Cognitive Testing in Patients with CKD: The Problem of Missing Cases

William M. Feinberg Lecture: Asymptomatic Carotid Stenosis: Current and Future Considerations

Asymptomatic high-grade carotid stenosis is an important therapeutic target for stroke prevention. For decades, the ACAS (Asymptomatic Carotid Atherosclerosis Study) and ACST (Asymptomatic Carotid Surgery Trial) trials provided most of the evidence supporting endarterectomy for patients with asymptomatic high-grade stenosis who were otherwise good candidates for surgery. Since then, transfemoral/transradial carotid stenting and transcarotid artery revascularization have emerged as alternatives to endarterectomy for revascularization. Advances in treatments against atherosclerosis have driven down the rates of stroke in patients managed without revascularization. SPACE-2 (Stent-Protected Angioplasty Versus Carotid Endarterectomy-2), a trial that included endarterectomy, stenting, and medical arms, failed to detect significant differences in stroke rates among treatment groups, but the study was stopped well short of its recruitment goal. CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) will be able to clarify whether revascularization by stenting or endarterectomy remains efficacious under conditions of intensive medical management. Transcarotid artery revascularization has a favorable periprocedural risk profile, but randomized trials comparing it to intensive medical management are lacking. Features like intraplaque hemorrhage on MRI and echolucency on B-mode ultrasonography can identify patients at higher risk of stroke with asymptomatic stenosis. High-grade stenosis with poor collaterals can cause hemispheric hypoperfusion, and unstable plaque can cause microemboli, both of which may be treatable risk factors for cognitive impairment. Evidence that there are patients with carotid stenosis who benefit cognitively from revascularization is presently lacking. New risk factors are emerging, like exposure to microplastics and nanoplastics. Strategies to limit exposure will be important without specific medical therapies.

Peritoneal dialysis versus haemodialysis for people commencing dialysis

BACKGROUND

Peritoneal dialysis (PD) and haemodialysis (HD) are two possible modalities for people with kidney failure commencing dialysis. Only a few randomised controlled trials (RCTs) have evaluated PD versus HD. The benefits and harms of the two modalities remain uncertain. This review includes both RCTs and non-randomised studies of interventions (NRSIs).

OBJECTIVES

To evaluate the benefits and harms of PD, compared to HD, in people with kidney failure initiating dialysis.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies from 2000 to June 2024 using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. MEDLINE and EMBASE were searched for NRSIs from 2000 until 28 March 2023.

SELECTION CRITERIA

RCTs and NRSIs evaluating PD compared to HD in people initiating dialysis were eligible.

DATA COLLECTION AND ANALYSIS

Two investigators independently assessed if the studies were eligible and then extracted data. Risk of bias was assessed using standard Cochrane methods, and relevant outcomes were extracted for each report. The primary outcome was residual kidney function (RKF). Secondary outcomes included all-cause, cardiovascular and infection-related death, infection, cardiovascular disease, hospitalisation, technique survival, life participation and fatigue.

MAIN RESULTS

A total of 153 reports of 84 studies (2 RCTs, 82 NRSIs) were included. Studies varied widely in design (small single-centre studies to international registry analyses) and in the included populations (broad inclusion criteria versus restricted to more specific participants). Additionally, treatment delivery (e.g. automated versus continuous ambulatory PD, HD with catheter versus arteriovenous fistula or graft, in-centre versus home HD) and duration of follow-up varied widely. The two included RCTs were deemed to be at high risk of bias in terms of blinding participants and personnel and blinding outcome assessment for outcomes pertaining to quality of life. However, most other criteria were assessed as low risk of bias for both studies. Although the risk of bias (Newcastle-Ottawa Scale) was generally low for most NRSIs, studies were at risk of selection bias and residual confounding due to the constraints of the observational study design. In children, there may be little or no difference between HD and PD on all-cause death (6 studies, 5752 participants: RR 0.81, 95% CI 0.62 to 1.07; I2 = 28%; low certainty) and cardiovascular death (3 studies, 7073 participants: RR 1.23, 95% CI 0.58 to 2.59; I2 = 29%; low certainty), and was unclear for infection-related death (4 studies, 7451 participants: RR 0.98, 95% CI 0.39 to 2.46; I2 = 56%; very low certainty). In adults, compared with HD, PD had an uncertain effect on RKF (mL/min/1.73 m2) at six months (2 studies, 146 participants: MD 0.90, 95% CI 0.23 to 3.60; I2 = 82%; very low certainty), 12 months (3 studies, 606 participants: MD 1.21, 95% CI -0.01 to 2.43; I2 = 81%; very low certainty) and 24 months (3 studies, 334 participants: MD 0.71, 95% CI -0.02 to 1.48; I2 = 72%; very low certainty). PD had uncertain effects on residual urine volume at 12 months (3 studies, 253 participants: MD 344.10 mL/day, 95% CI 168.70 to 519.49; I2 = 69%; very low certainty). PD may reduce the risk of RKF loss (3 studies, 2834 participants: RR 0.55, 95% CI 0.44 to 0.68; I2 = 17%; low certainty). Compared with HD, PD had uncertain effects on all-cause death (42 studies, 700,093 participants: RR 0.87, 95% CI 0.77 to 0.98; I2 = 99%; very low certainty). In an analysis restricted to RCTs, PD may reduce the risk of all-cause death (2 studies, 1120 participants: RR 0.53, 95% CI 0.32 to 0.86; I2 = 0%; moderate certainty). PD had uncertain effects on both cardiovascular (21 studies, 68,492 participants: RR 0.96, 95% CI 0.78 to 1.19; I2 = 92%) and infection-related death (17 studies, 116,333 participants: RR 0.90, 95% CI 0.57 to 1.42; I2 = 98%) (both very low certainty). Compared with HD, PD had uncertain effects on the number of patients experiencing bacteraemia/bloodstream infection (2 studies, 2582 participants: RR 0.34, 95% CI 0.10 to 1.18; I2 = 68%) and the number of patients experiencing infection episodes (3 studies, 277 participants: RR 1.23, 95% CI 0.93 to 1.62; I2 = 20%) (both very low certainty). PD may reduce the number of bacteraemia/bloodstream infection episodes (2 studies, 2637 participants: RR 0.44, 95% CI 0.27 to 0.71; I2 = 24%; low certainty). Compared with HD; It is uncertain whether PD reduces the risk of acute myocardial infarction (4 studies, 110,850 participants: RR 0.90, 95% CI 0.74 to 1.10; I2 = 55%), coronary artery disease (3 studies, 5826 participants: RR 0.95, 95% CI 0.46 to 1.97; I2 = 62%); ischaemic heart disease (2 studies, 58,374 participants: RR 0.86, 95% CI 0.57 to 1.28; I2 = 95%), congestive heart failure (3 studies, 49,511 participants: RR 1.10, 95% CI 0.54 to 2.21; I2 = 89%) and stroke (4 studies, 102,542 participants: RR 0.94, 95% CI 0.90 to 0.99; I2 = 0%) because of low to very low certainty evidence. Compared with HD, PD had uncertain effects on the number of patients experiencing hospitalisation (4 studies, 3282 participants: RR 0.90, 95% CI 0.62 to 1.30; I2 = 97%) and all-cause hospitalisation events (4 studies, 42,582 participants: RR 1.02, 95% CI 0.81 to 1.29; I2 = 91%) (very low certainty). None of the included studies reported specifically on life participation or fatigue. However, two studies evaluated employment. Compared with HD, PD had uncertain effects on employment at one year (2 studies, 593 participants: RR 0.83, 95% CI 0.20 to 3.43; I2 = 97%; very low certainty).

AUTHORS' CONCLUSIONS

The comparative effectiveness of PD and HD on the preservation of RKF, all-cause and cause-specific death risk, the incidence of bacteraemia, other vascular complications (e.g. stroke, cardiovascular events) and patient-reported outcomes (e.g. life participation and fatigue) are uncertain, based on data obtained mostly from NRSIs, as only two RCTs were included.

A scoping review into the explanations for differences in the degrees of shared decision making experienced by patients

OBJECTIVES

In order to improve the degree of shared decision making (SDM) experienced by patients, it is necessary to gain insight into the explanations for the differences in these degrees.

METHODS

A scoping review of the literature on the explanations for differences in the degree of SDM experienced by patients was conducted. We assessed 21,329 references. Ultimately, 308 studies were included. The explanations were divided into micro, meso, and macro levels.

RESULTS

The explanations are mainly related to the micro level. They include explanations related to the patient and healthcare professionals, the relationship between the patient and the physician, and the involvement of the patient's relatives. On the macro level, explanations are related to restrictions within the healthcare system such as time constraints, and adequate information about treatment options. On the meso level, explanations are related to the continuity of care and the involvement of other healthcare professionals.

CONCLUSIONS

SDM is not an isolated process between the physician and patient. Explanations are connected to the macro, meso, and micro levels.

PRACTICE IMPLICATIONS

This scoping review suggests that there could be more focus on explanations related to the macro and meso levels, and on how explanations at different levels are interrelated.

Methodological challenges and biases in the field of cognitive function among patients with chronic kidney disease

Chronic kidney disease (CKD) affects approximately 850 million people globally and is associated with an increased risk of cognitive impairment. The prevalence of cognitive impairment among CKD patients ranges from 30 to 60%, and the link between CKD and cognitive impairment is partially understood. Methodological challenges and biases in studying cognitive function in CKD patients need to be addressed to improve diagnosis, treatment, and management of cognitive impairment in this population. Here, we review the methodological challenges and study design issues, including observational studies' limitations, internal validity, and different types of bias that can impact the validity of research findings. Understanding the unique challenges and biases associated with studying cognitive function in CKD patients can help to identify potential sources of error and improve the quality of future research, leading to more accurate diagnoses and better treatment plans for CKD patients.

Assessment of hearing and vision impairment in cohort studies collecting cognitive data in older adults

INTRODUCTION

There are no standard practices for considering sensory impairment in studies measuring cognitive function among older adults. Exclusion of participants with impairments may inaccurately estimate the prevalence of cognitive impairment and dementia.

METHODS

We surveyed prospective cohort studies measuring cognitive function in older adults, determined the proportion that excluded participants based on sensory impairment and the proportion that assessed each type of sensory impairment, and described the methods of sensory assessment.

RESULTS

Investigators/staff from 85 (of 192 cohorts) responded; 6 (7%) excluded participants with severe impairment; 80 (94%) measured hearing and/or vision impairment, while 5 (6%) measured neither. Thirty-two (38%) cohorts assessed hearing objectively and 45 (53%) assessed vision objectively.

DISCUSSION

Findings indicate variation in methods used to assess sensory impairment, with potential implications for resource allocation. To ensure equitable inclusion of study participants, consensus is needed on best practices standardized protocols for assessment and accommodations of sensory impairment.

Cognition in chronic kidney disease patients: Evaluation with the Beijing version of the Montreal Cognitive Assessment

Patients with chronic kidney disease (CKD) may undergo cognitive impairment. We aimed to explore the cognition of patients with cognitive impairment (CI) and no cognitive impairment (NCI) respectively and the effect of demographics, estimated glomerular filtration rate (eGFR), number of comorbidities (NCD), and hemoglobin on CI in Chinese patients with CKD at stage 3-5 treated by nondialysis by using the Beijing version of the Montreal Cognitive Assessment (MoCA-BJ). A total of 120 patients with CKD were recruited from the Department of Nephrology at the Affiliated Hospital of Nanjing University of Chinese Medicine at in-patient and out-patient follow up. A logistic regression model was performed to assess the effect of these variables on CI of CKD patients. The results indicated that the CI group was mainly in the decline of visuospatial and executive function, abstraction, and memory, compared with the NCI group. In addition, years of education, eGFR and NCD were found as predictors of CI of CKD patients at stage 3-5. Specifically, lower eGFR, less years of education and more comorbidities were risk predictors of CI.

Adherence to the ambulatory peritoneal dialysis procedure and limitations of care of older adults or their caregivers

BACKGROUND

Continuous Ambulatory Peritoneal Dialysis is an appropriate technique for older adults and its success is mainly based on the correct exchange technique. However, individuals may present barriers to compliance, due to deterioration of physical and cognitive function, depression, and prevalence of visual impairments.

OBJECTIVE AND METHODOLOGY

A descriptive correlational study was conducted to determine the relationship between adherence to the continuous ambulatory peritoneal dialysis procedure and the limitations of care for older adults with chronic renal failure or their caregivers. For convenience, 54 participants from two institutions were selected. A home visit was made at exchange times and a certificate of sociodemographic variables was applied, data such as training days, time of performing the procedure and number of home visits they received were included. Adherence to the procedure was evaluated with a checklist of correctly performed steps in the dialysis technique with Ultra Bag® twin bag equipment (from Baxter). To measure care limitations, we evaluated near visual acuity with Jaeger's equivalent primer, visual fields with the confrontational visual field test, manual sensory dexterity and acuity with Moberg's Pick-Up test, cognitive function using Folstein's MMSE, and depressive symptoms using the CES-D20 instrument.

RESULTS AND CONCLUSIONS

In adherence to the procedure, participants correctly performed an average of 23.42 (SD ± 5.54) steps, which corresponds to 71.72% of the technique. Regarding care limitations, 55.6% presented impaired near visual acuity, 29.6% visual field deficit, 33.3% impaired manual dexterity, 14.8% alteration in manual sensory acuity, 46.3% possible impairment of cognitive function, and 18.5% depressive symptomatology. Participants with greater adherence to the CAPD procedure had better dexterity in the dominant (p = 0.010) and non-dominant (p = 0.010) hand, better sensory acuity of the non-dominant hand (p = 0.023), and greater cognitive function (p = 0.044). It is concluded that the care limitations (manual dexterity, manual sensory acuity, and cognitive function) are related to adherence to the dialytic procedure.

Associations of cardiovascular disease and blood pressure with cognition in hemodialysis patients: The Osaka Dialysis Complication Study

BACKGROUND

Previous studies reported mixed results regarding the contributions of cardiovascular disease (CVD) and blood pressure to cognitive impairment in chronic kidney disease.

METHODS

This was a cross-sectional study in 1213 patients on maintenance hemodialysis from 17 dialysis units in Japan. The main exposures were prior CVD and blood pressure components including systolic (SBP) and diastolic pressure (DBP). The outcome was low cognitive function evaluated with the Modified Mini-Mental State examination (3MS) with a cut-off level of 3MS < 80.

RESULTS

The median age was 67 years, median duration of dialysis was 71 months, 37% were women, 39% had diabetic kidney disease, and 36% had any pre-existing CVD. Median (interquartile range) of 3MS score was 91 (82 to 97), and 240 patients (20%) had 3MS < 80. Logistic regression analysis showed that 3MS < 80 was associated with the presence of any prior CVD, particularly prior stroke. 3MS < 80 was associated with lower DBP but not with SBP. When patients were stratified by the presence of prior stroke, lower DBP, higher age, and lower education level were factors associated with 3MS < 80 in both subgroups. In the subgroup of patients without prior stroke, diabetic kidney disease was an additional factor associated with 3MS < 80. CVDs other than stroke were not associated with 3MS in either subgroup.

CONCLUSIONS

Prior stroke and lower DBP were associated with 3MS < 80 in hemodialysis patients. These findings support the hypothesis that these vascular factors contribute to low cognitive performance in patients undergoing hemodialysis.

The effects of dialysis modality choice on cognitive functions in patients with end-stage renal failure: a systematic review and meta-analysis

INTRODUCTION

Cognitive dysfunction is a major consequence of end-stage renal disease (ESRD) and has further detrimental effects on both functionality and the quality of life for patients. While peritoneal dialysis is generally advocated in ESRD, there is a substantial knowledge gap about the differential effects of chronic dialysis modalities on cognitive dysfunction and decline. The aim of this meta-analysis is to evaluate cognitive function in peritoneal dialysis versus hemodialysis patients.

METHODS

We performed a systematic review in different databases to identify studies that assessed the effect of different dialysis modalities on cognitive functions. Inclusion criteria for our meta-analysis were all studies that compared the effects of peritoneal dialysis on cognitive functions compared to intermittent hemodialysis. The data collected were the name of the first author, journal title, year of publication, country where the study was conducted, number of patients in the peritoneal dialysis and hemodialysis arms and methods of assessment of cognitive functions.

RESULTS

Out of 2769 abstracts reviewed in different databases, 11 papers were included in our meta-analysis. Altogether, 195,774 patients were included in the final analysis. The forest plot analysis of the rate of cognitive impairment in different dialysis modalities showed decreased risk of cognitive impairment in the peritoneal dialysis population compared to hemodialysis patients (relative risk = 0.634, confidence interval ranges from 0.508 to 0.790). There was evidence of significant heterogeneity among studies with p < 0.0001 and I² = 85.5%. The sensitivity analysis limited to studies on patients younger than 65 years of age showed similar results (relative risk = 0.516; 95% confidence intervals: 0.379-0.704).

CONCLUSION

Patients on peritoneal dialysis demonstrated a lower odd of cognitive dysfunction compared to those on hemodialysis. Future prospective studies should assess cognitive decline as a meaningful outcome in dialysis patients.

Cognitive impairment and associated risk factors in older adult hemodialysis patients: a cross-sectional survey

The clinical epidemiological features of cognitive impairment in Chinese older adult patients undergoing hemodialysis are not clear, we aimed to identify the extent and patterns of cognitive impairment among those patients. We conducted a cross-sectional study of 613 hemodialysis patients aged 50 to 80 from 11 centers in Beijing. A neuropsychological battery of 11 tests covering domains of attention/processing speed, executive function, memory, language, and visuospatial function was applied, patients were classified as none, mild, or major cognitive impairment according to the fifth version of the Diagnostic and Statistical Manual of Mental Disorders criteria for cognitive impairment. Compared with Chinese population norms, 37.2% of the participants had mild cognitive impairment, 43.7% had major cognitive impairment. Memory and language were the most severe impaired domains in the mild cognitive impairment group, attention and visuospatial function domains were the most serious impaired domains in the major cognitive impairment group. Concomitant impairment across multiple cognitive domains was common. Factors associated with major cognitive impairment included age, education level, history of stroke and hypertension, dialysis vintage, and single-pool Kt/V. There is a high frequency of cognitive impairment in Chinese older adult hemodialysis patients, with varying severity and concomitant impairment across multiple domains.

Real-time Noninvasive Monitoring of Intracranial Fluid Shifts During Dialysis Using Volumetric Integral Phase-Shift Spectroscopy (VIPS): A Proof-of-Concept Study

BACKGROUND

Cerebral edema, which is associated with increased intracranial fluid, is often a complication of many acute neurological conditions. There is currently no accepted method for real-time monitoring of intracranial fluid volume at the bedside. We evaluated a novel noninvasive technique called "Volumetric Integral Phase-shift Spectroscopy (VIPS)" for detecting intracranial fluid shifts during hemodialysis.

METHODS

Subjects receiving scheduled hemodialysis for end-stage renal disease and without a history of major neurological conditions were enrolled. VIPS monitoring was performed during hemodialysis. Serum osmolarity, electrolytes, and cognitive function with mini-mental state examination (MMSE) were assessed.

RESULTS

Twenty-one monitoring sessions from 14 subjects (4 women), mean group age 50 (SD 12.6), were analyzed. The serum osmolarity decreased by a mean of 6.4 mOsm/L (SD 6.6) from pre- to post-dialysis and correlated with an increase in the VIPS edema index (E-Dex) of 9.7% (SD 12.9) (Pearson's correlation r = 0.46, p = 0.037). Of the individual determinants of serum osmolarity, changes in serum sodium level correlated best with the VIPS edema index (Pearson's correlation, r = 0.46, p = 0.034). MMSE scores did not change from pre- to post-dialysis.

CONCLUSIONS

We detected an increase in the VIPS edema index during hemodialysis that correlated with decreased serum osmolarity, mainly reflected by changes in serum sodium suggesting shifts in intracranial fluids.

The assessment of cognitive function in older adult patients with chronic kidney disease: an integrative review

INTRODUCTION

Chronic kidney disease (CKD) is a common chronic condition in older adults that is associated with cognitive decline. However, the exact prevalence of cognitive impairment in older adults with CKD is unclear likely due to the variety of methods utilized to assess cognitive function. The purpose of this integrative review is to determine how cognitive function is most frequently assessed in older adult patients with CKD.

METHODS

Five electronic databases were searched to explore relevant literature related to cognitive function assessment in older adult patients with CKD. Inclusion and exclusion criteria were created to focus the search to the assessment of cognitive function with standardized cognitive tests in older adults with CKD, not on renal replacement therapy.

RESULTS

Through the search methods, 36 articles were found that fulfilled the purpose of the review. There were 36 different types of cognitive tests utilized in the included articles, with each study utilizing between one and 12 tests. The most commonly utilized cognitive test was the Mini Mental State Exam (MMSE), followed by tests of digit symbol substitution and verbal fluency. The most commonly assessed aspect of cognitive function was global cognition.

DISCUSSION

The assessment of cognitive function in older adults with CKD with standardized tests is completed in various ways. Unfortunately, the common methods of assessment of cognitive function may not be fully examining the domains of impairment commonly found in older adults with CKD. Further research is needed to identify the ideal cognitive test to best assess older adults with CKD for cognitive impairment.

Screening of Cognitive Impairment in the Dialysis Population: A Scoping Review

BACKGROUND

Cognitive impairment in end-stage kidney disease patients on dialysis is increasingly common. This study aimed to review the practice of screening and to evaluate the evidence on cognitive impairment prevalence in this population.

METHODS

This scoping review of studies summarises the evidence on cognitive impairment in dialysis populations. The search included the Medline, CINAHL, Embase, PsycINFO, PubMed, and Cochrane Library databases for English-language articles published between 2000 and 2015. A total of 46 articles were reviewed.

RESULTS

The studies were of prospective observational design, with the majority conducted in the haemodialysis population. The reported prevalence of cognitive impairment ranged from 6.6 to 51%. Three screening tools were consistently used.

CONCLUSION

While cognitive impairment is recognised in the dialysis population, there is paucity of screening data. The design of prospective comparisons ideally includes established screening instruments, particularly the Montreal Cognitive Assessment, to determine the optimal results for this population. Translation of established screening tools to increase the inclusion of people from other cultural and language groups is required. Regular screening can enhance the timing to introduce home-based care support and advance care planning discussions.

Peritoneal dialysis is associated with better cognitive function than hemodialysis over a one-year course

Impaired cognitive functioning in patients with end-stage renal disease may reduce their capabilities to adhere to complex medical or dietary regimens and to fully participate in medical decisions. With decreasing renal function, cognitive abilities are likely to decline, with cognitive dysfunction improving after initiation of dialysis and even being generally reversible after successful renal transplantation. However, little is known about cognitive changes particularly regarding different treatment modalities. To gain further insight into this, we focused on a one-year course of cognitive functions, comparing peritoneal to hemodialysis patients. Within the CORETH-project, two validated neurocognitive tests, assessing executive functioning (Trail Making Test-B) and attention (d2-Revision-Test) and the self-reported Kidney Disease Quality of Life Short Form Cognitive Function-subscale, were administered to 271 patients at baseline and after one year. Subsamples were matched by propensity score, adjusting for age, comorbidity, education, and employment status for 96 hemodialysis and 101 peritoneal dialysis patients. The effects of time and treatment modality were investigated, controlling for well-known confounders. Both tests revealed improvement over one year. Peritoneal dialysis was associated with better outcomes than hemodialysis at baseline and follow-up, but comparability between groups may be limited. The opposite pattern applied to self-reporting. Hemodialysis patients had to be excluded from cognitive testing more often than peritoneal dialysis patients. As such, the number of exclusions may have biased the findings, limiting generalizability. Thus, our findings suggest an improvement of cognitive functioning and support previous indications for peritoneal dialysis being associated with better cognitive functions during a one-year course than hemodialysis.

Pulse-wave velocity is associated with cognitive impairment in haemodialysis patients

Chronic kidney disease (CKD) is common, its prevalence increasing with age. Cognitive impairment is common in the elderly, in CKD and in those on maintenance haemodialysis. As cognitive impairment is the precursor to dementia, the identification of reversible risk factors for cognitive decline is the key to reducing dementia risk. Arterial stiffness is one such potential risk factor. It is independently associated with cardiovascular outcome in dialysis patients. Importantly, the recent demonstration of an independent association between arterial stiffness and cognitive impairment in these patients suggests that vascular stiffness might be potentially causative in the development of cognitive impairment and also be an opportune target for interventions. Whether unstiffening of blood vessels in patients on maintenance haemodialysis can reduce the incidence of cognitive impairment or indeed slow its progression to dementia, remain unanswered questions. In this issue of the Clinical Science, Angermann and colleagues present thought-provoking data related to cognitive impairment in haemodialysis patients.