Memory and executive functions in pediatric chronic kidney disease

This study examined the memory and executive functioning of children and adolescents with chronic kidney disease (CKD). The sample included 20 children and adolescents with CKD ranging in age from 7.50 to 19.04 years (M = 13.41, SD = 3.20). Intellectual function for the group was within the low average to average range (M = 89.32, SD = 14.80). Of the participants with CKD, 12 were receiving maintenance dialysis therapy at the time of testing and 8 were managed with conservative therapy. Healthy controls were used as a comparison group (n = 18). This group ranged in age from 7.47 to 18.37 years (M = 12.93, SD = 2.90). Intellectual function was within the average range (M = 112.18, SD = 13.14). All subjects received a comprehensive battery of memory and executive function tasks as part of a larger neuropsychological evaluation. Preliminary examinations of the data revealed a significant difference between the groups in IQ, with the typical group being significantly higher than the CKD group. A multivariate analysis controlling for chronological age revealed significant group differences, with specific differences being noted in all of the memory functions, and the Initiation and Sustaining executive function domains. In all instances the CKD group performed lower than the typical group. The CKD group was particularly deficient in their initiation behaviors within the executive function domain. The groups did not differ on Set-Shifting or Inhibition. These findings remained present even when IQ and chronological age were controlled in the analyses, suggesting the possibility of specific encroachment of renal disease on memory and executive functions beyond the generalized effects of lower IQ. This study represents one of the most extensive examinations of memory and executive functions that has been conducted to date on children and adolescents with CKD. While pervasive dysfunction was not apparent in the children with CKD, they clearly appeared to be at risk for lower IQ as well as inefficiencies in key neurocognitive domains.