Cerebral Haemodynamics and Cognitive Impairment in Chronic Haemodialysis Patients: A Pilot Study

Background: Patients with chronic kidney disease (CKD) have a substantially higher risk of developing cognitive impairment (CI) than the general population. Patients with CKD undergoing haemodialysis (HD) treatment also have an elevated risk of developing cerebrovascular and cardiovascular diseases. This study aims to investigate the relationship between the cognitive performance of haemodialysis patients and cerebral and carotid haemodynamic indices. Methods: This study was a non-interventional observational study; the sample consisted of 32 patients (age 65 ± 12 years) undergoing chronic HD treatment. The patients underwent neuropsychological and haemodynamic instrumental investigations, including Supra-Aortic Trunk Echodoppler (SAT) and Transcranial Doppler (TCD). Results: Patients were 17% deficient at Montreal Cognitive Assessment (MoCA), 45% deficient at Frontal Assessment Battery (FAB), 55% deficient at Trail-Making Test-A (TMT-A) and 65% deficient at TMT-B. The TCD investigation detected a decrease in flow (MFV) and an increase in Breath Hold Index (BHI) predominantly in the right cerebral arterial district. The SAT investigation revealed an altered IMT, plaques and the presence of severe carotid stenosis. A strong association between cerebral and carotid indices and cognitive scores was also observed. Correlation analyses reported statistically significant correlations between TMT-A and TMT-B and cerebral flow indices. Conclusions: Among haemodialysis patients, there is a high percentage of cognitive impairment associated and correlated with alterations in cerebral and carotid haemodynamics. Cerebral haemodynamics are a factor to be taken into consideration as a possible pathological mechanism underlying cognitive impairment in haemodialysis.