Epidemiology and clinical characteristics of frontal absence seizures compared with primary absence seizures
Year: 2025
Type: article
Study design: Observational Study
Abstract: • Absence seizures with secondary bilateral synchrony may constitute a form of generalisation of persistent foci, frequently originating in frontal regions. • Frontal absence epilepsy accounts for up to 14% of all cases of childhood absence epilepsy and is characterised by absence seizures with identical semiology, duration, and age of onset, although with fewer seizures per day and poorer response to treatment. • Frontal absence epilepsy should be suspected in patients with absence seizures who do not respond to monotherapy; sleep EEG should always be performed in these cases to identify features suggestive of secondary bilateral synchrony. • Epidemiology and clinical characteristics of frontal absence seizures compared with primary absence seizures Absence seizures due to secondary bilateral synchrony may be a manifestation of frontal seizures, indistinguishable from primary absence epilepsy (PAE), with a different prognosis and control. There are few epidemiological studies on frontal absences (FAE) in the group of absence epilepsy (AE) in children. To describe the epidemiology of FAE in childhood and compare the characteristics, clinical evolution, and pharmacological response with PAE. Retrospective study of cases with AE in children under 14 years of age from 2013 to 2022 in a tertiary hospital. Demographic variables, number, duration and type of associated seizures, frontal EEG focality with and without relation to generalized discharge, pharmacological response and neuroimaging were comparatively studied. 94 patients with a median age of 8.6 years (6-10.1 years; 49 M/45 H) with AE were included. 84% presented exclusively absence seizures. Hyperventilation induced seizures in 94.2%; photoparoxysms present in 5.3%. They showed EEG focus, 63/94 and in 45/94 it was frontal. In 14/94 (14.8%) the frontal focality preceded the critical spike-wave discharge. The bivariate analysis did not show significant differences in age, time until the consultation, psychomotor development/behavior alteration, association of other types of seizures and triggers. The number of absences/days was significantly lower in the EAFs (p = 0.004) and the need for combination therapy was greater in the bivariate (p = 0.005) and multivariate (p = 0.035) analysis. FAE represents a significant percentage of AE with seizures of identical morphology, age, and duration, although with fewer seizures/day and a worse response to treatment. Las crisis de ausencia con sincronía bilateral secundaria pueden ser una manifestación de crisis frontales, indistinguibles de la epilepsia ausencias primarias (EAP), con un pronóstico y control diferentes. Existen pocos estudios epidemiológicos sobre epilepsia-ausencias frontales (EAF) en el conjunto de la epilepsia de ausencias (EA) en el niño. Describir la epidemiología en la infancia de la EAF y comparar las características, evolución clínica y respuesta farmacológica con las EAP. Estudio retrospectivo de casos con EA en menores de 14 años de 2013 a 2022 en un hospital terciario. Se estudiaron comparativamente variables demográficas, número, duración y tipo de crisis asociadas, focalidad-EEG frontal con y sin relación a la descarga generalizada, respuesta farmacológica y neuroimagen. Se incluyeron 94 pacientes con una edad mediana de 8,6 años (6-10,1 años; 49 M/45 H) con EA. El 84% presentaba exclusivamente crisis de ausencias. La hiperventilación indujo crisis en el 94.2%; fotoparoxismos presentes en el 5.3%. Mostraron focalidad EEG, 63/94 y en 45/94 ésta era frontal. En 14/94 (14.8%) la focalidad frontal precedía a la descarga punta-onda crítica. El análisis bivariante no mostró diferencias significativas en edad, tiempo hasta la consulta, alteración del desarrollo psicomotor/comportamiento, asociación de otro tipo de crisis y desencadenantes. El número de ausencias/día fue significativamente menor en las EAFs (p = 0,004) y fue mayor la necesidad de biterapia al análisis bivariante (p = 0.005) y multivariante (p = 0.035). La EAF supone un porcentaje importante de la epilepsia de ausencias con crisis de idéntica morfología, edad y duración, aunque con menos crisis/día y peor respuesta al tratamiento.
Source: Neurología (English Edition)
Authors: J.M. Ramos-Fernández, A. Extraviz Moreno, N. del Arco Guzmán, R. Calvo Medina, L. Rodríguez Santos, P. Navas Sánchez
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,034
OpenAlex ID: W4416525163