Cognitive Abilities Moderate the Effect of Disease Severity on Health-Related Quality of Life in Pediatric Sickle Cell Disease.

ABSTRACT

Objective: Complications that can arise from sickle cell disease (SCD) have the potential to negatively affect health-related quality of life (HRQL). SCD manifests in varying degrees of severity, but effects on HRQL are not uniform. Cognitive abilities influence HRQL in other pediatric groups, potentially through variability in treatment adherence and psychological coping. This study examined the effect of SCD severity on HRQL and explored cognitive abilities as a moderator of this relationship. Methods: A total of 86 children and adolescents with SCD (ages 7-16 years) completed a cognitive assessment (Wechsler Scale of Intelligence for Children, Fifth Edition), and primary caregivers rated their child's SCD severity and HRQL (PedsQL Sickle Cell Disease Module). A hierarchical linear regression was conducted to evaluate the interactive effect of SCD severity and cognitive functioning on HRQL. Results: Caregiver-rated SCD severity predicted HRQL and cognitive abilities interacted with disease severity to influence HRQL. Youth with milder SCD and cognitive abilities in the average range or higher demonstrated significantly better HRQL compared with youth with mild SCD but below average cognitive abilities. Youth with more severe disease appeared to exhibit similarly low levels of HRQL, with only a minimal influence of cognitive abilities. Conclusions: Cognitive factors modify the effect of SCD severity on HRQL, particularly among youth with milder forms of SCD. Future studies are warranted to clarify the role of cognitive abilities in determining HRQL. Clinicians should monitor youth with milder forms of SCD and limited cognitive abilities for worsening HRQL and opportunities to provide support around disease self-management.