Abstracts

Rationale: Non-syndromic focal epilepsy (NSFE) is a heterogeneous clinical disorder including patients with severe refractory forms and patients with a fairly good prognosis. Predictors of prognosis in NSFE are poorly understood. Methods: Two thousand, two hundred and twenty-six patients were evaluated for from April 1987 to September 2011 in two Epilepsy Centers located in Reggio Calabria and Catanzaro, Calabria, Southern Italy. One thousand and sixty-seven patients were excluded because of insufficient anamnestic data, psychogenic seizures, major psychiatric disorders, isolated seizures, idiopathic focal epilepsy of childhood, absence of neuroimaging study or presence of brain lesions except for scattered T2-hyperintense spots on hemispheric white matter, or, finally, for having received the diagnosis of NSFE elsewhere. The following variables were considered: age, gender, age at onset of epilepsy, family history of epilepsy or febrile seizures (FS), perinatal factors, personal history of FS, personal history of status epilepticus, type of seizures, presumed lobar localization (frontal, temporal, parietal, occipital, undetermined), interictal EEG (normal, abnormal, unilateral, abnormal bilateral). Survival curves were generated according to the Kaplan-Meier method and compared with the log-rank test. The end point was the cumulative time-dependent chance of 5- yrs remission after treatment start. Independent predictors of remission were tested by multivariate analysis using Cox proportional hazards function models. Results: The sample included 599 patients (289 women and 310 men) aged 4 to 100 years who were followed for 2336 person-years. Forty-six cases presented 5-yr remission during follow-up. The cumulative probability of remission was 20% at 5 years, and 25, 40, and 45% at 10, 20, and 30 years. At univariate analysis, factors predicting remission included family history of epilepsy or FS (p=0,03) and epilepsy originating from frontal lobe (p=0,04). Cox regression model confirmed frontal epilepsy as a positive predictor of remission. Conclusions: About 45% of cases with new-onset NSFE attain 5-yr seizure remission at some time during follow-up. Familiarity for epilepsy or FS and frontal lobe epilepsy are prognostic predictors.