Cognitive Impairment and Progression of CKD

Diagnosis and Management of Dementia for the Nephrology Clinician: A Review

Dementia describes when a person has cognitive limitations that impede function. Persons with kidney disease are unduly impacted by dementia: up to 87% of the dialysis population has cognitive impairment. In this review, we discuss the diagnosis and management of dementia, including the role of cerebrovascular disease and other risk factors. We review the available screening tools for the diagnosis of dementia. We discuss how the diagnosis of dementia differs from the diagnosis of mild cognitive impairment and also detail how delirium and depression can mimic dementia. In terms of treatments for dementia, we highlight 4 components. First, we describe pharmacologic treatments for the management of dementia, including the cholinesterase inhibitors N-methyl-d-aspartate antagonists as well as the newer antiamyloid antibody drugs for Alzheimer dementia. Second, we discuss the importance of nonpharmacologic interventions for the management of dementia, especially exercise. Third, we review approaches for the behavioral and neuropsychiatric symptoms associated with dementia, including potential medication management. Fourth, we highlight the essential and valuable role of caregivers in both the diagnosis and management of dementia. We conclude with key considerations about the impact of dementia for persons receiving dialysis and the role of dementia in kidney transplant evaluation.

Neuroprotective Effects of Sodium Nitroprusside on CKD-Induced Cognitive Dysfunction in Rats: Role of CBS and Nrf2/HO-1 Pathway

Chronic kidney disease (CKD) is a conceivable new risk factor for cognitive disorder and dementia. Uremic toxicity, oxidative stress, and peripheral-central inflammation have been considered important mediators of CKD-induced nervous disorders. Nitric oxide (NO) is a retrograde neurotransmitter in synapses, and has vital roles in intracellular signaling in neurons. This research aims to determine the effectiveness of NO in CKD-induced cognitive deficits by considering the nuclear factor-erythroid factor 2-related factor 2 (Nrf2)/ heme oxygenase-1 (HO-1) signaling pathway and the important roles of cystathionine beta-synthase (CBS, H2S producing enzyme). Forty rats were divided into four experimental groups: sham, five-sixth (5/6) nephrectomy (5/6Nx, CKD), CKD + NO donor (Sodium nitroprusside, SNP), CKD + SNP and a CBS inhibitor (amino-oxy acetic acid, AOAA). To assess the neurocognitive abilities, eleven weeks after 5/6Nx, behavioral tests (Novel object recognition test, Passive avoidance test, and Barnes maze test) were done. Twelfth week after 5/6Nx, blood urea nitrogen (BUN) and serum creatinine (sCr) levels, as well as the nuclear factor-erythroid factor 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) expression levels and neuronal injury in the hippocampus and prefrontal cortex were assessed. As predicted, the levels of BUN and sCr (both P < 0.001) and neuronal injury in the hippocampus (P < 0.001 for CA1; CA3; DG) and prefrontal cortex (P < 0.001) increased in CKD rats as well as 5/6Nx induced reduction of Nrf2 (both P < 0.001) /HO-1(P < 0.001; P < 0.01 respectively) pathway activity in the hippocampus and prefrontal cortex in CKD rats. Moreover, CKD leads to cognitive disorder and memory loss (Novel object recognition test (NOR) (P < 0.001), Passive avoidance test (PA) (P < 0.001) and Barnes maze (BA) (Escape latency (P < 0.001); Error (P < 0.001)). SNP treatment significantly improved Nrf2 (both P < 0.001) /HO-1 (P < 0.001; P < 0.05 respectively) pathways and neuronal injury (P < 0.001 for CA1; CA3; DG) in the hippocampus and prefrontal cortex in CKD rats as well as enhanced learning and memory ability in CKD rats. However, ameliorating effects of SNP on cognitive disorder (NOR (P < 0.05), PA (P < 0.001) and BA (Escape latency (P < 0.05); Error (P < 0.001)) and Nrf2 (P < 0.01; P < 0.001 in the hippocampus and prefrontal cortex respectively) /HO-1 (P < 0.05 in both) signaling pathway activity were nullified by CBS inhibitor and H2S reduction. In conclusion, this study demonstrated that NO improved CKD-induced cognitive impairment and neuronal death which is may be depended to CBS activity and endogenous H2S levels.

Association of chronic kidney disease with cognitive impairment risk in middle-aged and older adults: the first longitudinal evidence from CHARLS

Previous studies have yielded inconsistent results regarding the association between chronic kidney disease (CKD) and the risk of cognitive impairment (CI). This study aimed to investigate the longitudinal association of CKD with CI risk in the Chinese middle-aged and older population. A total of 16,515 CI-free participants 45 years of age or older including 15,595 without CKD and 920 with CKD were followed from 2011 until 2018 (median [interquartile range]: 7 [5.5-7]) to detect incident CI. Over the follow-up, 648 participants developed CI. Data were analyzed using multi-adjusted Cox proportional hazard regression and Laplace regression. The incidence rate (IR) of CI was significantly higher in individuals with CKD at 11.46 per 1,000 person-years (95% confidence interval [CI], 8.90 to 14.76) than in those without CKD at 6.38 per 1,000 person-years (95% CI, 5.89 to 6.92). Compared to those without CKD, the hazard ratios of those with CKD was 1.56 (95% CI, 1.19 to 2.04) for CI. Participants with CKD in the middle-aged group (45-54 years) exhibited a heightened risk of CI in age-stratified analyses. CKD accelerated the onset of CI by 1.24 years (10th percentile difference [PD]; 95% CI, -2.03 to -0.43, p < 0.01). The findings from this study revealed a significantly increased risk of CI in individuals with CKD, especially in middle-aged population, where the risk appeared to be more pronounced. This observation underscores the importance of early detection and intervention strategies to alleviate the potential cognitive decline associated with CKD.

Kidney-brain axis in the pathogenesis of cognitive impairment

The kidney-brain axis is a bidirectional communication network connecting the kidneys and the brain, potentially affected by inflammation, uremic toxin, vascular injury, neuronal degeneration, and so on, leading to a range of diseases. Numerous studies emphasize the disruptions of the kidney-brain axis may contribute to the high morbidity of neurological disorders, such as cognitive impairment (CI) in the natural course of chronic kidney disease (CKD). Although the pathophysiology of the kidney-brain axis has not been fully elucidated, epidemiological data indicate that patients at all stages of CKD have a higher risk of developing CI compared with the general population. In contrast to other reviews, we mentioned some commonly used medicines in CKD that may play a pivotal role in the pathogenesis of CI. Revealing the pathophysiology interactions between kidney damage and brain function can reduce the potential risk of future CI. This review will deeply explore the characteristics, indicators, and potential pathophysiological mechanisms of CKD-related CI. It will provide a theoretical basis for identifying CI that progresses during CKD and ultimately prevents and treats CKD-related CI.

Association between cerebral blood flow variation and cognitive decline in older patients undergoing hemodialysis

Background

The mechanism of cognitive impairment in hemodialysis patients is multifactorial. The relationship between cerebral blood flow and the decline of cognitive function is poorly understood.

Objective

To investigate the association between cerebral blood flow variation and decline of cognitive function in older patients undergoing hemodialysis.

Methods

In this prospective observational cohort study of 121 older patients undergoing hemodialysis, we used transcranial Doppler ultrasound (TCD) to measure cerebral arterial mean flow velocity (MFV) throughout dialysis, assessed cognitive function at baseline and 12-month follow-up, and then analyzed associations between MFV and changes on cognitive scores.

Results

TCD recordings demonstrated a significant reduction in MFV throughout dialysis, which were significantly correlated with cumulative ultrafiltration volume (rho 0.356, p < 0.001), ΔSBP (rho 0.251, p = 0.005), and ΔMAP (rho 0.194, p = 0.032). Compared with the baseline assessments, cognitive scores of participants at the 12-month follow-up were significantly worsened in global cognition (MOCA), some tests of memory (CFT-memory), executive function (TMT-B, SCWT-C, and SCWT-T), attention/processing speed (SDMT), and visuospatial function (CFT-copy) (p < 0.05). The worsening scores in global cognition (MOCA) (β = 0.066, 95% CI 0.018-0.113, p = 0.007) and some tests of memory (AVLT5) (β = 0.050, 95% CI 0.004-0.097, p = 0.035) and executive function (TMT-B, SCWT-C, SCWT-T) (β = 1.955, 95% CI 0.457-3.453, p = 0.011; β = 0.298, 95% CI 0.112-0.484, p = 0.002 and β = 1.371, 95% CI 0.429-2.303, p = 0.004, respectively) were significantly associated with the reduction of MFV.

Conclusion

Hemodialysis may significantly reduce cerebral blood flow in older patients; Repetitive intradialytic decreases in CBF may be one of the mechanisms underlying the decline of cognitive function.

Clinical trial registration

https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000C5B5&selectaction=Edit&uid=U0003QEL&ts=4&cx=-djoi2.

A life-changing process when living with chronic kidney disease: A qualitative study

BACKGROUND

Patients with chronic kidney disease and their family members experience a number of lifestyle changes caused by the illness. The value of advance care planning includes understanding health status and options for future care, communication between close family members, and identification of wishes and preferences for care and treatment in relation to family and everyday life.

OBJECTIVE

Explore how patients with chronic kidney disease and their families experience everyday life and how they experience having to make choices about treatment.

DESIGN

An explorative study using a qualitative method with a phenomenological-hermeneutic approach.

PARTICIPANTS

Twelve patients with chronic kidney disease without kidney replacement therapy who were considering their treatment options and eight family members.

APPROACH

Individual semistructured interviews with a narrative approach were conducted between August 2021 and March 2022. The data were analysed using Ricoeur's interpretation theory on three levels: naïve reading, structural analysis and critical interpretation and discussion.

FINDINGS

One main theme was generated: Family dynamics in a life-changing process. From this, three subthemes were derived: Living in an ordinary life placed in a waiting position, The dilemma of readiness to share and Feelings of being left alone.

CONCLUSION

There are changes in family roles and in identity and a desire to maintain the known and ordinary life. Living with chronic kidney disease as a part of daily life is managed differently in the family, which can lead to feelings such as sadness, frustration and loss of shared life and resilience.

Association Between Cognitive Function and Risk of Chronic Kidney Disease: A Longitudinal Cohort and Mendelian Randomization Study

OBJECTIVE

To investigate the causal dose-response association between cognitive function and the risk of chronic kidney disease (CKD) by a longitudinal cohort and mendelian randomization study.

METHODS

The longitudinal cohort study included 396,600 participants without prior dementia and CKD from the UK Biobank. Cognitive function (including prospective memory, numeric memory, visuospatial memory, reaction time, and reasoning ability) was assessed by computerized touchscreen tests. Global cognitive function was defined as a composite score of those specific cognitive domains. A 2-stage mendelian randomization analysis was conducted with 12,979 cases of CKD and 379,424 controls. Genetically predicted global cognitive function was instrumented with 91 confirmed genome-wide significant variants. The study outcome was new-onset CKD. The study was conducted from March 13, 2006, to September 30, 2021.

RESULTS

During a median follow-up of 12.5 years, new-onset CKD developed in 13,090 participants. Per 1 SD score increments in reaction time (adjusted hazard ratio [HR], 0.97; 95% CI, 0.95 to 0.99), reasoning ability (adjusted HR, 0.91; 95% CI, 0.88 to 0.94), and global cognitive function (adjusted HR, 0.96; 95% CI, 0.95 to 0.98) were associated with a significantly lower risk of new-onset CKD. Compared with an incorrect answer in the prospective memory test, a correct answer was associated with a lower risk of new-onset CKD (adjusted HR, 0.82; 95% CI, 0.76 to 0.88). Mendelian randomization analyses found that per 1 SD score increments in genetically predicted global cognitive function resulted in a significantly (7%; 95% CI, 2% to 12%) lower risk of new-onset CKD.

CONCLUSION

A better cognitive function is causally associated with a lower risk of CKD in participants without prior dementia.

Acute Effects of Caffeine Ingestion on Postural Balance, Functional Capacity and Cognitive Function in Patients with End Stage Renal Disease

Patients with end stage renal disease (ESRD) display many cognitive and physiological alterations resulting from renal failure and physical inactivity. Caffeine intake has been reported to improve cognitive/physical performance in several studies. However, whether the benefits of caffeine intake apply to patients with ESRD remains unknown. The aim of the present study was to explore the effect of caffeine intake on postural balance, cognitive function and functional capacity in patients with ESRD. In a randomized order, 12 patients with ESRD (age: 33.85 ± 8.57 years; Female: 45.5%) performed a battery of tests after either caffeine (CF) (400 mg) or placebo (PLA) ingestion. Postural balance was evaluated using a stabilometric platform. Functional capacity was assessed with the sit-to-stand and up-and-go tests, and for cognitive performances, reaction time test and a vigilance test were used. Results showed a significant improvement in up-and-go test (p = 0.01) and sit-to-stand test performances with CF compared to PLA (p < 0.01). Time of reaction test and vigilance test (p < 0.01) performances were significantly higher with CF. No significant difference was observed in postural balance between CF and PLA. The results of this study suggest that acute caffeine ingestion positively enhances cognitive function and functional capacity in patients with ESRD.

Prevalence of cognitive impairment and its predictors among chronic kidney disease patients: A systematic review and meta-analysis

BACKGROUND

Cognitive impairment (CI) is common among patients with chronic kidney disease (CKD), and is associated with a poor prognosis. We assessed the prevalence and associated factors of CI in patients with CKD.

METHODS

A systematic review and meta-analysis were conducted by searching PubMed, Embase, and the Web of Science through December 1, 2023. Random effects models were performed with subgroup analyses to further explore the heterogeneity.

RESULTS

50 studies involving 25,289 CKD patients were included. The overall prevalence of CI was 40% (95% confidence interval 33-46). The pooled prevalence of CI was relatively higher in CKD patients from Africa (58%), Asia (44%) and America (37%). Attention and executive dysfunction appeared to be the most common manifestations. The prevalence of CI was higher among patients with hemodialysis (53%) and peritoneal dialysis (39%) than those without dialysis (32%) and post-kidney transplanted (26%). In addition, advanced age, the presence of diabetes and hypertension might increase the risk of CI in CKD patients.

CONCLUSIONS

People with CKD have a high prevalence of CI, especially in patients with hemodialysis. An early and comprehensive screening for CI in CKD patients is needed to improve clinical outcomes.

TRIAL REGISTRATION

Registration number: PROSPERO (CRD42023412864).

A nomogram to predict cognitive function impairment in patients with chronic kidney disease: A national cross-sectional survey

BACKGROUND

Cognitive function impairment (CFI) is common in patients with chronic kidney disease (CKD) and significantly impacts treatment adherence and quality of life. This study aims to create a simplified nomogram for early CFI risk detection.

METHODS

Data were obtained from the National Health and Nutrition Examination Survey cycles spanning from 1999 to 2002 and again from 2011 to 2014. Stepwise logistic regression was used to select variables and construct a CFI risk prediction model. Furthermore, C-statistic and Brier Score (BS) assessed model performance. Additionally, Kaplan-Meier survival curves were utilised to assess risk group-death prognosis relationships.

RESULTS

Of the 545 participants in the CKD model development cohort, a total of 146 (26.8 %) had CFI. The final model included the variables of age, race, education, annual family income, body mass index, estimated glomerular filtration rate, serum albumin and uric acid. The model had a C-statistic of 0.808 (95 % confidence interval (CI): 0.769-0.847) and a BS of 0.149. Furthermore, the 5-fold cross-validation internal C-statistic was 0.764 (interquartile range: 0.763-0.807) and BS was 0.154. Upon external validation, the model's C-statistic decreased to 0.752 (95 % CI: 0.654-0.850) and its BS increased to 0.182. The Kaplan-Meier survival curves demonstrated that intermediate-to-high-risk participants had shorter overall survival time than low-risk participants (log-rank test: p = 0.00042).

CONCLUSIONS

This study established an effective nomogram for predicting CFI in patients with CKD, which can be used for the early detection of CFI and guide the treatment of patients with CKD.

Cognitive Impairment and Brain Atrophy in Patients with Chronic Kidney Disease

In Japan, the aging of the population is rapidly accelerating, with an increase in patients with chronic kidney disease (CKD) and those undergoing dialysis. As a result, the number of individuals with cognitive impairment (CI) is rising, and addressing this issue has become an urgent problem. A notable feature of dementia in CKD patients is the high frequency of vascular dementia, making its prevention through the management of classical risk factors such as hypertension, diabetes mellitus, dyslipidemia, smoking, etc., associated with atherosclerosis and arteriosclerosis. Other effective measures, including the use of renin-angiotensin system inhibitors, addressing anemia, exercise therapy, and lifestyle improvements, have been reported. The incidence and progression of CI may also be influenced by the type of kidney replacement therapy, with reports suggesting that long-duration dialysis, low-temperature hemodialysis, peritoneal dialysis, and kidney transplantation can have a preferable effect on the preservation of cognitive function. In conclusion, patients with CKD are at a higher risk of developing CI, with brain atrophy being a contributing factor. Despite the identification of various preventive measures, the evidence substantiating their efficacy remains limited across all studies. Future expectations lie in large-scale randomized controlled trials.

Comparison of the effects of peritoneal dialysis and hemodialysis on spontaneous brain activity in CKD patients: an rs-fMRI study

OBJECTIVE

To compare the effects of peritoneal dialysis and hemodialysis on spontaneous brain activity in patients with end-stage renal disease.

METHODS

A total of 52 dialysis patients with end-stage renal disease, including 25 patients with chronic kidney disease undergoing hemodialysis (HD-CKD) and 27 patients with chronic kidney disease undergoing peritoneal dialysis (PD-CKD), and 49 healthy controls (normal control) were included. All participants underwent neuropsychological testing (Mini-Mental State Examination and Montreal cognitive assessment) and resting-state functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuations and Regional Homogeneity algorithms were employed to evaluate spontaneous brain activity. Statistical analysis was performed to discern differences between the groups.

RESULTS

When compared with the normal control group, the PD-CKD group exhibited significant alterations in fractional amplitude of low frequency fluctuations in various cerebellum regions and other brain areas, while the HD-CKD group showed decreased fractional amplitude of low frequency fluctuations in the bilateral pericalcarine cortex. The Regional Homogeneity values in the PD-CKD group were notably different than those in the normal control group, particularly in regions such as the bilateral caudate nucleus and the right putamen.

CONCLUSION

Both peritoneal dialysis and hemodialysis modalities impact brain activity, but manifest differently in end-stage renal disease patients. Understanding these differences is crucial for optimizing patient care.

Association between kidney measurements and cognitive performance in patients with ischemic stroke

BACKGROUND

Individuals with chronic kidney disease (CKD) are at a substantially higher risk for stroke, which may predispose individuals to cognitive impairment. However, the association of low estimated glomerular filtration rate (eGFR) and albuminuria with poorer cognitive performance in patients with stroke is not fully understood, and the current evidence for this association is contradictory. Our aim was to retrospectively investigate whether low eGFR and albuminuria, as indicated by the urine albumin-creatinine ratio (UACR), are independently or jointly associated with worse cognitive performance in patients with ischemic stroke.

METHODS

This retrospective study included 608 patients with acute ischemic stroke. Their UACR and eGFR values were obtained from inpatient medical records. Global cognitive function was assessed with the mini-mental state exam (MMSE) and Montreal Cognitive Assessment (MoCA) one month after hospital discharge. The relationship between renal measures and cognitive performance was assessed using univariate and multiple linear regression analyses. Potential confounders included age, gender, BMI, education, diabetes and hypertension history, NIHSS score, smoking and alcohol consumption status, serum total cholesterol, triglyceride, fasting glucose, uric acid, homocysteine, systolic blood pressure, and either eGFR or UACR.

RESULTS

Patients had an average age of 66.6±4.1 years, and 48% were females. Average eGFR and UACR were 88.4±12.9 ml/min/1.73m2 and 83.6±314.2 mg/g, respectively. The number of patients with eGFR ≥90, 60-89, and <60 ml/min/1.73 m2 was 371 (61%), 207 (34%), and 30 (5%), respectively, and the percentage of patients with UACR <30 mg/g, 30-300 mg/g, and >300 mg/g was 56%, 39%, and 5%, respectively. Multivariate adjusted models showed that eGFR was independently associated with MMSE (β = -0.4; 95% CI = -0.5,-0.4; p <0.001) and MoCA (β = -0.6; 95% CI = -0.7,-0.5; p <0.001). However, UACR was not significantly correlated with MMSE or MoCA.

CONCLUSION

In patients with ischemic stroke, reduced eGFR but not albuminuria was associated with lower cognitive performance. These results show that the eGFR decline could be an effective indicator of cognitive impairment after a stroke. Therefore, regular monitoring and early detection of mild renal dysfunction in patients with acute ischemic stroke might be needed.

Advance care planning to patients with chronic kidney disease and their families: An intervention development study

AIM

To develop an advance care planning intervention based on the needs of patients with chronic kidney disease, families and healthcare professionals.

BACKGROUND

Patients with chronic kidney disease and their families request early advance care planning that continues throughout their illness trajectory. Healthcare professionals experience barriers to initiating advance care planning. Involvement of stakeholders in development of health interventions is important, to identify priorities, understand the problem and find solutions.

METHOD

The development was inspired by the Medical Research Council's framework, and codesign was applied. One future workshop and one design workshop were conducted with the consumers. The process was iterative, and data were analysed using the action research spiral. The Guidance for reporting intervention development studies in healthcare (GUIDED) was used.

RESULTS

Five areas were considered significant to an advance care planning intervention; a biopsychosocial approach, early palliative care, a family-focused approach, early and continuous advance care planning and a consumer-centred approach. Based on these, a conversation process with healthcare professionals was designed to give patients and families the opportunity to share values, preferences and wishes for treatment and their family and everyday life.

CONCLUSION

Codesign facilitated a collaborative process that allowed the consumers to have a significant impact on the design of an advance care planning intervention. A conversation process concerning everyday life, illness and treatment was designed for patients and families. The intervention included an advance care planning tool to guide the healthcare professionals.

PRACTICE IMPLICATIONS

The intervention has the intention to improve the communication between healthcare professionals, patients and families. The study provides important knowledge about the significance of giving the patients and their families support in sharing their values, preferences and wishes for treatment and everyday life, thus, to improve care and treatment in their illness trajectory.

IMPACT

What problem did the study address Patients with chronic kidney disease and their families strongly request early initiation of advance care planning that continues throughout the illness trajectory. Healthcare professionals experience barriers to the initiation of the advance care planning and request a more systematic approach. What were the main findings Development of a conversation process about everyday life, illness and treatment for patients diagnosed with chronic kidney disease and families, including an advance care planning tool to guide the healthcare professionals. Where and on whom will the research have an impact The study contributes an advance care planning intervention to patients in the early stages of chronic kidney disease and their families. We believe that the intervention could be included during consultations with healthcare professionals in other stages of chronic kidney disease as well as other chronic disease.

REPORTING METHOD

To strengthen the reporting of the development of the advance care planning intervention, we used the Guidance for reporting intervention development studies in healthcare (GUIDED).

PATIENT OR PUBLIC CONTRIBUTION

The development of the intervention in this study was a collaborative process between patients, families, healthcare professionals and representatives from the Danish Kidney Association, the department's user council and the research team.

Chronic Kidney Disease Induces Cognitive Impairment in the Early Stage

OBJECTIVE

Previous research indicates a link between cognitive impairment and chronic kidney disease (CKD), but the underlying factors are not fully understood. This study aimed to investigate the progression of CKD-induced cognitive impairment and the involvement of cognition-related proteins by developing early- and late-stage CKD models in Sprague-Dawley rats.

METHODS

The Morris water maze test and the step-down passive avoidance task were performed to evaluate the cognitive abilities of the rats at 24 weeks after surgery. Histopathologic examinations were conducted to examine renal and hippocampal damage. Real-time PCR, Western blotting analysis, and immunohistochemical staining were carried out to determine the hippocampal expression of brain-derived neurotrophic factor (BDNF), choline acetyltransferase (ChAT), and synaptophysin (SYP).

RESULTS

Compared with the control rats, the rats with early-stage CKD exhibited mild renal damage, while those with late-stage CKD showed significantly increased serum creatinine levels as well as apparent renal and brain damage. The rats with early-stage CKD also demonstrated significantly impaired learning abilities and memory compared with the control rats, with further deterioration observed in the rats with late-stage CKD. Additionally, we observed a significant downregulation of cognition-related proteins in the hippocampus of rats with early-stage CKD, which was further exacerbated with declining renal function as well as worsening brain and renal damage in rats with late-stage CKD.

CONCLUSION

These results suggest the importance of early screening to identify CKD-induced cognitive dysfunction promptly. In addition, the downregulation of cognition-related proteins may play a role in the progression of cognitive dysfunction.

Advance care planning in chronic kidney disease: A national Danish survey of knowledge and attitudes among clinicians

INTRODUCTION

Patients with chronic kidney disease and their families strongly request advance care planning. They want it to start early-before treatment decisions are made-and to be an ongoing process during their illness trajectory. Previous international studies show that health care professionals find there to be significant barriers that impact the extent of involvement in advance care planning.

AIM

To identify Danish nephrology health care professionals' knowledge and attitudes to advance care planning and the status of current advance care planning practice in Denmark.

METHOD

An anonymous, cross-sectional survey was administrated online. The questionnaire was developed in Australia and translated and culturally adapted into Danish. Health care professionals were recruited via email lists. In descriptive statistics and multiple ordinal regression, the influence of the respondents' attributes on the extent of involvement in advance care planning was explored, along with the involvement of family, and skills, comfort, barriers and facilitators in relation to advance care planning.

RESULTS

The 207 respondents comprised nephrologists (23%), other physicians (8%), nurses (62%) and other HCPs (7%), of whom 27% had participated in advance care planning training. In total, 66% indicated that they lacked access to material about advance care planning for patients with chronic kidney disease and 46% indicated that the conversations were performed ad hoc. A total of 47% reported that advance care planning was performed well at their workplace. Reported barriers were time, lack of experience and procedure. Training in advance care planning could facilitate the involvement. Nurses were less likely to feel skilled and comfortable in engaging advance care planning, while those with more than 10 years of experience were more likely to feel skilled and comfortable.

CONCLUSION

Training in advance care planning with patients with chronic kidney disease and their families on both a theoretical and clinical level is important to ensure comfort among health care professionals and to facilitate the extent of involvement. A systematic chronic kidney disease-specific approach is significant, in order to guide the conversations and ensure that advance care planning is conducted to a set standard.

Secondary Hyperparathyroidism and Cognitive Decline

Purpose of Review

Secondary hyperparathyroidism (SHPT) likely contributes to the high prevalence of cognitive decline found among individuals with end-stage kidney disease (ESKD). Our objective is to critically evaluate the recent literature regarding the association between SHPT and cognitive decline and identify potential mechanisms.

Recent Findings

Nine studies assessing the relationship between SHPT and cognition have been published in the last two decades, each showing that elevated parathyroid hormone (PTH) levels were associated with cognitive decline. One also found structural changes within the brain related to SHPT. Additionally, two found that SHPT treatment decreases the risk of cognitive decline in ESKD patients.

Summary

SHPT is associated with cognitive impairment. However, the severity of SHPT associated with these changes and the specific cognitive domains affected remain unclear. Future studies are needed to focus on specific cognitive domains, the trajectory of cognitive decline, and optimal treatment strategies including the impact of kidney transplant and tertiary hyperparathyroidism.

Relationship between homocysteine and cognitive impairment in elderly patients with chronic kidney disease

<b>Aim:</b> To investigate the association of serum homocysteine levels with cognitive function in elderly patients with chronic kidney disease (CKD).<br /> <b>Methods:</b> A case-control study on 200 elderlies &gt;60 years who were distributed into two groups: group 1 (cases): 100 patients with CKD and group 2 (controls): 100 subjects who do not have CKD. All subjects undergo comprehensive geriatric assessment, cognitive assessment, and biochemical investigations including serum homocysteine.<br /> <b>Results:</b> The odds ratio of having impaired clinical dementia rating scores is 3.1 for CKD cases compared to controls. CKD patients have almost 3 times the risk of having cognitive impairment [OR=3.1; 95% CI (1.6-6.0)]. The mean serum homocysteine (18.2 μmol/L) among CKD showed a highly statistically significance compared to controls (10.1 μmol/L). Performance of multiple cognitive domains was reduced in association with elevated homocysteine levels. By using linear regression model for the factors independently related to cognitive performance among studied CKD cases, it was found that diabetes mellitus, educational level, age, and serum homocysteine level were strongly associated with consortium to establish a registry for Alzheimer’s disease neuropsychological battery total scores. Respecting the percentage variance explained by each significant variable (R²), serum homocysteine level is an independent significant variable predictor with the total scores.<br /> <b>Conclusion:</b> The main features of cognitive impairment in CKD patients are executive dysfunction and memory impairment. Poor cognitive function in CKD patients was related with a higher homocysteine level independently.

Association of kidney function and brain health: A systematic review and meta-analysis of cohort studies

OBJECTIVE

This study aimed to evaluate the bidirectional association between the kidney dysfunction and the brain health, including structural and functional abnormalities.

DESIGN

Systematic review and meta-analysis with network meta-analysis for outcomes with different estimated glomerular filtration rate (eGFR) ranges.

DATA SOURCES

PubMed, Embase database, Cochrane library and Web of Science (up to Dec. 2021).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Longitudinal studies that provided evidence of the impact of kidney function estimated from eGFR and urine albumin-to-creatinine ratio (UACR) or chronic kidney disease (CKD) on structural and functional brain abnormalities, and those that provided evidence of the opposite relationship. Studies with study population mean age under 18 years old were excluded.

MAIN OUTCOME MEASURES

Two independent reviewers screened the included studies, extracted the data, and assessed the risk of bias. We performed a random-effects meta-analysis and a network meta-analysis for outcomes with compatible data. We assessed the risk of bias using the Newcastle-Ottawa Quality Assessment Scale criteria (NOS). Subgroup and sensitivity analyses were conducted to explore heterogeneity in the meta-analyses. Inconsistency analyses using the node-splitting method were performed to confirm the results of network meta-analysis.

RESULTS

A total of 53 studies with 3037,357 participants were included in the current systematic review. Among these, 16 provided evidence of structural brain abnormalities, and 38 provided evidence of cognitive impairment and dementia. Analysis of evidence of categorical kidney function showed a positive association between kidney dysfunction and cerebral small vessel disease (cSVD) (relative risk (RR) 1.77, 95% confidence interval (CI) 1.40-2.24, I² = 0.0%), but such results were not found in the analyses of evidence where the kidney function was measured as a continuous variable. Meanwhile, analysis of 28 prior longitudinal studies with 194 compatible sets of data showed that the worse kidney function as categorical variables was related to a greater risk of global brain cognitive disorder (RR 1.28, 95% CI 1.20-1.36, I² = 82.5%).

CONCLUSIONS

In this systematic review and meta-analysis, we found a positive association between CKD and functional brain disorders. However, the relationship between the kidney dysfunction and structural abnormalities in the brain remains controversial. As for the opposite relationship, structural brain abnormalities, especially cerebral microbleeds and silent infarction, but not functional brain abnormalities, are associated with worse renal function. In addition, a higher UACR, but not a lower eGFR, was associated with a higher risk of Alzheimer's disease and vascular dementia.

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.

Association of Proximal Tubular Secretory Clearance with Long-Term Decline in Cognitive Function

BACKGROUND

People with chronic kidney disease (CKD) are at high risk for cognitive impairment and progressive cognitive decline. Retention of protein-bound organic solutes that are normally removed by tubular secretion is hypothesized to contribute to cognitive impairment in CKD.

METHODS

We followed 2362 participants who were initially free of cognitive impairment and stroke in the prospective Chronic Renal Insufficiency Cohort (CRIC) Study. We estimated tubular secretory clearance by the 24-hour kidney clearances of eight endogenous solutes that are primarily eliminated by tubular secretion. CRIC study investigators assessed participants' cognitive function annually using the Modified Mini-Mental State (3MS) Examination. Cognitive decline was defined as a sustained decrease of more than five points in the 3MS score from baseline. Using Cox regression models adjusted for potential confounders, we analyzed associations between secretory solute clearances, serum solute concentrations, and cognitive decline.

RESULTS

The median number of follow-up 3MS examinations was six per participant. There were 247 incident cognitive decline events over a median of 9.1 years of follow-up. Lower kidney clearances of five of the eight secretory solutes (cinnamoylglycine, isovalerylglycine, kynurenic acid, pyridoxic acid, and tiglylglycine) were associated with cognitive decline after adjustment for baseline eGFR, proteinuria, and other confounding variables. Effect sizes ranged from a 17% to a 34% higher risk of cognitive decline per 50% lower clearance. In contrast, serum concentrations of the solutes were not associated with cognitive decline.

CONCLUSIONS

Lower kidney clearances of secreted solutes are associated with incident global cognitive decline in a prospective study of CKD, independent of eGFR. Further work is needed to determine the domains of cognition most affected by decreased secretory clearance and the mechanisms of these associations.

Cerebral oxygenation and body mass index association with cognitive function in chronic kidney disease patients without dialysis: a longitudinal study

In chronic kidney disease (CKD) patients, the prevalence of cognitive impairment increases with CKD progression; however, longitudinal changes in cognitive performance remain controversial. Few reports have examined the association of cerebral oxygenation with cognitive function in longitudinal studies. In this study, 68 CKD patients were included. Cerebral regional oxygen saturation (rSO₂) was monitored. Cognitive function was evaluated using mini-mental state examination (MMSE) score. Clinical assessments were performed at study initiation and 1 year later. MMSE score was higher at second measurement than at study initiation (p = 0.022). Multivariable linear regression analysis showed that changes in MMSE were independently associated with changes in body mass index (BMI, standardized coefficient: 0.260) and cerebral rSO₂ (standardized coefficient: 0.345). This was based on clinical factors with p < 0.05 (changes in BMI, cerebral rSO₂, and serum albumin level) and the following confounding factors: changes in estimated glomerular filtration rate, hemoglobin level, proteinuria, salt and energy intake, age, presence of diabetes mellitus, history of comorbid cerebrovascular disease, and use of renin–angiotensin system blocker. Further studies with a larger sample size and longer observational period are needed to clarify whether maintaining BMI and cerebral oxygenation improve or prevent the deterioration of cognitive function.

Risk and incidence of cognitive impairment in patients with chronic kidney disease and diabetes: the results from a longitudinal study in a community cohort of patients and an age and gender-matched control cohort in North Wales, UK

OBJECTIVES

The aim of the current investigation is to estimate the incidence and risk for neurocognitive disorders (NCD) in a chronic kidney disease (CKD) cohort with diabetes, compared with an age and sex-matched control cohort.

DESIGN

Longitudinal follow-up.

SETTING

District general hospital North Wales, UK.

PARTICIPANTS

Ninety-two patients with CKD and an age and gender-matched sample of 143 controls at baseline and at approximately 36 months.

INTERVENTIONS

Cognitive function was assessed in the patients with CKD (mean age 75.8±9.1; 49 men: 43 women) and the control cohort (mean age 74.4±6.2; 71 men: 72) at baseline and at approximately 36 months. An NCD diagnosis was based on patient, informant, case note review, neuropsychological assessment and application of Diagnostic and Statistical Manual of Mental disorders V.5 (DSM-5) for an NCD and Petersen's criteria for mild cognitive impairment.

RESULTS

Follow-up neuropsychological assessment and application of DSM-5 criteria of the cognitively normal patients and controls revealed, 25/92 (27%) of the CDK and 20/143 (13.9%) in the control cohort developed an NCD. The CKD cohort had a twofold increased risk for the development of an NCD compared with the controls, adjusted for age and sex. The incidence rate for an NCD in the CKD cohort was 10.5 and 5.1 in the controls, respectively. No association was observed with the stage of CKD and cognitive function.

CONCLUSIONS

This longitudinal investigation found that patients with CKD have a twofold increased risk for the development of an NCD. The current investigation highlighted the need to recognise that NCD in patients with CKD is a common comorbidity and that they are at a much higher risk for the development of a significant neurodegenerative disorders. In view of these risks, neuropsychological screening and assessment should be incorporated into normal CKD clinical practice and management.

A Pilot Observational Study Assessing Long-Term Changes in Clinical Parameters, Functional Capacity and Fall Risk of Patients With Chronic Renal Disease Scheduled for Hemodialysis

Background

Patients with end-stage renal disease are known to be particularly frail, and the cause is still widely seen as being directly related to specific factors in renal replacement therapy. However, a closer examination of the transitional phase from predialysis to long-term hemodialysis leads to controversial explanations, considering that the frailty process is already well-described in the early stages of renal insufficiency. This study aims to describe longitudinally and multifactorially changes in the period extending from the decision to start the replacement therapy through to the end of 2 years of hemodialysis. We hypothesized that frailty is pre-existent in the predialysis phase and does not worsen with the beginning of the replacement therapy. Between 2015 and 2018 we recruited 25 patients (72.3 ± 5.7 years old) in a predialysis program, with the expectation that replacement therapy would begin within the coming few months.

Methods

The patients underwent a baseline visit before starting hemodialysis, with 4 follow-up visits in the first 2 years of treatment. Health status, physical performance, cognitive functioning, hematology parameters, and adverse events were monitored during the study period.

Results

At baseline, our sample had a high variability with patients ranging from extremely frail to very fit. In the 14 participants that did not drop out of the study, out of 32 clinical and functional measures, a statistically significant worsening was only observed in the Short Physical Performance Battery (SPPB) score (p &lt; 0.01, F = 8.50) and the number of comorbidities (p = 0.01, F = 3.94). A careful analysis, however, reveals a quite stable situation in the first year of replacement therapy, for both frail and fit participants and a deterioration in the second year that in frail participants could lead to death.

Conclusion

Our results should stimulate a reassessment about the role of a predialysis program in reducing complications during the transitional phase, but also about frailty prevention programs once hemodialysis has begun, for both frail and fit patients, to maintain satisfactory health status.

Cognitive Domain Impairment and All-Cause Mortality in Older Patients Undergoing Hemodialysis

The highly prevalent cognitive impairment in hemodialysis patients is associated with all-cause mortality; however, the role of different cognitive domain impairments in this association is still not clarified. Our objective was to determine the association between cognitive domain impairment and all-cause mortality in elderly adult patients undergoing hemodialysis. We conducted a prospective cohort study including patients from 11 hemodialysis centers in Beijing. Baseline data were collected, and a series of neuropsychological batteries covering 5 domains of cognitive function were included for the assessment of cognitive function. According to the fifth version of the Diagnostic and Statistical Manual of Mental Disorders criteria (DSM-V), the patients were classified as normal, mild, and major cognitive impairment for global and domain cognitive function, then followed up for 1 year. Kaplan-Meier survival analysis was used to compare the difference in the cumulative survival rate in different cognitive domains. A multivariate Cox proportional hazards regression analysis was used to determine the association between global or domain cognitive impairment and all-cause mortality. A total of 613 patients were enrolled, the mean age was 63.82 ± 7.14 years old, and 42.1% were women. After 49.53 ± 8.42 weeks of follow-up, 69 deaths occurred. Kaplan-Meier plots demonstrated a significant association of cognitive impairment in memory, executive function, attention, and language domains with all-cause death. Multivariate Cox regression analysis showed that mild and major impairment of global cognition (HR = 2.89 (95% CI, 1.01-8.34), p = 0.049 and HR = 4.35 (95% CI, 1.55-12.16), p = 0.005, respectively), executive cognitive domain (HR = 2.51 (95% CI, 1.20-5.24), p = 0.014; HR = 3.91 (95% CI, 1.70-9.03), p = 0.001, respectively), and memory cognitive domain (HR = 2.13 (95% CI, 1.07-4.24), p = 0.031; HR = 3.67 (95% CI, 1.71-7.92), p = 0.001, respectively) were associated with all-cause mortality. Combined impairment of 3, 4, and 5 cognitive domains was associated with all-cause mortality [HR = 5.75 (95% CI, 1.88-17.57), p = 0.002; HR = 12.42 (95% CI, 3.69-41.80), p < 0.001; HR = 13.48 (95% CI, 3.38-53.73), p < 0.001, respectively]. We demonstrate an association between the executive and memory cognitive domain impairment and all-cause mortality in hemodialysis patients. Our data suggest that the impairments in these cognitive domains might help in the early identification of hemodialysis patients at risk of death.

The Influence of Sedentary Behavior on the Relationship Between Cognitive Function and Vascular Function in Older Adults with and without Chronic Kidney Disease

Cognitive impairment and vascular dysfunction are common in older adults with and without chronic kidney disease (CKD). Older adults with and without CKD are also sedentary - a behavior associated with cognitive and vascular function. The objective of this study was to explore whether sedentary behavior influenced the relationship between cognitive and vascular function in older adults with preclinical cognitive impairment with and without CKD. In our study, 48 older adults underwent assessment of cognition, vascular compliance, and sedentary behavior, and relationships were explored with regression moderation analysis. Sedentary time and breaks did not moderate the relationship between vascular and cognitive function. Although significant moderation was not found, cognition, vascular function, and sedentary behavior are important to assess when evaluating older adults with and without CKD.

Patients' with chronic kidney disease and their relatives' perspectives on advance care planning: A meta-ethnography

INTRODUCTION

Advance care planning is a process that supports adults of any age and stage of illness in understanding and sharing their values, life goals, and preferences regarding medical care. Chronic kidney disease is a progressive and lifelong disease. Close relatives often represent patients' most important support. Advance care planning is recommended to be a continuous part of a person's ongoing treatment and is not solely related to end-of-life care. However, no studies have focused on advanced care planning for patients with chronic kidney disease earlier than the onset of a terminal illness.

AIM

The aim is to describe experiences of and perspectives on advance care planning among patients with chronic kidney disease and their close relatives.

METHODS

We conducted a meta-ethnography of studies that used individual, dyad, and focus group interviews. We searched five electronic databases: PubMed, Cinahl, Embase, PsycINFO, and Scopus and reference lists of relevant articles.

RESULTS

Seven articles were included. Participants had a need for advance care planning to make shared decisions about treatment and everyday life. The responsibility for initiating advance care planning lay with the healthcare professionals. Differences between advance care planning goals among patients, relatives, and healthcare professionals complicated the advance care planning process. A focus on day-to-day care at the expense of focusing on advance care planning gave an impression of a lack of competencies and interest. For some patients, the involvement of relatives was of significant value; however, it could be associated with burden and pressure.

CONCLUSION

Patients with chronic kidney disease and their families have a need for early advance care planning before dialysis or transplantation is initiated, so as to facilitate shared decision-making related to treatment options and everyday life. It is important that patients, their relatives, and healthcare professionals share the same advance care planning goals, to get sufficient discussions and thus, achieve clarity about prognosis, medical care, and the illness trajectory.

Sedentary Behavior in Older Adults With Preclinical Cognitive Impairment With and Without Chronic Kidney Disease

Older adults with preclinical cognitive impairment can have chronic conditions and lifestyle factors that influence health. Sedentary behavior is common in older adults with and without chronic kidney disease (CKD). The objective of the current study was to determine the differences in sedentary behavior for older adults with preclinical cognitive impairment with and without CKD. Our study evaluated 48 older adults with preclinical cognitive impairment with and without CKD who underwent assessment of sedentary behavior via accelerometry. We found that older adults with preclinical cognitive impairment with and without CKD were sedentary, but there were no significant differences between groups. Fragmentation index was different (p < 0.05), with a lower fragmentation index found in those with CKD. Sedentary behavior should be assessed and evaluated as a potential target for interventions to improve health in these at-risk older adults; however, further investigation is needed. [Journal of Gerontological Nursing, 47(6), 35-42.].

Risk Factors for CKD Progression: Overview of Findings from the CRIC Study

The Chronic Renal Insufficiency Cohort (CRIC) Study is an ongoing, multicenter, longitudinal study of nearly 5500 adults with CKD in the United States. Over the past 10 years, the CRIC Study has made significant contributions to the understanding of factors associated with CKD progression. This review summarizes findings from longitudinal studies evaluating risk factors associated with CKD progression in the CRIC Study, grouped into the following six thematic categories: (1) sociodemographic and economic (sex, race/ethnicity, and nephrology care); (2) behavioral (healthy lifestyle, diet, and sleep); (3) genetic (apoL1, genome-wide association study, and renin-angiotensin-aldosterone system pathway genes); (4) cardiovascular (atrial fibrillation, hypertension, and vascular stiffness); (5) metabolic (fibroblast growth factor 23 and urinary oxalate); and (6) novel factors (AKI and biomarkers of kidney injury). Additionally, we highlight areas where future research is needed, and opportunities for interdisciplinary collaboration.

Associations of Performance-Based Functional Assessments and Adverse Outcomes in CKD

Background

The comparative utility of performance-based functional assessments in predicting adverse outcomes in CKD is unknown. To examine their relative utility, we examined three performance-based functional assessments in an observational cohort of patients with CKD.

Methods

We recruited 350 participants with stage II-V, predialysis CKD. Participants were administered three performance-based functional assessments: Short Physical Performance Battery (SPPB), Modified Mini-Mental Status Exam (M3SE), and Lawton Instrumental Activities of Daily Living (IADL). Scores were dichotomized on the basis of the median and combined into a summary score. Outcomes included 50% GFR reduction, ESKD, and death. We used Cox proportional hazards to assess the association of performance-based functional assessments with outcomes.

Results

Compared with high performers, low SPPB performers had the highest adjusted rate of death, ESKD, or 50% reduction in GFR (HR, 1.96; 95% CI, 1.28 to 2.99). Low SPPB had the strongest association with death when adjusted for multiple covariates (HR, 2.43; 95% CI, 1.36 to 4.34). M3SE performance was not associated with any adverse outcome. None of the performance-based functional assessments were associated with ESKD, but a low IADL score was associated with a lower hazard ratio for ESKD or 50% decline GFR (HR, 0.49; 95% CI, 0.24 to 1.00).

Conclusions

Low SPPB score was the strongest predictor of death and all adverse outcomes as a composite. Future trials should determine if outcomes for patients with CKD who have poor physical performance and low SPPB scores are improved by targeted interventions.

Clinical Trial registry name and registration number

Safe Kidney Care Cohort Study, NCT01407367.

Opioid Use in the Nondialysis Chronic Kidney Disease Population

Although pain is a common and burdensome condition in patients with chronic kidney disease (CKD), little is known about the use and safety of opioids in this patient population. Recommendations regarding opioid use in patients with CKD are based on pharmacokinetic data, extrapolation from non-CKD studies, and from clinical experience. Given the potential increased risk for opioid-related adverse events in patients with reduced kidney function, health care providers may be hesitant to prescribe opioids, resulting in inadequate pain control. This review summarizes current studies of opioid use in patients with CKD, highlights special considerations, and proposes an opioid prescribing strategy for this unique patient population. Specifically, oral hydromorphone, transdermal fentanyl, and buprenorphine should be considered as the first-line opioids for patients with CKD if opioid management is indicated. A stepwise approach such as the Screen-Quantify-Use opioids-Adjust-Reassess-Engage prescribing strategy proposed here is critical to ensure optimal pain control while minimizing the side effects and adverse events of opioids. The effects of opioids on clinically relevant outcomes in the CKD population remains to be explored in future studies.

Design and methodology of the Aging Nephropathy Study (AGNES): a prospective cohort study of elderly patients with chronic kidney disease

BACKGROUND

Renal replacement therapy (RRT) is usually indicated for patients with chronic kidney disease (CKD) with glomerular filtration rate below 10 ml/ml/min/1.73m². However, the need for RRT and timing of dialysis initiation are debatable for patients aged 70 years or older. We here describe the study design and methodology of the Aging Nephropathy Study (AGNES) protocol that aims at evaluating to what extent geriatric-related conditions such as frailty, cognitive dysfunction, and presence of comorbidities have an impact on survival and RRT initiation in this group of patients. In this manuscript we provide detailed information about the AGNES study design and methodology.

METHODS

AGNES is a prospective observational cohort that aim to investigate clinical, biochemical and demographic factors associated with RRT initiation and mortality of patients with CKD stage 4 or 5 who are aged 70 years and older. We plan to include 200 patients over 5 years. Clinically stable outpatients on conservative management for at least 6 months will be recruited from the Nephrogeriatric Clinic at the Hospital das Clinicas da Universidade de Sao Paulo, Brazil. Eligible patients are submitted to a full clinical examination, geriatric assessment, and blood test at baseline. Following the baseline visit the patients are being monitored during an observational follow up period of at least 12 months during which patients will be contacted in the clinic at their regular follow up or by phone until either RRT initiation or death occurs. This cohort includes evaluation of cognition by the education-adjusted 10-point Cognitive Screener (10-CS), frailty by Fried index score, a complete nutritional assessment (by body composition assessment, global subjective assessment and dietary intake), comorbidities by Charlson comorbidity index and biochemical markers including FGF-23 and Klotho.

DISCUSSION

The AGNES cohort, a real-world study of current clinical practice in elderly patients with advanced CKD prior to dialysis initiation, will shed light into progression of CKD and its complications, indications of RRT and factors determining survival. This investigation will elucidate to what extent geriatric conditions, nutritional status and clinical factors are associated with survival, quality of life and RRT initiation in elderly CKD patients not yet on dialysis.

TRIAL REGISTRATION

Registered on ClinicalTrials.gov on 18 October 2019 ( NCT04132492 ).

Comparison of microwave ablation treatments in patients with renal secondary and primary hyperparathyroidism

Purpose

Microwave ablation (MWA) is feasible for severe renal secondary hyperparathyroidism (SHPT) and primary hyperparathyroidism (PHPT) patients ineligible for parathyroidectomy (PTX). Here we compared the clinical manifestations and characteristics of parathyroid glands in these two groups, and summarized the techniques, safety and efficacy of MWA.

Methods

Baseline clinical characteristics, ablation-related techniques, adverse events/complications, and efficacy were recorded.

Results

In SHPT group, malnutrition, cardiovascular/pulmonary complications, and abnormal bone metabolism were severe. SHPT patients had more hyperplastic parathyroid glands. The volume of each gland was smaller, and the time of ablation for a single parathyroid was shorter in the SHPT group, although there were no significant differences compared with patients in the PHPT group. Three patients in both groups had recurrent laryngeal nerve injuries and all recovered, except for one SHPT patient. By the end of follow-up, serum iPTH levels had decreased from 2400.26 ± 844.26 pg/mL to 429.39 ± 407.93 pg/mL (p < .01) in SHPT and from 297.73 ± 295.32 pg/mL to 72.22 ± 36.51 pg/mL in PHPT group (p < .01). Hypocalcemia was more common (p < .001) and serum iPTH levels were prone to rebound in SHPT patients after MWA.

Conclusion

MWA can be reserved for those who had high surgical risks because of less invasiveness. Injuries of recurrent laryngeal nerves should be noticed. The health status, perioperative, and intraoperative procedures were more complicated and all parathyroids found by ultrasound should be ablated completely in SHPT patients.

White Matter Microstructure Changes and Cognitive Impairment in the Progression of Chronic Kidney Disease

Background

Cognitive impairment is a well-defined complication of chronic kidney disease (CKD), but the neural mechanisms are largely unknown.

Objectives

The study aimed to assess white matter (WM) microstructure changes and their relationship with cognitive impairment development during CKD progression.

Methods

Diffusion tensor imaging (DTI) datasets were acquired from 38 patients with CKD (19 patients were at stage 3; 19 patients were at stage 4) and 22 healthy controls (HCs). Tract-based spatial statistics (TBSS) was implemented to assess the differences in WM integrity among the three groups. The associations between abnormal WM integrity and clinical indicators (digit symbol test scores, the type A number connection test scores, hemoglobin, serum urea, serum creatinine, serum calcium, and serum potassium levels) were also computed.

Results

Compared with patients with CKD at stage 3 and HCs, patients with CKD at stage 4 showed significantly lower fractional anisotropy (FA) and higher mean diffusivity (MD) in the corpus callosum (CC), anterior thalamic radiation, inferior fronto-occipital fasciculus, and inferior longitudinal fasciculus. Correlation analysis showed that the MD in the genu of CC was negatively associated with the digit symbol test scores (r = -0.61, p = 0.01), and the FA in the left anterior thalamic radiation was positively associated with the level of serum calcium (r = 0.58, p = 0.01).

Conclusion

Patients with non-end-stage CKD have multiple abnormalities in WM regions. DTI metrics change with the progression of CKD and are primarily associated with cognitive impairment. The reduced integrity of WM tracts may be related to a low level of blood calcium.

Abnormalities in gut microbiota and serum metabolites in hemodialysis patients with mild cognitive decline: a single-center observational study

RATIONALE

Although a growing body of evidence indicates that the scores of cognitive function in hemodialysis patients are significantly lower than those of healthy individuals, underlying mechanisms have not been fully elucidated.

OBJECTIVES

To investigate the roles of gut microbiota and serum metabolites in hemodialysis patients with mild cognitive decline (MCD).

METHODS

A total of 30 healthy individuals and 77 hemodialysis patients were enrolled and were classified into healthy control (HC), normal cognitive function (NCF), and MCD groups by evaluation of Montreal Cognitive Assessment. Fecal samples were analyzed by 16S rRNA and serum samples were analyzed by gas chromatography-mass spectrometry from all subjects.

RESULTS

The 16S rRNA study demonstrated that the gut microbiota profiles, including α- and β-diversity, and a number of 16 gut bacteria were significantly altered in the MCD group compared with those in HC or those with NCF. A metabonomics study showed that a total of 29 serum metabolites were altered in the MCD group. Receiver operating characteristic curves showed that Genus Bilophila and serum putrescine might be sensitive biomarkers to indicate MCD in patients with hemodialysis.

CONCLUSIONS

These findings demonstrate gut microbiota and serum metabolites were probably involved in the pathogenesis of hemodialysis-related MCD. Therapeutic strategies targeting abnormalities in gut microbiota and serum metabolites may facilitate the beneficial effects for hemodialysis patients with MCD.

Cognitive Impairment, Chronic Kidney Disease, and 1-Year Mortality in Older Patients Discharged from Acute Care Hospital

The prognostic interaction between chronic kidney disease (CKD) and cognitive impairment is still to be elucidated. We investigated the potential interaction of overall cognitive impairment or defective constructional praxis and CKD in predicting 1-year mortality among 646 older patients discharged from hospital. The estimated glomerular filtration rate (eGFR) was calculated using the Berlin Initiative Study (BIS) equation. Cognitive impairment was assessed by the Mini Mental State Exam (MMSE) and defective constructional praxis was ascertained by the inherent MMSE item. The study outcome was 1-year mortality. Statistical analysis was carried out using Cox regression. After adjusting for potential confounders, the co-occurrence of eGFR <30 and overall cognitive impairment (Hazard Ratio (HR) = 3.12, 95% Confidence Interval (CI) = 1.26-7.77) and defective constructional praxis (HR = 2.50, 95% CI = 1.08-5.77) were associated with the outcome. No significant prognostic interaction of eGFR < 30 with either overall cognitive impairment (HR = 1.99, 95% CI = 0.38-10.3) or constructional apraxia (HR = 1.68, 95% CI = 0.33-8.50) was detectable, while only cognitive deficits were found significantly associated with the outcome in the interaction models (HR = 3.12, 95% CI = 1.45-6.71 for overall cognitive impairment and HR = 2.16, 95% CI = 1.05-4.45 for constructional apraxia). Overall cognitive impairment and defective constructional praxis may be associated with increased risk of 1-year mortality among older hospitalized patients with severe CKD. However, no significant prognostic interaction between CKD and cognitive impairment could be observed.

When kidney transplantation is not an option: Haemodialysis patients' and partners' experiences-A qualitative study

Aim

To investigate the experiences and perspectives of everyday life among patients on lifelong haemodialysis and their partners.

Design

A qualitative exploratory study with a phenomenological-hermeneutic approach.

Method

Data were collected through individual interviews. In total, five patients in haemodialysis and their partners were included in the study. Data were analysed with inspiration from Ricoeur's theory around narratives and interpretation on three levels: naïve reading, structural analysis and critical interpretation and discussion. Data was collected between February 2018-June 2019.

Results

Limitations caused by the disease and time-consuming treatment influenced daily life. In particular, the partners needed to have time on their own. Knowledge about the disease and participation in treatment were significant to both patients and partners. There were considerations about illness progression. Relationships to their social networks and healthcare professionals were a significant and important part of daily life for both parties.

Association of 24-Hour Ambulatory Blood Pressure Patterns with Cognitive Function and Physical Functioning in CKD

BACKGROUND AND OBJECTIVES

Hypertension is highly prevalent in patients with CKD as is cognitive impairment and frailty, but the link between them is understudied. Our objective was to determine the association between ambulatory BP patterns, cognitive function, physical function, and frailty among patients with nondialysis-dependent CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Ambulatory BP readings were obtained on 1502 participants of the Chronic Renal Insufficiency Cohort. We evaluated the following exposures: (1) BP patterns (white coat, masked, sustained versus controlled hypertension) and (2) dipping patterns (reverse, extreme, nondippers versus normal dippers). Outcomes included the following: (1) cognitive impairment scores from the Modified Mini Mental Status Examination of <85, <80, and <75 for participants <65, 65-79, and ≥80 years, respectively; (2) physical function, measured by the short physical performance battery (SPPB), with higher scores (0-12) indicating better functioning; and (3) frailty, measured by meeting three or more of the following criteria: slow gait speed, muscle weakness, low physical activity, exhaustion, and unintentional weight loss. Cognitive function and frailty were assessed at the time of ambulatory BP (baseline) and annually thereafter. SPPB was assessed at baseline logistic and linear regression and Cox discrete models assessed the cross-sectional and longitudinal relationship between dipping and BP patterns and outcomes.

RESULTS

Mean age of participants was 63±10 years, 56% were male, and 39% were black. At baseline, 129 participants had cognitive impairment, and 275 were frail. Median SPPB score was 9 (interquartile range, 7-10). At baseline, participants with masked hypertension had 0.41 (95% CI, -0.78 to -0.05) lower SPPB scores compared with those with controlled hypertension in the fully adjusted model. Over 4 years of follow-up, 529 participants had incident frailty, and 207 had incident cognitive impairment. After multivariable adjustment, there was no association between BP or dipping patterns and incident frailty or cognitive impairment.

CONCLUSIONS

In patients with CKD, dipping and BP patterns are not associated with incident or prevalent cognitive impairment or prevalent frailty.

Gut microbiota and chronic kidney disease: evidences and mechanisms that mediate a new communication in the gastrointestinal-renal axis

Chronic kidney disease (CKD) represents a growing public health problem associated with loss of kidney function and cardiovascular disease (CVD), the main leading cause of morbidity and mortality in CKD. It is well established that CKD is associated with gut dysbiosis. Over the past few years, there has been a growing interest in studying the composition of the gut microbiota in patients with CKD as well as the mechanisms by which gut dysbiosis contributes to CKD progression, in order to identify possible therapeutic targets to improve the morbidity and survival in CKD. The purpose of this review is to explore the clinical evidence and the mechanisms involved in the gut-kidney crosstalk as well as the possible interventions to restore a normal balance of the gut microbiota in CKD. It is well known that the influence of the gut microbiota on the gut-kidney axis acts in a reciprocal way: on the one hand, CKD significantly modifies the composition and functions of the gut microbiota. On the other hand, gut microbiota is able to manipulate the processes leading to CKD onset and progression through inflammatory, endocrine, and neurologic pathways. Understanding the complex interaction between these two organs (gut microbiota and kidney) may provide novel nephroprotective interventions to prevent the progression of CKD by targeting the gut microbiota. The review is divided into three main sections: evidences from clinical studies about the existence of a gut microbiota dysbiosis in CKD; the complex mechanisms that explain the bidirectional relationship between CKD and gut dysbiosis; and reports regarding the effects of prebiotic, probiotic, and synbiotic supplementation to restore gut microbiota balance in CKD.

Alterations in Structural and Functional Connectivities in Patients with End-Stage Renal Disease

Background and Purpose

The aim of this study was to evaluate the structural and functional connectivities of brain network using graph theoretical analysis in neurologically asymptomatic patients with end-stage renal disease (ESRD). We further investigated the prevalence of cognitive impairment (CI) in ESRD patients and analyzed the association between network measures of brain connectivity and cognitive function.

Methods

We prospectively enrolled 40 neurologically asymptomatic ESRD patients, 40 healthy controls, and 20 disease controls. All of the subjects underwent diffusion-tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI). We calculated measures of structural and functional connectivities based on DTI and rs-fMRI, respectively, and investigated differences therein between the ESRD patients and the healthy controls. We assessed cognitive function in the ESRD patients using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery.

Results

The ESRD patients exhibited decreased global structural and functional brain connectivities, as well as alterations of network hubs compared to the healthy controls and disease controls. About 70% of the ESRD patients had CI. Moreover, ESRD patients without CI exhibited decreased global connectivity and alterations of network hubs. Furthermore, there was a significant positive association between measures of brain connectivity and cognitive function.

Conclusions

We found that ESRD patients exhibited decreased structural and functional brain connectivities, and that there was a significant association between brain connectivity and cognitive function. These alterations in the brain network may contribute to the pathophysiological mechanism of CI in ESRD patients.

The gut microbiota-inflammation-brain axis in end-stage renal disease: perspectives from default mode network

The gut-brain axis in end-stage renal disease (ESRD) is attracting more and more attention. However, the mechanism of gut-brain axis based cognitive disorders in ESRD patients remains unclear. The purpose of this study was to investigate the linkages between the gut microbiota, inflammatory cytokines, brain default mode network (DMN) and cognitive function in ESRD patients. Methods: This prospective study enrolled 28 ESRD patients (13 males and 15 females, mean age of 44 ± 14 years) and 19 healthy controls (HCs) (12 males and 7 females, mean age of 44 ± 10 years). All subjects underwent stool microbiota analysis, blood inflammatory cytokines examination, brain MRI scans and cognitive assessments. Resting state functional MRI (rs-fMRI) data were used to construct DMN and graph theory was applied to characterize network topological properties. Two samples t-test was applied for the comparisons between ESRD and HCs. Correlation analysis and mediation analysis were conducted among factors with significant group differences. Results: ESRD patients displayed gut microbiota alterations, increased systemic inflammation and worse cognitive performance compared to HCs (all p < 0.05). Graph analysis revealed disrupted DMN topological organization, aberrant nodal centralities and functional connectivities (FCs) in ESRD patients relative to HCs (all p < 0.05, FDR corrected). Significant correlations were found between gut microbiota, inflammatory cytokines, DMN network measures and cognitive assessments. Mediation analysis found that gut microbiota alteration impaired DMN connectivity by increasing systemic inflammation. Conclusion: The present study first revealed gut microbiota alterations, systemic inflammation, DMN dissociation and cognitive dysfunction in ESRD patients simultaneously and further illuminated their inner relationship.

Moderately increased albuminuria, chronic kidney disease and incident dementia: the HUNT study

Background

Epidemiologic studies has shown an association of albuminuria and low estimated glomerular filtration rate (eGFR) with dementia, but the findings are inconsistent. This study examines the association between eGFR, MA with dementia and its subtypes: AD, VaD, a mixture of AD/VaD, and other dementias.

Methods

Data from the second wave of the HUNT 2 Study (1995–1997) were linked with a dementia register known as the Health and Memory Study (HMS) collected during 1995–2011 in Nord-Trøndelag County, Norway. Dementia was ascertained using World Health Organization’s ICD-10 criteria into subtypes: AD,VaD, mixed AD/VaD, and other dementia. eGFR and its association with dementia was examined in 48,508 participants of the HUNT Study, of which 668 were diagnosed with all-cause dementia. Association between MA and dementia were studied in a subset of 7024 participants, and 214 were diagnosed with all-cause dementia. Cox regression models were conducted analyzing the association between dementia and MA using albumin creatine ratio (ACR). Cox regression models and Fine-Gray models were used to examine the association between dementia and eGFR.

Results

A positive association was found between increasing ACR and dementia. ACR in the fourth quartile (> 1.78 mg/mmol) with increased hazard ratio of VaD, 3.97 (1.12 to 14.07), compared with ACR in the first quartile (<.53 mg/mmol). There was no association between eGFR and dementia or its subgroups.

Conclusions

Our results strengthens the hypothesis that vascular mechanisms may affect both kidney and brain as an association between MA and dementia was found. However, eGFR was not significantly associated with dementia independent of diabetes mellitus or hypertension.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1425-8) contains supplementary material, which is available to authorized users.

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.

How common are neurocognitive disorders in patients with chronic kidney disease and diabetes? Results from a cross-sectional study in a community cohort of patients in North Wales, UK

OBJECTIVE

Chronic kidney disease (CKD) affects nearly 9% of global populations and is strongly associated with older age. Neurocognitive disorders (NCDs), which include mild cognitive impairment and dementia, are rising as a result of ageing populations throughout the world. This investigation's aim is to report the frequency of mild to major NCD in a clinical cohort of adults with mild to moderate CKD and diabetes.

SETTING

Glan Clwyd District general Hospital, North Wales, UK.

PARTICIPANTS

We enrolled 178 patients with CKD and diabetes, aged 55 years and over with an estimated glomerular filtration rate <60 >15 mL/min/1.73 m², attending a specialist renal and diabetic outpatient clinic.

OUTCOME MEASURES

Frequency of mild and major NCD and the association with the stage of CKD was assessed in all patients attending the specialist clinic. The diagnosis of NCD was based on patient and informant interview, case note review, neuropsychological assessment and application of Diagnostic and Statistical Manual of Mental Disorders version 5.

RESULTS

This investigation found 86/178 (48%) of the cohort with an NCD ranging from mild (n=49) to major symptoms (n=37). No association was found with NCD and the stage of CKD. Mild and major NCD was associated poorer outcomes in several cognitive domains, including, language, executive, memory, fluency and attention function (p<0.05).

CONCLUSIONS

This is the first UK investigation to report that cognitive changes occur in a significant number of older adults with CKD and diabetes. The unexpected finding was that prior to cognitive assessment, not any of the cohort had a pre-existing diagnosis of cognitive impairment, suggesting that the current prevalence and incidence rates of NCD in the general population are possibly significantly underestimated. Our findings also suggest that the cognitive function of patients with CKD should be screened and monitored routinely as part of their overall care management.

Cognitive Impairment in Non-Dialysis-Dependent CKD and the Transition to Dialysis: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

BACKGROUND

Advanced chronic kidney disease is associated with elevated risk for cognitive impairment. However, it is not known whether and how cognitive impairment is associated with planning and preparation for end-stage renal disease.

STUDY DESIGN

Retrospective observational study.

SETTING & PARTICIPANTS

630 adults participating in the CRIC (Chronic Renal Insufficiency Cohort) Study who had cognitive assessments in late-stage CKD, defined as estimated glome-rular filtration rate ≤ 20mL/min/1.73m2, and subsequently initiated maintenance dialysis therapy.

PREDICTOR

Predialysis cognitive impairment, defined as a score on the Modified Mini-Mental State Examination lower than previously derived age-based threshold scores. Covariates included age, race/ethnicity, educational attainment, comorbid conditions, and health literacy.

OUTCOMES

Peritoneal dialysis (PD) as first dialysis modality, preemptive permanent access placement, venous catheter avoidance at dialysis therapy initiation, and preemptive wait-listing for a kidney transplant.

MEASUREMENTS

Multivariable-adjusted logistic regression.

RESULTS

Predialysis cognitive impairment was present in 117 (19%) participants. PD was the first dialysis modality among 16% of participants (n=100), 75% had preemptive access placed (n=473), 45% avoided using a venous catheter at dialysis therapy initiation (n=279), and 20% were preemptively wait-listed (n=126). Predialysis cognitive impairment was independently associated with 78% lower odds of PD as the first dialysis modality (adjusted OR [aOR], 0.22; 95% CI, 0.06-0.74; P=0.02) and 42% lower odds of venous catheter avoidance at dialysis therapy initiation (aOR, 0.58; 95% CI, 0.34-0.98; P=0.04). Predialysis cognitive impairment was not independently associated with preemptive permanent access placement or wait-listing.

LIMITATIONS

Potential unmeasured confounders; single measure of cognitive function.

CONCLUSIONS

Predialysis cognitive impairment is associated with a lower likelihood of PD as a first dialysis modality and of venous catheter avoidance at dialysis therapy initiation. Future studies may consider addressing cognitive function when testing strategies to improve patient transitions to dialysis therapy.

Cognition and renal function: findings from a Brazilian population

Introduction:

The prevalence of chronic kidney disease (CKD) is increasing, with a potential impact in the risk of acceleration of dementia. The potential association between glomerular filtration rate (eGFR) and cognitive performance was scarcely studied. The aim of this study was to evaluate cognitive performance levels across different degrees of kidney function.

Methods:

We analyzed 240 outpatients in a nephrology service, classified according to eGFR: Advanced (≤ 30ml/min/1.73m²), Moderate (30,1ml/min/1.73m² to ≤ 60ml/min/1.73m²), and Mild CKD (> 60ml/min/1.73m²). Word list memory, Semantic fluency, Mental State Mini Exam and Trail Making Test (TMT) were applied to evaluate cognitive performance. In the TMT, lower scores are associated with better cognition. In linear regression, cognitive function was considered as dependent variables while groups based on eGFR were considered explanatory variables. The group with eGFR > 60ml/min was the reference and models were adjusted for confounding factors.

Results:

In our population (n = 240) 64 patients (26.7%) were classified as having advanced, 98(40,8%) moderate, and 78(32,5%) mild. There was no statistical difference among them in MMSE or in the verbal fluency test. However, comparing to mild, patients with advanced CKD presented significantly worse cognitive performance measured by TMTA [50,8s ± 31.1s versus 66,6s ± 35,7s (p = 0.016)] and TMTB [92,7s ± 46,2s versus 162,4s ± 35,7s (p < 0.001)]. Significantly lower TMTB scores (CI95%) 33,0s (4,5-61,6s) were observed in patients with mild compared to advanced CKD in the multivariate analysis adjusting for age, education, sex, diabetes, and alcohol use.

Conclusion:

Advanced CKD is independently associated with poorer cognitive performance measured by an executive performance test compared to mild CKD.

Kidney function and cognitive decline in frail elderly: two faces of the same coin?

BACKGROUND AND AIMS

Cognitive and renal impairment are pervasive among elderly frails, a high-risk, geriatric sub-population with peculiar clinical characteristics. In a series of frail individuals with non-advanced chronic kidney disease (CKD), we aimed at assessing the entity of functional, general health and cognitive impairment and the possible relationship between these types of dysfunction and the severity of renal impairment.

METHODS

2229 geriatric subjects were screened for frailty and CKD. Severity of CKD was assessed by eGFR (CKD-EPI formula). Frailty was established by the Fried Index. Functional, general health and cognitive status were assessed by validated score measures.

RESULTS

Final analysis included 271 frail CKD subjects (162 women, 109 men). Mean eGFR was 64.25 ± 25.04 mL/min/1.73 m². Prevalence of mild-to-moderate CKD (stage 3-4) was 44%. Twenty-six percent of patients had severe cognitive impairment, while mild and moderate impairment was found in 7 and 67% of individuals, respectively. All subjects had poor functional and general health status. Cognitive capacities significantly decreased across CKD stages (p for trend < 0.0001). In fully adjusted multivariate analyses, cognitive status remained an independent predictor of eGFR (β = 0.465; p < 0.0001).

CONCLUSIONS

Mild-to-moderate CKD is highly pervasive among frail elderly individuals and the severity of renal dysfunction is independently correlated with that of cognitive impairment. Future studies are advocated to clarify whether the combination of kidney and mental dysfunction may portend a higher risk of worsen outcomes in this high-risk population.

Reduced White Matter Integrity With Cognitive Impairments in End Stage Renal Disease

Background: End-stage renal disease (ESRD) is a serious public health problem, which can often lead to multiorgan dysfunction, such as cerebrovascular disease and cognitive damage. It is essential to understand cognitive impairment in patients with ESRD to develop better ESRD treatment and prevent further cognitive impairment. Cognitive impairment is believed to be related to structural abnormalities in the brain. Purpose: To investigate white matter microstructural abnormalities in patients with ESRD using TBSS analysis of DTI and to explore the possible mechanisms underlying the impaired cognitive function. Materials and Methods: A TBSS analysis of DTI data was to investigate the microstructural changes in their WM over the whole brain. We chose the white matter tracts or regions with significantly reduced FA as the regions of interest (ROIs), Pearson's correlations were performed between clinical indicators (Mini-Mental State Examination (MMSE), digit span task scores, serum creatinine, blood urea nitrogen and hemodialysis duration) and the mean FA value of the ROIs in the ESRD patients. Results: Lower FA and higher MD, AD and RD values were observed in widespread and symmetrical WM in ESRD patients than healthy controls (HCs), Pearson correlation analysis revealed a significantly positive correlation between the Mini-Mental State Examination (MMSE) scores and FA values in the right corona radiata and left anterior thalamic radiation (ATR) and demonstrated a significantly negative correlation between FA values and the serum creatinine and blood urea nitrogen in the ATR (P < 0.01) in addition, digit span task scores positively correlate with the FA value in the left anterior rather than in the corona radiata. No cluster survived when we adopted the False Discovery Rate (FDR) correction to multiple comparisons. Conclusion: Our study indicate widespread impairment of the white matter in ESRD patients. Damage to the thalamic radiation and corona radiata may affect cognitive function in ESRD patients, the reduced integrity of ATR may tend to affect the working memory while the damage to the corona radiata may involve the executive function impaired in ESRD patients. The accumulation of serum creatinine and blood urea nitrogen may contribute to the WM impairment.