Beyond Risk-Based Stratification: Impacts of Processing Speed and Executive Function on Adaptive Skills in Adolescent and Young Adult Cancer Survivors

Purpose: The number of adolescent and young adult (AYA) survivors of childhood cancer is increasing, and the impacts of therapy on their daily lives are not well understood. Adaptive functions are required for age-appropriate interactions and day to day functioning, but are reduced in AYA survivors. Work in other pediatric populations suggests that additional neurocognitive skills may influence adaptive function and, thus, quality of life and personal attainment of AYA cancer survivors. Methods: Retrospective medical records review examined neurocognitive data from 139 AYA survivors. Hierarchical linear regression examined age at diagnosis, use of central nervous system (CNS) radiation, verbal intelligence, processing speed, and executive function as predictors of adaptive functioning domains. Results: AYA survivors exhibited weaknesses in all domains of adaptive functioning compared to normative reference values (Cohen's d=0.660-0.864), as well as in processing speed (Cohen's d=0.791) and metacognitive executive functioning (Cohen's d=0.817). Processing speed and executive function provided substantial improvements in prediction of adaptive functioning beyond that of age at diagnosis and use of CNS-directed radiation therapy. Taken together these variables explained 37.1% of variability in adaptive conceptual skills, 26.1% in adaptive social skills, and 27.1% of adaptive practical skills. Conclusions: Intelligence, processing speed, and executive function significantly contribute to adaptive function scores in AYA cancer survivors and impact domains that are important to self-sufficiency and quality of life. Attention to neurocognitive function in all AYA cancer survivors is recommended in addition to referral for neuropsychological evaluation and tailoring interventions to address executive and adaptive functioning.