Neurodevelopmental comorbidities and seizure control 24 months after a first unprovoked seizure in children

Purpose: To follow children with newly diagnosed unprovoked seizures to determine (1) whether the prevalence of neurodevelopmental comorbidities and cerebral palsy (CP) changed after the initial seizure, and (2) the association between studied comorbidities and seizures 13-24 months after seizure onset or initiation of treatment. Methods: Analyses were based on 750 children (28 days-18 years) with a first unprovoked seizure (index) included in a population-based Incidence Registry in Stockholm between 2001 and 2006. The children were followed for two years and their medical records were examined for a priori defined neurodevelopmental/psychiatric comorbidities and CP and seizure frequency. Baseline information was collected from medical records from before, and up to six months after, the index seizure. Odds ratios (OR) of repeated seizures 13-24 months after the first seizure or after initiation of anti-epileptic drug treatment was calculated by logistic regression and adjusted for age and sex. Results: At baseline, 32% of the children had neurodevelopmental/psychiatric comorbidities or CP compared to 35%, 24 months later. Children with such comorbidities more often experienced seizures 13-24 months after the index seizure (OR 2.87, CI 2.07-3.99) with the highest OR in those with CP or attention deficit hyperactivity disorder (ADHD). Children diagnosed at age < 1 year exhibited the highest prevalence of comorbidities as well as OR for repeated seizures. A combination of young age and comorbidity was associated with an OR for repeated seizures of 5.12 (CI 3.03-8.65). Among the children without comorbidities 76% were seizure free 13-24 months after the index seizure or after initiation of AED treatment compared to 53% of children with comorbidities. Conclusions: This study indicates that neurodevelopmental comorbidities and CP in children with epilepsy tend to be present already at seizure onset and that such comorbidities are strong indicators of poor outcome regarding seizure control with or without treatment.