Abstracts

Rationale: The prevalence of epilepsy is high in people with mental retardation and they present multiple seizure types, often difficult to control. In addition, concomitant psychiatric disorders, behavioural factors and high susceptibility to side effects in this group of patients make therapeutic options for epilepsy particularly difficult. Levetiracetam (LEV)improves seizure control in this group of patients but behavioural side effects, mainly irritability and aggression, have been reported. Besides, LEV has been reported to be responsible of increased level of alertness, improving management and quality of life of people with mental disabilities. Methods: We reviewed clinical charts of all adult patients with epilepsy and mental retardation treated with LEV in monotherapy or in polytherapy referred to our Epilepsy Centre since 2000. Demographic characteristics of patients as well as clinical epilepsy and disability history were reported on a dedicated database. Patients started LEV at a daily dose of 250 mg, with progressive increments of 250 mg every week, according to clinical response. Between visits, parents and/or caregivers were advised to keep record of seizure severity and frequency on our standard charts. Side effects were reported at every visit. Results: 49 patients (26 men, 23 women) aged 19 to 57 years (media) were started on LEV treatment (range 500 mg/day-4000 mg/day, mean dose 1994,90 mg/day).Mean follow-up was 24 months (range 3 months-7 years). The patients had different severe epileptic syndromes: 37 patients (75%) suffered from focal epilepsies, 12 (25%) from generalized epilepsies. After LEV introduction, 2 patients (4%) became seizure free, 5 patients (10%) experienced a seizure reduction > 75%, 19 patients (39%) experienced a seizure reduction > 50%. 23 patients (47%) discontinued LEV: 4 (8%) because of side effects (aggressiveness and irritabilty), 18 (37%) because of inefficacy. Only one patient presented an increase of seizure frequency. Side effects more frequently reported were irritability (5 patients), aggressiveness (2 patients) and sedation (5 patients). Caregivers noted increase level of alertness and partecipation in 13 patients (26%). Conclusions: In our group of 49 patients with epilepsy and mental retardation, 49 % experienced a > 50% seizure reduction and 4% became seizure free. Only one patient experienced an increase in seizures with LEV. Adverse reactions were mainly mild and transient and only 8% of patients withdrew treatment because of side effects. Initial sedation and behavioural symptoms were more frequently reported, usually irritability and aggressiveness. Because these effects are dose-related, we recommend a slow titration of LEV (weekly increments of 250 mg) in order to achieve the minimal effective dose for each patient and to minimize the onset of behavioural reactions. We would stress the evidence of the role of LEV in increase alertness and thus improve quality of life also in this group of patients.