Abstracts

Rationale:
Status epilepticus (SE) is a common neurologic emergency with a high mortality. There has been extensive research on risk factors for in-hospital mortality after SE, however data on long-term outcomes is not well established. This is particularly true for non-convulsive status epilepticus (NCSE), with only limited literature available regarding the long-term significance of this condition. Given the dramatic increase in utilization of continuous EEG monitoring in critically ill patients and recognition of NCSE, it is crucial that we understand the long-term prognosis and how post-discharge outcomes compare with convulsive status epilepticus (CSE). We sought to determine the prevalence, severity, and post-discharge outcomes of SE, and to compare between those with CSE and NCSE.
Method:
Retrospective study of adult patients discharged from our hospital during 2017-2018, with a diagnosis of SE at admission or during hospital course. CSE was defined using standard criteria and NCSE defined by Salzberg criteria. Patients were divided into two groups for analysis: those with NCSE and those with CSE alone. Hospital records were used to determine the etiology of SE, number of anti-epileptic drugs (AEDs) required, the Status Epilepticus Severity Score (STESS) and demographic data. When available, post-discharge records were used to determine Glasgow Outcome Scale (GOS) and seizure recurrence. GOS scores of ≤ 3 were categorized as an unfavorable outcome. Results81 patients were included,17 had NCSE (21%). Patients with NCSE were more likely to be older in age and female gender compared with CSE alone (p = 0.017, 0.026). NCSE patients also required treatment with more AEDs, had longer hospital length of stay (LOS), and were more likely to have an unfavorable GOS than those with CSE alone (p = 0.0003, 0.006, 0.026). There was no difference in the etiology of SE, STESS, post-discharge seizure recurrence or number of AEDs at follow up between the two groups. Higher STESS was associated with in-hospital mortality (p = 0.023), however lower STESS was associated with post-discharge seizure recurrence (p = 0.0105). Post-discharge GOS was collected for 42 patients (33% with NCSE), with a mean follow up duration of 9.2 months.
Conclusion:
In our cohort of SE patients, those with NCSE required treatment with significantly more AEDs and had longer hospital LOS, suggesting that these patients had more refractory seizures and more complicated hospital courses. Patients with NCSE were also significantly more likely to have an unfavorable GOS at follow up post-discharge. Demographically, NCSE patients were more likely to be of older age and female gender compared to those with CSE alone.  As in previous studies, higher STESS at onset of SE was associated with in-hospital mortality. Interestingly, low STESS was associated with post-discharge seizure recurrence, providing further evidence with recent studies that suggests STESS may be of limited use in post-discharge prognosis.
Funding:
:No funding