Cognitive impairment is common among patients with chronic kidney disease (CKD) and primarily represents vascular damage (white matter disease) affecting executive functions. This relationship is relevant as CKD patients with cognitive impairment have poorer outcomes when compared to CKD patients without cognitive impairment. Vascular disease is a common pathogenic mechanism for kidney disease and brain function. In a recent study published in AJKD, Kurella Tamura et al evaluated whether cognitive impairment is associated with CKD progression in a cohort of 3900 Chronic Renal Insufficiency Cohort (CRIC) participants with baseline mean estimated glomerular filtration rate (eGFR) of 45 mL/min/1.73m2, followed for 6 years. Contrary to the expectation, cognitive impairment assessed by the Modified Mini-Mental State Examination study was not associated with CKD progression. In particular, Trail Score B, a specific test for executive function was not associated with CKD progression. Reasons for these findings are unclear, but as the authors point out, it is possible that in populations with high competing risk for CKD progression, eGFR and albuminuria remain the most powerful risk factors for CKD progression. These associations should be explored in populations with higher eGFR that are at risk for both CKD progression and vascular dementia. Regardless of the lack of this association, individuals in all stages of CKD are at higher risk for development of cognitive impairment, and this may be a major determinant in their quality of life.
Magdalena Madero, MD
AJKD Blog Contributor