Aaberg KM, Bakken IJ, Lossius MI, Lund Søraas C, Tallur KK, Stoltenberg C, Chin R, Surén P. Short-term Seizure Outcomes in Childhood Epilepsy. Pediatrics. 2018 Jun;141(6).
BACKGROUND AND OBJECTIVES:
Seizure freedom is the optimal response to antiepileptic treatment. In previous studies, it has been shown that between 61% and 71% of children with epilepsy achieve seizure freedom, whereas 7% to 20% have drug-resistant epilepsy. The definition of drug resistance has not been consistent across studies, and there is a lack of contemporary population-based data. We used data from a large nationwide child cohort to provide such information, implementing the current standard definition of drug resistance.
The study was based on the Norwegian Mother and Child Cohort Study. Potential epilepsy cases were identified through registry linkages and parental questionnaires. Medical record reviews and parental interviews were used to collect clinical information and to classify seizures, epilepsies, and etiologies.
The cohort included 112 745 eligible children aged 3 to 13 years (median age 7 years) at end of follow-up. Of these, 600 were epilepsy cases with at least 1 year of follow-up since epilepsy onset (median follow-up time: 5.8 years). There were 178 (30%) who had developed drug-resistant epilepsy, 353 (59%) who had been seizure free for ≥1 year, and 69 (12%) with intermediate seizure outcomes. Having an identified cause of epilepsy (genetic, structural, metabolic, or infectious) was associated with unsatisfactory seizure outcome (48% drug resistance) and influenced the relative risk associated with other prognostic factors. Sociodemographic characteristics were not associated with short-term seizure outcomes.
Drug resistance occurs in 3 out of 10 children with epilepsy, whereas 6 out of 10 become seizure free. Having an identified cause of epilepsy is associated with poor response to treatment.
The goal of antiepileptic treatment is seizure freedom, but some children have drug-resistant epilepsy. To date, reliable data on the outcomes of antiepileptic therapy—how many children achieve seizure freedom, and how many don't—have not been available. The goal of a recent study was to address this gap in our knowledge about the outcomes of antiepileptic therapy in children with seizures…
Overall, 59% of the children had been seizure-free for at least 1 year, but 30% had developed drug-resistant epilepsy. An adjusted analysis looked at the relative risk of developing drug-resistant epilepsy and concluded that gender, a family history of epilepsy, and a history of febrile seizure were not associated with the risk of developing drug-resistant epilepsy. Individually, these factors had previously been found to be associated with drug-resistant epilepsy.
However, having three or more seizure types was positively associated with developing drug-resistant epilepsy as was having an identified cause of epilepsy (genetic, structural, metabolic, or infectious). The authors concluded that in this population-based cohort study 59% of the children with epilepsy achieved at least 1 year of freedom from seizures, 30% had drug-resistant epilepsy, and 12% had an indeterminate course.