Cognitive impairment in patients on dialysis: can we prevent it?

Chronic kidney disease (CKD) is among the leading causes of morbidity and mortality as it affects more than 10% of the global adult population. Cognitive impairment has a positive correlation with the stage of CKD. It has been recorded in more than half of CKD patients undergoing kidney replacement therapy. The assessment of cognitive function in dialysis patients presents challenges due to various patient limitations. Such a common debilitating comorbidity of CKD has no approved treatment option, highlighting the importance of preventive measures and screening modalities. Erythropoietin therapy, exercise training, cognitive stimulation or behavioral therapies, alterations in dialysis frequency, dialysate cooling and kidney transplantation have been proposed as potential preventive and/or therapeutic options with variable efficiency at a clinical level. Regular screening, such as yearly, for cognitive impairment in maintenance dialysis patients is not only beneficial for timely and accurate diagnosis but also crucial for effective management and improved patient care. However, current practices face challenges, including the absence of validated tools specific for kidney failure and complications arising from patient conditions.

The association of cognition with protein energy wasting and synaptic transmission in chronic kidney disease

INTRODUCTION

In recent years, consciousness impairment in patients with end-stage renal disease (ESRD) has been paid more and more attention, but the cause and mechanism of consciousness state change is not clear.

METHODS

As the hippocampus played a crucial role in consciousness, we explored the pathological and electrophysiological changes in chronic kidney disease (CKD) mouse hippocampus.

RESULTS

Whole-cell recordings in hippocampal neurons showed that miniature excitatory postsynaptic current (mEPSC) frequency decreased, but the amplitude was unaltered in CKD_8w mice. In addition, α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor-mediated EPSCs (AMPAR-EPSCs) and N-methyl-D-aspartic acid receptor-mediated EPSCs (NMDAR-EPSCs) in hippocampal Schaffer collateral-CA1 synapses displayed a significant decline in CKD_8w mice. Although the ratio of AMPAR-/NMDAR-EPSCs did not change, the paired-pulse ratio (PPR) in CKD_8w mice increased. Intriguingly, the mEPSC frequency and AMPAR-/NMDAR-EPSCs amplitudes were positively associated with body weight, and the mEPSC frequency was negatively correlated with serum creatinine in CKD_8w mice, indicating a potential correlation between cognition and nutritional status in patients with CKD. To confirm the above hypothesis, we collected the clinical data from multiple hemodialysis centers to analyze the correlation between cognition and nutritional status.

CONCLUSION

Our analysis indicated that protein energy wasting (PEW) was a possible independent risk factor for consciousness dysfunction in maintenance hemodialysis (MHD) patients. Our results provided a more detailed mechanism underlying the cognitive impairment (CI) in ESRD patients at the synaptic level. Last but not least, our results showed that PEW was a probable new independent risk factor for CI in cases with ESRD.

Epidemiology of peritoneal dialysis outcomes

Peritoneal dialysis (PD) is an important home-based treatment for kidney failure and accounts for 11% of all dialysis and 9% of all kidney replacement therapy globally. Although PD is available in 81% of countries, this provision ranges from 96% in high-income countries to 32% in low-income countries. Compared with haemodialysis, PD has numerous potential advantages, including a simpler technique, greater feasibility of use in remote communities, generally lower cost, lesser need for trained staff, fewer management challenges during natural disasters, possibly better survival in the first few years, greater ability to travel, fewer dietary restrictions, better preservation of residual kidney function, greater treatment satisfaction, better quality of life, better outcomes following subsequent kidney transplantation, delayed need for vascular access (especially in small children), reduced need for erythropoiesis-stimulating agents, and lower risk of blood-borne virus infections and of SARS-CoV-2 infection. PD outcomes have been improving over time but with great variability, driven by individual and system-level inequities and by centre effects; this variation is exacerbated by a lack of standardized outcome definitions. Potential strategies for outcome improvement include enhanced standardization, monitoring and reporting of PD outcomes, and the implementation of continuous quality improvement programmes and of PD-specific interventions, such as incremental PD, the use of biocompatible PD solutions and remote PD monitoring.

The use of peritoneal dialysis (PD) can be advantageous compared with haemodialysis treatment, although several barriers limit its broad implementation. This review examines the epidemiology of peritoneal dialysis (PD) outcomes, including clinical, patient-reported and surrogate PD outcomes.

Peritoneal dialysis (PD) has distinct advantages compared with haemodialysis, including the convenience of home treatment, improved quality of life, technical simplicity, lesser need for trained staff, greater cost-effectiveness in most countries, improved equity of access to dialysis in resource-limited settings, and improved survival, particularly in the first few years of initiating therapy.

Important barriers can hamper PD utilization in low-income settings, including the high costs of PD fluids (owing to the inability to manufacture them locally and the exorbitant costs of their import), limited workforce availability and a practice culture that limits optimal PD use, often leading to suboptimal outcomes.

PD outcomes are highly variable around the world owing in part to the use of variable outcome definitions, a heterogeneous practice culture, the lack of standardized monitoring and reporting of quality indicators, and kidney failure care gaps (including health care workforce shortages, inadequate health care financing, suboptimal governance and a lack of good health care information systems).

Key outcomes include not only clinical outcomes (typically defined as medical outcomes based on clinician assessment or diagnosis) — for example, PD-related infections, technique survival, mechanical complications, hospitalizations and PD-related mortality — but also patient-reported outcomes. These outcomes are directly reported by patients and focus on how they function or feel, typically in relation to quality of life or symptoms; patient-reported outcomes are used less frequently than clinical outcomes in day-to-day routine care.

[Long-term physical and psychological consequences of chronic kidney disease]

Aufgrund der verbesserten Behandlungsoptionen können Patient:innen mit chronischen Nierenerkrankungen heute deutlich länger überleben als noch vor 10 Jahren. Das Überleben ist für die Betroffenen jedoch immer mit einem Verlust an Lebensqualität verbunden. In diesem Beitrag wird eine kurze Übersicht über die körperlichen und psychischen Erkrankungsfolgen, Begleiterkrankungen und Therapienebenwirkungen bei chronischen Nierenerkrankungen gegeben. Auf bisher bekannte Auswirkungen der COVID-19-Pandemie wird hingewiesen. Abschließend wird aufgezeigt, wie die Langzeitbehandlung weiterentwickelt werden sollte, um die Lebensqualität der Patient:innen zu erhöhen.

Funktionseinschränkungen der Niere haben aufgrund der Kontamination des Blutes mit harnpflichtigen Substanzen (Urämie) schwere Auswirkungen auf den Gesamtorganismus. Zusätzlich sind die Patient:innen von Nebenwirkungen betroffen, die im Zusammenhang mit der medikamentösen Therapie, Dialyse oder Nierentransplantation auftreten können. Patient:innen und Angehörige sind einer großen psychischen Belastung ausgesetzt. Infektionen mit SARS-CoV‑2 können die Nierenfunktion beeinträchtigen und auch die Prognose einer bereits bestehenden Erkrankung verschlechtern.

Die ganzheitliche Versorgung der Patient:innen mit chronischen Nierenerkrankungen muss neben der medizinischen Versorgung auch die psychologischen und psychosozialen Aspekte berücksichtigen. Nephrologie und Psychonephrologie müssen Hand in Hand weiterentwickelt werden, um die medizinische Versorgung und Lebensqualität der betroffenen Patient:innen zu verbessern.

Cerebral microbleeds and their influence on cognitive impairment in Dialysis patients

Cerebral microbleeds (CMBs) in dialysis patients have recently attracted much attention, and the different locations of CMBs indicate different pathological processes. Previous studies on the relationship between CMBs and cognitive impairment (CI) in the general population and in dialysis patients have reported controversial results. A total of 180 chronic dialysis patients were enrolled in our study. Based on brain magnetic resonance imaging (MRI) analysis of CMBs, the patients were divided into 4 groups (without-CMBs group, strictly lobar group, strictly deep group, and mixed group). A wide range of cognitive tests was administered to evaluate cognitive function. The risk factors for CMBs were explored, and the correlation between CMB distribution and CI was investigated by regression analysis. The prevalence of CMBs was 32.8% in the total study population, 36.1% in the haemodialysis (HD) subgroup and 26.2% in the peritoneal dialysis (PD) PD subgroup. Sixteen subjects (8.9%) were classified as the lobar group, 12 subjects (6.7%) as the mixed group, and 31 subjects (17.2%) as the deep group. A significant association was shown between deep CMBs and impaired cognitive function, involving overall cognitive function, memory, language ability and executive function. Deep CMBs were significantly associated with dialysis vintage, mean arterial pressure (MAP) and lacunar infarcts number, while deep CMBs showed no correlation with dialysis modality and current heparin medication. Deep CMBs are closely associated with global and specific CI in dialysis patients. Blood pressure control may prevent deep CMBs and their associated CI.

Short-term manual compression of hemodialysis fistula leads to a rise in cerebral oxygenation

BACKGROUND

Decreased cerebral perfusion and oxygenation are common in hemodialysis patients. Magnitude of the arteriovenous fistula involvement in this phenomenon is not known. The aim of this study was to investigate the effect that a short-term arteriovenous fistula flow interruption has on cerebral oxygenation and to review and suggest possible explanations.

METHODS

In 19 patients, basic laboratory and clinical data were obtained and arteriovenous fistula flow volume was measured by ultrasonography. Baseline regional cerebral oxygen saturation (rSO₂) was measured by near-infrared spectroscopy. Manual pressure was then applied on the fistula, resulting in total blood flow interruption. After 1 min of manual compression, rSO₂ and blood pressure values were noted again. The compression-related change in rSO₂ was assessed, as well as its association with arteriovenous fistula flow volume, blood pressure, and other parameters.

RESULTS

Mean cerebral rSO₂ increased after arteriovenous fistula compression (from 53.6% ± 11.4% to 55.6% ± 10.8%; p = 0.000001; 95% confidence interval = 1.39-2.56). The rSO₂ increase was higher in patients with lower rSO₂ at baseline (r = -0.46; p = 0.045).

CONCLUSION

A significant rise in cerebral oxygenation was observed following the manual compression of arteriovenous fistula. Therefore, the arteriovenous fistula could have a role in impaired cerebral oxygenation in hemodialysis patients.

Shared decision-making in advanced kidney disease: a scoping review protocol

INTRODUCTION

Patients with advanced kidney disease (AKD) have to make difficult treatment modality decisions as their disease progresses towards end-stage kidney disease. International guidelines in nephrology suggest shared decision-making (SDM) to help patients make timely treatment modality decisions that align with their values and preferences. However, systematic reviews or scoping reviews on these SDM interventions and on their reported use or outcomes are lacking. This limits the adoption of SDM in clinical practice and hampers further research and development on the subject. Our aim is to provide a comprehensive and up-to-date overview of these SDM interventions by means of a scoping review of the literature. Scoping reviews can provide a broad overview of a topic, identify gaps in the research knowledge base and report on the types of evidence that address and inform practices. This paper presents our study protocol.

METHODS AND ANALYSIS

The proposed scoping review will be performed in accordance with the Joanna Briggs Institute's (JBI) methodology for scoping reviews. It will cover both qualitative and quantitative scientific literature, as well as the grey literature on SDM interventions for treatment modality decisions in AKD. Only literature written in English will be considered for inclusion. Two independent reviewers will participate in an iterative process of screening the literature, paper selection and data extraction. Disagreements between the reviewers will be resolved by discussion until consensus is reached or after consultation with the research team when needed. Results will be reported with descriptive statistics and diagrammatic or tabular displayed information, accompanied by narrative summaries as explained in the JBI guidelines.

ETHICS AND DISSEMINATION

Ethical approval for the conduct of this study is not required. We will analyse previously collected data for the proposed scoping review. Our results will be published in a peer-reviewed journal and disseminated through conferences and/or seminars.

Effect of valerian on cognitive disorders and electroencephalography in hemodialysis patients: a randomized, cross over, double-blind clinical trial

BACKGROUND

The prevalence of cognitive disorders in hemodialysis patients is twice as high as the general population, while these disorders often are undiagnosed. Timely prevention and treatment can improve their personal and social functions. Aim of study was determined the effect of Valerian on cognitive disorders and electroencephalography (EGG) in hemodialysis patients.

METHODS

This crossover, double-blind clinical trial was conducted on 39 hemodialysis patients. The patients were randomly divided into two groups. Group A (n = 19) took Valerian capsules and Group B (n = 20) received placebo capsules 60 min before bedtime for one month. The type of treatment was replaced between the two groups after a one-month wash-out. The Mini Mental State Examination (MMSE) questionnaire was completed and EGG was performed before and after intervention in both periods.

RESULTS

The cognitive scores of the Group valerian were increased significantly in the first (p = 0.003) and the second (p = 0.005) periods. In addition, the mean increase in the cognitive scores in the Group valerian was significant in the first (p = 0.028) and the second periods (p = 0.030). However, the changes in EGG showed no significant difference before and after intervention in two groups.

CONCLUSION

The findings of this study indicated that valerian could be effective and significantly improve patients' cognitive status; however, no significant changes were observed in the electroencephalography of the hemodialysis patients.

TRIAL REGISTRATION

IRCT201606076318N7 -2016-06-17.