Cognitive and behavioural findings in children with frontal lobe epilepsy

BackgroundFrontal Lobe Epilepsy (FLE) is the second most frequent type of partial epilepsy and its onset is generally in childhood. Though cognitive and behavioural impairments have been described as co-morbid disorders in epilepsy, their extent in FLE, particularly in children, remains unknown.AimsIn this study, we assess cognitive skills and behaviour in a cohort of paediatric FLE patients.MethodsWe measured the performance of 71 children with cryptogenic FLE on intelligence tests, neuropsychological tests, and behavioural questionnaires. Age-dependent normative values were used for reference. Results were related to epilepsy-factors including age at epilepsy onset, duration of epilepsy, seizure frequency, localisation of the epileptic focus and drug load.ResultsPaediatric FLE patients performed worse on intellectual and neuropsychological tests compared to reference values, and had a delay in school achievement. The performance of patients was typically worse on tasks measuring visual-spatial functions, memory, psychomotor speed and alertness. High seizure frequency was associated with lower scores on the arithmetic subtest of the intelligence scale; the other epilepsy-factors had no statistically significant influence on intelligence test or neuropsychological test outcome. Behavioural problems included attention problems, anxiety and internalising behaviour. These were not significantly related to epilepsy-factors.ConclusionsChildren with cryptogenic FLE show a broad range of cognitive and behavioural impairments, compared to reference values. While high seizure frequency may affect performance on selected cognitive measures, other epilepsy-factors do not seem to influence cognition and behaviour. Study of micro-structural or functional brain abnormalities that underlie these cognitive and behavioural impairments are warranted.