Abstracts

Rationale: We tried to evaluate the long-term efficacy and safety of Levetiracetam for the large population of patients in a tertiary epilepsy center. Methods: All the patients who had been treated with Levetiracetam at Seoul National University Hospital from 2007 to March 2009 were recruited. Medical records were retrospectively reviewed. Excluded were the patients who had prophylactic medication for brain surgery or unstable neurological conditions. Efficacy was measured using a five-point scale. Adverse events were also recorded. Retention rates in the 1st year, the 2nd year, and the 3rd year were calculated using a life-table method. Results: A total of 819 patients were recruited including 128 generalized epilepsy patients. Mean duration of follow up was 28.7 months. Seizure free rate was 36.6%, which was higher in generalized epilepsy (54.7%) than in localization related epilepsy (33.3%). For 188 patients with initial or second monotherapy, the seizure free rate was 61.7%. The number of prior antiepileptic drug was inversely correlated with seizure-free outcome. Dose-up response was strongly dependent on initial response. Tolerance was observed only in 83 patients (10.1%). The retention rates in the 1st year, the 2st year and the 3rd year were 76%, 72% and 69%, respectively. Among 819 patients, 211 patients were dropped out and main reasons of discontinuation were lack of efficacy (64.9%) and side effect (29.3%). A total of 309 adverse events developed in 235 patients. The crucial adverse events, that was correlated with drug discontinuation, were irritability (34%, p-value 0.044), somnolence (47.4%, p-value 0.002), psychosis (66.7%, p-value <0.001) and skin rash (100%, p-value 0.003).Conclusions: Levetiracetam was effective and safe for monotherapy and as an add-on therapy for partial and generalized epilepsies. The irritability, somnolence and psychosis were important adverse events of levetiracetam.