J Korean Child Neurol Soc.  1999 Oct;7(1):79-88.

The Risk of Seizure Recurrence After a First Unprovoked Seizure in Childhood : A Prospective Study

• Yoo SH
• Song JY
• Kim SH

Abstract

PURPOSE: Epilepsy is generally defined as a chronic condition characterized by recurrent unprovoked seizure. It is still controversial whether the long-term antiepileptic drugs(AED) treatment will be necessary in children with first unprovoked seizure. Cognitive and behavioral side effects of AEDs are especially important in developing children. Therefore the rationale of AED treatment in the children with first unprovoked seizure depends upon the seizure recurrence rate and presence of risk factors related with seizure recurrence. We are going to evaluate the risk of seizure recurrence and risk factors after a first unprovoked seizure in children.
METHODS
One hundred fifty eight patients presented with a first unprovoked seizure from July, 1994 to June, 1999 were prospectively followed by regular epilepsy clinic visit or telephone interview for a mean of 27 months. We analyzed overall recurrence risk and risk factors of seizure recurrence(EEG finding, etiology of seizure, seizure type, history of prior febrile convulsions, neurodevelopmental status prior to first seizure, presence of a Todd's paresis, family history of seizures, a seizure occuring while asleep, and duration of seizure) by Cox's proportional hazards model and Kaplan-Meier survival analysis.
RESULTS
In 158 patients with first unprovoked seizure, 61 (39%) patients experienced subsequent seizure. The cumulative risk of seizure recurrence was 28.5, 37.6, and 42.3% at 6, 12, and 18 months. The median time to recurrence was 3 months, with 72% of recurrence occurring within 6 months, 92% within 1 year, and 100% within 2 years. On univariate analysis, risk factors for seizure recurrence included an etiology of seizure and abnormal EEG. In idiopathic cases, the risk factor was an EEG abnormality.
CONCLUSION
Many of the children with a first unprovoked seizure will not have recurrences. The recurrence risk of a first unprovoked seizure in children have statistically correlated with the etiology of seizure(cryptogenic and symptomatic) and abnormal EEG. Children with an idiopathic first seizure and a normal EEG have a particularly favorable prognosis.

MeSH Terms

Ambulatory Care
Child
Electroencephalography
Epilepsy
Humans
Interviews as Topic
Paresis
Prognosis
Proportional Hazards Models
Prospective Studies*
Recurrence*
Risk Factors
Seizures*
Seizures, Febrile