Epidemiology-Based Mortality Score is Associated with Long-Term Mortality after Status Epilepticus

Status epilepticus (SE) is a life-threatening condition with a high long-term mortality. The correct prediction of the individual patient's outcome is crucial for stratifying treatment. Status epilepticus severity score (STESS) and the epidemiology-based mortality score (EMSE) are well established for predicting in-hospital mortality; however, scores indicating long-term mortality are lacking. We here studied the association of both scores with mortality after discharge and long-term mortality.

In this retrospective cohort study of adult patients with incident, non-anoxic, first-time SE (from 01/2008 to 12/2014), STESS, EMSE-EACE (etiology-age-comorbidity-EEG), demographic data, modified Rankin Scale at discharge, treatment, date of diagnosis, and date of death were determined based on electronic patients charts.

A total of 129 patients with a median follow-up of 24.8 months were included. We found no significant difference between STESS and EMSE-EACE in predicting in-hospital and 3 months mortality. At end-of-study, EMSE-EACE with a cutoff of ≥ 64 showed the best association with overall survival. At last follow-up, only 15.7% (8 out of 51) of the patients with EMSE ≥ 64 were alive as compared to 32.4% (24 out of 74) of the patients with STESS ≥ 3. Median survival of patients with EMSE-EACE ≥ 64 and EMSE-EACE < 64 was 6.4 months (95% confidence interval (CI) 2.3-15.3 months) and 35.8 months (CI 32.8-37.9 months), respectively. In the subgroup of patients that were discharged alive from the hospital, EMSE-EACE was highly significantly associated with mortality (p < 0.001) after discharge. In the same patients, STESS with a cutoff of STESS ≥ 3 reached only borderline significance (p = 0.04), STESS with a cutoff of STESS ≥ 4 did not reach statistical significance (p = 0.23). Exploratory analyses of different EMSE components unveiled a strong association of etiology with in-house mortality but not with long-term survival. In patients discharged alive from the hospital, only comorbidity and age remained significantly associated with long-term mortality.

In our cohort, EMSE-EACE was significantly associated with long-term survival after discharge.