Chronic Kidney Disease and Cognitive Impairment

Clonal hematopoiesis of indeterminate potential is associated with reduced risk of cognitive impairment in patients with chronic kidney disease

INTRODUCTION

Clonal hematopoiesis of indeterminate potential (CHIP) and dementia disproportionately burden patients with chronic kidney disease (CKD). The association between CHIP and cognitive impairment in CKD patients is unknown.

METHODS

We conducted time-to-event analyses in up to 1452 older adults with CKD from the Chronic Renal Insufficiency Cohort who underwent CHIP gene sequencing. Cognition was assessed using four validated tests in up to 6 years mean follow-up time. Incident cognitive impairment was defined as a test score one standard deviation below the baseline mean.

RESULTS

Compared to non-carriers, CHIP carriers were markedly less likely to experience impairment in attention (adjusted hazard ratio [HR] [95% confidence interval {CI}] = 0.44 [0.26, 0.76], p = 0.003) and executive function (adjusted HR [95% CI] = 0.60 [0.37, 0.97], p = 0.04). There were no significant associations between CHIP and impairment in global cognition or verbal memory.

DISCUSSION

CHIP was associated with lower risks of impairment in attention and executive function among CKD patients.

HIGHLIGHTS

Our study is the first to examine the role of CHIP in cognitive decline in CKD. CHIP markedly decreased the risk of impairment in attention and executive function. CHIP was not associated with impairment in global cognition or verbal memory.

Unraveling of Molecular Mechanisms of Cognitive Frailty in Chronic Kidney Disease: How Exercise Makes a Difference

As our population ages, the medical challenges it faces become increasingly acute, with chronic kidney disease (CKD) becoming more prevalent among older adults. Frailty is alarmingly more common in CKD patients than in the general populace, putting the elderly at high risk of both physical and cognitive decline. CKD not only accelerates physical deterioration, but also heightens vascular dysfunction, calcification, arterial rigidity, systemic inflammation, oxidative stress, and cognitive impairment. Cognitive frailty, a distinct syndrome marked by cognitive deficits caused by physiological causes (excluding Alzheimer's and other dementias), is a critical concern. Although cognitive impairment has been well-studied, the molecular mechanisms driving cognitive frailty remain largely uncharted. Comprehensive interventions, including cutting-edge pharmaceuticals and lifestyle changes, are pivotal and effective, especially in the early stages of CKD. Recent research suggests that systematic exercise could counteract cognitive decline by improving brain blood flow, boosting neuroplasticity through the brain-derived neurotrophic factor (BDNF), and by triggering the release of neurotrophic factors such as insulin-like growth factor (IGF-1). This review delves into the molecular pathways of cognitive frailty in CKD, identifies key risk factors, and highlights therapeutic approaches, particularly the potent role of exercise in enhancing cognitive health.

Risk Factors for Natural Cause Mortality in Schizophrenia

Importance

Schizophrenia is associated with premature mortality from mostly natural causes. Decreased cognitive functioning has been identified as a determinant of mortality in the general population. However, there have been few prospective studies of this issue in persons with schizophrenia.

Objective

To examine whether lower cognitive functioning is a risk factor for natural cause mortality in schizophrenia.

Design, Setting, and Participants

This prospective cohort study included persons with schizophrenia or schizoaffective disorder enrolled between February 1, 1999, and December 31, 2022, at a nonprofit psychiatric system in Baltimore, Maryland. Participants were evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and other clinical measures.

Exposure

Natural cause mortality.

Main Outcomes and Measures

Associations of cognitive function, obesity, tobacco smoking, and medical conditions with natural cause mortality were evaluated using Cox proportional hazards regression models.

Results

Of the 844 participants enrolled (mean [SD] age, 39.6 [12.1] years; 533 male [63.2%]), 158 (18.7%) died of natural causes during a median follow-up of 14.4 years (range, 7.0 days to 23.9 years). The most significant factor associated with mortality was lower cognitive functioning as measured by the RBANS (Cox coefficient, -0.04; 95% CI, -0.05 to -0.03; z = -5.72; adjusted P < .001). Additional factors independently associated with mortality included the diagnosis of an autoimmune disorder (hazard ratio [HR], 2.86; 95% CI, 1.83-4.47; z = 4.62; adjusted P < .001), tobacco smoking (HR, 2.26; 95% CI, 1.55-3.30; z = 4.23; adjusted P < .001), diagnosis of chronic obstructive pulmonary disease (HR, 3.31; 95% CI, 1.69-6.49; z = 3.48; adjusted P = .006), body mass index as a continuous variable (HR, 1.06; 95% CI, 1.02-1.09; z = 3.30; adjusted P = .01), diagnosis of a cardiac rhythm disorder (HR, 2.56; 95% CI, 1.40-4.69; z = 3.06; adjusted P = .02), and being divorced or separated (HR, 1.80; 95% CI, 1.22-2.65; z = 2.97; adjusted P = .02). An RBANS score below the 50th percentile displayed a joint association with being a smoker, having an elevated body mass index, and having a diagnosis of an autoimmune or a cardiac rhythm disorder.

Conclusions and Relevance

In this prospective cohort study, lower cognitive functioning was a risk factor for natural cause mortality in schizophrenia. Efforts should be directed at methods to improve cognitive functioning, particularly among individuals with additional risk factors.

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.

Association between TMSE/MoCA and MIS/NAF in ESKD patients undergoing hemodialysis: a cross-sectional study

BACKGROUND

Both cognitive impairment and malnutrition are common in hemodialysis (HD) patients and are associated with increased hospitalization rates, infection, poor clinical outcomes, and mortality. The study investigated the association between cognitive and nutrition status among end-stage kidney disease (ESKD) patients undergoing hemodialysis.

METHODS

In this cross-sectional study, we enrolled 115 patients with ESKD who underwent regular hemodialysis (HD). Data collection included the use of screening tools for mild cognitive impairment (MCI), specifically Thai Mental State Examination (TMSE) and Montreal Cognitive Assessment (MoCA). In addition, we collected data using nutritional screening tools including Malnutrition Inflammation Score (MIS) and Nutrition Alert Form (NAF). Our primary outcome was to demonstrate whether there was a relationship between TMSE/MoCA and MIS/NAF scores in this population. Secondary outcomes were a prevalence of MCI and malnutrition status in ESKD patients, an association between TMSE and MoCA with other surrogate nutritional markers, and factors affecting MCI in such patients.

RESULTS

A total of 109 patients undergoing HD completed our protocol. Their mean age was 63.42 (± 15.82) years, and 51.38% were male. Mean TMSE and MoCA were 23.98 (± 5.06) points and 18.3 (± 6.40) points, respectively. The prevalence of TMSE ≤ 23 and MoCA ≤ 24 were 39.45% and 83.49%, respectively. TMSE had a statistically significant negative correlation with MIS (R2 = 0.16, p < 0.001) and NAF. MoCA also negatively correlated with MIS and NAF. The age, total educational year, the status of whether having a caregiver, serum albumin, serum phosphorus level, handgrip strength, and lean mass tissue were correlated with TMSE.

CONCLUSION

Nutritional parameters, including MIS score, NAF score, serum albumin, lean tissue mass, and lean tissue index, significantly correlate with TMSE and MoCA.

The effect of changes in intra-compartmental bioimpedance measurements with early intra-dialytic hypotension during haemodialysis

INTRODUCTION

Intra-dialytic hypotension (IDH) remains the commonest problem associated with routine haemodialysis treatments. Fluid shifts from intracellular(ICW) and extracellular(ECW) compartments to refill plasma volume during haemodialysis with ultrafiltration.

METHODS

We studied the effect of relative changes in ICW and ECW indifferent body segments using multifrequency segmental bioimpedance during haemodialysis and IDH episodes.

RESULTS

Of 42 haemodialysis patients,16 patients (38.1%) developed IDH within the first hour of dialysis. Patients with and without early IDH were well-matched for demographics and starting bioimpedance measurements. However, after 60 min, the relative change in in ECW/ICW ratio between the non-fistula arm and leg was significantly different for the early IDH group median -1.07 (-3.33 to 0.8) versus 0.61 (-0.78 to 1.8), p < 0.05, whereas there no differences in ultrafiltration rate, relative blood volume monitoring or on-line clearance.

CONCLUSION

Monitoring serial changes in fluid status in different body compartments with bioimpedance may potentially prevent IDH in the future.

Investigation of accordance between nutritional assessment tools, and bio-electrical impedance-derived phase angle, with the global leadership initiative on malnutrition criteria in hemodialysis patients

BACKGROUND

Malnutrition (MN) is a major health concern for patients with chronic kidney disease (CKD) who receive maintenance hemodialysis (MHD). These patients are particularly vulnerable to MN due to their compromised health status, which in turn increases the risk of morbidity and mortality. However, there is limited evidence on the use of reliable and effective tools for assessing MN in this population. This lack of sufficient data highlights the crucial need to assess MN within these patients, considering the significant mortality risk it poses. The first aim of this study was to compare the concurrent validity of three nutritional methods: the 7-point Subjective Global Assessment (7p-SGA), the Nutritional Risk Index (NRI), and the Nutritional Risk Screening from 2002 (NRS-2002) with the Global Leadership Initiative on Malnutrition (GLIM) criteria in MHD patients. The second aim was to investigate the advantage of the bio-electrical impedance-derived phase angle (PhA) in predicting MN.

METHODS

one hundred sixty-eight outpatients (31% women) with a mean age of 56.9 ± 14.7 years and a median dialysis vintage of 48 months were included in this retrospective study. Nutritional scores, anthropometric measurements, biological markers, and body composition parameters were collected.

RESULTS

According to GLIM standards, MN was identified in 80% of these patients. Using logistic regression (LR) analysis, all nutritional scores were significantly associated with GLIM criteria, with optimal sensitivity (94.4%) and specificity (85.7%) for 7p-SGA and NRI, respectively. For discriminating the nutritional risk, the GLIM criteria demonstrated a good agreement with 7p-SGA (Kappa concordance coefficient (κ) = 0.677, p-value<0.001) with a good level of accuracy (Area Under the Curve (AUC) = 0.841; 95% Confidence Interval (CI) = 0.705-0.977; p-value <0.001) when compared to the NRI and NRS-2002 (κ = 0.522, p-value<0.001 and κ = 0.411, p-value = 0.006, respectively). An excellent accuracy was found between PhA and the GLIM-defined MN, with an optimal cut-off value of 5.5° for males and 4.5° for females. The LR showed that arm circumference is the parameter that most influences the decrease of PhA (odds ratio 2.710, 95% CI = 1.597-4.597, p-value <0.001).

CONCLUSION

Based on the results of the present study, 7p-SGA is the most sensitive score in identifying MN diagnosed by GLIM criteria. Nonetheless, NRI exhibits greater specificity. PhA is a valuable marker for MN in MHD patients.

Depressive symptom mediates the association between the number of chronic diseases and cognitive impairment: a multi-center cross-sectional study based on community older adults

Objective

The purpose of this study was to understand the relationship between the multiple chronic conditions (MCC), mental health and cognitive function of older adults in the community, and to propose a hypothesis that depressive symptom mediate the number of chronic diseases and cognitive impairment in older adults.

Method

Participants aged 65 years and older from 35 communities in 14 cities in Guangxi, China were recruited. The residents' depressive symptom (PHQ-9) and cognitive status (AD-8) were evaluated, Chi-square test was used to explore the effects of different socio-demographic characteristics on depressive symptom and cognitive impairment. Pearson correlation analysis and the process model 4 were used to explore the relationship between the number of chronic diseases, depressive symptom and cognitive impairment.

Result

A total of 11,582 older adults were included in our analysis. The rate of MCC reaching 26.53%. Hypertension combined with diabetes accounts for the highest proportion of two chronic diseases (13.2%). Among the combination of three chronic diseases, the highest incidence of coexisting hypertension combined with cervical/lumbar spondylosis, and rheumatoid arthritis (7.1%). In this study, depression symptoms accounted for 12.9% of older adults aged 65 and above, and cognitive impairment accounted for 27.4%. Female, older age, reside in urban areas, lower educational levels, no spouse, live alone, and MCC were risk factors for depressive symptom and cognitive impairment in older adults (P<0.05). Depressive symptom had a mediating effect in the number of chronic diseases and cognitive impairment, and the mediating effect (1.109) accounted for 44.13% of the total effect (0.247).

Conclusion

The mental health of the older adult needs to be taken seriously, and improving depressive symptom can reduce the occurrence of cognitive impairment in older patients with MCC to a certain extent.

Assessment of Cognitive Flexibility in Jordanian Diabetic Patients by Wisconsin Card Sorting and Trail Making Tests: Implications with Demographic, Anthropometric and Therapeutic Variables

Purpose

Cognitive flexibility is a mental ability that aids in smoothly alternating between them tasks in the brain. Diabetes Mellitus (DM) is a, common disorder that has been associated with impairments in cognitive functions. This research is a retrospective case-control study aimed at establishing a clear relationship between cognitive flexibility and diabetes among Jordanians, considering demographic, anthropometric, and therapeutic variables.

Patients and Methods

The Wisconsin Card Sorting Test (WCST)-64 item and the Trail Making Test (TMT) assessed cognitive flexibility in 268 people with diabetes and healthy control. Demographic, therapeutic data were collected. We also measured waist-to-hip ratio (WHR) and body mass index (BMI). As the variables were non-normally distributed, non-parametric statistical tests were used to examine differences (Kruskal-Wallis) and correlation (Spearman) between variables.

Results

The patient group did worse on the WCST In contrast to the control group, patients exhibited more significant delays for both Part A and Part B of the TMT (p<0.05). Males had higher WCST conceptual level responses than females. In addition, participants with professional jobs showed less delay in TMT Part A (p<0.05). Age was positively correlated with WCST's total errors and TMT's Parts A and B (p<0.05). BMI was negatively correlated with the WCST's conceptual level of responses and positively correlated with TMT's Part B (p<0.05). In addition, urea and albumin levels were positively correlated with TMT's Part A (p<0.05). Furthermore, creatinine was positively correlated with WCST's total errors and TMT's Part A (p<0.05).

Conclusion

Some measures of cognitive flexibility are associated with DM status in the studied sample of Jordanians and other variables (educational levels, occupation, lifestyle, average duration of illness, and age).

Mid- and Late-Life Chronic Kidney Disease Is Associated with Parkinson's Disease, Not with an Increased Risk of Alzheimer's Disease

Chronic kidney disease (CKD) is strongly associated with dementia. However, its independent association with Alzheimer's or Parkinson's disease remains unclear. This study investigated the prospective association of patients with CKD aged ≥55 years with an increased risk of Alzheimer's or Parkinson's disease. We conducted a retrospective cohort analysis using a national cohort sample of approximately one million patients. Primary outcome indicators measured included incidence of all-cause dementia, Alzheimer's disease, and Parkinson's disease events using person-years at risk. The hazard ratio was adjusted using the Cox proportional hazards model. We included 952 patients without CKD and 476 with CKD over 55 years using propensity score matching. The CKD group exhibited higher incidences of all-cause dementia, Parkinson's disease, and Alzheimer's disease than the non-CKD group. Furthermore, the CKD group had an elevated risk of all-cause dementia and a significantly increased risk of Parkinson's disease, especially among older women. Notably, the risk of Parkinson's disease was higher within the first 3 years of CKD diagnosis. These findings emphasize the link between CKD in mid- and late-life individuals and a higher incidence of all-cause dementia and Parkinson's disease rather than Alzheimer's disease.

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.

Connecting the Dots: The Cerebral Lymphatic System as a Bridge Between the Central Nervous System and Peripheral System in Health and Disease

As a recently discovered waste removal system in the brain, cerebral lymphatic system is thought to play an important role in regulating the homeostasis of the central nervous system. Currently, more and more attention is being focused on the cerebral lymphatic system. Further understanding of the structural and functional characteristics of cerebral lymphatic system is essential to better understand the pathogenesis of diseases and to explore therapeutic approaches. In this review, we summarize the structural components and functional characteristics of cerebral lymphatic system. More importantly, it is closely associated with peripheral system diseases in the gastrointestinal tract, liver, and kidney. However, there is still a gap in the study of the cerebral lymphatic system. However, we believe that it is a critical mediator of the interactions between the central nervous system and the peripheral system.

A Correlative Relationship Between Heart Failure and Cognitive Impairment: A Narrative Review

Heart failure (HF) is a chronic condition affecting millions of people worldwide. While the cardinal manifestations of HF are related to the cardiovascular system, it has become progressively evident that mild cognitive impairment (MCI) is also a significant complication of the disease. In fact, a significant number of patients with HF may experience MCI, which can manifest as deficits in attention, memory, executive function, and processing speed. The mechanisms responsible for cognitive dysfunction in HF are intricate and multifactorial. Possible factors contributing to this condition include decreased cerebral blood flow, thrombogenicity associated with HF, systemic inflammatory conditions, and proteotoxicity. MCI in HF has significant clinical implications, as it is linked to poorer quality of life, increased morbidity and mortality, and higher healthcare costs. Additionally, MCI can disrupt self-care behaviors, adherence to medication, and decision-making abilities, all of which are crucial for effectively managing HF. However, there is currently no gold standard diagnostic tool and follow-up strategy for MCI in HF patients. There is limited knowledge on the prevention and treatment of MCI. In conclusion, MCI is a common and clinically important complication of HF. Considering the substantial influence of MCI on patient outcomes, it is imperative for healthcare providers to be cognizant of this issue and integrate cognitive screening and management strategies into the care of HF patients.

Screening of cognitive performance in kidney transplant recipients: a mini review

Why should we screen?

The prevalence of cognitive impairment in kidney transplant recipients (KTRs) is up to 58%. The 10-year graft loss and mortality rates are above 30% and 50%, respectively, and executive malfunctioning increases disadvantageous outcomes.

What causes cognitive impairment in KTRs?

Strong risk factors are older age and chronic kidney disease. However, causes are multifactorial and include cardiovascular, cerebrovascular, neurodegenerative, inflammatory, uremic, psychiatric, and lifestyle-related susceptibilities.

How should we screen?

KTR-specific validated instruments or strategies do not exist. The central element should be a multidomain cognitive screening test that is sensitive to mild cognitive impairment, corrects for age and education, and includes executive functions testing. Cognitive trajectories, effects on everyday life and psychiatric comorbidities should be assessed by integrating the perspectives of both patients and knowledgeable informants.

When should we screen?

Screening should not be postponed if there is suspicion of impaired cognition. Different time points after transplantation tend to have their own characteristics.

Who should conduct the screening?

Screening should not be limited to specialists. It can be carried out by any healthcare professional who has received a limited amount of training.

What are the benefits of screening?

Screening does not provide a diagnosis. However, suggestive results change care in multiple ways. Goals are: Initiation of professional dementia work-up, securing of adherence, anticipation of potential complications (delirium, falls, frailty, functional impairment, malnutrition, etc.), mitigation of behavioral disorders, adjustment of diagnostic and therapeutic "load", reduction of caregiver burden and meeting of changing needs. We summarize data on the prevalence, risk factors and sequelae of cognitive impairment in KTRs. We also discuss the requirements for appropriate screening strategies and provide guiding principles regarding appropriate and safe care.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Risk of New-Onset Dementia in Patients with Chronic Kidney Disease on Statin Users: A Population-Based Cohort Study

Patients with chronic kidney disease (CKD) are at a higher risk for developing dementia than the general population. Clinical studies have investigated the effects of statin use on new-onset dementia (NOD) in patients with CKD; however, the findings are inconsistent. This study examines the association between the use of statins and NOD in patients with CKD. We conducted a nationwide retrospective cohort study using the Taiwan Health Insurance Review and Assessment Service database (2003–2016). The primary outcome assessed the risk of incident dementia by estimating the hazard ratios and 95% confidence intervals. Therefore, multiple Cox regression models were conducted to analyse the association between statin use and NOD in patients with CKD. There were 24,090 participants with statin use and 28,049 participants without statin use in patients with new-diagnosed CKD; the NOD event was 1390 and 1608, respectively. There was a trend of reduction association between statin users and NOD events after adjusted sex, age, comorbidities, and concurrent medication (adjusted HR 0.93, 95% CI 0.87 to 1.00) in the 14 years of the follow-up. Sensitivity test for the propensity score 1:1 matched analyses showed similar results (adjusted HR 0.91, 95% CI 0.81 to 1.02). The subgroup analysis also identified the use of statins as having a trend against developing NOD in patients with hypertension. In conclusion, statin therapy may effectively reduce the risk of NOD in patients with CKD. More studies are needed to credibly evaluate the effects of statin therapy on the prevention of NOD in patients with CKD.

Cognitive Impairment, Frailty, and Adverse Outcomes Among Prevalent Hemodialysis Recipients: Results From a Large Prospective Cohort Study in the United Kingdom

Rationale & Objective

Frailty and cognitive impairment are common in hemodialysis recipients and have been associated with high mortality. There is considerable heterogeneity in frailty reporting, with little comparison between commonly used frailty tools and little exploration of the interplay between cognition and frailty. The aims were to explore the relationship between frailty scores and cognition and their associations with hospitalization and mortality.

Study Design

Prospective cohort study.

Setting & Population

Prevalent hemodialysis recipients linked to national datasets for hospitalization and mortality.

Predictors

Montreal Cognitive Assessment (MoCA), Frailty Phenotype, Frailty Index (FI), Edmonton Frailty Scale, and Clinical Frailty Scale (CFS) were performed at baseline. Cognitive impairment was defined as MoCA scores of <26, or <21 in dexterity impairment, <18 in visual impairment.

Outcomes

Mortality, hospitalization.

Analytical Approach

Cox proportional hazards model for mortality, censored for end of follow-up. Negative binomial regression for admission rates, censored for death/end of follow-up.

Results

In total, 448 participants were recruited with valid MoCAs and followed up for a median of 685 days. There were 103 (23%) deaths and 1,120 admissions of at least one night. Cognitive impairment was identified in 346 (77.2%) participants. Increasing frailty by all definitions was associated with poorer cognition. Cognition was not associated with mortality (HR, 0.99; 95% CI, 0.95-1.03; P = 0.41) or hospitalization (IRR, 1.01; 95% CI, 0.99-1.04; P = 0.39) on multivariable analyses. There were interactions between MoCA scores and increasing frailty by FI (P = 0.002) and Clinical Frailty Scale (P = 0.005); admissions were highest when both MoCA and frailty scores were high, and when both scores were low.

Limitations

As frailty is a dynamic state, a single cross-sectional assessment may not accurately reflect its year-to-year variability. In addition, these findings are in maintenance dialysis and may not be transferable to incident hemodialysis. There were small variations in application of frailty tool criteria from other studies, which may have influenced the results.

Conclusions

Cognitive impairment is highly prevalent in this hemodialysis cohort. The interaction between cognition and frailty on rates of admission suggests the MoCA offers value in identifying higher risk hemodialysis populations with both high and low degrees of frailty.

Addressing Cognitive Function and Psychological Well-Being in Chronic Kidney Disease: A Systematic Review on the Use of Technology-Based Interventions

Patients with chronic kidney disease (CKD) are at risk of both a gradual decline in cognitive function and an increase in psychological distress. This includes symptoms of anxiety, depression, and sleep disturbances, all of which are factors that have been associated with increased morbidity and mortality. In response, we are now seeing that interventions based on new digital technologies are increasingly used in order to optimize patients' quality of life. Systematic research of the literature on electronic databases (MEDLINE/PubMed, Scopus, Web of Science, and PsycInfo/ProQuest) covering the period from 2012 to 2022 was conducted in order to methodically review the existing evidence regarding the implementation and effectiveness of technology-based interventions in the management of cognitive and psychological well-being symptoms in patients with CKD. A total of 739 articles were retrieved, 13 of which are included in the present review. All the studies focused on the usability, acceptability, and feasibility of technology-based interventions aimed at psychological symptoms, with no studies targeting cognitive functioning. Technology-based interventions offer feelings of safety, fun, and satisfaction, and they also have the potential to improve CKD patients' health outcomes regarding their psychological well-being. The diverseness of technologies allows an approximation towards the identification of those types of technologies most frequently used, as well as the symptoms targeted. There was considerable heterogeneity in the types of technologies used for interventions in so few studies, making it difficult to draw conclusive findings with regard to their efficiency. In order to adequately assess the technology-based health interventions effect, future lines of research should consider designing non-pharmacological treatments for the improvement of cognitive and psychological symptoms in this type of patient.

Diffusion tensor imaging of the brain white matter microstructure in patients with chronic kidney disease and its correlation with cognition

Purpose

In individuals with chronic kidney disease (CKD), neurological damage is commonly observed. This neurodegeneration is closely linked to microstructural damage to the brain white matter due to the high incidence of cognitive dysfunction. However, the specific pathogenesis of CKD nephropathy caused by cognitive system developmental disorders remains unclear. This study aimed to examine the correlation between cognitive impairment and diffusion parameters obtained on diffusion tensor imaging (DTI) of abnormal white matter tracts in CKD patients.

Methods

Sixty-four patients with CKD were divided into the non-dialysis-dependent CKD (NDD-CKD) group (N = 26) and dialysis-dependent CKD (DD-CKD) group (N = 38) according to the estimated glomerular filtration rate, whereas 43 healthy control subjects (normal control [NC]) were included and underwent cranial magnetic resonance imaging during the same period. Differences in the abnormal white matter microstructure and correlations between them and cognitive scores were assessed using several parameters between the groups.

Results

There were more extensive peri-lesions and distant white matter microstructural changes in the DD-CKD and NDD-CKD groups than in the NC group. DTI diffusion parameters in abnormal white matter regions were associated with impaired cognitive function in CKD patients. The DD-CKD group had worse cognitive function and more severe microstructural damage in the cerebral white matter than the NDD-CKD group.

Conclusion

CKD patients showed cognitive impairment and changes in the brain white matter microstructure; CKD can lead to extensive white matter tract damage. Additionally, diffusion parameters can be used as a complement to describe structural brain damage in CKD patients.

Prevalence and associated factors of cognitive frailty in older patients with chronic kidney disease: a cross-sectional study

BACKGROUND

Chronic kidney disease (CKD) is prevalent in older adults. In the aging CKD population, cognitive frailty is more common, but its prevalence and associated risk factors need to be further investigated.

METHODS

This is a cross-sectional study that enrolled patients aged ≥ 60 years with a diagnosis of CKD from January 2018 to February 2021. Patients were assessed for frailty and cognition with the FRAIL and the Mini-Mental State Examination (MMSE) scales and were divided into the cognitive frailty and non-cognitive frailty groups. Risk factors for cognitive frailty were identified by univariate and multivariate logistic regression analyses. A prediction model for cognitive frailty was built and a nomogram was plotted. The performance of the nomogram was evaluated by using a concordance index (C-index) and calibration plots.

RESULTS

A total of 1015 older patients with CKD were enrolled, among whom 607 (59.8%) were males and 408 (40.2%) were females, with an age ranging from 60 to 98 years, and an cognitive frailty prevalence of 15.2%. The prevalence of cognitive frailty varied among the CKD stages 1-5, with rates of 4.7%, 7.5%, 13.8%, 18.5%, and 21.4%, respectively. Multivariate logistic regression analysis showed that age (OR = 1.11, 95%CI 1.08-1.14, p < 0.001), depression (OR = 2.52, 95%CI 1.54-4.11, p < 0.001), low social support (OR = 2.08, 95%CI 1.28-3.39, p = 0.003), Charlson comorbidity index (CCI) (OR = 1.92, 95%CI 1.70-2.18, p < 0.001), eGFR (OR = 0.98, 95%CI 0.96-0.99, p < 0.001) and albuminuria (OR = 5.93, 95%CI 3.28-10.74, p < 0.001) were independent risk factors affecting the association with cognitive frailty in older patients with CKD. A nomogram for assessing cognitive frailty was established and well-calibrated with a C-index of 0.91 (95%CI 0.89-0.94).

CONCLUSIONS

The prevalence of cognitive frailty was higher in older patients having CKD. Advanced age, comorbidity, depression, low social support, eGFR and albuminuria were independent risk factors for CKD accompanied with cognitive frailty.

The Intersection of SGLT2 Inhibitors, Cognitive Impairment, and CKD

Impairment in cognition and decline in kidney function often converge in the aging individual with chronic kidney disease (CKD). Cognitive impairment (CI) may be preventable through modification of health behaviors and risk factors that contribute to the vascular disease burden. CKD patients often have multiple coexisting comorbid conditions contributing to vascular risk. These comorbidities include hypertension, diabetes, cerebrovascular disease, and cardiovascular disease. Emerging evidence suggests that the management and prevention of vascular risk factors and cardiovascular diseases may indirectly contribute to the prevention of CI in CKD. Sodium glucose transport protein 2 inhibitors (SGLT2i) are emerging as the standard of care for selected individuals with CKD, type 2 diabetes (T2DM), and heart failure with rapidly expanding indications being actively investigated. In this narrative review, we examine the intriguing hypothesis that SGLT2i demonstrate potential disease modifying properties in CI among individuals with CKD.

Effect of exercise on cognitive impairment in patients undergoing haemodialyses: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

The influence of exercise on cognition in patients undergoing haemodialysis has been examined. However, evidence elucidating the effects in this patient group is scarce.

OBJECTIVE

To examine the effect of exercise on cognitive impairment in patients undergoing haemodialysis and provide insight into the effects of various characteristics of exercise on cognitive impairment in this population.

DESIGN

A systematic review and meta-analysis, following the guidance of PRISMA was undertaken.

PARTICIPANTS

Adult patients undergoing haemodialysis.

RESULTS

This review found that exercise significantly improved cognitive impairment in patients undergoing haemodialysis (SMD = 0.37, 95% CI: 0.13, 0.60, p = 0.002). Subgroup analyses demonstrated that both intradialytic exercise (SMD = 0.82, 95% CI: 0.37, 1.26, p < 0.001) and interdialytic exercise (SMD = 0.24, 95% CI: 0.01, 0.47, p = 0.038), exercise for 16 weeks or over (SMD = 0.33, 95% CI: 0.07, 0.58, p = 0.012), and lasting for more than 30 minutes (SMD = 0.52, 95% CI: 0.17, 0.86, p = 0.004) significantly alleviated cognitive impairment. The effect of exercise on cognitive impairment in patients less than 65 years of age (SMD = 0.39, 95% CI: 0.10, 0.68, p = 0.009) was significantly better than those over 65.

CONCLUSION

Exercise significantly improves cognitive impairment in patients undergoing haemodialysis. Both Intradialytic and interdialytic exercise of at least 30 minutes duration, 3 times weekly, and at least for 16 weeks may play a significant role in alleviating cognitive impairment in patients under 65 years of age.

Prognostic interplay of kidney function with sarcopenia, anemia, disability and cognitive impairment. The GLISTEN study

BACKGROUND

Interactions between chronic kidney disease (CKD) and several comorbidities may potentially affect prognosis of older hospitalized patients. This study aims at evaluating the prognostic interactions between estimated glomerular filtration rate (eGFR), anemia, sarcopenia, functional and cognitive dysfunction, and 3-year mortality among older patients discharged from acute care hospitals.

METHODS

Our series consisted of 504 older adults enrolled in a multicenter observational study carried out in twelve Acute Geriatric and Internal Medicine wards throughout Italy. CKD was defined as an eGFR< 60 ml/min/1.73 m². Anemia, Short Portable Status Mental Questionnaire (SPMSQ), Basic Activities of Daily Living (BADL), sarcopenia, and Charlson index were considered in the analysis. 3-year survival was investigated by Cox regression and prognostic interactions among study variables were assessed by survival tree analysis. Accuracy of different survival models was investigated by C-index.

RESULTS

eGFR < 30 mL/min/1.73 m², anemia, sarcopenia, SPMSQ ≥ 5, and impairment in 1 or more BADL were significantly associated with mortality. Survival tree analysis showed that patients with eGFR < 35.32 ml/min/1.73 m² and SPMSQ ≥ 5 had the highest risk of mortality [hazard ratio (HR): 5.49, 95%CI: 3.04-9.94] followed by those with eGFR < 35.32 ml/min/1.73 m², hemoglobin < 11.95 g/dL and SPMSQ < 5 (HR:3.65; 95%CI: 2.21-6.02) and those with eGFR 35.32-47.99 ml/min/1.73 m² and sarcopenia (HR:3.65; 95%CI: 1.99-6.69). Survival tree leaf node membership had good accuracy in predicting the study outcome (C-index: 0.73, 95%CI:0.70-0.76).

CONCLUSIONS

Interactions among study risk factors designed distinct risk profiles in older patients discharged from acute care hospitals, that may help identify patients needing targeted interventions and appropriate follow-up after discharge.

Processing speed is affected by early impairment in kidney function in the general elder population

Background

Chronic kidney disease, cardiovascular disease, and cognitive dysfunction are common in the elder population. There is evidence of a connection between these conditions, possibly by a shared vascular pathogenesis. Processing speed is commonly impaired in cerebrovascular disease.

Methods

The data was obtained from the population based study “Good aging in Skåne” (GÅS), and included 905 individuals (mean age = 68 years). We investigated the impact of impaired kidney function at baseline on the development of dementia, MCI, and impairment in specific cognitive domains at follow up 6 years later, using logistic regression models. Impaired kidney function was defined as GFR < 60 ml/min/1,73 m². GFR was estimated from creatinine and cystatin C, using the CKD-EPI formula. Function in the cognitive domains learning and memory, language, complex attention, executive function, perceptual-motor, as well as meta-memory, and global cognitive function, was assessed using a neuropsychological test battery consisting of 12 tests. We compared the test results from follow up, with the results obtained at baseline, using linear regression models in order to assess changes in performance in cognitive domains.

Results

At follow up, 14 and 158 participants had developed dementia and MCI, respectively. We did not find evidence that moderately impaired eGFR at baseline increased the odds of dementia or MCI. A decline in processing speed was associated with impaired kidney function.

Conclusions

The effect on processing speed could represent early vascular implications on cognition. Even at moderately impaired kidney function, overview of cardiovascular risk factors could potentially prevent further cognitive impairment.

Evaluation of cerebral dysfunction in patients with chronic kidney disease using neuropsychometric and neurophysiological tests

Background

Uremic encephalopathy is defined as cerebral dysfunction due to toxin accumulation in patients with chronic kidney disease (CKD). This condition is characterized by subtle to florid symptoms, and its clinical course is always progressive when untreated but partially reversible with renal replacement therapy. While no test exists to measure subclinical uremic encephalopathy, two tests have been validated to measure minimal hepatic encephalopathy: the critical flicker frequency (CFF) test and the psychometric hepatic encephalopathy score (PHES).

Objective

To use CFF and PHES to measure the prevalence of cerebral dysfunction in individuals with CKD.

Methods

This cross-sectional study included a total of 69 patients with stage-5 CKD. Cutoff points for minimal encephalopathy were established using existing clinical guidelines: ≤39 Hz for CFF and < −4 for PHES. All participants were also screened for cognitive function and depression.

Results

Eighteen cases (26.1%) of cerebral dysfunction linked to uremic encephalopathy were detected with CFF, while twelve (17.4%) were detected by PHES; only six cases (8.7%) were diagnosed by both methods. Half of the cases (50%) had diabetes, and 61% were on hemodialysis. Cognitive function scores did not differ significantly between those receiving dialysis, hemodialysis, or no renal replacement therapy.

Conclusions

It is essential to identify cerebral dysfunction when uremic encephalopathy is in early subclinical stages to reduce preventable events as traffic and work accidents.