Abstracts

Children with severe drug resistant epilepsy (SDRE) are at risk of cognitive impairments. Attention may play a role in those impairments, as it has been found defective both in children with benign rolandic epilepsy and complex partial seizures. Our aim is to explore selective, sustained and divided attention in 2 groups of children with SDRE, treated either medically or surgically. Attention in children with SDRE is compared with attention in the general population and relationships between attention and epilepsy variables studied. The effect of surgical control of epilepsy on attention is explored.
28 children with SDRE were tested in three specific aspects of attention with standardised measures at baseline and at 7 months follow-up. Ethical approval was obtained. Test of Everyday Attention for Children(TeaCh) and Faces were used to explore the different aspects of attention. Fourteen of the subjects had a substantial seizure reduction by epilepsy surgery immediately after baseline assessment. Fourteen did not have surgery, acting as controls. The pooled attention of the 28 patients at baseline was tested against the normal population. The relationships between attention and seizure frequency, age at first seizure, number of antiepileptic drugs, past history of convulsive status epilepticus, right hemisphere EEG involvement and frontal lobe involvement were studied using correlations. Repeated measures ANOVA was used to compare performance on attention at baseline and at follow-up in both surgical and control groups.
Children with SDRE showed deficits in selective (TeaCh) [mean 6.1 (3.0) p=0[lt]0.001] and divided attention (TeaCh) [mean 5.5 (4.1) p[lt]0.001] in comparison to the normal population. IQ was significantly correlated with attention, but no other variables were related to attention measures. At follow-up children who had epilepsy surgery tended to improve in Faces 3 minutes F(1,25)=4.0, p=0.057 and improved in Faces 6 minutes F(1,24)=5.4, p=0.03 in comparison to controls. In these two measures the pooled 28 subjects did not show impairment when compared to the general population.
Children with SDRE have impaired selective and divided attention in comparison to the normal population. This is probably related to the cause of the epilepsy rather than to the effect of seizures alone. The attention impairments are partly dependent on IQ. It is difficult to separate the primary pathology and the effects of early onset epilepsy as causes of attentional difficulties, but seizure relief by surgery does not invariably resolve these problems. Nevertheless children improve in the attentional tasks they were good at before, suggesting that learning processes might be facilitated by epilepsy control in tasks where there is not previous impairment
[Supported by: First author was supported by a grant (Ex 2001 33419023) from the Ministry of Education, University General Directorate, Spanish Government]