Executive function deficits are often reported as being a specific weakness in preterm born children. Yet, stability in function and development over time is largely unknown. In a prospective longitudinal study, 115 participants born very or extremely preterm, ≤ 31 weeks of gestation, participated in neuropsychological assessments at ages 5½ years and 18 years. Executive functions were separated into working memory and cognitive flexibility. Gestational age at birth, intrauterine growth, sex, perinatal medical complications, and parental education were tested as predictors, and developmental stability was investigated using Structural Equation Modeling. Working memory and cognitive flexibility were highly stable from preschool age to late adolescence. Higher parental education, higher gestational age, and female sex were related to better outcome at 5½ years which in turn fully mediated outcome at age 18 years. Perinatal medical complications and restricted intrauterine growth negatively influenced cognitive flexibility in late adolescence. The study poses an argument for identification of executive deficits before school entry among children born preterm, as such deficits are unlikely to diminish as a consequence of maturation.

Cognitive outcome after preterm birth is heterogeneous, and group level analyses may disguise individual variability in development. Using a person-oriented approach, this study investigated individual cognitive patterns and developmental trajectories from preschool age to late adolescence. As part of a prospective longitudinal study, 118 adolescents born preterm, with a birth weight <1,500 g, participated in neuropsychological assessments at age 5½ years and at 18 years. At each age, four cognitive indices, two tapping general ability and two tapping executive functions, were formed to reflect each individual’s cognitive profile. Cluster analyses were performed at each age separately, and individual movements between clusters across time were investigated. At both 5½ and 18 years, six distinct, and similar, cognitive patterns were identified. Executive functions were a weakness for some but not all subgroups, and verbal ability was a strength primarily among those whose overall performance fell within the normal range. Overall, cognitive ability at 5½ years was highly predictive of ability at age 18. Those who performed at low levels at 5½ did not catch-up, but rather deteriorated in relative performance. Over half of the individuals who performed above norm at 5½ years improved their relative performance by age 18. Among those performing around norm at 5½ years, half improved their relative performance over time, whereas the other half faced increased problems, indicating a need for further developmental monitoring. Perinatal factors were not conclusively related to outcome, stressing the need for cognitive follow-up assessment of the preterm born child before school entry.

Objective To investigate whether repeat courses of antenatal corticosteroids have long-term effects on cognitive and psychological functioning. Study design In a prospective cohort study, 58 adolescents and young adults (36 males) who had been exposed to 2-9 weekly courses of betamethasone in utero were assessed with neuropsychological tests and behavior self-reports. Unexposed subjects (n = 44, 25 males) matched for age, sex, and gestational age at birth served as a comparison group. In addition, individuals exposed in utero to a single course (n = 25, 14 males) were included for dose-response analysis. Group differences were investigated using multilevel linear modeling. Results Mean scores obtained in 2 measures of attention and speed were significantly lower in subjects exposed to 2 or more antenatal corticosteroids courses (Symbol Search, P = .009; Digit Span Forward, P = .02), but these were not dose-dependent. Exposure to repeat courses of antenatal corticosteroids was not associated with general deficits in higher cognitive functions, self-reported attention, adaptability, or overall psychological function. Conclusions Although this study indicates that repeat exposure to antenatal corticosteroids may have an impact on aspects of executive functioning, it does not provide support for the prevailing concern that such fetal exposure will have a major adverse impact on cognitive functions and psychological health later in life.