Neuropsychological functioning in preschool-aged children with sickle cell disease

The purpose of this study was to examine the association of illness-related and psychosocial factors with neuropsychological functioning in preschool-aged children with sickle cell disease (SCD). The following hypotheses were proposed: (1) children with SCD would perform less well than normative groups on neuropsychological measures, (2) they would perform relatively less well on measures of Memory/Attention as compared to other domains, and (3) psychosocial risk factors would predict variability in neuropsychological performance over and above that predicted by illness-related factors. Methods: Participants were 22 children with SCD, ages 3-5 years, without overt stroke. The following neuropsychological domains were assessed: general intellectual functioning, language, memory/attention, visuospatial/visuoconstructional, and motor/visuomotor. Primary caregivers completed an information form, the Family Environment Scale, the Pediatric Inventory for Parents, and a questionnaire regarding home environment. Information about illness severity was gathered from medical charts and data collected as part of a longitudinal study from which all children were recruited. Results: Mean standard scores across domains ranged from 87.7 to 94.9. The sample performed significantly lower than the normative sample on Full Scale IQ and several other domains. Although the sample performed statistically better on the Memory/Attention domain than other domains, these differences did not seem clinically meaningful. Correlation analyses indicated that disease severity was not significantly related to neuropsychological functioning. However, maternal education/family income was correlated with most neuropsychological domains and accounted for a large portion of the variance in regression analyses. Other psychosocial variables of interest included the PIP difficulty total score, number of children living in the home, and hours per week in school/day care. Conclusions: This study highlights the importance of identifying neuropsychological effects of SCD in preschool-aged children. Results of this study suggest that the disease process may not have a significant effect on neurological integrity in young children without overt stroke. At this age, psychosocial factors seem to be appropriate targets for intervention, with the goal of promoting cognitive development. Despite several limitations that may have affected the results, the study provides support for early identification of at-risk children in order to decrease neuropsychological morbidity in SCD.