SEATTLE — Poor early control of seizures adversely affects neuropsychological development among school-aged children who are otherwise healthy, new data from a prospective, longitudinal study show.
“It's critical to delineate the timing and the course of neuropsychological deficits [in the childhood onset of epilepsy] and to identify the risk factors associated with them,” said Philip S. Fastenau, Ph.D., lead author of the study.
Dr. Fastenau and his coinvestigators enrolled children 6-14 years old who had a first recognized seizure, an IQ of at least 70, and no other chronic conditions affecting their activities of daily living. The children were matched with biological sibling controls who were of similar age, sex, and IQ, and had been raised in the same home.
Over the next 3 years, the investigators assessed seizure control every 9 months and performed neuropsychological testing at baseline (a mean of 2.4 months after seizure onset), at 18 months, and at 36 months.
The results were based on 209 children with new-onset seizures and 143 matched siblings. At baseline, half of those in the seizure group were receiving antiepileptic drugs, according to Dr. Fastenau, a neuropsychologist at the Case Medical Center, Cleveland. He reported having no relevant conflicts of interest with the study.
During the 3-year follow-up, 27% of the children with new-onset seizures did not have any recurrence, 61% had recurrent seizures (at least one more seizure, but not at every follow-up), and 12% had persistent seizures (seizures at every follow-up). In analyses that controlled for potential confounders, processing speed was similar across all three seizure groups and the sibling control group at baseline, Dr. Fastenau reported at the annual meeting of the American Epilepsy Society.
However, the 3-year change differed significantly. Processing speed increased for the siblings and the children who did not have a recurrence. In contrast, it decreased among children with recurrent seizures, and even more so among those with persistent seizures. Similarly, verbal memory and learning did not differ across groups at baseline, but the change during follow-up did.
Verbal memory and learning improved with time in the siblings and children with no recurrence of seizures, but worsened among the children with persistent seizures, a difference that was significant. It remained constant in the children with recurrent seizures.
At baseline, children with persistent seizures had significantly poorer attention, executive processing, and construction skills, compared with the siblings. During the 3-year follow-up, these skills increased in all four groups. However, the gain was significantly smaller in the persistent seizure group, compared with the sibling group.
“Seizure recurrence and persistent seizures, in particular, are associated with neuropsychological decline within the first 3 years after onset,” Dr. Fastenau said.
“In children with school-age onset [of seizures], complete seizure control is critical for optimizing cognitive development, but this goal might need to be balanced against the iatrogenic effects of some antiepileptic drugs,” he said.