Abstracts

Rationale: To determine the frequency, etiology and predictors of refractory status epilepticus (RSE) defined as seizures resistant to two antiepileptic drugs at appropriate doses. Methods: We collected all consecutive patients with SE arriving at our center between March 2011-and March 2014. Patients with incomplete clinical data, younger than 16 years old or with post-anoxic SE were not included. We evaluated demographic data, etiology, seizure type, level of consciousness, and defined the presence of potential fatal etiology. Prognosis was calculated using the STESS scale (Status Epilepticus Severity Score) Subsequently, non-refractory status epilepticus (non-RSE) and RSE were compared. Results: We included 136 patients. Mean age: 62.01 ± 17.62 [19-95]. 54.4% male. 39.7% had a previous diagnosis of epilepsy. We classified 52 patients as having RSE (38.2%): 57.7% convulsive, non-convulsive 42.3%. Etiology of RSE was as follows: acute symptomatic 57%, remote symptomatic 23.1%, progressive symptomatic 5.8%, and cryptogenic or idiopathic 13.5%. 38.5% had a "potentially" fatal etiology. We found that patients with a non-convulsive status epilepticus in coma (p = 0.016), age older than 70 y.o. (p = 0.07) and a STESS ≥ 3 most often developed a RSE. Refractory group also showed a higher mortality (30.8%, p = 0.34) After a logistic regression with baseline variables (only known at patient arrival), only STESS score was independently associated with RSE (OR = 2.648 [95% CI: 1.197-5.859], p = 0.016). However, once the cause of SE was known, "potentially" fatal etiology became the main predictor of progression to a RSE (OR = 3.125 [95% CI: 1403 -6.961] p = 0.005) Conclusions: An unfavorable STESS score and a potentially fatal etiology establish an early risk of progression to RSE.