Project Title: Cognitive Changes Due to Sickle Cell Disease

Project Lead: Bridgette Carroll, M. S. (PI/mentor: Callahan) 

UNT IRB#: IRB-20-203

Data Source: National Heart, Lung, and Blood Institute (NHLBI) BioLINCC RMDA V02 1d20120806

Study Status: Manuscript in preparation

Study Description: Sickle Cell Disease impacts a significant number of black Americans living in the United States. As a result, the National Heart, Lung, and Blood Institute of the National Institutes of Health (NIH) carried out a multi-site, 10-year prospective cohort study aimed at defining the natural history of sickle cell disease and characterizing its socioeconomic impact. At the time of the study launch, in 1978, the clinical course of sickle cell disease from early childhood to death was poorly understood due to the variability of the manifestation, severity, and complexity of the disease. The chief aim of the original study, known as The Cooperative Study of Sickle Cell Disease (CSSCD) was to furnish knowledge that would spawn the enhancement of the quality of life for patients with sickle cell disease and their families (Gaston & Rosse, 1982).  In advancements since the time of the original study, Sickle Cell Disease has also been associated with significant cerebral damage and cognitive functioning deficits among some individuals (e.g., Hijmans et al., 2011). In light of the significant advances in research over the ensuing years, NIH agreed to provide Ms. Carroll with data from the CSSCD study for the purpose of conducting secondary data analysis focused on the cognitive effects of sickle cell disease (SCD). Data associated with quantitative neuropsychological assessment (e.g., WISC-R, WISC-III, & WJ-R) were used to explore domain specific cognitive deficits in children with sickle cell disease. Analysis of data revealed a significant association between Sickle Cell Disease severity, age, and neurocognitive functioning. Disease severity increased with age and corresponded to greater neurocognitive impairment in the visual-spatial and visual-motor domains. In contrast, within the CSSCD sample, severity of Sickle Cell Disease did not appear to impact working memory and age did not appear to adversely impact verbal-conceptual reasoning. Importantly, family supportiveness (as measured by the Family Environment Scale) appeared to play a neuroprotective role within this sample of children. This study contributed important information regarding Sickle Cell Disease; much of the literature on sickle cell and cognition is focused on adults, resulting in a substantial need for further research on the child population. Additionally, Sickle Cell Disease overwhelmingly effects those who identify as Black or African American, a group that faces many disparities in research and clinical care. This study helps contribute to the knowledge necessary to develop the support essential to helping this marginalized and historically underserved population.