Improvements in cognition in patients converting from thrice weekly hemodialysis to nocturnal hemodialysis: a longitudinal pilot study

Subjective cognitive complaints in end-stage renal disease: a systematic review and meta-analysis

Cognitive impairment is common in patients with end-stage renal disease (ESRD) and is associated with compromised quality of life and functional capacity, as well as worse clinical outcomes. Most previous research and reviews in this area were focused on objective cognitive impairment, whereas patients' subjective cognitive complaints (SCCs) have been less well-understood. This systematic review aimed to provide a broad overview of what is known about SCCs in adult ESRD patients. Electronic databases were searched from inception to January 2022, which identified 221 relevant studies. SCCs appear to be highly prevalent in dialysis patients and less so in those who received kidney transplantation. A random-effects meta-analysis also shows that haemodialysis patients reported significantly more SCCs than peritoneal dialysis patients (standardised mean difference -0.20, 95% confidence interval -0.38 to -0.03). Synthesis of longitudinal studies suggests that SCCs remain stable on maintenance dialysis treatment but may reduce upon receipt of kidney transplant. Furthermore, SCCs in ESRD patients have been consistently associated with hospitalisation, depression, anxiety, fatigue, and poorer quality of life. There is limited data supporting a strong relation between objective and subjective cognition but preliminary evidence suggests that this association may be domain-specific. Methodological limitations and future research directions are discussed.

The Impact of Intradialytic Cognitive and Physical Training Program on the Physical and Cognitive Abilities in End-Stage Kidney Disease Patients: A Randomized Clinical Controlled Trial

BACKGROUND

Hemodialysis (HD) patients have lower cognitive functioning and reduced physical fitness than age-matched healthy individuals. Clinicians typically do not recognize the declining cognitive performance in these patients; therefore, cognitive impairment is greatly underestimated and not appropriately treated. This study aimed to evaluate the impact on cognitive function of combining cognitive training with physical exercise and physical performance in HD patients.

METHODS

Using a randomized, single-blinded control design, forty-four HD patients were recruited and randomly assigned to either an intradialytic physical exercise and cognitive training program (EXP group; n = 22; 54% male; 65.7 ± 9.7 years; 77.1 ± 21.9 kg; body mass index 26.8 ± 6.0) or a standard care control group (CON group; n = 21; 77% male; 67.2 ± 12.5 years; 74.2 ± 14.3 kg; body mass index 25.9 ± 3.8). The EXP group performed intradialytic cycling and cognitive training three days per week for 12 weeks. Study outcomes were assessed by the Symbol Digit Modalities Test (SDMT), Montreal Cognitive Assessment (MoCA), 10-repetition sit-to-stand test (10-STS), handgrip strength test (HGS), and stork balance test.

RESULTS

The results showed a significant time*group interaction effect for SDMT (p < 0.001; η2 = 0.267) and MoCA (p < 0.001; η2 = 0.266). Moreover, no significant interaction was observed for 10-STS, HGS, and stork balance test (p > 0.05).

CONCLUSIONS

Our findings suggest that incorporating intradialytic cognitive and physical exercise training could help to improve the functional status of HD patients. The innovative, nonpharmacological, bimodal intervention is cost-effective, safe, and easy to implement during the intradialytic period and offers a potential impact on patients' quality of life and well-being.

Cognitive Function and Vitamin D Status in the Chinese Hemodialysis Patients

OBJECTIVE

Vitamin D insufficiency and the cognitive function decline are both common in patients receiving hemodialysis (HD). The present study evaluated the relation between cognitive function and circulating vitamin D levels in HD patients in Wannan Medical College Affiliated Yijishan Hospital, China.

METHODS

This study was conducted in 80 patients receiving HD in Wannan Medical College Affiliated Yijishan Hospital. To measure cognitive function, Montreal Cognitive Assessment-Basic (MoCA-B) Chinese Version was used. The 25-hydroxyvitamin D [25(OH)D], which is applied to assess vitamin D status, was tested. One-way ANOVA, Tukey post hoc test, and the correlation and regression analysis were used in this study.

RESULTS

Based on the MoCA-B, cognitive function decline (the scores below 26) was present in 28 HD patients, accounting for 35% (28/80). The mean age of these patients is 50.5 ± 10.9 years old. The mean level of 25(OH)D was 16.1 ± 7.3 ng/ml in 80 HD patients. In univariate analysis, there was a significant relationship between MoCA-B score and serum 25(OH)D level (p < 0.05). The level of 25(OH)D was positively correlated with MoCA-B score (r = 0.312, p = 0.023), and the association was independent of demographic and clinical features.

CONCLUSIONS

Vitamin D insufficiency may contribute to cognitive function decline in HD patients. Serum level of 25(OH)D is an independent protective factor of cognitive function in the HD patients.

Effect of Hemodiafiltration Versus Hemodialysis on Cognitive Function Among Patients With End-Stage Renal Disease: A Multicenter Study

Background: Cognitive impairment (CI) and dementia are common in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Their cause is multifactorial. Our study is first to compare the impact of hemodialysis (HD) and online hemodiafiltration (HDF) on patients’ cognitive outcomes.

Methods: This was a cross sectional, multicenter cohort study. Adult ESRD patients aged >18 years on regular high flux HD or online HDF were recruited in the study. Clinical, laboratory, daily activities and cognitive functions assessment were assessed in all the involved individuals.

Results: A total of 241 patients were successfully recruited into the study: 164 treated with high flux HD and 77 treated with HDF. Hypertension and diabetes were the commonest associated comorbidities. 85.9% of patients were functionally independent with no significant difference between those on HD versus HDF. 81.3% of our patients showed different degrees of CI. HDF has no superiority in the improvement of cognitive functions. Age, vitamin D level and haemoglobin (Hb) were the most independent predictors of cognitive function impairment among HD patients.

Conclusions: Cognitive function impairment is a common problem in hemodialysis and is associated with multiple risk factors. HDF showed no beneficial effect over HD. There is no superiority of online HDF versus high flux HD in improving cognitive functions.

Evaluation of the effect of Cooled HaEmodialysis on Cognitive function in patients suffering with end-stage KidnEy Disease (E-CHECKED): feasibility randomised control trial protocol

BACKGROUND

Cognitive impairment is common in haemodialysis (HD) patients and is associated independently with depression and mortality. This association is poorly understood, and no intervention is proven to slow cognitive decline. There is evidence that cooler dialysis fluid (dialysate) may slow white matter changes in the brain, but no study has investigated the effect of cooler dialysate on cognition. This study addresses whether cooler dialysate can prevent the decline in cognition and improve quality of life (QOL) in HD patients.

METHODS

This is a multi-site prospective randomised, double-blinded feasibility trial.

SETTING

Four HD units in the UK.

PARTICIPANTS AND INTERVENTIONS

Ninety HD patients randomised (1:1) to standard care (dialysate temperature 36.5 °C) or intervention (dialysate temperature 35 °C) for 12 months.

PRIMARY OUTCOME MEASURE

Change in cognition using the Montreal Cognitive Assessment (MoCA).

SECONDARY OUTCOME MEASURES

Recruitment and attrition rates, reasons for non-recruitment, frequency of intradialytic hypotension, depressive symptom scores, patient and carers burden, a detailed computerised cognitive test and QOL assessments.

ANALYSIS

mixed method approach, utilising measurement of cognition, questionnaires, physiological measurements and semi-structured interviews.

DISCUSSION

The results of this feasibility trial will inform the design of a future adequately powered substantive trial investigating the effect of dialysate cooling on prevention and/or slowing in cognitive decline in patients undergoing haemodialysis using a computerised battery of neuro-cognitive tests. The main hypothesis that would be tested in this future trial is that patients treated with regular conventional haemodialysis will have a lesser decline in cognitive function and a better quality of life over 1 year by using cooler dialysis fluid at 35 °C, versus a standard dialysis fluid temperature of 36.5 °C. This also should reflect in improvements in their abilities for activities of daily living and therefore reduce carers' burden. If successful, the treatment could be universally applied at no extra cost.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03645733 . Registered retrospectively on 24 August 2018.

Associations between small and middle molecules clearance and the change of cognitive function in peritoneal dialysis

BACKGROUND

Uremic toxins have been suspected as potential contributors for cognitive impairment in peritoneal dialysis (PD) patients. However, associations between the clearance of serum small and middle molecules and the change of cognitive function were not fully explored and then we explored this issue in the present study.

METHOD

A total of clinically-stable 222 patients on PD were enrolled and then followed up for 2 years in this single-center prospective cohort study. Small and middle molecules clearances were examined by urea clearance (Kt/V), creatinine clearance (Ccr) and beta-2 microglobulin (B2M) clearance via dialysate and urine at baseline and after 2 years. Global and specific cognitive impairment were measured at baseline and after 2 years. Modified Mini-Mental State Examination (3MS) was assessed for global cognitive function, trail-making tests A and B for executive function and subtests of the battery for the assessment of neuropsychological status for immediate and delayed memory, visuospatial skills and language ability.

RESULTS

The median of total Kt/V, Ccr and B2M clearance were 1.89, 53.2 l/w/1.73 m2 and 17.5 l/w/1.73 m2, respectively at baseline. The prevalence of global cognitive impairment was 12.3% for 222 patients and 15.4% for the remained 130 patients after 2 years. At baseline, total Kt/V was independently positively associated with delayed memory function. Total and dialysate beta-2 microglobulin clearance was positively associated with 3MS scores and negatively with completion time on trail A after multivariate adjustment. At 2 years, we observed a significant difference in the changing trend of 3MS scores between groups divided by total B2M clearance (P = 0.033), which still maintained to be meaningful after multivariate adjustment (P = 0.024). Patients with total B2M clearance > 19.0 l/w/1.73 m2 got significant improvement on their 3MS scores (P = 0.005). Patients divided by total Kt/V or Ccr were not significantly different in the trends of general and any specific cognitive function during the follow up.

CONCLUSION

The higher middle molecules clearance independently correlated to better performance on general cognitive and executive function in PD patients, which also predict an improvement in general cognitive function during the follow up.

Nocturnal home hemodialysis with low-flow dialysate: Retrospective analysis of the first European patients

INTRODUCTION

Despite mounting evidence that increased frequency and duration of hemodialysis (HD) improves outcomes, less than 1% of HD patients worldwide receive nocturnal hemodialysis (NHD). Many perceived barriers exist to providing NHD and increasing its provision.

METHODS

A retrospective analysis of nocturnal therapy using a low-flow dialysate system in 4 European centers for a minimum of 12 months, with data collected on patient demographics, training times, safety features, medications, and biochemical parameters at baseline and at 6 and 12 months.

FINDINGS

Data were collected on 21 patients, with 12-month analysis available for 20 patients. Mean dialysis duration was 28 hours per week, with most dialysis on an alternate night regimen using 50-60 L of dialysate per session. All vascular access types were represented, and low molecular weight heparin was used as a bolus. All biochemical parameters met European standards, with a trend for improvement in standardized Kt/V, phosphate, hemoglobin, and albumin. There was a significant reduction in phosphate binder usage and a reduction in blood pressure medication. Training time was 9.6 sessions for independence at home, with 2 additional sessions to transition to NHD. Additional safety features included an alarmed drip tray under the cycler and moisture sensors under the venous needle (all patients used dual-cannulation technique). No patient safety events were reported.

DISCUSSION

These data support the use of a low-flow dialysate system for provision of NHD at home. Biochemical parameters were good, medication burden was reduced at 12 months, and all patients received more than double the duration of HD provided in standard in-center units. While patient numbers were small, low-flow dialysis in this cohort was both effective and safe. Use of this alternative HD system could reduce some of the barriers to NHD, increasing the uptake of therapy in Europe, and improving long-term patient outcomes.

Risk of dementia in patients with end-stage renal disease under maintenance dialysis-a nationwide population-based study with consideration of competing risk of mortality

Background

Dementia is prevalent in the end-stage renal disease (ESRD) population. However, it is still not clarified whether ESRD is one of the etiology of dementia or its attributable effect on the cumulative risk of dementia. Meanwhile, the effect of competing risk of mortality should be taken into consideration when performing epidemiologic analyses among populations with high risk of mortality.

Methods

By using the National Health Insurance Research Database (1998–2010), we identified 927,142 non-ESRD individuals and 99,158 ESRD patients to investigate the effect of ESRD on the risk of dementia. Age- and sex-specific incidence rates (IRs) and cumulative incidence rates (CIRs) were first compared between these two cohorts. Competing risk analyses including cause-specific and subdistribution proportional hazards models were then constructed with adjustments for potential confounders.

Results

The overall IR and CIR of dementia were much higher in the ESRD group than in the non-ESRD group (10.73 vs. 1.40 per 1000 person-years and 0.061 vs. 0.017, respectively, both P < 0.0001). Results from the multivariable cause-specific hazard models suggested that ESRD was one of the etiological factors for dementia (cause-specific hazard ratio [csHR] : 2.06 [95% CI : 1.95–2.17]). However, the subdistribution HR (sdHR) of ESRD was 0.51 (95% Cl : 0.49–0.54), which indicated the lower cumulative incidence risk of dementia in ESRD patients. The inverse relationship between csHR and sdHR could be explained by the high mortality rate in the ESRD population. These findings were also essentially consistent across various subgroup analyses according to selected confounders, as well as in the analyses that limited dementia diagnoses made by neurologists or psychologists.

Conclusions

Although ESRD appears directly associated with the risk of dementia, the high competing mortality means that primary prevention of comorbidity associated with dementia may be more effective in reducing overall dementia in the general population, which may also potentially reduce the incidence of ESRD and prevent death from multimorbidity when affected by ESRD.

Electronic supplementary material

The online version of this article (10.1186/s13195-019-0486-z) contains supplementary material, which is available to authorized users.

Qi Fu Yin-a Ming Dynasty Prescription for the Treatment of Dementia

The Traditional Chinese Medicine (TCM) theory that “kidneys give rise to marrow, and the brain is the sea of marrow” has been a guide for the clinical application of kidney, qi and blood tonics for prevention and treatment of dementia and improvement in memory. As low resistance end-organs, both the brain and the kidneys are subjected to blood flow of high volumes throughout the cardiac cycle. Alzheimer’s disease and vascular dementia are two common causes of dementia, and it is increasingly recognized that many older adults with dementia have both AD and vascular pathologies. The underlying molecular mechanisms are incompletely understood, but may involve atherosclerosis, vascular dysfunction, hypertension, type 2 diabetes, history of cardiac disease and possibly, kidney dysfuntion, leading to reduced erythropoietin production, anemia, brain energy deficit and slow excitotoxicity. During the Ming Dynasty, Zhang Jing-Yue used Qi Fu Yin (seven blessings decoction), comprising Panax ginseng, Rehmannia glutinosa, Angelica polymorpha, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube, and Polygala tenuifolia to boost qi and blood circulation, strengthen the heart, and calm the spirit—skillfully linking heart, spleen, kidney, qi, blood and brain as a whole to treat age-related dementia. The purpose of this review is to outline TCM concepts for the treatment of dementia and illustrated with a historical prescription for the treatment of the condition, with the hope that this description may lead to advances in its management.

Understanding the impact of haemodialysis on UK National Health Service patients' well-being: A qualitative investigation

Aims and objectives

While haemodialysis is an effective treatment for end‐stage renal disease, the requirements and restrictions it imposes on patients can be onerous. The aim of this study was to obtain UK National Health Service patients’ perspectives on the challenges arising from haemodialysis with the intention of identifying potential improvements.

Background

Depression rates are particularly high in those with end‐stage renal disease; however, there is limited insight into the range of stressors associated with haemodialysis treatment within the National Health Service contributing to such high rates, particularly those of a cognitive or psychological nature.

Design

A qualitative approach was used to obtain rich, patient‐focused data; one‐to‐one semi‐structured interviews were conducted with twenty end‐stage renal disease at a UK National Health Service centre.

Methods

Patients were interviewed during a typical haemodialysis session. Thematic analysis was used to systematically interpret the data. Codes were created in an inductive and cyclical process using a constant comparative approach.

Results

Three themes emerged from the data: (i) fluctuations in cognitive/physical well‐being across the haemodialysis cycle, (ii) restrictions arising from the haemodialysis treatment schedule, (iii) emotional impact of haemodialysis on the self and others. The findings are limited to predominantly white, older patients (median = 74 years) within a National Health Service setting.

Conclusions

Several of the experiences reported by patients as challenging and distressing have so far been overlooked in the literature. A holistic‐based approach to treatment, acknowledging all aspects of a patient's well‐being, is essential if optimal quality of life is to be achieved by healthcare providers.

Relevance to clinical practice

The findings can be used to inform future interventions and guidelines aimed at improving patients’ treatment adherence and outcomes, for example, improved reliable access to mental health specialists.

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

BACKGROUND AND OBJECTIVES

Cognitive testing is only valid in individuals with sufficient visual and motor skills and motivation to participate. Patients on dialysis usually suffer from limitations, such as impaired vision, motor difficulties, and depression. Hence, it is doubtful that the true value of cognitive functioning can be measured without bias. Consequently, many patients are excluded from cognitive testing. We focused on reasons for exclusion and analyzed characteristics of nontestable patients.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Within the Choice of Renal Replacement Therapy Project (baseline survey: May 2014 to May 2015), n=767 patients on peritoneal dialysis (n=240) or hemodialysis (n=527) were tested with the Trail Making Test-B and the German d2-Revision Test and completed the Kidney Disease Quality of Life Short Form cognition subscale. We divided the sample into patients with missing cognitive testing data and patients with full cognitive testing data, analyzed reasons for nonfeasibility, and compared subsamples with regard to psychosocial and physical metrics. The exclusion categories were linked to patient characteristics potentially associated with missing data (age, comorbidity, depression, and education level) by calculation of λ-coefficient.

RESULTS

The subsamples consisted of n=366 (48%) patients with missing data (peritoneal dialysis =62, hemodialysis =304) and n=401 patients with full cognitive testing data (peritoneal dialysis =178, hemodialysis =223). Patients were excluded due to visual impairment (49%), lack of motivation (31%), and motor impairment (13%). The remaining 8% did not follow instructions, suffered from medical incidents, or had language difficulties. Compared with patients with full cognitive testing data, they were more likely to have depression; be treated with hemodialysis; be older, nonworking, or more comorbid; and experience poorer shared decision making. Reasons for exclusion were not related to levels of age, comorbidity score, depression score, or education level.

CONCLUSIONS

We excluded almost one half of eligible patients from cognitive testing due to visual, motivational, or motor difficulties. Our findings are consistent with exclusion categories reported from the literature. We should be aware that, because of disease-related limitations, conclusions about cognitive functioning in the CKD population may be biased. In the future, nonvisual and nonverbal cognitive testing can be a valuable resource.

Brain-kidney cross-talk: Definition and emerging evidence

Cross-talk is broadly defined as endogenous homeostatic signaling between vital organs such as the heart, kidneys and brain. Kidney-brain cross-talk remains an area with excitingly few publications despite its purported clinical relevance in the management of currently undertreated conditions such as resistant hypertension. Therefore, this review aims to establish an organ-specific definition for kidney-brain cross-talk and review the available and forthcoming literature on this topic.

Supportive Care: Integration of Patient-Centered Kidney Care to Manage Symptoms and Geriatric Syndromes

Dialysis care is often associated with poor outcomes including low quality of life (QOL). To improve patient-reported outcomes, incorporation of the patient's needs and perspective into the medical care they receive is essential. This article provides a framework to help clinicians integrate symptom assessment and other measures such as QOL and frailty scores into a clinical approach to the contemporary supportive care of patients with advanced CKD. This approach involves (1) defining our understanding of kidney supportive care, patient-centered dialysis, and palliative dialysis; (2) understanding and recognizing common symptoms associated with advanced CKD; (3) discussing the concepts of physical function, frailty, and QOL and their role in CKD; and (4) identifying the structural and process barriers that may arise when patient-centered dialysis is being introduced into clinical practice.

Cognitive Changes in Chronic Kidney Disease and After Transplantation

Cognitive impairment is very common in chronic kidney disease (CKD) and is strongly associated with increased mortality. This review article will discuss the pathophysiology of cognitive impairment in CKD, as well as the effect of dialysis and transplantation on cognitive function. In CKD, uremic toxins, hyperparathyroidism and Klotho deficiency lead to chronic inflammation, endothelial dysfunction and vascular calcifications. This results in an increased burden of cerebrovascular disease in CKD patients, who consistently have more white matter hyperintensities, microbleeds, microinfarctions and cerebral atrophy on magnetic resonance imaging scans. Hemodialysis, although beneficial in terms of uremic toxin clearance, also contributes to cognitive decline by causing rapid fluid and osmotic shifts. Decreasing the dialysate temperature and increasing total dialysis time limits these shifts and helps maintain cognitive function in hemodialysis patients. For many patients, kidney transplantation is the preferred treatment modality, because it reverses the underlying mechanisms causing cognitive impairment in CKD. These positive effects have to be balanced against the possible neurotoxicity of infections and immunosuppressive medications, especially glucocorticosteroids and calcineurin inhibitors. A limited number of studies have addressed the overall effect of transplantation on cognitive function. These have mostly found an improvement after transplantation, but have a limited applicability to daily practice because they have only included relatively young patients.

Cognitive changes associated with switching to frequent nocturnal hemodialysis or renal transplantation

Background

It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function in well-dialyzed patients and how this compares to patients who receive a kidney transplant.

Methods

We conducted a multicenter observational study with longitudinal follow-up of the effect on cognitive performance of switching dialysis treatment modality from conventional thrice-weekly hemodialysis to frequent nocturnal hemodialysis, a functioning renal transplant or remaining on thrice-weekly conventional hemodialysis. Neuropsychological tests of memory, attention, psychomotor processing speed, executive function and fluency as well as measures of solute clearance were performed at baseline and again after switching modality. The change in cognitive performance measured by neuropsychological tests assessing multiple cognitive domains at baseline, 4 and 12 months after switching dialysis modality were analyzed using a linear mixed model.

Results

Seventy-seven patients were enrolled; 21 of these 77 patients were recruited from the randomized Frequent Hemodialysis Network (FHN) Nocturnal Trial. Of these, 18 patients started frequent nocturnal hemodialysis, 28 patients received a kidney transplant and 31 patients remained on conventional thrice-weekly hemodialysis. Forty-eight patients (62 %) returned for the 12-month follow-up. Despite a significant improvement in solute clearance, 12 months treatment with frequent nocturnal hemodialysis was not associated with substantial improvement in cognitive performance. By contrast, renal transplantation, which led to near normalization of solute clearance was associated with clinically relevant and significant improvements in verbal learning and memory with a trend towards improvements in psychomotor processing speed. Cognitive performance in patients on conventional hemodialysis remained stable with the exception of an improvement in psychomotor processing speed and a decline in verbal fluency.

Conclusions

In patients on conventional thrice-weekly hemodialysis, receiving a functioning renal transplant was associated with improvement in auditory-verbal memory and psychomotor processing speed, which was not observed after 12 months of frequent nocturnal hemodialysis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0223-9) contains supplementary material, which is available to authorized users.

A 4-month programme of in-centre nocturnal haemodialysis was associated with improvements in patient outcomes

BACKGROUND

Extended periods of haemodialysis (HD) can improve patient outcomes. In-centre nocturnal haemodialysis (INHD) should be explored as a method of offering extended periods of HD to patients unsuitable for or unable to perform home therapy.

METHODS

Ten self-selecting, prevalent HD patients started an INHD programme to assess feasibility and patient satisfaction. Quality-of-life (QOL) measures were evaluated at enrolment and after 4 months of INHD using the EQ-5D, the Hospital Anxiety and Depression Scale (HADS) and the SF-12 questionnaires. Demographic, biochemical and haematological data and data on dialysis adequacy were collected before starting INHD and after 4 months.

RESULTS

Three of the 10 patients failed to complete the 2-week run-in period. Seven patients completed the 4-month programme, with mean dialysis time of 355 ± 43.92 min throughout the period. The EQ-5D visual analogue score improved from 48 ± 16.89 to 72 ± 13.2 (P = 0.003) and the HADS anxiety score decreased from 9 ± 5.83 to 3.57 ± 3.04 (P = 0.029). The urea reduction ratio improved from 71.57 ± 2.29% to 80.43 ± 3.101% (P < 0.001), with improvements in phosphate control, reducing to within the target range from 1.73 ± 0.6 to 1.2 ± 0.2 (P = 0.08). Ultrafiltration (UF) volumes increased during the study from 2000 ± 510 to 2606 ± 343 mL (P = 0.015); there was a significant reduction in mean UF rate adjusted for body weight from 6.47 ± 1.71 to 4.61 ± 1.59 mL/kg/h (P = 0.032). Sensitivity analyses confirmed the significance of these results.

CONCLUSIONS

This single-centre study showed a 4-month programme of extended hours INHD is safe and associated with improvements in QOL measures, decreased UF rates and measures of dialysis adequacy. These data have been used to expand our service and inform the design of future randomized controlled trials to examine medical endpoints.

Pro and con arguments in using alternative dialysis regimens in the frail and elderly patients

In the last decade, an increasing number of patients over 75 years of age are starting renal replacement therapy. Frailty is highly prevalent in elderly patients with end-stage renal disease (ESRD) in the context of the increased prevalence of some ESRD-associated conditions: protein-energy wasting, inflammation, anaemia, acidosis or hormonal disturbances. There are currently no hard data to support guidance on the optimal duration of dialysis for frail/elderly ESRD patients. The current debate is not about starting dialysis or managing conservatory frail ESRD patients, but whether a more intensive regimen once dialysis is initiated (for whatever reasons and circumstances) would improve patients' outcome. The most important issue is that all studies performed with extended/alternative dialysis regimens do not specifically address this particular type of patients and therefore all the inferences are derived from the general ESRD population. Care planning should be responsive to end-of-life needs whatever the treatment modality. Care in this setting should focus on symptom control and quality of life rather than life extension. We conclude that, similar to the general dialysed population, extensive application of more intensive dialysis schedules is not based on solid evidence. However, after a thorough clinical evaluation, a limited period of a trial of intensive dialysis could be prescribed in more problematic patients.

The nature of impairments of memory in patients with end-stage renal disease (ESRD)

Possible impairments of memory in end-stage renal disease (ESRD) were investigated in two experiments. In Experiment 1, in which stimulus words were presented visually, participants were tested on conceptual or perceptual memory tasks, with retrieval being either explicit or implicit. Compared with healthy controls, ESRD patients were impaired when memory required conceptual but not when it required perceptual processing, regardless of whether retrieval was explicit or implicit. An impairment of conceptual implicit memory (priming) in the ESRD group represented a previously unreported deficit compared to healthy aging. There were no significant differences between pre- and immediate post-dialysis memory performance in ESRD patients on any of the tasks. In Experiment 2, in which presentation was auditory, patients again performed worse than controls on an explicit conceptual memory task. We conclude that the type of processing required by the task (conceptual vs. perceptual) is more important than the type of retrieval (explicit vs. implicit) in memory failures in ESRD patients, perhaps because temporal brain regions are more susceptible to the effects of the illness than are posterior regions.

Cognitive function and exercise training for chronic renal disease patients: A literature review

OBJECTIVE

Cognitive impairment is very often noted in patients with Chronic Kidney Disease (CKD). Even though, exercise is considered to be a quantifiable activity that improves cognition in animals and humans, it seems that few studies have examined the relationship between cognitive function and CKD from the perspective of physical activity and cognitive performance. Thus, this evidence based review summarizes the present level of knowledge regarding the effects of exercise training on cognitive function in CKD patients.

DATA SOURCES

A comprehensive literature search was conducted in PubMed and Scopus from May 2014 through June 2014, by using the Cochrane and PRISMA guidelines.

REVIEW METHODS

Eligibility of the studies based on titles, abstracts and full-text articles was determined by two reviewers. Studies were selected using inclusion and exclusion criteria. We included only those studies that: assessed cognitive function in humans and animals using validated neuropsychological methods in chronic renal diseases patients; used exercise training protocols; addressed randomized control trials or controlled trials or clinical trials designed to evaluate cognitive impairment; and articles that were written in English. Studies were excluded when they concerned behavioral approaches and underpowered studies.

RESULTS

According to the current review only a few studies have examined the issue of cognitive function in CKD patients. These studies indicate that these patients often exhibit cognitive impairment, which is highly associated with poor outcomes. It has been supported that exercise training can induce positive changes in brain metabolism favoring better scores in cognitive function in Chronic Kidney Disease patients although the physiological mechanisms, which explain the influence of physical activity on cognition, have focused on changes in neurotransmitters, neurotrophins and vasculature.

CONCLUSION

Systematic exercise training seems to improve cognitive function in Chronic Kidney Disease patients but further research is warranted to further clarify the mechanisms involved.

Cerebral blood flow in patients with peritoneal dialysis by an easy Z-score imaging system for brain perfusion single-photon emission tomography

Cognitive impairment has long been recognized as a complication of chronic kidney disease. However, there is little information available regarding regional cerebral blood flow (rCBF) in patients with peritoneal dialysis (PD). Therefore, we evaluated rCBF using brain single photon emission computed tomography (SPECT). We conducted a cross-sectional study in our hospital. Eighteen consecutive PD patients who could visit the hospital by themselves without any history of stroke were examined by Technetium-99 m-labeled ethylcrysteinate dimer brain SPECT. An easy Z-score imaging system (eZIS) was used to compare rCBF in PD patients with those in age-matched healthy controls. We also evaluated cognitive dysfunction with the mini-mental state examination (MMSE) questionnaire. Only one patient showed an MMSE score of 18 points, and the remaining 14 patients were considered as normal (MMSE ≥ 27), and three patients were considered to have mild cognitive impairment (24 ≤ MMSE ≤ 26). In all patients, rCBF in the posterior cingulated gyri, precunei, and parietal cortices was significantly decreased. The ratio of the reduction of rCBF in each region relative to that of rCBF across the whole brain correlated positively with the PD duration (r = 0.559; P < 0.05). The serum β2-microglobulin level was significantly higher in patients who had a higher ratio of rCBF reduction compared with those with lower ratios. In conclusion, all PD patients in the present study had decreased rCBF irrespective of MMSE scores.

Debate: Should dialysis at home be mandatory for all suitable ESRD patients?: home-based dialysis therapies are the second choice after transplantation

Since their inception in the 1960s, home-based dialysis therapies have been viable alternatives to conventional thrice weekly in center hemodialysis. In spite of this, uptake of these therapies has been steadily declining over past decades with utilization varying globally; dependent on training support, funding models, and prevailing Nephrologist beliefs. In the Australian context, home dialysis (predominantly peritoneal dialysis and extended hours nocturnal hemodialysis) is now again increasing in popularity--with enthusiasm driven not only by evidence of an array of physiological and psychological patient benefit but also significant economic advantage: critical in the current climate where dialysis therapies in Australia take approximately $1 billion dollars per year from the healthcare budget. When assessing the significant advantages of home-based therapies, it is important to consider not only the increasing body of evidence around improved survival but also that for dramatically better health-related quality of life, decreased economic burden and the overall benefits of undertaking treatment in the home. With patient-centered care an increasingly important aspect of our decision making paradigm, home-based dialysis should be considered as the default option in all patients transitioning to renal replacement therapy.

25-vitamin D, 1,25-vitamin D, parathyroid hormone, fibroblast growth factor-23 and cognitive function in men with advanced CKD: a veteran population

Abstract. Cognitive impairment is common in advanced chronic kidney disease (CKD), but little is known about its relation with abnormalities in mineral metabolism. Methods: The longitudinal association between plasma 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)2D), intact parathyroid hormone (iPTH), and fibroblast growth factor-23 (FGF-23) levels and cognitive function was assessed in 605 patients (67 ± 12 years) with advanced CKD not requiring dialysis (n = 247) or end-stage renal disease (ESRD; n = 358) who participated in the Homocysteine Study Cognitive Function Substudy (HOSTCOG)). Cognitive function was assessed using the Telephone Interview for Cognitive Status-modified (TICSm; mean follow-up 3.1 years) and associated with baseline mineral metabolite levels using linear regression analyses. Results: In unadjusted analyses, increasing log 1,25(OH)2D and decreasing log iPTH and FGF-23 levels were associated with worse cognitive status (p < 0.05). In fully adjusted multivariate analyses, the associations were no longer significant. Log 25(OH)D levels were not associated with cognitive function in unadjusted or adjusted analyses. Results were similar when analyzed by tertile or separately within CKD and ESRD groups. Conclusions: These results suggest that mineral metabolism dysregulation does not mediate the impairment in cognitive function common in advanced CKD.

Psychomotor functions at various weeks of chronic renal failure in rats

In chronic renal failure there is a gradual retention of substances in the tissues and body fluids, called as uremic retention toxins, which can bring about a number of biochemical activities in the body. Chronic renal insufficiency also leads to progressive behavioural conflict. Uremic toxins can affect both the central and the peripheral nervous system. Uremic encephalopathy is also associated with problems in cognition and memory. To study the psychomotor functional disorders in rats with progressive chronic renal failure surgical nephrectomy was done by resection method. The animals were grouped into two control groups, Sham control (SC) and normal control (NC) and two uremic groups, moderate uremia (GM) and severe uremia (GS). Psychomotor analysis was done by passive avoidance and open field in these animals at 4, 8, 12, and 16 weeks. After the incubation period, the nephrectomised groups (GM and GS) showed significant changes in exploratory, locomotor and emotional behaviour when compared to the controls (NC and SC). Psychomotor changes involve poor cognition, reduced memory, reduced locomotor activity and decreased exploratory drive and emotional disturbance like increased fear during the initial stages. During the later stages a restless behaviour was noticed, associated with diminished fear.

Patient-reported cognitive functioning and daily functioning in chronic dialysis patients

Subjective cognitive impairment negatively affects daily functioning, health-related quality of life, and health care consumption, and is predictive of future cognitive decline in many patient populations. However, no subjective measures of multidimensional cognitive functioning have been evaluated for dialysis patients. Our purposes were to examine (1) the association between patient-reported (subjective) cognitive functioning and objective cognitive functioning and (2) the relationships between subjective and objective cognitive functioning and everyday functioning of dialysis patients. We used baseline data from an ongoing longitudinal observational study of trajectories in dialysis patients' multidimensional quality of life. One hundred thirty-five patients completed a telephone-based neuropsychological battery (Brief Test of Adult Cognition by Telephone, a measure of objective cognitive functioning), a measure of subjective cognitive functioning (Patient's Assessment of Own Functioning Inventory), and measures of everyday functioning (Activities of Daily Living [ADL] and Instrumental Activities of Daily Living [IADL] scales). After controlling for age and education, there was a modest correlation (r = 0.33, P > 0.001) between subjective and objective cognitive functioning. Multivariate logistic regression models showed subjective, but not objective, cognitive functioning was a significant predictor of both ADLs and IADLs. The findings suggest the potential clinical value of subjective measures of cognitive functioning, not to replace objective measures or diagnostic tests, but rather to optimize the meaningfulness of clinical assessment and management.

Technique survival in home haemodialysis: a composite success rate and its risk predictors in a prospective longitudinal cohort from a tertiary renal network programme

BACKGROUND

Resurgence of interest in home haemodialysis (HHD) is, in part, due to emerging evidence of the benefits of extended HD regimens, which are most feasibly provided in the home setting. Although specific HHD therapy established at home such as nocturnal HD (NHD) has been reported from individual programmes, little is known about overall HHD success.

METHODS

The study included 166 patients who were accepted in the Manchester (UK) HHD training programme through liberal selection criteria. All patients were followed up prospectively until a switch to alternative modality, to include 4528 patient-months of follow-up and about 81 508 HHD sessions during an 8-year period (January 2004-December 2011). Twenty-four patients switched to an alternative modality during the period. Combined technique survival (HHDc) as a composite of training (HHDtr) and at home (HHDhome) was analysed and clinical predictors of HHD modality failure since the commencement of the programme were calculated using Cox regression analysis. Technology-related interruptions to dialysis over a 12-month period and patient-reported reasons for quitting the programme were analysed.

RESULTS

Technique survival at 1, 2 and 5 years was 90.2, 87.4, 81.5% (HHDc) and 98.4, 95.4 and 88.9% (HHDhome) when censored for training phase exits, death and transplantation. The combined HHDc modality switch rate is 1 in 192 patient-months of dialysis follow-up. Age >60 years, diabetes, cardiac failure, unit decrease in Hb and increasing score of age-adjusted Charlson--comorbidity index were significantly associated with technique failure. Significant clinical predictors of HHD technique failure in a multivariate model were diabetes (P = 0.002) and cardiac failure (P = 0.05). The majority (61%) switched to an alternative modality for non-medical reasons. The composite of operator error and mechanical breakdown resulting in temporary HHD technique failure was 0.7% per year.

CONCLUSIONS

HHD training and technique failure rate are low. Technical errors are infrequent too. Diabetes and cardiac failure are associated with significant risk of technique failure. Although absolute rates are low, training failure is proportionally quite significant, highlighting the importance of reporting the composite technique failure rate (to include early HHD training phase) in HHD programmes.

Dialysis therapies in older patients with end-stage renal disease

Each year a large number of older individuals with advanced renal disease are started on chronic dialysis therapy. Life expectancy is estimated at between 2 and 4 years depending on age, comorbidity, and intensity of medical care required in the weeks around the dialysis start time. Survivors remain at high risk of ongoing morbidity. Regarding quality of life, many older patients express regret over having opted for chronic dialysis therapy and subsequently choose to withdraw from treatment, whereas many others maintain a quality of life similar to that of age-matched peers. Early assessment and ongoing comprehensive geriatric assessment is recommended.

Screening for depression: only one piece of the puzzle

In this issue of NDT, van den Beukel et al. from the Netherlands suggest that a 5-item survey questionnaire might be used to replace the Beck Depression Index to screen patients with chronic kidney disease (CKD) for depression. The nephrology community is at a tipping point in terms of the assessment of outcomes, especially among patients on dialysis. Indeed, the entire healthcare community has begun to shift its focus to patient-reported outcomes (PROs), including quality of life, patient satisfaction and the psychosocial determinants of health. Beyond depression, there are a myriad of aspects of psychological distress that include anxiety, worrying, fear of progression of kidney disease and the fear of the future in general, death and dying, hopelessness, questions around the meaning of life and the experience of recurrent psychological and physical trauma through the CKD trajectory. We encourage the community and its researchers to embrace and research PROs, with the aim to create a holistic, patient-centered model of care for patients at all stages of CKD, including those on chronic dialysis and after transplantation, keeping the whole person-and their families-in mind.

Psychometric Analysis of the Patient Assessment of Own Functioning Inventory in Women With Breast Cancer

Background and Purpose: The purpose of this secondary analysis was to examine the reliability and validity of the Patient Assessment of Own Functioning Inventory (PAOFI) in postmenopausal women with early-stage breast cancer before adjuvant therapy. Methods: Data from 259 postmenopausal women with early-stage breast cancer before adjuvant therapy were analyzed. Exploratory factor analysis was used to uncover the PAOFI’s underlying factor structure and reliability coefficients were computed for each subscale. Results: 5 factors measuring perceived cognitive functioning had eigenvalues >1 and accounted for 54% of the extracted variance. Subscale reliability coefficients ranged from .572 to .883. Conclusions: Psychometric evaluation of the PAOFI provided evidence of reliability and construct validity in this population. Additional studies are needed to confirm the 5-factor structure.

Effects of three times weekly eight-hour nocturnal hemodialysis on volume and nutritional status

BACKGROUND

This prospective cohort study compared the changes in body water composition and nutritional parameters measured with multifrequency bioimpedance analysis between 8-hour three times weekly nocturnal hemodialysis (NHD) and 4-hour conventional hemodialysis (CHD) patients.

PATIENTS AND METHODS

55 patients on CHD and 57 patients on NHD were included in the study. Multifrequency bioimpedance analysis was performed at baseline and at the 12th month. The primary outcomes of the study were changes in extracellular water (ECW), fat mass, dry lean mass and phase angle. Secondary outcomes of the study included changes in blood pressure and biochemical parameters related to nutrition and inflammation.

RESULTS

ECW/height values decreased in the NHD group, while they increased in the CHD group. Fat mass, dry lean mass, and serum albumin increased and high sensitive CRP decreased in the NHD group but did not change in the CHD group. When changes in parameters from baseline to the 12th month between the groups were compared, NHD was associated with improvement in volume parameter including ECW/height (difference -0.44 l/m, p < 0.001). Change in blood pressure was not different between the groups, however requirement for antihypertensive medication decreased from 26.5 to 8.5% in the NHD group (p = 0.002). NHD was also associated with increases in fat mass (difference 1.8 kg, p < 0.001), dry lean mass (difference 0.6 kg, p = 0.006), serum albumin (difference 0.19 g/dl, p < 0.001) and cholesterol (difference 18.8 mg, p < 0.001). Phase angle values decreased in the CHD group but did not change in the NHD group (difference between the groups 0.37°, p = 0.04).

CONCLUSION

This study revealed that longer HD facilitates volume control and improves nutritional status.

Effect of more frequent hemodialysis on cognitive function in the frequent hemodialysis network trials

BACKGROUND

Cognitive impairment is common in patients with end-stage renal disease receiving hemodialysis 3 times per week.

STUDY DESIGN

Randomized clinical trial.

SETTING & PARTICIPANTS

218 individuals participating in the Frequent Hemodialysis Network (FHN) Daily Trial and 81 participating in the FHN Nocturnal Trial.

INTERVENTION

The Daily Trial tested in-center hemodialysis 6 times per week versus 3 times per week. The Nocturnal Trial tested home nocturnal hemodialysis 6 times per week versus home or in-center hemodialysis 3 times per week.

OUTCOMES

Cognitive function was measured at baseline, month 4, and month 12. The primary outcome was performance on the Trail-Making Test, Form B, a measure of executive function, and a secondary outcome was performance on the Modified Mini-Mental State Examination, a measure of global cognition. The domains of attention, psychomotor speed, memory, and verbal fluency were assessed in 59 participants in the Daily Trial and 19 participants in the Nocturnal Trial.

RESULTS

We found no benefit of frequent hemodialysis in either trial for the primary cognitive outcome (Daily Trial: OR for improvement, 0.99; 95% CI, 0.59-1.66; Nocturnal Trial: OR, 1.19; 95% CI, 0.48-2.96). Similarly, there was no benefit of frequent hemodialysis in either trial on global cognition, the secondary cognitive outcome. Exploratory analyses in the Daily Trial suggested possible benefits of frequent hemodialysis for memory and verbal fluency, but not for attention and psychomotor speed. Exploratory analyses in the Nocturnal Trial suggested no benefit of frequent hemodialysis on attention, psychomotor speed, memory, or verbal fluency.

LIMITATIONS

Unblinded intervention, small sample.

CONCLUSIONS

Frequent hemodialysis did not improve executive function or global cognition.

Multipass haemodialysis: a novel dialysis modality

Heaf et al. describe the novel multipass system as a most useful application in the setting of daily extended dialysis at home and suggests a number of modifications to our classical dialysis paradigm aimed at reducing water consumption. Their paper shows how continued creative thinking can modify the classical set-up of dialysis to obtain a system which at the same time could be more economical, ecological and simple.

Introduction

Most home haemodialysis (HD) modalities are limited to home use since they are based on a single-pass (SP) technique, which requires preparation of large amounts of dialysate. We present a new dialysis method, which requires minimal dialysate volumes, continuously recycled during treatment [multipass HD (MPHD)]. Theoretical calculations suggest that MPHD performed six times weekly for 8 h/night, using a dialysate bath containing 50% of the calculated body water, will achieve urea clearances equivalent to conventional HD 4 h thrice weekly, and a substantial clearance of higher middle molecules.

Methods

Ten stable HD patients were dialyzed for 4 h using standard SPHD (dialysate flow 500 mL/min). Used dialysate was collected. One week later, an 8-h MPHD was performed. The dialysate volume was 50% of the calculated water volume, the dialysate inflow 500 mL/min−0.5 × ultrafiltration/min and the outflow 500 mL/min + 0.5 × ultrafiltration/min. Elimination rates of urea, creatinine, uric acid, phosphate and β2-microglobulin (B2M) and dialysate saturation were determined hourly.

Results

Three hours of MPHD removed 49, 54, 50, 51 and 57%, respectively, of the amounts of urea, creatinine, uric acid, phosphate and B2M that were removed by 4 h conventional HD. The corresponding figures after 8 h MPHD were 63, 78, 74, 78 and 111%.

Conclusions

Clearance of small molecules using MPHD 6 × 8 h/week will exceed traditional HD 3 × 4 h/week. Similarly, clearance of large molecules will significantly exceed traditional HD and HD 5 × 2.5 h/week. This modality will increase patients' freedom of movement compared with traditional home HD. The new method can also be used in the intensive care unit and for automated peritoneal dialysis.

Cognitive function at 2443 μmol/l creatinine

Background

One hallmark of uremia is the impairment of neuro-cognitive function. Anecdotal clinical description from the early days of chronic dialysis therapy impressively illustrates the improvement of those functions by chronic hemodialysis treatment. Fortunately, today, uremia is only rarely observed in industrialized countries as many patients seek medical/nephrological attention prior to the occurrence of deadly complications of uremia.

Case presentation

We report a rare case of severe uremia and describe the day to day improvement in neuro-cognitive function by dialysis using state of the arte test battery – starting at a serum creatinine of 2443 μmol/l.

Conclusions

Especially executive functions, which are assumed to be localized in the frontal cerebral regions, are impaired in severe uremia and improve remarkably with the correction of severe uremia, i.e. initiation of dialysis.

Intensive hemodialysis: normalizing the "unphysiology" of conventional hemodialysis?

Interest in intensified hemodialysis (HD) regimens is increasing internationally, as there is growing evidence that they are associated with improved outcomes. Appreciation that conventional hemodialysis (CHD), delivered as 4-hour sessions three times a week, is not providing optimal physiological replacement of renal function has led to the development of intensified dialysis therapies. These include long intermittent hemodialysis typically lasting 6-8 hours and delivered three times a week, short daily hemodialysis, providing more frequent sessions 4-7 days a week lasting 2-3.5 hours, and nocturnal hemodialysis, performed 5-7 days a week for 6-8 hours. Studies evaluating outcomes from these programs have indicated superior results to those achieved with CHD, including favorable modifications of cardiovascular risk factors and improvements in a variety of clinical measures. The objective of this review is to present available evidence supporting the hypothesis that in an attempt to provide a "more normal physiology," intensified HD regimens achieve outcomes superior to those historically achieved with CHD.

Nocturnal hemodialysis: analysis following the Frequent Hemodialysis Network trial

The recently concluded Frequent Hemodialysis Network (FHN) trials have demonstrated some striking and unexpected results. Both the daily arm and the nocturnal arm of the trial clearly demonstrated that frequent (daily or nightly) dialysis reduced blood pressure, reduced the number of antihypertensive medications, and reduced serum phosphorous concentration. One of the major questions addressed by these studies was the extent to which left ventricular mass was reduced by frequent dialysis. While the daily FHN trial showed a clear effect of frequent dialysis to reduce left ventricular mass, the nocturnal FHN trial produced inconclusive results. These apparently contradictory results are probably influenced by inadequate power and the somewhat skewed patient selection in the nocturnal arm. Patients in the nocturnal FHN trial had a shorter time on dialysis prior to enrollment, and greater residual renal function than did patients in the daily FHN trial. From a general perspective, it appears that there is minimal difference in the effect on left ventricular mass between frequent daily dialysis and nocturnal dialysis. The FHN trial was not designed to determine the effects of frequent dialysis on mortality. The analyses of this question using retrospective data strongly suggest that frequent dialysis prolongs life. The nephrology community now has the task to develop new ways to deliver improved therapy to patients on dialysis. This task will be challenging as resources for health care are constrained. New approaches to the care of such patients will be needed to realize the important conceptual advances embedded in the results of the FHN trials.

Continuous cognitive improvement 1 year following successful kidney transplant

Successful kidney transplantation was recently shown to lead to improvement in the cognitive performance of patients on chronic dialysis. To examine whether the early cognitive benefits of transplantation continue to develop over time, along with the patients' ongoing recovery, we addressed these questions in a prospective controlled study of 27 dialyzed patients who subsequently received a kidney transplant, 18 dialyzed patients awaiting kidney transplant, and 30 matched controls without kidney disease. Overall, successful kidney transplant contributed to a statistically significant improvement in performance on tests of motor/psychomotor speed, visual planning, memory, and abstract reasoning tested 1 year later. We also studied whether the cognitive performance of patients maintained on dialysis is stable or declines over time and found that it actually declined over this time even in adequately dialyzed patients. Measures of memory functions were particularly affected. This study indicates that the early beneficial effects of transplantation are not transient and were still evident 1 year following transplantation.

Dementia and cognitive impairment in ESRD: diagnostic and therapeutic strategies

Cognitive impairment, including dementia, is a common but poorly recognized problem among patients with end-stage renal disease (ESRD), affecting 16-38% of patients. Dementia is associated with high risks of death, dialysis withdrawal, hospitalization, and disability among patients with ESRD; thus, recognizing and effectively managing cognitive impairment may improve clinical care. Dementia screening strategies should take into account patient factors, the time available, the timing of assessments relative to dialysis treatments, and the implications of a positive screen for subsequent management (for example, transplantation). Additional diagnostic testing in patients with cognitive impairment, including neuroimaging, is largely based on the clinical evaluation. There is limited data on the efficacy and safety of pharmacotherapy for dementia in the setting of ESRD; therefore, decisions about the use of these medications should be individualized. Management of behavioral symptoms, evaluation of patient safety, and advance care planning are important components of dementia management. Prevention strategies targeting vascular risk factor modification, and physical and cognitive activity have shown promise in the general population and may be reasonably extrapolated to the ESRD population. Modification of ESRD-associated factors such as anemia and dialysis dose or frequency require further study before they can be recommended for treatment or prevention of cognitive impairment.

Prevalence and correlates of cognitive impairment in hemodialysis patients: the Frequent Hemodialysis Network trials

BACKGROUND AND OBJECTIVES

Cognitive impairment is common among persons with ESRD, but the underlying mechanisms are unknown. This study evaluated the prevalence of cognitive impairment and association with modifiable ESRD- and dialysis-associated factors in a large group of hemodialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Cross-sectional analyses were conducted on baseline data collected from 383 subjects participating in the Frequent Hemodialysis Network trials. Global cognitive impairment was defined as a score <80 on the Modified Mini-Mental State Exam, and impaired executive function was defined as a score >or=300 seconds on the Trailmaking B test. Five main categories of explanatory variables were examined: urea clearance, nutritional markers, hemodynamic measures, anemia, and central nervous system (CNS)-active medications.

RESULTS

Subjects had a mean age of 51.6 +/- 13.3 years and a median ESRD vintage of 2.6 years. Sixty-one subjects (16%) had global cognitive impairment, and 110 subjects (29%) had impaired executive function. In addition to several nonmodifiable factors, the use of H1-receptor antagonists and opioids were associated with impaired executive function. No strong association was found between several other potentially modifiable factors associated with ESRD and dialysis therapy, such as urea clearance, proxies of dietary protein intake and other nutritional markers, hemodynamic measures, and anemia with global cognition and executive function after adjustment for case-mix factors.

CONCLUSIONS

Cognitive impairment, especially impaired executive function, is common among hemodialysis patients, but with the exception of CNS-active medications, is not strongly associated with several ESRD- and dialysis-associated factors.

Novel Trends in Haemodialysis: Where Are We Heading?

The mortality and morbidity of end-stage renal failure patients undergoing conventional thrice weekly in-centre haemodialysis remain alarmingly high despite continuing advances in haemodialysis technologies and improvements in clinical care. Home haemodialysis continues to be under-utilised in many parts of the world despite the reported benefits. Alternative haemodialysis regimens including longer and/or more frequent dialysis (e.g. nocturnal haemodialysis and short daily haemodialysis), haemodiafiltration and the use of high flux dialysers have become more widespread in recent years as nephrologists struggle to improve the dismal survival figures. Whilst most of the encouraging data have come from observational studies, many randomised controlled trials which will provide more robust data are already underway. This review aims to provide a concise update of the recent and novel trends in haemodialysis. Key words: Haemodiafiltration, High flux dialysis, Home haemodialysis, Nocturnal haemodialysis, Short daily haemodialysis

More intensive hemodialysis

Clinical outcomes have not improved substantially for patients treated with conventional thrice weekly hemodialysis. More intensive hemodialysis regimens, including daily short dialysis, and nocturnal prolonged dialysis show promise to improve morbidity and mortality. Published studies and trials underway examining these therapies are reviewed.