Early versus late remission in a cohort of patients with newly diagnosed epilepsy.

Purpose: To count patients with newly diagnosed epilepsy entering early and late remission and to identify prognostic predictors of late remission.

Methods: Children and adults with previously untreated epilepsy from two Italian tertiary centers (Monza, Bari) were the study population. All patients received monotherapy at treatment start; drug choice and schedule were left to the physician's judgment. A retrospective audit was performed and the following prognostic predictors were identified: age, gender, putative etiology, first electroencephalography (EEG) record, neurologic and psychiatric examination, disease duration at diagnosis, seizure type(s) and number prior to starting treatment, epilepsy syndrome, and first antiepileptic drug. Early remission was defined by 2-year seizure control immediately after treatment start. Late remission was defined by 2-year seizure control achieved at least 24 months after treatment start. Prognostic predictors were assessed by logistic regression analysis, adjusting for age, gender, and center.

Results: One hundred seventy-four women and 178 men (mean age 31.5 years) were included and followed for 2399.6 person-years. The cumulative time-dependent probability of 2-year remission was 56.3% at 2 years after treatment start, and 62.6, 69.4, and 79.5% at 3, 5, and 10 years. One hundred fifteen patients (23.0%) achieved early remission and 38 patients (10.8%) achieved late remission. The interaction between partial seizures and number of seizures prior to treatment was the only independent predictor of late remission.

Discussion: The course of epilepsy and the chance of remission are together a complex and dynamic process, possibly explained by the diversity of the mechanisms underlying drug response and the use of an increasing number of drugs.