Cognitive function and advanced kidney disease: longitudinal trends and impact on decision-making

Abstract

Background: Cognitive impairment commonly affects renal patients. But little is known about the influence of dialysis modality on cognitive trends or the influence of cognitive impairment on decision-making in renal patients. This study evaluated cognitive trends amongst chronic kidney disease (CKD), haemodialysis (HD) and peritoneal dialysis (PD) patients. The relationship between cognitive impairment and decision-making capacity (DMC) was also assessed. Methods: Patients were recruited from three outpatient clinics. Cognitive function was assessed 4-monthly for up to 2 years, using the Montreal Cognitive Assessment (MoCA) tool. Cognitive trends were assessed using mixed model analysis. DMC was assessed using the Macarthur Competency Assessment tool (MacCAT-T). MacCAT-T scores were compared between patients with cognitive impairment (MoCA <26) and those without. Results: In total, 102 (41 HD, 25 PD and 36 CKD) patients were recruited into the prospective study. After multivariate analysis, the total MoCA scores declined faster in dialysis compared with CKD patients [coefficient = −0.03, 95% confidence interval (95% CI) = −0.056 to − 0.004; P = 0.025]. The MoCA executive scores declined faster in the HD compared with PD patients (coefficient = −0.12, 95% CI = −0.233 to − 0.007; P = 0.037). DMC was assessed in 10 patients. Those with cognitive impairment had lower MacCAT-T compared with those without [median (interquartile range) 19 (17.9–19.6) versus 17.4 (16.3–18.4); P = 0.049]. Conclusions: Cognition declines faster in dialysis patients compared with CKD patients and in HD patients compared with PD patients. Cognitive impairment affects DMC in patients with advanced kidney disease.

The effect of the interdialytic interval on cognitive function in patients on haemodialysis

“…Cognitive impairments are frequently observed among individuals undergoing haemodialysis (HD) (Griva et al 2010;Lux et al 2010;Song et al 2011;Zammit et al 2015;Foster et al 2016;O'lone et al 2016;Drew et al 2017;Iyasere et al 2017). Such deficits may take the form of memory and attention impairment, reduced psychomotor speed and accuracy, and reduced mental efficiency (O'lone et al 2016;Drew et al 2017).…”

Cerebral ischemia during hemodialysis—finding the signal in the noise

“…Injury to the brain can be assessed either by radiological methods, which provide largely structural information, or validated neurocognitive tests, which provide (arguably more important) functional information . Some but not all observational studies have suggested that patients who undergo maintenance peritoneal rather than hemodialysis have a slower decline in cognitive function, or fewer abnormalities on brain magnetic resonance imaging (MRI) . Increasing hemodialysis vintage has been associated with reductions in baseline cerebral blood flow, frontal lobe oxygenation and cognitive performance, as well as a greater burden of white matter abnormalities on MRI, particularly subtle changes on diffuser tensor imaging (DTI) .…”

“…18 Some but not all observational studies have suggested that patients who undergo maintenance peritoneal rather than hemodialysis have a slower decline in cognitive function, or fewer abnormalities on brain magnetic resonance imaging (MRI). 19,20 Increasing hemodialysis vintage has been associated with reductions in baseline cerebral blood flow, frontal lobe oxygenation and cognitive performance, as well as a greater burden of white matter abnormalities on MRI, particularly subtle changes on diffuser tensor imaging (DTI). [21][22][23] The potential for confounding in these studies is considerable, not least by time and treatment indication.…”

Patterns and characteristics of cognitive functioning in older patients approaching end stage kidney disease, the COPE-study

“…Secondly, patients with cognitive impairment have in general a higher risk for adverse health outcomes such as delirium. Last but not least, it is known that an impaired cognitive functioning can affect decision-making capacity [47] and therefore awareness of cognitive, functional or psychosocial impairment, prior to making a decision on RRT, is of the utmost importance. Information from the geriatric assessment can be taken to the discussions on treatment choice with the patient and family enhancing tailored treatment options for each individual patient.…”