Abstracts

Rationale: Patients with partial epilepsy, mostly with temporal lobe epilepsy due mesial temporal sclerosis (MTS), present a higher incidence of mood disorders and psychosis, when compared both to general population and to other epileptic syndromes. Determination of electroclinical profiles that could help predict the occurrence of psychiatric disorders (PD) in these patients might have a positive impact on their treatment and prognosis. Our study aimed to identify electroclinical risk factors for the occurrence and type of psychosis in a group of patients with mesial temporal sclerosis (MTS). Methods: The study included patients with epilepsy and uni or bilateral MTS, and excluded patients with: other lesions besides MTS, double pathology, or extratemporal ictal onset. All patients underwent psychiatric evaluations (structured questionnaire) and were classified according to DSM IV and ICD 10. Clinical epilepsy variables were: onset age, duration, presence of TCGS, seizure frequency, polytherapy, previous status, complex febrile seizures and laterality (determined by MRI) and epileptogenic zone (determined by interictal and ictal EEG). Results: We evaluated 63 patients (34 [47.2%] male) with mean age of 39,1 years. Left MTS occurred in 35 (48.6%), right MTS in 32 (44.4%) and bilateral MTS in 05 (6.9%). Out of these 27 (37.5%) presented mood disorders, 23 (31.9%) psychosis. Thirty-four (47.2%) patients were on psychoactive medications. Previous or current PD were absent in 22 (30.55%). Patients with psychoses had longer duration of epilepsy (mean 32.21 ys) when compared to controls (26.26 ys) and patients with depression (24.76 ys) (p=0.046). EEG epileptiform activity on right temporal lobe (p=0.024) were significantly associated with an increase risk for psychosis. Other clinical variables did not differ among groups. Conclusions: This study confirms that patients with MTS have a high prevalence of mood disorders and psychosis and displayed differences in the electroclinical profile. Most patients with MTS and psychosis presented right-sided changes in both MRI and EEG (interictal and ictal findings). Although correlations between laterality and PD are controversial, the present study is relevant because other possible factors, related to the development of such disorders were taken into account. Longer duration of epilepsy was related to MTS with psychosis, a finding in accordance with at least two current theories explaining this comorbidity.