A longitudinal perspective on neurodevelomental outcome following infant cardiac transplantation

Abstract

Few studies have examined the neurodevelopmental sequelae associated with infant heart transplantation. Existing publications have generally reported one-time assessments of developmental status using varying outcome measures. The present study investigated longitudinal patterns of neurodevelopmental outcome in 41 children who were cardiac transplant recipients at Loma Linda University Childrens Hospital. The Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) of the Bayley Scales of Infant Development were used to monitor the performance of each child across four testing sessions (T). A Repeated Measures ANOVA (N=10) was conducted to test overall differences in MDI and PDI scores across the testing sessions. Although no statistically significant changes in PDI scores were apparent (F=2.685, p=.07, df=3), a trend of increased scores with repeated measurements was observed; however, a statistically significant change in MDI scores was noted (F =3.961, p=.020, df=3). Paired samples t-tests on the larger sample (N=41) showed a significant decline in average MDI scores between the first and each subsequent assessment (T1:T2, t=2.6, p=.02, df=21; T1:T3, t=2.3, p=.04, df=12; T1:T4, t=4.0, p=.04, df=9). A significant dip in MDI scores occurred at approximately 18 and 28 months of age, suggesting a notable decrease in performance specifically during these two periods, after which they appeared to increase. Developmental delays such as language difficulties, characteristic of infant heart transplant recipients, were notable factors responsible for the observed change in MDI scores. These findings iterate the importance of longitudinally assessing changes in neurodevelopmental status instead of presenting collective averages across a wide range of age groups. To better identify and potentially remediate such trends in neurodevelopment, future studies should use longitudinal assessments extending beyond the period examined in this study to replicate and confirm these tentative findings.