De novo status epilepticus is associated with adverse outcome: An 11-year retrospective study in Hong Kong

PURPOSE To identify predictors of poor clinical outcome in patients presenting to the intensive care units with status epilepticus (SE), in particular for patients presenting with de novo status epileptics. METHODS A retrospective review was performed on patients admitted to the intensive care units with status epilepticus in two hospitals in Hong Kong over an 11-year period from 2003 to 2013. RESULTS A total of 87 SE cases were analyzed. The mean age of patients was 49.3 years (SD 14.9 years). Eighteen subjects (20.7%) had breakthrough seizure, which was the most common etiology for the status epilepticus episodes. Seventy-eight subjects (89.7%) had convulsive status epilepticus (CSE) and 9 subjects (10.3%) had non-convulsive status epilepticus (NCSE) on presentation. The 30-day mortality rate of all subjects was 18.4%. Non-convulsive status epilepticus was more common in patients with de novo status epilepticus when compared to those with existing history of epilepsy (15.5% Vs. 0%, p=0.03). Patients with de novo status epilepticus were older (52 Vs 43, p=0.009). De novo status epilepticus was associated with longer status duration (median 2.5 days, IQR 5 days), longer ICU stay (median 7.5 days, IQR 9 days) and poorer outcome (OR 4.15, 95% CI 1.53-11.2). CONCLUSIONS For patients presenting to intensive care units with status epilepticus, those with de novo status epileptics were older and were more likely to develop non-convulsive status epilepticus. De novo status epilepticus was associated with poorer outcome. Continuous EEG monitoring would help identifying NCSE and potentially help improving clinical outcomes.