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

Cognitive Impairment and Brain Atrophy in Patients with Chronic Kidney Disease

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

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.

The relationship between dietary patterns derived from inflammation and cognitive impairment in patients undergoing hemodialysis

Introduction

Dietary patterns were shown to be closely related to inflammation, which was independently associated with cognitive impairment (CI) in patients undergoing hemodialysis (HD). However, it remains unclear the influence of dietary patterns derived from inflammation on CI in this population. This study aimed to examine the association between dietary patterns derived from C-reactive protein (CRP) and interleukin-6 (IL-6) and CI in patients undergoing HD.

Methods

Dietary intake was obtained from the simplified quantitative food frequency questionnaire. Reduced rank regression (RRR) was used to extract two dietary patterns, with IL-6 and CRP as response variables. Cognitive function was examined by the Montreal Cognitive Assessment (Beijing version). Venous blood was drawn for measuring IL-6 and CRP levels. Multivariable logistic regression was used to investigate the association between dietary patterns and CI.

Results

Dietary pattern derived from IL-6 was not significantly associated with CI. The third quartile of dietary pattern, which used CRP as the response variable, significantly contributed to the increased risk of CI (AOR 8.62, 95% CI 1.47-50.67) after controlling age, sex, education level, marital status, and residential pattern (p-for-trend = 0.028). After considering hypertension and diabetes, physical activity level, anxiety and depression, smoking and drinking status, social support, energy intake, and the dietary pattern derived from IL-6 (p-for-trend = 0.026), the relationship between the dietary pattern derived from CRP and CI remained significant (AOR 14.54, 95% CI 1.40-151.13).

Conclusion

Dietary pattern associated with high CRP level, including high intake of rice, liquor, fruit, tea and coffee and low intake of dark vegetables and juice, contributed to the increased risk of CI. The association between the consumption of seafood, sweet beverages, and alcohol and CI is yet to be established. However, they may be dietary contributing factors to inflammation in patients undergoing HD.