Relative influence of epileptic seizures and of epilepsy syndrome on cognitive function.
Cognitive impairment is frequently observed in children with epilepsy. We aimed at addressing to what extent cognitive function is affected by paroxysmal epileptiform activity with or without clinical seizures or by clinical features characteristic of the epilepsy syndrome. To this purpose, combined electroencephalographic (EEG) recording and cognitive testing (IQ and reaction times) were performed in 28 children. Frequent epileptiform EEG discharges significantly reduced reaction time, as did the occurrence of seizures during cognitive testing. Syndrome-related factors tended to affect cognitive functions as well: children with generalized epilepsy and high average seizure frequency obtained lower scores. Linear regression analysis showed that stable aspects of cognitive function, as reflected in intelligence level, are most closely related to the severity of the epilepsy syndrome (average seizure frequency), whereas transient aspects of cognitive function, such as reaction times, are related to the occurrence of epileptiform EEG discharges. This suggests that seizures have a direct effect on transient cognitive aspects, which can accumulate and result in effects on intelligence level.
Tromp
Selma C
SC
Department of Neurology, University Hospital of Maastricht, The Netherlands.
Weber
Jacobina W
JW
Aldenkamp
Albert P
AP
Arends
Johan
J
vander Linden
Inge
I
Diepman
Leonie
L
D000367:Age Factors; D002648:Child; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D004569:Electroencephalography; D004827:Epilepsy / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007361:Intelligence Tests; D008297:Male; D011446:Prospective Studies; D011930:Reaction Time / Q000502:physiology; D012307:Risk Factors; D012720:Severity of Illness Index; D013577:Syndrome