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Open Access

Peer-reviewed

Research Article

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

  • Jialing Zhang,

    Roles Data curation, Formal analysis, Methodology, Writing – original draft

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Leiyun Wu,

    Roles Data curation

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Peixin Wang,

    Roles Data curation

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Yajing Pan,

    Roles Data curation

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Xingtong Dong,

    Roles Data curation

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Linpei Jia,

    Roles Data curation

    Affiliation Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯
  • Aihua Zhang

    Roles Conceptualization, Formal analysis, Funding acquisition, Methodology, Writing – review & editing

    rosezhang998@hotmail.com

    Affiliations Department of Nephrology, Xuanwu Hospital, Capital Medical University, Beijing, China, The National Clinical Research Center for Geriatric Disease, Xuanwu Hospital, Capital Medical University, Beijing, China

    ⨯

Abstract

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)

Citation: Zhang J, Wu L, Wang P, Pan Y, Dong X, Jia L, et al. (2024) Prevalence of cognitive impairment and its predictors among chronic kidney disease patients: A systematic review and meta-analysis. PLoS ONE 19(6): e0304762. https://doi.org/10.1371/journal.pone.0304762

Editor: Ala Abdul-Hussein Mahdi SH. Ali, Baghdad Medical City, IRAQ

Received: October 12, 2023; Accepted: May 19, 2024; Published: June 3, 2024

Copyright: © 2024 Zhang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This study was supported by the Xuanwu Hospital Huizhi talent leader training program, and the funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Introduction

Chronic kidney disease (CKD) is one of the most common causes of morbidity and mortality worldwide [1]. CKD is identified based on the degree of kidney damage or by a measured glomerular filtration rate (GFR) ≤60 mL/min/1.73 m2 for more than 3 months [2]. The global prevalence of CKD was estimated to be 13.4% [3]. Cognition impairment (CI) in patients with CKD has become a major concern. It is well established that CI may positively correlate with the degree of decline in residual renal function [4], even in early CKD [5]. A decrease in multiple cognitive functions, including processing, memory, and executive function, has been shown in CKD patients [6]. Moreover, magnetic resonance imaging techniques showed that hippocampus atrophy, cortical atrophy, and white matter lesions are frequent in CKD patients, and are likely to lead to cognitive disturbance [7, 8].

CI was independently associated with mortality in elderly hemodialysis (HD) patients [9]. However, it should be noted that the prevalence of CI in patients with CKD are variable. Kurella et al. reported a 23–28% prevalence of CI in stage 3–4 CKD patients [10], nearly 87% in patients with HD [11], and 50% in patients with peritoneal dialysis (PD) [12]. The prevalence of CI in CKD patients varies widely around the world, reaching 58% in the USA [13], 49.9% in Asia [12], 30.3% in Europe [14], and 35% in Africa [15]. However, quantitative studies on the current epidemiology of CI in patients with CKD are few.

The pathophysiology of cognitive decline in CKD patients is complex. Various clinical factors could contribute to CI in CKD, including traditional risk factors (e.g., older age, education level, diabetes, and dyslipidemia) and other specific factors (e.g., dialysis modality, anemia, vitamin D) [16, 17]. It is imperative that the risk factors and prompt treatment of CI in the CKD population should be emphasized.

Thus far, studies regarding the prevalence of CI in CKD patients are limited and with inconsistent conclusions. Our study aimed to estimate the overall prevalence of CI in CKD patients not on dialysis, and receiving dialysis or kidney transplantation. Furthermore, the specific risk factors for CI were also explored.

Materials and methods

Protocol and registration

The protocol for this systemic review and meta-analysis was registered on PROSPERO (CRD42023412864). The reporting was done according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) Protocols guidelines [18].

Search strategy and selection criteria

A search was conducted via PubMed, Embase, and Web of Science for relevant articles. The search was conducted from January 1, 2000 to December 1, 2023 with the Medical Subject Headings terms ‘chronic kidney failure’, ‘dialysis’, and ‘cognitive dysfunction’. We also used the free terms ‘chronic kidney disease’, ‘chronic kidney insufficiency’, ‘hemodialysis’, ‘cognitive impairment’, and ‘cognitive defect’. The search strategy was adjusted based on the compatibility of each database and shown in S1 Checklist. Additionally, the reference lists of the included studies were reviewed to identify other relevant studies.

Two investigators independently selected relevant studies based on the following inclusion criteria: (1) studies specified the primary data on the prevalence of CI in CKD patients; (2) study patients aged 18 years and above; (3) study patients with CKD or undergoing any kidney replacement therapy (HD, PD, and kidney transplant); (3) observational studies, including cross-sectional studies and cohort studies; and (4) included at least 50 participants. Articles without prevalence data, without the diagnosis criteria of CI, not written in English, or studies in the form of commentaries, editorials, reviews, or case reports were excluded. For overlapping data of the same cohorts, we included only the most comprehensive data.

Data extraction and risk of bias assessment

Two authors (J.L.Z. and L.Y.W.) independently selected the articles by screening the title, abstract and full text according to eligibility criteria. The inconsistencies were resolved by a third author (A.H.Z.). Data extraction of eligible articles, including author, year of publication, study design, sample size, baseline characteristics of the patients, and measurement tools for CI, was independently carried out by two reviewers (J.L.Z. and L.Y.W.). The risk of bias was assessed using the Newcastle–Ottawa Scale (NOS) [19]. A total of <3 points was considered low quality, 4–6 points was considered moderate quality, and 7–10 points was considered high quality.

Statistical analysis

Meta-analysis was conducted in Stata version 15 statistical software. Analyses of pooled estimates of the prevalence of CI in CKD patients were presented as percentages with a 95% confidence interval (95% CI) using forest plots. Heterogeneity was assessed for the statistical significance using I2 [20]. A random-effects model was employed when I2 >50%. Subgroup analysis was performed stratified by publication year, dialysis modality, regions, diagnostic instruments, and degree of CI to further investigate the heterogeneity across studies. Besides, the publication bias was evaluated by Egger’s regression test. In terms of associated factors for CI, the adjusted odds ratio (OR) with a corresponding 95% CI was calculated. A P value < 0.05 was considered to be statistically significant.

Results

Characteristics of the included studies

A total of 4773 publications were identified at the three electronic databases in the initial search, and 50 studies [12–15, 21–65] were included according to the selection criteria. Fig 1 represented the flowchart of the selection of studies for our systematic review and meta-analysis. S1 Table summarized the characteristics of the selected articles. In total, 25,289 CKD patients were included across 50 studies. Among these studies, 16 studies were conducted in America, 16 were from Asia, 3 were across Africa, 14 were conducted in Europe, and 1 was from Australia. 12 studies involved CKD patients without dialysis, 17 studies involved patients on HD, 10 studies involved patients on PD, and 6 studies involved patients with kidney transplant. Multiple instruments have been used to evaluate cognitive function. 15 studies used Montreal Cognitive Assessment (MoCA), 25 studies used Mini-mental State Examination (MMSE), and 2 studies used Adden brooke’s Cognitive Examination III (ACE III).

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Fig 1. PRISMA flow diagram.

https://doi.org/10.1371/journal.pone.0304762.g001

Prevalence of CI in patients with CKD

The results of the primary analyses were presented in Fig 2. The pooled prevalence of CI among CKD patients was estimated to be 40% (95% CI, 33–46) with a significant heterogeneity as evidenced by I2 statistic (I2 = 99%; p < 0.0001). Hence, a random effect model was employed considering the significant heterogeneity among the studies. Egger’s test provided evidence of publication bias in the overall meta‐analysis (P = 0.002).

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Fig 2. Forest plot of the pooled prevalence of cognitive impairment among CKD patients.

NOTE: Weights are from random-effects model.

https://doi.org/10.1371/journal.pone.0304762.g002

Subgroup analysis

Table 1 summarized the subgroup analyses determining the pooled prevalence of CI in CKD patients. To pinpoint the source of heterogeneity, subgroup analyses were performed stratified by the study area, year of publication, type of cohorts, assessment tools, cognitive subdomains, and degree of CI. The forest plots were shown in S1-S6 Figs in S1 File. The prevalence of CI was 37% in USA, 58% in Africa, 44% in Asia, 34% in Europe, and 14% in Australia, respectively. Based on the patients’ type, the highest prevalence was identified in patients with HD (53%), followed by patients with PD (39%), CKD patients without dialysis (32%) and post-kidney transplanted patients (26%). Furthermore, the pooled prevalence of CI was 57% assessed by MoCA, 27% assessed by MMSE, and 40% assessed by ACE III. Among the various cognitive subdomains, 29% had impaired attention; 28% had impaired executive function; 18% had impaired delayed memory, and 16% had impaired language. According to the prespecified criteria from original studies, 35% of the patients had mild CI, and 33% had moderate-severe CI. In addition, we estimated the prevalence of CI according to year of publication. The prevalence of CI was higher after 2015 than before 2015 (42%, 95% CI 35%-50%, and 31%, 95% CI 23%-38%).

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Table 1. The pooled prevalence of cognitive impairment in CKD patients by subgroup analysis.

https://doi.org/10.1371/journal.pone.0304762.t001

Factors associated with CI among CKD patients

Six studies evaluated the association between the older age and the presence of CI among CKD patients. The pooled OR showed that older CKD patients were more likely to have CI (OR = 1.07, 95% CI:1.04–1.11). The analysis of four studies showed that prevalence of CI was comparable between male and female CKD patients (OR = 0.88, 95% CI:0.67–1.16). CKD patients with diabetes or hypertension were likely to have a significantly higher rate of CI (OR = 1.35, 95% CI:0.99–1.86; OR = 1.88, 95% CI:1.1–3.22). However, the status of smoke or drink did not affect the prevalence of CI in CKD patients (OR = 0.69, 95% CI:0.44–1.08; OR = 0.79, 95% CI:0.44–1.4) (S7 Fig in S1 File).

Discussion

To our knowledge, this is the first systematic review and meta-analysis to assess the prevalence of CI in patients with CKD stage 1 to 5 and the population on HD, PD or kidney transplantation. We carried out a comprehensive systematic review and meta-analysis of 50 studies that included 25,289 CKD patients to investigate the prevalence of CI. The overall prevalence of CI was 40% in CKD patients. We observed high prevalence of CI (39% and 53%) in patients undergoing PD and HD in comparison to patients after kidney transplantation (26%). Overall, these data highlighted the burden of CI, and the importance of early detection and treatment for CI in CKD patients should be emphasized.

CKD is a growing health problem worldwide [66]. A decrease in cognitive function might be correlated with the severity of renal failure [67]. A cross-sectional study reported that each 10-mL/min/1.73 m2 decrease in the estimated GFR less than 60 mL/min/1.73 m2 was associated with an 11% increase in the prevalence of CI [68]. The pathophysiology of CI in CKD patients is multifactorial and undefined. Traditional cardiovascular risk factors and various kidney-disease related factors, including uremic toxins, dialysis modality, complications of dialysis, and anemia, have been identified [6]. The prevalence of CI varied widely in patients with CKD, ranging from 5% to 87% [35, 37]. On the basis of our meta-analysis, we reported the disparities in the prevalence of CI in CKD patients from different ethnic groups. The wide discrepancies in the burden of CI among CKD patients might be due to the different sample sizes, high heterogeneity of the study population characteristics, differences in the socioeconomic status, stage of CKD, access to diagnostic facilities and quality of healthcare services. Higher Medicare total annual cost of care significantly correlated with dementia [69]. Additionally, lifestyle, containing diets and physical activity, varied between countries and may potentially impact the prevalence of CI. Mediterranean diet and exercise could significantly lower the incident risk of cognitive disorders [70–72]. However, some other regions of the developing world were not represented in this analysis, probably leading to a variation. Additional studies exploring the prevalence of CI in CKD patients from developing countries are needed. An increasing trend in the global burden of CI in CKD patients was reported from the years below 2015 to the years over 2015. The differences might be explained by other comorbid conditions, unhealthy lifestyles, awareness of healthcare utilization and poor-quality healthcare services [73].

The effect of dialysis modalities on the cognitive functions was debated. The 5-year cumulative risk of dementia in PD patients was lower than that in HD patients in a large retrospective study [74]. In our study, we also found that PD patients seemed to have a significantly lower prevalence of CI than HD patients. Various comorbidities, such as diabetes, hypertension and dyslipidemia, could be common in end-stage renal disease patients with HD, and these comorbidities might increase the risk of CI [75]. Evidence underscored that CI was considerably prevalent among individuals with hypertension [76] and diabetes [77]. The intervention to maintain blood pressure and serum glucose might benefit for cognition [78–80]. For example, dapagliflozin and vildagliptin could exert beneficial effects on neuroprotection [81]. Angiotensin-converting enzyme inhibitor and/or angiotensin receptor blocker could decrease odds of CI through ameliorating albuminuria [82]. In our meta-analysis, we also found that diabetes and hypertension were independent risk factors for CI in CKD patients. Besides, the residual kidney function might be better preserved in PD patients than in HD patients [83]. Patients with HD are more likely to suffer from a large fluid and osmolar fluctuation than patients with PD, probably leading to a decreased cerebral perfusion, and cerebral ischemia. On the other hand, the choice of dialysis method might be affected by autonomy, economic status, the level of education, and preferences. Patients likely need a better baseline cognition status to complete PD training programs. Consequently, the choice of renal replacement therapy in the clinical should be comprehensively considered. Evidence showed that post-transplanted patients performed better on general cognitive status, information and motor speed, spatial reasoning, and verbal memory when compared with dialysis-dependent patients [84]. The prevalence of CI in post-transplanted patients was also lower than that in HD and PD patients in this study. The risk of CI might decrease with a better renal function. Meanwhile, the neurotoxicity of calcineurin inhibitor after transplantation could not be ignored, either [85].

A high prevalence of white matter disease was shown in PD patients [86], accompanied by a decline in cognitive function [87]. A study including 51 PD patients showed that the prevalence of CI was approximately 75%, which was higher than that of our study. However, the number of patients included was small, which might lead to uncertainty. Among those patients, approximately one-third had moderate impairment, and one-third had severe impairment [88]. According to the degree of CI, our sub-analysis results showed that the prevalence of mild CI and major CI was 35% and 33% in CKD patients, respectively. Patients with mild CI even showed declines in the ability to perform instrumental activities of daily living, such as telephone calls, preparing hot meals, remembering to take medication, remembering appointments, talking about recent events, and performing hobbies [89]. A further comprehensive evaluation should be taken into consideration as early as possible in an individual with mild or moderate CI.

Clinical screening for CI relies on the use of cognitive tests. Regarding different diagnostic criteria, our meta-analysis illustrated that the prevalence of CI in CKD patients was highest when assessed by MoCA, followed by MMSE and ACE III. A study presented that the MoCA had greater sensitivity and specificity for detecting mild CI than does the MMSE [90]. Another small study of prevalent HD patients also revealed that the MoCA performed better than MMSE on neurocognitive tests [91, 92]. The pattern of CI in CKD is unclear. A previous meta-analysis showed that CKD patients performed worse on both attention, language, executive function, and memory [5]. However, cognitive performance in patients with dialysis and kidney transplant was not involved, and the robust prevalence data was absent. Subgroup analysis of this study indicated that the prevalence of attention dysfunction (29%) and executive dysfunction (28%) was higher than memory dysfunction (18%) and language dysfunction (16%). CI is common in patients treated with HD, particularly in the domains of attention and executive function [93]. The impairment of cognitive pattern seems to be different in PD patients, with more memory impairment [88]. Future research may propose more representative cognitive tests for multiple cognitive patterns in CKD patients.

Our current meta-analysis included a larger number of studies and more convincing articles to determine the prevalence of CI in CKD patients, likely leading to a more reliable conclusion. Our results recommended physicians to early diagnostics and intervene the progression of CI. Our study had several limitations. First, the heterogeneity was high in the meta-analysis of the prevalence of CI. Although several subgroup analyses were performed, the source of heterogeneity was not well defined. Second, the risk factors for CI extracted from the original studies were limited. Further studies are needed to determine the associated factors on CI in CKD patients, such as race, depression, nutritional patterns, and other dialysis-related factors. Additionally, the reports on efficacy and safety of antidementia drugs for CKD patients was too few to include in this meta-analysis. Third, the definition of CI was inconclusive across each individual study, which may lead to a bias. Fourth, the articles included were restricted only to those written in the English language.

Conclusion

CI is highly prevalent in CKD patients worldwide, especially in USA, Africa and Asia. Our findings highlighted that the estimated prevalence of CI in CKD patients varied among different subdomains and degrees of CI. A screening for CI is urgently needed in CKD patients, particularly in patients undergoing HD and PD.

References

  1. 1. Ortiz A. RICORS2040: the need for collaborative research in chronic kidney disease. Clin Kidney J. 2022;15(3):372–87. pmid:35211298
  2. 2. Kalantar-Zadeh K, Jafar TH, Nitsch D, et al. Chronic kidney disease. Lancet. 2021;398(10302):786–802. pmid:34175022
  3. 3. Hill NR, Fatoba ST, Oke JL, et al. Global Prevalence of Chronic Kidney Disease ‐ A Systematic Review and Meta-Analysis. PLoS One. 2016;11(7):e0158765. pmid:27383068
  4. 4. Yaffe K, Ackerson L, Kurella Tamura M, et al. Chronic kidney disease and cognitive function in older adults: findings from the chronic renal insufficiency cohort cognitive study. J Am Geriatr Soc. 2010;58(2):338–45. pmid:20374407
  5. 5. Berger I, Wu S, Masson P, et al. Cognition in chronic kidney disease: a systematic review and meta-analysis. BMC Med. 2016;14(1):206. pmid:27964726
  6. 6. Drew DA, Weiner DE, Sarnak MJ. Cognitive Impairment in CKD: Pathophysiology, Management, and Prevention. Am J Kidney Dis. 2019;74(6):782–90. pmid:31378643
  7. 7. Tuladhar AM, van Norden AG, de Laat KF, et al. White matter integrity in small vessel disease is related to cognition. Neuroimage Clin. 2015;7:518–24. pmid:25737960
  8. 8. Sedaghat S, Cremers LG, de Groot M, et al. Kidney function and microstructural integrity of brain white matter. Neurology. 2015;85(2):154–61. pmid:26085601
  9. 9. Song YH, Cai GY, Xiao YF, et al. Risk factors for mortality in elderly haemodialysis patients: a systematic review and meta-analysis. BMC Nephrol. 2020;21(1):377. pmid:32867718
  10. 10. Kurella M, Chertow GM, Luan J, et al. Cognitive impairment in chronic kidney disease. J Am Geriatr Soc. 2004;52(11):1863–9. pmid:15507063
  11. 11. Murray AM, Tupper DE, Knopman DS, et al. Cognitive impairment in hemodialysis patients is common. Neurology. 2006;67(2):216–23. pmid:16864811
  12. 12. Yi C, Zhang W, Ye H, et al. Association of brachial-ankle pulse wave velocity with cognitive impairment in peritoneal dialysis patients. Ren Fail. 2021;43(1):934–41. pmid:34120562
  13. 13. Miller LM, Rifkin D, Lee AK, et al. Association of Urine Biomarkers of Kidney Tubule Injury and Dysfunction With Frailty Index and Cognitive Function in Persons With CKD in SPRINT. Am J Kidney Dis. 2021;78(4):530–40.e1. pmid:33647393
  14. 14. Seidel UK, Gronewold J, Volsek M, et al. Physical, cognitive and emotional factors contributing to quality of life, functional health and participation in community dwelling in chronic kidney disease. PLoS One. 2014;9(3):e91176. pmid:24614180
  15. 15. Egbi OG, Ogunrin O, Oviasu E. Prevalence and determinants of cognitive impairment in patients with chronic kidney disease: a cross-sectional study in Benin City, Nigeria. Ann Afr Med. 2015;14(2):75–81. pmid:25693814
  16. 16. Kurella Tamura M, Vittinghoff E, Yang J, et al. Anemia and risk for cognitive decline in chronic kidney disease. BMC Nephrol. 2016;17:13. pmid:26823182
  17. 17. Cheng Z, Lin J, Qian Q. Role of Vitamin D in Cognitive Function in Chronic Kidney Disease. Nutrients. 2016;8(5). pmid:27187460
  18. 18. Moher D, Liberati A, Tetzlaff J, et al. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009;6(7):e1000097. pmid:19621072
  19. 19. Modesti PA, Reboldi G, Cappuccio FP, et al. Panethnic Differences in Blood Pressure in Europe: A Systematic Review and Meta-Analysis. PLoS One. 2016;11(1):e0147601. pmid:26808317
  20. 20. Higgins JP. Commentary: Heterogeneity in meta-analysis should be expected and appropriately quantified. Int J Epidemiol. 2008;37(5):1158–60. pmid:18832388
  21. 21. Ookawara S, Ito K, Sasabuchi Y, et al. Cerebral oxygenation and body mass index association with cognitive function in chronic kidney disease patients without dialysis: a longitudinal study. Sci Rep. 2022;12(1):10809. pmid:35752646
  22. 22. Yen FS, Wang SI, Lin SY, et al. The Impact of Alcohol Consumption on Cognitive Impairment in Patients With Diabetes, Hypertension, or Chronic Kidney Disease. Front Med (Lausanne). 2022;9:861145. pmid:35721095
  23. 23. Angermann S, Günthner R, Hanssen H, et al. Cognitive impairment and microvascular function in end-stage renal disease. Int J Methods Psychiatr Res. 2022;31(2):e1909. pmid:35290686
  24. 24. Paterson EN, Maxwell AP, Kee F, et al. Association of renal impairment with cognitive dysfunction in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA). Nephrol Dial Transplant. 2021;36(8):1492–9. pmid:34038557
  25. 25. Tollitt J, Odudu A, Montaldi D, et al. Cognitive impairment in patients with moderate to severe chronic kidney disease: the Salford kidney cohort study. Clin Kidney J. 2021;14(6):1639–48. pmid:34084459
  26. 26. Murali KM, Mullan J, Roodenrys S, et al. Changes in measures of cognitive function in patients with end-stage kidney disease on dialysis and the effect of dialysis vintage: A longitudinal cohort study. PLoS One. 2021;16(5):e0252237. pmid:34033657
  27. 27. Huang X, Yi C, Wu M, et al. Risk Factors and Clinical Outcomes of Cognitive Impairment in Diabetic Patients Undergoing Peritoneal Dialysis. Kidney Blood Press Res. 2021;46(5):531–40. pmid:34229326
  28. 28. Luo Y, Murray AM, Guo YD, et al. Cognitive impairment and associated risk factors in older adult hemodialysis patients: a cross-sectional survey. Sci Rep. 2020;10(1):12542. pmid:32719428
  29. 29. Drew DA, Tighiouart H, Rollins J, et al. Evaluation of Screening Tests for Cognitive Impairment in Patients Receiving Maintenance Hemodialysis. J Am Soc Nephrol. 2020;31(4):855–64. pmid:32132197
  30. 30. Cho NJ, Park S, Lee EY, et al. Association of Intracranial Artery Calcification with Cognitive Impairment in Hemodialysis Patients. Med Sci Monit. 2019;25:5036–43. pmid:31280282
  31. 31. Zhao Y, Zhang Y, Yang Z, et al. Sleep Disorders and Cognitive Impairment in Peritoneal Dialysis: A Multicenter Prospective Cohort Study. Kidney Blood Press Res. 2019;44(5):1115–27. pmid:31537006
  32. 32. Findlay MD, Dawson J, Dickie DA, et al. Investigating the Relationship between Cerebral Blood Flow and Cognitive Function in Hemodialysis Patients. J Am Soc Nephrol. 2019;30(1):147–58. pmid:30530658
  33. 33. Hobson P, Lewis A, Nair H, et al. 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. BMJ Open. 2018;8(12):e023520. pmid:30518585
  34. 34. Harhay MN, Xie D, Zhang X, et al. Cognitive Impairment in Non-Dialysis-Dependent CKD and the Transition to Dialysis: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study. Am J Kidney Dis. 2018;72(4):499–508. pmid:29728316
  35. 35. Neumann D, Mau W, Wienke A, et al. Peritoneal dialysis is associated with better cognitive function than hemodialysis over a one-year course. Kidney Int. 2018;93(2):430–8. pmid:29042081
  36. 36. Burns CM, Knopman DS, Tupper DE, et al. Prevalence and Risk of Severe Cognitive Impairment in Advanced Chronic Kidney Disease. J Gerontol A Biol Sci Med Sci. 2018;73(3):393–9. pmid:29244090
  37. 37. Zheng K, Wang H, Hou B, et al. Malnutrition-inflammation is a risk factor for cerebral small vessel diseases and cognitive decline in peritoneal dialysis patients: a cross-sectional observational study. BMC Nephrol. 2017;18(1):366. pmid:29262796
  38. 38. Liao JL, Xiong ZY, Yang ZK, et al. An association of cognitive impairment with diabetes and retinopathy in end stage renal disease patients under peritoneal dialysis. PLoS One. 2017;12(8):e0183965. pmid:28859133
  39. 39. Pi HC, Xu YF, Xu R, et al. Cognitive Impairment and Structural Neuroimaging Abnormalities Among Patients with Chronic Kidney Disease. Kidney Blood Press Res. 2016;41(6):986–96. pmid:27988515
  40. 40. McAdams-DeMarco MA, Tan J, Salter ML, et al. Frailty and Cognitive Function in Incident Hemodialysis Patients. Clin J Am Soc Nephrol. 2015;10(12):2181–9. pmid:26573615
  41. 41. Liu GL, Pi HC, Hao L, et al. Vitamin D Status Is an Independent Risk Factor for Global Cognitive Impairment in Peritoneal Dialysis Patients. PLoS One. 2015;10(12):e0143782. pmid:26630385
  42. 42. Xu R, Pi HC, Xiong ZY, et al. Hyponatremia and Cognitive Impairment in Patients Treated with Peritoneal Dialysis. Clin J Am Soc Nephrol. 2015;10(10):1806–13. pmid:26231192
  43. 43. Antunes JP, Bulhões C, Fonte P, et al. Renal function and cognitive dysfunction: cross-sectional study of users enrolled at Ponte Family Health Unit. J Bras Nefrol. 2015;37(1):79–90. pmid:25923754
  44. 44. Jung S, Lee YK, Choi SR, et al. Relationship between cognitive impairment and depression in dialysis patients. Yonsei Med J. 2013;54(6):1447–53. pmid:24142650
  45. 45. Williams UE, Owolabi MO, Ogunniyi A, et al. Prevalence and pattern of neurocognitive impairment in nigerians with stages 3 to 5 chronic kidney disease. ISRN Neurol. 2013;2013:374890. pmid:23864958
  46. 46. Yaffe K, Ackerson L, Hoang TD, et al. Retinopathy and cognitive impairment in adults with CKD. Am J Kidney Dis. 2013;61(2):219–27. pmid:23206534
  47. 47. Post JB, Morin KG, Sano M, et al. Increased presence of cognitive impairment in hemodialysis patients in the absence of neurological events. Am J Nephrol. 2012;35(2):120–6. pmid:22212437
  48. 48. Kurella Tamura M, Larive B, Unruh ML, et al. Prevalence and correlates of cognitive impairment in hemodialysis patients: the Frequent Hemodialysis Network trials. Clin J Am Soc Nephrol. 2010;5(8):1429–38. pmid:20576825
  49. 49. Post JB, Jegede AB, Morin K, et al. Cognitive profile of chronic kidney disease and hemodialysis patients without dementia. Nephron Clin Pract. 2010;116(3):c247–55. pmid:20606486
  50. 50. Sarnak MJ, Tighiouart H, Scott TM, et al. Frequency of and risk factors for poor cognitive performance in hemodialysis patients. Neurology. 2013;80(5):471–80. pmid:23303848
  51. 51. Viana FS, Boechat YEM, Lugon JR, et al. Differences in quality of life and cognition between the elderly and the very elderly hemodialysis patients. J Bras Nefrol. 2019;41(3):375–83. pmid:30897190
  52. 52. Gela YY, Getu AA, Adane A, et al. Cognitive Impairment and Associated Factors Among Chronic Kidney Disease Patients: A Comparative Cross-Sectional Study. Neuropsychiatr Dis Treat. 2021;17:1483–92. pmid:34040375
  53. 53. Tian R, Guo Y, Ye P, et al. The validation of the Beijing version of the Montreal Cognitive Assessment in Chinese patients undergoing hemodialysis. PLoS One. 2020;15(1):e0227073. pmid:31917792
  54. 54. Joseph SJ, Bhandari SS, Dutta S. Cognitive Impairment and its Correlates in Chronic Kidney Disease Patients Undergoing Haemodialysis. J Evol Med Dent Sci. 2019;8(36):2818–22. pmid:31632935
  55. 55. Pei X, Lai S, He X, et al. Mild cognitive impairment in maintenance hemodialysis patients: a cross-sectional survey and cohort study. Clin Interv Aging. 2019;14:27–32. pmid:30587951
  56. 56. Zubair UB, Butt B. Association Of Quality Of Sleep With Cognitive Decline Among The Patients Of Chronic Kidney Disease Undergoing Haemodialysis. J Ayub Med Coll Abbottabad. 2017;29(4):619–22. pmid:29330990
  57. 57. Kurella Tamura M, Yaffe K, Hsu CY, et al. Cognitive Impairment and Progression of CKD. Am J Kidney Dis. 2016;68(1):77–83. pmid:26972681
  58. 58. Rodríguez-Angarita CE, Sanabria-Arenas RM, Vargas-Jaramillo JD, et al. Cognitive impairment and depression in a population of patients with chronic kidney disease in Colombia: a prevalence study. Can J Kidney Health Dis. 2016;3:26. pmid:27168941
  59. 59. Shea YF, Lam MF, Lee MS, et al. Prevalence of Cognitive Impairment Among Peritoneal Dialysis Patients, Impact on Peritonitis and Role of Assisted Dialysis. Perit Dial Int. 2016;36(3):284–90. pmid:26634566
  60. 60. Golenia A, Olejnik P, Żołek N, et al. Cognitive Impairment and Anxiety Are Prevalent in Kidney Transplant Recipients. Kidney Blood Press Res. 2023;48(1):587–95. pmid:37619550
  61. 61. Chu NM, Chen X, Gross AL, et al. Cognitive impairment burden in older and younger adults across the kidney transplant care continuum. Clin Transplant. 2021;35(10):e14425. pmid:34272777
  62. 62. Pépin M, Levassort H, Boucquemont J, et al. Cognitive performance is associated with glomerular filtration rate in patients with chronic kidney disease: results from the CKD-REIN cohort. J Neurol Neurosurg Psychiatry. 2023;94(6):457–66. pmid:36693722
  63. 63. Nöhre M, Bauer-Hohmann M, Klewitz F, et al. Prevalence and Correlates of Cognitive Impairment in Kidney Transplant Patients Using the DemTect-Results of a KTx360 Substudy. Front Psychiatry. 2019;10:791. pmid:31736808
  64. 64. Gupta A, Mahnken JD, Johnson DK, et al. Prevalence and correlates of cognitive impairment in kidney transplant recipients. BMC Nephrol. 2017;18(1):158. pmid:28499360
  65. 65. Zachciał J, Uchmanowicz I, Czapla M, et al. The Association between Psychosocial and Age-Related Factors with Adherence to Immunosuppressive Therapies after Renal Transplantation. J Clin Med. 2022;11(9). pmid:35566514
  66. 66. Kovesdy CP. Epidemiology of chronic kidney disease: an update 2022. Kidney Int Suppl (2011). 2022;12(1):7–11. pmid:35529086
  67. 67. Kurella Tamura M, Yaffe K. Dementia and cognitive impairment in ESRD: diagnostic and therapeutic strategies. Kidney Int. 2011;79(1):14–22. pmid:20861818
  68. 68. Kurella Tamura M, Wadley V, Yaffe K, et al. Kidney function and cognitive impairment in US adults: the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study. Am J Kidney Dis. 2008;52(2):227–34. pmid:18585836
  69. 69. Johnston KJ, Wen H, Hockenberry JM, et al. Association Between Patient Cognitive and Functional Status and Medicare Total Annual Cost of Care: Implications for Value-Based Payment. JAMA Intern Med. 2018;178(11):1489–97. pmid:30242381
  70. 70. Wu L, Sun D. Adherence to Mediterranean diet and risk of developing cognitive disorders: An updated systematic review and meta-analysis of prospective cohort studies. Sci Rep. 2017;7:41317. pmid:28112268
  71. 71. Singh B, Parsaik AK, Mielke MM, et al. Association of mediterranean diet with mild cognitive impairment and Alzheimer’s disease: a systematic review and meta-analysis. J Alzheimers Dis. 2014;39(2):271–82. pmid:24164735
  72. 72. Otobe Y, Yamada M, Hiraki K, et al. Physical Exercise Improves Cognitive Function in Older Adults with Stage 3–4 Chronic Kidney Disease: A Randomized Controlled Trial. Am J Nephrol. 2021;52(12):929–39. pmid:34847564
  73. 73. Vart P, Gansevoort RT, Crews DC, et al. Mediators of the association between low socioeconomic status and chronic kidney disease in the United States. Am J Epidemiol. 2015;181(6):385–96. pmid:25731886
  74. 74. Wolfgram DF, Szabo A, Murray AM, et al. Risk of dementia in peritoneal dialysis patients compared with hemodialysis patients. Perit Dial Int. 2015;35(2):189–98. pmid:25742686
  75. 75. Biessels GJ, Staekenborg S, Brunner E, et al. Risk of dementia in diabetes mellitus: a systematic review. Lancet Neurol. 2006;5(1):64–74. pmid:16361024
  76. 76. Pallangyo P, Mkojera ZS, Komba M, et al. Burden and correlates of cognitive impairment among hypertensive patients in Tanzania: a cross-sectional study. BMC Neurol. 2021;21(1):433. pmid:34749692
  77. 77. Zhao Q, Zhang Y, Liao X, et al. Executive Function and Diabetes: A Clinical Neuropsychology Perspective. Front Psychol. 2020;11:2112. pmid:32973635
  78. 78. Awad N, Gagnon M, Messier C. The relationship between impaired glucose tolerance, type 2 diabetes, and cognitive function. J Clin Exp Neuropsychol. 2004;26(8):1044–80. pmid:15590460
  79. 79. Flythe JE, Xue H, Lynch KE, et al. Association of mortality risk with various definitions of intradialytic hypotension. J Am Soc Nephrol. 2015;26(3):724–34. pmid:25270068
  80. 80. Shurraw S, Majumdar SR, Thadhani R, et al. Glycemic control and the risk of death in 1,484 patients receiving maintenance hemodialysis. Am J Kidney Dis. 2010;55(5):875–84. pmid:20346561
  81. 81. Sa-Nguanmoo P, Tanajak P, Kerdphoo S, et al. SGLT2-inhibitor and DPP-4 inhibitor improve brain function via attenuating mitochondrial dysfunction, insulin resistance, inflammation, and apoptosis in HFD-induced obese rats. Toxicol Appl Pharmacol. 2017;333:43–50. pmid:28807765
  82. 82. Barzilay JI, Gao P, O’Donnell M, et al. Albuminuria and decline in cognitive function: The ONTARGET/TRANSCEND studies. Arch Intern Med. 2011;171(2):142–50. pmid:21263104
  83. 83. Clark WR, Dehghani NL, Narsimhan V, et al. Uremic Toxins and their Relation to Dialysis Efficacy. Blood Purif. 2019;48(4):299–314. pmid:31563911
  84. 84. Joshee P, Wood AG, Wood ER, et al. Meta-analysis of cognitive functioning in patients following kidney transplantation. Nephrol Dial Transplant. 2018;33(7):1268–77. pmid:28992229
  85. 85. Pflugrad H, Nösel P, Ding X, et al. Brain function and metabolism in patients with long-term tacrolimus therapy after kidney transplantation in comparison to patients after liver transplantation. PLoS One. 2020;15(3):e0229759. pmid:32155172
  86. 86. Kim CD, Lee HJ, Kim DJ, et al. High prevalence of leukoaraiosis in cerebral magnetic resonance images of patients on peritoneal dialysis. Am J Kidney Dis. 2007;50(1):98–107. pmid:17591529
  87. 87. Inzitari D, Pracucci G, Poggesi A, et al. Changes in white matter as determinant of global functional decline in older independent outpatients: three year follow-up of LADIS (leukoaraiosis and disability) study cohort. Bmj. 2009;339:b2477. pmid:19581317
  88. 88. Kalirao P, Pederson S, Foley RN, et al. Cognitive impairment in peritoneal dialysis patients. Am J Kidney Dis. 2011;57(4):612–20. pmid:21295896
  89. 89. Ahn IS, Kim JH, Kim S, et al. Impairment of instrumental activities of daily living in patients with mild cognitive impairment. Psychiatry Investig. 2009;6(3):180–4. pmid:20046393
  90. 90. Nasreddine ZS, Phillips NA, Bédirian V, et al. The Montreal Cognitive Assessment, MoCA: a brief screening tool for mild cognitive impairment. J Am Geriatr Soc. 2005;53(4):695–9. pmid:15817019
  91. 91. Tiffin-Richards FE, Costa AS, Holschbach B, et al. The Montreal Cognitive Assessment (MoCA) ‐ a sensitive screening instrument for detecting cognitive impairment in chronic hemodialysis patients. PLoS One. 2014;9(10):e106700. pmid:25347578
  92. 92. Lee SH, Cho A, Min YK, et al. Comparison of the montreal cognitive assessment and the mini-mental state examination as screening tests in hemodialysis patients without symptoms. Ren Fail. 2018;40(1):323–30. pmid:29633885
  93. 93. O’Lone E, Connors M, Masson P, et al. Cognition in People With End-Stage Kidney Disease Treated With Hemodialysis: A Systematic Review and Meta-analysis. Am J Kidney Dis. 2016;67(6):925–35.