in SE.

SE is a heterogeneous disorder, and although many aspects influence outcome, several studies demonstrated the etiology underlying an SE episode to be crucial:

Malek et al. [1] compared mortality between SE patients with and without prior seizures, using billing data on more >3,000 SE patients, showing that mortality was highest among patients with no history of epilepsy. Lui et al. [2] made similar observations on a small cohort of patients from Hong Kong and found lack of a history of seizures to independently predict worse outcome at discharge. Sokic et al. [3] characterized causes of death in SE in a cohort of 750 patients and demonstrated short-term mortality to be primarily determined by the underlying SE etiology.

The large impact of etiology on outcome is also reflected by the fact that all four scoring tools existing for prediction of SE prognosis contain SE etiology as a key component. These scores are increasingly used in studies on SE outcome and comparison of their performances has gained considerable scientific attention:

Giovannini et al. [4] compared at the Status Epilepticus Severity Score (STESS) with the Epidemiology based Mortality Score in SE (EMSE) and found a higher prognostic value for EMSE with regards to mortality and functional outcome, while both scores did not reliably predict refractoriness to therapy. Ciurans et al. [5] in their study focused on the subgroup of patients with refractory status epilepticus (RSE) and among those observed both EMSE and STESS to solidly predict mortality, but only EMSE prognosticated functional outcome. Even among those patients requiring the most aggressive therapy, i.e. continuous administration of anesthetic agents, a multivariable model revealed the STESS to be an independent predictor in recent research by Santamarina et al.[6]. By the way, this study also found outcome to substantially depend on seizure duration, underscoring the importance of adequate therapy on prognosis in SE. Finally, our group compared all four available SE scoring tools with regards to prediction of in-hospital mortality and found none of them to clearly outperform the others with all having certain strengths and limitations [7].

It remains to be determined whether these scores may help establish therapeutic approaches more tailored to individual SE episodes based on prognostic considerations.