Cognitive Impairment in Chronic Kidney Disease

Objectives: To assess the prevalence of cognitive impairment in persons with chronic kidney disease (CKD) and its relation to the severity of CKD. Design: Cross-sectional study. Setting: University-affiliated ambulatory nephrology and dialysis practices. Participants: Eighty subjects with CKD Stages III and IV not requiring dialysis (CKD) and 80 subjects with CKD Stage V on hemodialysis (end-stage renal disease (ESRD)) with a mean age±standard deviation of 62.5±14.3. Measurements: Three standardized cognitive tests, the Modified Mini-Mental State Examination (3MS), Trailmaking Test B (Trails B), and California Verbal Learning Trial (CVLT). Glomerular filtration rate was estimated in subjects with CKD using the six-variable Modification of Diet in Renal Disease equation. Results: There was a graded relation between cognitive function and severity of CKD. Mean scores on the 3MS, Trails B, and CVLT immediate and delayed recall were significantly worse for subjects with ESRD than for subjects with CKD or published norms (P