Chronic kidney disease and cognitive impairment

Abstract

Chronic kidney disease (CKD) affects 25% of people aged over 70 years. Cognitive impairment (CI) is frequent in patients with CKD and affects 30% to 60% of patients treated by hemodialysis. The link between CKD and CI is explained by common risk factors, such as hypertension and diabetes, but also by CKD-specific risk factors through vascular, degenerative, and toxic mechanisms. In patients with non-dialyzed CKD, albuminuria is more strongly linked to CI occurrence than glomerular filtration rate. Vascular dementia is the main cause of CI in patients with CKD, but incidence of Alzheimer's disease has also been found higher in patients with end-stage of kidney disease than in the general population. Executive functions, orientation and attention are the most frequently affected cognitive domains in patients with CKD. Occurrence of CI in older patients with CKD could be prevented by controlling blood pressure or the use of anticoagulant drugs in case of atrial fibrillation, which is particularly frequent in patients with CKD, in order to prevent cerebrovascular lesions. Nephrological care could also influence the occurrence of neurological complications. Anticholinesterasic drugs and memantine should be used with caution in patients with CKD, because most of these drugs accumulates in case of low glomerular filtration rate. Due to the poor prognosis of patients with CI and end-stage of kidney disease treated by dialysis or kidney transplantation, a cognitive assessment should be proposed to older patients with severe CKD in order to discuss the initiation and the type of renal replacement therapy with both patients and caregivers.