Cognitive and academic outcomes in children with chronic kidney disease

Abstract

Background: Few data exist on the cognitive and academic functioning of children with chronic kidney disease (CKD) over the trajectory of their illness. We aimed to determine the association between CKD stages and cognitive and academic performance in children over time.

Methods: We included 53 participants (aged 6-18 years) with CKD stages 1-5 (n = 37), on dialysis (n = 3), or with functioning kidney transplant (n = 22) from three units in Australia from 2015 to 2019. Participants undertook a series of psychometric tests and were invited for repeated assessments annually. We used linear regression and linear mixed models to investigate the effect of CKD stage, adjusted for socioeconomic status.

Results: At baseline, full-scale intelligence quotient (FSIQ) (95%CI) of children on kidney replacement therapy (KRT) was in the low average range (87: 78, 96) and average (101: 95, 108) for children with CKD 1-5. Mean (95%CI) FSIQ, word reading, numerical operations, and spelling scores for children on KRT were 14.3 (- 25.3, - 3.3), 11 (- 18.5, - 3.6), 8.5 (- 17.6, 0.76), and 10 (- 18.6, - 1.3) points lower than children with CKD Stages 1-5. Spelling and numerical operations scores declined by 0.7 (- 1.4, - 0.1) and 1.0 (- 2.0, 0.2) units per year increase in age, regardless of CKD stage.

Conclusions: Children treated with KRT have low average cognitive abilities and lower academic performance for numeracy and literacy compared to both children with CKD 1-5 and to the general population. However, the rate of decline in academic performance over time is similar for children across the full spectrum of CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Keywords: Academic achievement; CKD; Cognition; Paediatric.