The risk of epilepsy following febrile convulsions.

A cohort of 666 children who had convulsions with fever were followed to determine the risks of subsequent epilepsy. High risks were found in children with preexisting cerebral palsy or mental retardation. Other major risk factors were atypical features of the febrile convulsions (such as focal seizures) and duration of febrile seizures for 10 minuts or more. The risk of developing epilepsy by age 20 was about 6 percent for all children who had experienced febrile convulsions. However, this risk figure consisted of a combination of 2.5 percent of children without prior neurologic disorder or atypical or prolonged seizures, and 17 percent of those with such complications.