The Role of Dialysis in the Pathogenesis and Treatment of Dementia

Dearbhla M. Kelly


Nephrol Dial Transplant. 2019;34(7):1080-1083. 

In This Article

Biomarkers of the Strain Vessel Hypothesis

The 'strain vessel hypothesis' has been proposed as a possible mechanism for cerebrorenal connections.[13] Albuminuria may be an early sign of vascular and hypertensive damages imposed on 'strain vessels' such as cerebral perforating arteries and juxtamedullary afferent arterioles that have to maintain strong vascular tone in order to provide large pressure gradients from the parent vessels to the capillaries. Thus, 'strain vessel injuries' may explain the link between vascular damage and microalbuminuria in the kidney and cerebrovascular disease.

As part of the randomized clinical trial of blood pressure targets in older adults with cardiovascular disease, CKD or high cardiovascular disease risk, participants in the Systolic Blood Pressure Intervention Trial (SPRINT)-Memory and Cognition in Decreased Hypertension substudy underwent detailed neurocognitive testing.[14] In adjusted analyses, higher albumin:creatinine ratio was associated with worse global cognitive function, executive function, memory, attention and large abnormal white matter volume. The authors conclude that albuminuria identifies a higher burden of abnormal brain white matter disease and that vascular disease may mediate these relationships.

Cognitive impairment with abnormal structural neuroimaging is common in CKD patients, particularly in ESKD. In a study of 60 PD patients, 30 HD and 30 non-dialysed Stages 3–5 CKD patients without history of stroke, cognitive impairment was significantly more severe in dialysis patients than in non-dialysed patients.[15] In all groups, higher white matter grade, ventricular grade and hippocampal atrophy were significantly associated with global cognitive impairment, with hazard ratios of 1.80, 1.67 and 2.49, respectively. HD patients had more severe white matter hyperintensity, sulcal and ventricular atrophy, and small vessel infarcts than other patients. Although HD patients had more severe neuroimaging abnormalities, dialysis modality showed no association with cognitive impairment in this study.