Neuropsychological sequelae following pediatric stroke: a nonlinear model of age at lesion effects.

AIM: The distribution and quality of brain recovery following pediatric arterial ischemic stroke remains controversial. The literature suggests that age at stroke may be an important modulator of neuropsychological outcome, with reports inferring either greater vulnerability or plasticity in the nascent brain. Our aim was to investigate neuropsychological outcomes following pediatric stroke in a clinical sample with reference to age at lesion, lesion laterality, elapsed time from stroke to assessment, and persistent neurological sequelae.
METHODS: Using comprehensive neuropsychological assessment batteries, we investigated retrospectively a large (n = 44) and evenly distributed group of children who had ischemic stroke during "infancy" (1 month to 1 year), "early childhood" (1 to 6 years), and "late childhood" (6 to 16 years).
RESULTS: Children who suffered a stroke performed significantly worse on a range of neuropsychological measures when compared to a normative sample. However, children who suffered a stroke between 1 and 6 years old demonstrated better preserved neuropsychological profiles than either the earlier (before age 1) or later (after age 6) age groups. In addition, those children suffering a left hemisphere lesion performed more poorly on a range of neuropsychological measures than did children with right hemisphere lesions.
INTERPRETATION: Age at stroke is an important determinant of recovery following insult and may modulate neuropsychological and cognitive outcome.