Clinical predictors in patients with refractory epilepsy exposed to levetiracetam: a single-center study

This aim of the study was to ascertain the importance of clinical parameters on the response to treatment in refractory epilepsy patients on levetiracetam (LEV).

We retrospectively evaluated medical records of 132 patients aged 17-78 years with refractory epilepsy (defined as a failure of at least two antiepileptic drugs due to the lack of efficacy) exposed to LEV. We analyzed the response (seizure freedom or continuing LEV) using logistic regression.

Of 132 patients exposed to LEV, 103 cases continued the drug. Of the discontinuations (29/132), 75% were for lack of efficacy and 25% for tolerability problems. Twenty-three percent of the previously refractory patients achieved seizure freedom for at least 1 year with LEV in combination therapy. The dose of LEV in 80% of seizure-free patients was 1000 mg/day or less. The duration of epilepsy, age and sex were not associated with response to LEV. Seizure freedom was associated with epileptic syndrome or etiology. If no specific syndrome was recognized, there was a significantly greater chance for response compared with temporal lobe epilepsy (OR 20.76; 95% CI 2.12-203.61).

Our study was based on the careful clinical evaluation of the patients with extensive use of video EEG (50%) and MRI scans (95%). These clinical predictors were evasive in previous studies. This study showed that they are worth pursuing but significantly larger groups of patients need to be investigated to reach significant findings.