Cognitive-behavioral profiles in teenagers with Dravet syndrome

To investigate behavior and cognitive performances of teenage patients with Dravet syndrome (DS).

We enrolled 20 teenage patients (12 females and 8 males) with DS, followed in the Child Neurology Unit of the Catholic University (Rome). Patients underwent a full clinical examination including behavioral and cognitive assessments (respectively, CBCL and Wechsler scales).

All patients showed behavior disorders and mental retardation, mild in six cases, moderate in seven and severe in the remaining seven. Among mildly retarded patients visual function, particularly visuo-motor abilities resulted mostly impaired in Wechsler subtests, whereas verbal skills were relatively preserved. In contrast, a general cognitive impairment was observed in moderately and severely retarded patients.

Our teenage patients with DS compared with other series at different ages (young childhood, adulthood) suggest a progressivity of neurological and neuropsychological signs. A visuomotor default and a relative preservation of verbal skills, like what has been found in previous reports of younger patients, are still evident in mildly impaired cases. Therefore, the progression over time of these cases toward a generalized impairment may be suggested, but only longitudinal studies can confirm it. There was a possible responsibility of some epileptic disorders in worsening the neuropsychological outcome (early myoclonic seizures and atypical absences, as well as persistent EEG background slowness in the last 3years).