Abstract
Down syndrome (DS) is the most common genetic cause of intellectual disability in
the United States. The prevalence of seizure in individuals with DS is 1 to 13%, and
infantile spasm (IS) occurs in 6 to 32% of those with seizures. Since IS is relatively
common in children with DS, it is important to understand the impact IS has on the
neurodevelopmental outcomes to provide appropriate anticipatory guidance to help maximize
the potential of these children. Our study is the first to compare the neurodevelopmental
outcomes of children with DS and IS (DS + IS) to children with DS and no history of
seizures (DS − IS). Using the Bayley scales of infant and Toddler development III,
we assessed the neurodevelopment of 29 subjects (8 DS + IS and 21 DS − IS). Neurodevelopmental
outcome was poor in the DS + IS cohort, but the delay in treatment does not appear
to contribute to any differences in their developmental scores. However, when compared
with children with DS − IS, the DS + IS cohort scored approximately 20 points less
in all domains including cognitive, motor, and language (p < 0.05). Our results indicate that IS may impact the neurodevelopmental outcomes
of children with DS + IS; thus, it is important to provide ongoing developmental and
educational assessments and potentially additional therapies for children with DS + IS.
Keywords
Down syndrome - infantile spasms - neurodevelopmental outcomes