K CHEN1,2, M DIDSBURY1,2, A V ZWIETEN1,2, M HOWELL1,2, S KIM1, A TONG1,2, B BARTON3, S LAH4, J LORENZO3, G STRIPPOLI5, S PALMER6, A TEIXERA-PINTO2, F MACKIE7, S MCTAGGART8, A WALKER9, T KARA10, J CRAIG1,2, G WONG1,2,11
1Centre for Kidney Research, Kids Research Institute, The Children’s Hospital at Westmead, Sydney, Australia; 2Sydney School of Public Health, The University of Sydney, Sydney, Australia; 3Children’s Hospital Education Research Institute, The Children’s Hospital at Westmead, Sydney, Australia; 4School of Psychology, The University of Sydney, Sydney, Australia, and the ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia; 5Department of Emergency and Organ Transplantation, University of Bari, Italy; 6Department of Medicine, University of Otago Christchurch, New Zealand; 7Department of Renal Medicine, Sydney Children’s Hospital at Randwick, Sydney, Australia; 8Child & Adolescent Renal Service, Children’s Health Queensland, Brisbane, Australia; 9Department of Renal Medicine, The Royal Children’s Hospital, Melbourne, Australia; 10Department of Nephrology, Starship Children’s Hospital, Auckland, New Zealand; 11Centre for Transplant and Renal Research, Westmead Hospital, Sydney, Australia
Aim: To examine global and domain-specific cognition and educational outcomes in children and adolescents with chronic kidney disease (CKD), and whether these outcomes vary with CKD stage.
Background: An association has been established between cognitive function and CKD stage in adults, but not in children, though reduced cognition may negatively impact on educational outcomes.
Methods: We conducted a systematic review comprising observational studies of patients with CKD aged 21 years or younger, and standardised measures of neurocognitive or educational outcomes, including intelligence, attention, executive function, language, memory, and academic skills. MEDLINE, Embase, and PsycINFO were searched from database inception to December 2016, with no language restrictions.
Results: Thirty-four studies (25 cross-sectional, 9 cohort; n=3,086) were eligible. The global cognition (full-scale intelligence quotient, FSIQ) of children with CKD was classified as average with an overall mean 92.7 (standard deviation 16.2). Compared to the general population, the mean differences (95%CI) in FSIQ were -10.5 (-13.2, -7.72) (all CKD stages, n=758), -9.39 (-12.6, -6.18) (pre-dialysis, n=582), -16.2 (-33.2, 0.86) (dialysis, n=23) and -11.2 (-17.8, -4.50) (transplant, n=153). Children with CKD also had lower scores in the domains of executive function and memory (verbal and visual), compared to the general population. Compared to children without CKD, the mean difference in academic skills ranged from -15.7 to 3.50 for mathematics, -15.5 to 3.10 for reading, and -15.0 to -1.68 for spelling.
Conclusions: Children with CKD may have below average intellectual functioning and academic skills compared to the general population, with mild deficits observed across executive function, visual and verbal memory. While patterns of impairment are unclear across cognitive domains, it appears that children on dialysis may be at greatest disadvantage.