Defining early seizure outcomes in pediatric epilepsy: The good, the bad and the in-between

Purpose: To examine different approaches to classifying seizure outcomes. Methods: In a prospective cohort study of children (N=613) with newly diagnosed epilepsy, seizure outcomes at 2 years were classified as 'good' (≥1 year remission), 'bad' or 'intractable' (≥2 AED failures, ≥1 seizure/month over ≥18 months), and 'indeterminate' (neither 'good' nor 'bad'). Outcomes at 2 years were compared to outcomes in those followed 4 or more years. The associations of three commonly studied prognostic factors, etiology, age at onset, and syndromic grouping with the three-level outcome were assessed. Results: 595 (97.1%) children were followed ≥2 years. A 'good', indeterminate, and 'bad' outcome was present in 314 (52.8%), 235 (38.3%), and 46 (7.7%) children. Problems with treatment were recorded in 64.7% of the indeterminate group. In 390 children followed ≥4 years, early 'good' and 'bad' outcomes persisted in ∼80%. About half of those with indeterminate 2-year outcomes later achieved remission, 8% met criteria for intractability, and 37% remained indeterminate. Most of the associations with etiology, age, and syndrome were due to variation in the proportion that met criteria for intractability and not remission. Conclusions: Many children have indeterminate outcomes, often in association with treatment issues. Clearly 'good' and 'bad' early outcomes can be identified and persist ≥2 years later. In the absence of pharmaco-resistance, lack of early remission (indeterminate outcome) is usually not associated with a bad outcome, at least over the next few years.