Individual neuropsychological profiles at age 51/2 years in children born preterm in relation to medical risk factors

Follow-up studies of preterm children have reported a range of cognitive deficits, particularly in executive functions, visuospatial abilities, and learning. However, few researchers have adopted a person-oriented approach, exploring individual neuropsychological profiles. The aim of this study was to identify typical neuropsychological profiles among preterm children and control children, respectively. A second aim was to investigate if neuropsychological profiles at age 51/2 might be associated with perinatal medical risk factors. As part of the longitudinal Stockholm Neonatal Project, NEPSY for 4- to 7-year-old children (Korkman, 1990), WPPSI-R, and Movement ABC were administered at age 51/2 years to 145 preterm (mean gestational age 28 weeks) and 117 control children born at term. For the present study, the NEPSY results of each child were transformed into summary z scores for each of 5 neuropsychological domains: attention, memory, sensory-motor, verbal, and visuospatial functions. Subsequently, Ward's cluster analysis was performed for the preterm and control groups separately, identifying 5 neuropsychological profiles in both groups explaining around 56% and 57% of the variance, respectively. Overall, preterm children had lower neuropsychological results but also more diverging profiles compared to controls. The variability in outcome could not be sufficiently explained by birth weight, gestational age, or medical risks. The results suggest that prematurity interacts dynamically with genetic, medical, and environmental factors in neuropsychological development.