Altered Brain Function, Structure, and Developmental Trajectory in Children Born Late Preterm

BACKGROUND: Late preterm birth (34-36 weeks’ gestation) is a common occurrence with potential for altered brain development. METHODS: This observational cohort study compared children at age 6-13 years based on the presence or absence of the historical risk factor of late preterm birth. Children completed a battery of cognitive assessments and underwent magnetic resonance imaging of the brain. RESULTS: Late preterm children (n=52) demonstrated slower processing speed (p=0.035) and scored more poorly in visual-spatial perception (p=0.032) and memory (p=0.007) than full term children (n=74). Parents of late preterm children reported more behavioral difficulty (p=0.004). There were no group differences in cognitive ability or academic achievement. Imaging revealed similar intracranial volumes but less total tissue and more cerebrospinal fluid (p=0.004) for late preterm children compared to full term children. The tissue difference was driven by differences in the cerebrum (p=0.028) and distributed across cortical (p=0.051) and subcortical tissue (p=0.047). Late preterm children had a relatively smaller thalamus (p=0.012) than full term children. Only full term children demonstrated significant decreases in cortical tissue volume (p<0.001) and thickness (p<0.001) with age. CONCLUSION: Late preterm birth may affect cognition, behavior, and brain structure well beyond infancy.