Late Emergence of Cognitive Deficits After Unilateral Neonatal Stroke

Abstract

Background and Purpose-Neonatal arterial ischemic stroke (AIS) affects a surprisingly large number of children each year, yet little is known about the long-term neuropsychological implications. Methods-Using age-appropriate Wechsler scales of intellectual ability, this longitudinal study examined 26 children with a history of acutely diagnosed unilateral neonatal AIS as preschoolers (3 years 6 months to 5 years 11 months) and again as grade-school students (6 years 1 month to 12 years 5 months), and contrasted performance with the normative sample of the test. Results-As preschoolers, patients' performance did not differ from the normative sample for Full Scale IQ, Verbal IQ, or Performance IQ, and there were no significant differences associated with infarct laterality. As school-age children, performance was significantly lower than the normative sample for Full Scale IQ Working Memory and Processing Speed, but not for Verbal IQ or Performance IQ. Contrasts between Time 1 and Time 2 revealed a significant decline in Full Scale IQ, which reflected emerging deficits in nonverbal reasoning, working memory, and processing speed. Individual subject analyses revealed that 69% of the children showed significant declines in 1 or more IQ index measures. We found no significant differences in cognitive performance associated with lesion laterality, though males performed more poorly than females on several cognitive measures at Time 2. Conclusions-These findings suggest that children with unilateral neonatal stroke, particularly males, are at increased risk for emerging deficits in higher-level cognitive skills during the school years. Continued follow-up of these children is needed, even those with no apparent deficits as toddlers or preschoolers.

Incidence and Outcomes of Symptomatic Neonatal Arterial Ischemic Stroke

“…Early assessments are not necessarily good predictors of intellectual outcomes at school. 35 Longer-term follow-up is necessary to determine the effect of "growing into deficit" and thus the long-term impacts of NAIS on cognition.…”

Antithrombotic Therapy in Neonates and Children

“…409 Long-term follow-up is critical because later defi cits with brain maturation often emerge. 410 Radiographic features may predict outcomes. 411,412 Recurrent stroke is very rare after AIS in the neonatal period.…”

Life After Perinatal Stroke

“…13,14 Because speech and other higher cognitive functions emerge later in childhood, children with perinatal stroke are considered to grow into their deficits when specific developmental stages are reached. 15 Long-term neuropsychological studies are now defining the evolution and spectrum of these higher order deficits. Because the Neonatal Arterial Ischemic Stroke (NAIS) syndrome dominates the published perinatal stroke literature, a categorical discussion of NAIS outcomes is provided, followed by succinct summaries of the remaining disease states.…”

“…20,37,38 However, prospective longitudinal studies have also demonstrated specific disorders of cognitive function that become more apparent with time. 15 Studies comparing matched controls are more likely to demonstrate specific differences. 39 Most studies report a relative preservation of verbal versus performance abilities.…”

“…12 Age at testing is critical because 1 study found near-normal IQ at preschool ages that shifted to significant deficits in the same children at school age. 15 Marked inconsistency across small, averaged populations suggests the possibility that at-risk subpopulations may be harboring the…”