[Effectiveness and safety of long-term levetiracetam treatment in patients with refractory epilepsy].

Objective: To evaluate the long-term effects and tolerability of levetiracetam (LEV) in refractory epilepsy.

Methods: LEV was administered to 76 patients whose seizures were inadequately controlled by their current medications. The patients were followed for a minimum of 18 months but less than 2 years. The efficacy of LEV treatment was assessed retrospectively as the proportion of patients who experienced at least a 50% reduction in the frequency of seizures (50% RR), and adverse events were analyzed.

Results: The 50% RR in all 76 patients was 42%. The 50% RRs in the 54 patients with localization-related epilepsy and in the 20 patients with generalized epilepsy were 42% and 35%, respectively. The patients who responded most remarkably to the therapy, with at least a 75% reduction in the frequency of seizures, were more often those with localization-related epilepsy. Among adverse events, irritability and hyperactivity/impulsivity were observed more frequently in this study than in previous reports. These events were observed predominantly in patients suffering from autism or attention deficit hyperactivity disorder (AD/HD) as a comorbidity. γ-GTP values were improved in 14 of 17 patients whose values prior to beginning LEV treatment were higher than the normal range. This beneficial effect presumably resulted from a dose reduction or the discontinuation of other hepatotoxic antiepileptic drugs.

Conclusions: LEV was useful for the treatment of refractory epilepsy, and long-term efficacy was demonstrated. LEV also appeared to be less hepatotoxic. Behavioral changes should be monitored carefully when LEV is administered to patients with concomitant autism or AD/HD.