Original articleClinical and electroencephalographic follow-up after a first unprovoked seizure
Introduction
Seizure and epilepsy are not synonymous: epilepsy refers to recurrent unprovoked seizures [1], [2]. The onset of epilepsy usually occurs in childhood, and that explains the concern about the risk for recurrence after the first seizure [3], [4], [5]. Several factors predictive of recurrence have been pointed out—age of onset, sex, perinatal and family history, characteristics of the seizure, whether the child was awake or asleep at the time of seizure, and electroencephalographic epileptiform patterns—but no consensus has been reached [6], [7], [8], [9], [10], [11], [12].
Few studies about the risk factors for epilepsy [8], [10], [13] or the incidence and prevalence of epilepsy in Brazil have been conducted so far: some studies revealed prevalence rates of 1/1000 in the general population and 8/1000 among children 5 to 14 years of age [14], [15]. Therefore the purpose of this study was to evaluate clinical and electroencephalographic factors associated with the recurrence of seizures in childhood.
Section snippets
Methods
We followed a cohort of 109 children and adolescents age 1 month to 16 years who were consecutively observed 24 to 72 hours after the seizure at the Epilepsy Outpatient Service, Hospital de Clínicas de Porto Alegre, Brazil, from July 1999 to June 2002. Patients were included in the study if they had a first unprovoked seizure or multiple seizures occurring within 24 hours, and if they were not taking antiepileptic drugs. Either one parent or the person responsible for the child signed an
Demographic characteristics
Patients' ages ranged from 1 month to 16 years (mean = 6 years; S.D. = 1 year and 6 months). Most patients were 6 to 12 years of age. Seventy patients (64.2%) were male, and 39 (35.8%) female. Ninety-two patients (84.4%) were Caucasian, and 17 (16.5%), non-Caucasian. The educational level of patients matched age distribution, and the predominant educational level for parents was 8 years (68 parents, 62.4%). Table 1 summarizes the demographic characteristics and relative risk for subsequent
Discussion
According to the literature on epilepsy in childhood, the incidence of seizures is highest among Caucasian males 1 to 38 months old [8], [10], [18], [19], [20]. Camfield et al. [21] conducted a population-based study of the incidence of epilepsy in childhood and adolescence in Nova Scotia and found a rate of 48/100,000 in the 1- to 5-year age group, and 43/100,000 in the 6- to 10-year age group, with the lowest rates being observed in infants and adolescents. Hauser [22], however, conducted an
Acknowledgements
The authors thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico–CNPQ (Brazilian Agency for Scientific and Technological Development) for the support provided to the development of this study.
References (40)
Update on epilepsy in pediatric patients
Mayo Clinic Proc
(1996)- et al.
Prognosis of seizures occurring in the first year
Pediatr Neurol
(2000) - et al.
Seizure recurrence after a first generalized tonic-clonic seizure, in children, adolescents and young adults
Seizure
(1997) - et al.
Predictors of multiple seizures in a cohort of children prospectively followed from the time of their first unprovoked seizure
Ann Neurol
(2000) - et al.
Epilepsy after a first unprovoked seizure in childhood
Neurology
(1985) - Dodson E, Pellock JM. Epileptic syndromes. In: Pediatric epilepsy: Diagnosis and therapy, 2nd ed. New York: Demos,...
- et al.
Epidemiologia e história natural das epilepsias
- et al.
The risk of seizure recurrence following a first unprovoked seizureA quantitative review
Neurology
(1991) - et al.
EEG abnormalities in children with a first unprovoked seizure
Epilepsia
(1994) - et al.
Prognostic factors for recurrence of a first seizure during childhood
Arq Neuropsiquiatr
(1997)