Dementia prevalence is alarmingly high in haemodialysis patients, reaching as much as 30%, yet it often goes unrecognized and underdiagnosed.1,2 “In patients with End-Stage Renal Disease (ESRD), cognitive function is closely linked to the severity of renal disease and the associated risk of dementia. This heightened risk and prevalence of dementia in ESRD patients, particularly those undergoing haemodialysis (HD), are often preceded by mild cognitive impairment (MCI), a transitional stage between normal age-related cognitive changes and dementia.3,4 

Patients with chronic kidney disease (CKD) on haemodialysis exhibit a notably high prevalence of MCI even when their global cognitive function appears intact. In the early stages of CKD, executive function and attention are the cognitive domains most commonly affected. However, as the disease progresses to ESRD requiring haemodialysis, cognitive impairment becomes more severe and widespread, encompassing multiple domains. This suggests a gradation of cognitive decline that correlates with the severity of kidney dysfunction.”5,6 

Notably, MCI is more prevalent among HD patients compared to those with mild to moderate CKD, with cognitive deficits occurring more frequently and affecting a broader range of cognitive domains. Haemodialysis-related factors, such as hemodynamic instability, toxin accumulation, and inflammation, may contribute to this decline. Despite its significant impact, cognitive impairment in HD patients remains poorly understood and underexplored. 

Understanding the scope and mechanisms of cognitive dysfunction in HD patients is crucial, as it may inform early interventions to slow progression, optimize dialysis practices, and improve overall quality of life. This underscores the need for focused studies to substantiate the extent of cognitive impairment in haemodialysis patients and identify modifiable factors contributing to their vulnerability. Present study aimed to determine presence of cognitive deficits in patients with chronic kidney disease undergoing haemodialysis.

This cross-sectional study was conducted among 64 patients who are attending Medicine OPD and admitted with a history of clinical findings and investigation findings suggestive of chronic kidney disease and undergoing haemodialysis where patients are screening for cognitive impairment using Montreal Cognitive Assessment (MOCA) in BLDE deemed to be university Shri B M Patil Medical College, Hospital and Research Centre, Vijayapura. Patients history of dementia, stroke and neurodegenerative disorders were excluded.

The data was collected according to proforma in terms of detailed history, clinical examination and necessary investigations of the patient who fulfil the inclusion criteria and exclusion criteria are taken up for study after obtaining consent. Patients were screened with MOCA to assess the cognitive disorder and grouped as patients with hemodialysis and patients without hemodialysis.

Statistical analysis: Obtained data were recorded into a Microsoft Excel sheet and analyzed statistically using statistical package for social science (SPSS Version 20) Results were expressed as Mean (Median) ±SD, counts and percentages and drawn in the form of tables, bar diagrams, pie chart and figures. The continuous variables between two groups was analysed using the Independent t-test. The Chi-square test was used to compare categorical variables, for all statistical purpose a p-value of <0.05 was considered statistical significance.

Present study included total of 64 patients with mean age of 52.67±14.2yrs. Among them 37.5% were female and 62.5% were male with male preponderance in study.

Smoking is present in 4.7% and 32.8% alcoholic. Hypertension is present in 50% and diabetes in 31.3% of cases. The cognitive impairment is present in 40.6% of the patients on dialysis.

There is significant higher duration of hemodialysis in patients with cognitive impairment (8.6months) compared to patients without cognitive impairment (3.5months).(p<0.05) There is significant longer duration of CKD in patients with cognitive impairment (2.5yrs) compared to patients without cognitive impairment (1.6yrs).(p<0.05).

Chronic Kidney Disease (CKD) is a growing global health concern, with a significant number of patients progressing to End-Stage Renal Disease (ESRD) requiring hemodialysis (HD) for survival.^7,8 While hemodialysis effectively removes waste products and excess fluids from the blood, emerging evidence suggests that it may have detrimental effects on cognitive function. Cognitive impairment in patients undergoing hemodialysis is a significant yet often underrecognized issue, impacting memory, attention, executive function, and overall quality of life.^8–10 Given the increasing burden of cognitive impairment among hemodialysis patients, early identification and intervention are crucial. Routine cognitive assessments, optimized dialysis protocols, and targeted management strategies may help mitigate cognitive decline and improve patient outcomes. Understanding the relationship between hemodialysis and cognitive impairment is essential for developing comprehensive care plans that address both renal and neurological health in this vulnerable population.

Present study included total of 64 patients with mean age of 52.67±14.2yrs. Among them 37.5% were female and 62.5% were male with male preponderance in study. Smoking is present in 4.7% and 32.8% alcoholic. Hypertension is present in 50% and diabetes in 31.3% of cases. In similar Joseph SJ et al., documented with mean age of patients in the study was 50.32 (±12.4) years, with a mean dialysis duration of 18.8 (±15.11) months. ¹¹

The mean duration of CKD was 1.6yrs. The cognitive impairment is present in 40.6% of the patients on hemodialysis. There is significant longer duration of CKD in patients with cognitive impairment (2.5yrs) compared to patients without cognitive impairment (1.6yrs).(p<0.05) There is significant higher duration of hemodialysis in patients with cognitive impairment (8.6months) compared to patients without cognitive impairment (3.5months).(p<0.05) Similar to present study Cao T et al., documented the cognitive impairment in 49.1% of the cases on maintenance hemodialysis. The findings emphasize the need for greater attention to modifiable factors such as cardiovascular disease risks and dialysis-related variables to address cognitive impairment in this population.¹² Tian X et al., documented with findings suggest that Peritoneal Dialysis is associated with better cognitive function and reduced dementia risk, further large-scale, well-designed prospective cohort studies are needed to confirm these conclusions.¹³

Also in study by O’Lone E et al., the Hemodialysis is associated with significant cognitive deficits, particularly in orientation, attention, and executive function, warranting further research to address domain-specific impairments and their implications for patient education and chronic disease management.¹⁴ In another study by Xu H et al., found a rapid eGFR decline (>2 mL/min/1.73 m² per year) further increased dementia risk, with the association being stronger for vascular dementia than for Alzheimer’s dementia. Notably, up to 10% of dementia cases could be attributed to eGFR <60 mL/min/1.73 m², a higher proportion than that attributed to cardiovascular disease or diabetes, underscoring the significant impact of kidney function on dementia development.¹⁵ Another study by Post JB et al., documented with executive function deficits were prevalent in at least 25% of subjects in both groups, and memory impairment was observed in 13% of hemodialysis (HD) patients and 15% of chronic kidney disease (CKD) patients. Mild cognitive impairment (MCI) was found in 76% of the study population, with a significantly higher prevalence in HD patients compared to CKD patients (89% vs. 63%).⁵

Strengths: The use of the Montreal Cognitive Assessment (MOCA), a standardized cognitive assessment tool that guarantees an unbiased assessment of cognitive impairment in patients with chronic kidney disease (CKD), is one of the study's strengths. Additionally, by reducing confounding variables like dementia, stroke, and neurodegenerative diseases, the inclusion and exclusion criteria contribute to improving the reliability of the results.

Limitation: The study does have some limitations, though. The findings' applicability to the larger CKD population is limited by the small sample size of 64 patients. As a cross-sectional study, it only records information at one particular moment in time, which restricts our ability to understand how cognitive impairment changes as the illness progresses. Furthermore, because the study was carried out in a single medical facility, it might not be entirely representative of all CKD patients receiving haemodialysis, which could lead to selection bias. A more thorough knowledge of cognitive impairment in CKD patients would be possible with additional research using a larger, more varied sample and longitudinal follow-up.

These findings suggest that prolonged CKD and extended haemodialysis treatment may contribute to worsening cognitive function. Given the substantial prevalence of cognitive impairment in this population, early screening, close monitoring, and potential interventions are crucial to improving patient outcomes and quality of life. Further research is needed to explore underlying mechanisms and develop targeted strategies for cognitive preservation in hemodialysis patients.

Funding: Nil

Conflict of interest: Nil

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