Cognitive development in children with Dravet syndrome

Slowing of cognitive skills represents one of the diagnostic criteria of Dravet syndrome. This Italian multicentric study aims at clarifying the roles of epilepsy and/or underlying genetic alteration in determining the cognitive outcome. The study includes infants that were either in follow-up (retrospective study: 26 cases) and newly diagnosed (prospective study: in progress). Our multicentric study shows that slowing of cognitive achievements becomes evident during the second year of life in all cases, and that the epilepsy phenotype indeed has a prognostic value. In this study the early appearance of absences and myoclonic seizures is associated with the worst cognitive outcome; whereas convulsive prolonged seizures do not seem to represent, per se, a bad prognostic factor for mental outcome. In this study, statistical analysis failed to reveal differences in the cognitive outcome with regard to the presence and type of SCN1A mutation.