The effects of intradialytic exercise on hemodialysis adequacy: A systematic review

Perceptions of healthcare providers on benefits, risks and barriers regarding intradialytic exercise among haemodialysis patients

PURPOSE

Clinical guidelines call for the inclusion of exercise interventions in every patient's dialysis session, but these recommendations are rarely adopted. Healthcare providers play a key role in this. Therefore, the aim of this study was to explore how healthcare providers perceive the benefits, risks and barriers of intradialytic exercise (IDE).

METHODS

We conducted 21 individual, semi-structured interviews with 11 nurses, 5 nephrologists, 3 training assistants and 2 managers from two dialysis centres in Slovakia. Verbatim transcripts of digitally recorded interviews were thematically analysed using MAXQDA®.

RESULTS

Participants reported the benefits of IDE as improvements in patients' physical and psychosocial functioning, independence and self-efficacy, clinical profile and quality of therapy. As risks of IDE, they most frequently reported exercise-related damage to vascular access, insufficient individualization of training and musculoskeletal injuries. The presence of psychological problems among patients was reported as a major barrier for initiating and maintaining patients' exercise. Other reported barriers included limitations in financial and personnel resources of haemodialysis care.

CONCLUSIONS

Safe and sustainable implementation of IDE, which might improve a patient's well-being, need to be prescribed in alignment with the patient's clinical profile, be delivered individually according to the patient's characteristics and requires adjustments in the available resources.

The impact of dialysate flow rate on haemodialysis adequacy: a systematic review and meta-analysis

Background

Patients with kidney failure treated with maintenance haemodialysis (HD) require appropriate small molecule clearance. Historically, a component of measuring 'dialysis adequacy' has been quantified using urea kinetic modelling that is dependent on the HD prescription. However, the impact of dialysate flow rate on urea clearance remains poorly described in vivo and its influence on other patient-important outcomes of adequacy is uncertain.

Methods

We searched Embase, MEDLINE and the Cochrane Library from inception until April 2022 for randomized controlled trials and observational trials comparing a higher dialysate flow rate (800 ml/min) and lower dialysate flow rate (300 ml/min) with a standard dialysis flow rate (500 ml/min) in adults (age ≥18 years) treated with maintenance HD (>90 consecutive days). We conducted a random effects meta-analysis to estimate the pooled mean difference in dialysis adequacy as measured by Kt/V or urea reduction ratio (URR).

Results

A total of 3118 studies were identified. Of those, nine met eligibility criteria and four were included in the meta-analysis. A higher dialysate flow rate (800 ml/min) increased single-pool Kt/V by 0.08 [95% confidence interval (CI) 0.05-0.10, P < .00001] and URR by 3.38 (95% CI 1.97-4.78, P < .00001) compared with a dialysate flow rate of 500 ml/min. Clinically relevant outcomes including symptoms, cognition, physical function and mortality were lacking and studies were generally at a moderate risk of bias due to issues with randomization sequence generation, allocation concealment and blinding.

Conclusion

A higher dialysate flow increased urea-based markers of dialysis adequacy. Additional high-quality research is needed to determine the clinical, economic and environmental impacts of higher dialysate flow rates.

Comparison of the efficacy of intradialytic core stabilization and aerobic exercises for hemodialysis patients: randomized controlled single-blind study

PURPOSE

This study was performed to investigate and compare the effects of intradialytic core stabilization and aerobic exercises on physical performance, fatigue, quality of life and dialysis adequacy.

MATERIALS AND METHODS

The study involved 39 individuals on hemodialysis randomized into two groups: aerobic exercise (AE, n = 20) and core stabilization (CSE, n = 19). Over 8 weeks, the AE group performed pedal ergometer exercises, while the CSE group performed 4-phase core stabilization exercises. Physical performance (five times sit to stand test, 2-min step test), quality of life (Kidney Disease Quality of Life-36; KDQOL-36), fatigue levels (Piper Fatigue Scale), and dialysis adequacy (Kt/V and URR) were assessed.

RESULTS

After training, a significant improvement was observed in the physical performance, fatigue levels, and some parameters of KDQOL-36 of the patients (p < 0.05). However, no significant changes were observed in dialysis adequacy indicators (Kt/V and URR) (p > 0.05). When the amount of development obtained in both treatment groups is compared, kidney disease burden only in the subparameter of KDQOL-36 was statistically significantly improved in the CSE group compared to the AE group (p < 0.05).

CONCLUSIONS

According to the results of the study, intradialytic core stabilization exercises appear to have similar effects to aerobic exercises and can be performed by HD patients.

Comparison of intradialytic continuous and interval training on hemodynamics and dialysis adequacy: A crossover randomized controlled trial

AIM

Circulating blood volume (BV) during exercise changes depending on the intensity and duration, and post-exercise hypotension is observed after continuous exercise. We investigated the safety and efficacy of both interval and continuous IDE at anaerobic threshold (AT) levels with respect to hemodynamic stability and dialysis efficiency.

METHODS

In this crossover randomized controlled trial, 16 patients on haemodialysis were subjected to three trial arms, including non-IDE, interval-IDE, and continuous-IDE arms. Systolic blood pressure (SBP), BV, and ultraviolet absorbance - an indicator of dialysis efficiency - were continuously measured, and each change was compared between the three arms by two-way analysis of variance.

RESULTS

Continuous IDE decreased SBP from post-exercise to the end of dialysis compared with baseline (pre 142.8 ± 19.0 vs. post 127.5 ± 24.5 mmHg, p = .02), whereas interval IDE maintained better SBP levels post-exercise (pre 139.9 ± 17.1 vs. post 140.1 ± 15.8 mmHg, p = 1.0) than continuous IDE (non-IDE 133.2 ± 19.9 vs. interval 140.1 ± 15.8 vs. continuous 127.5 ± 24.5 mmHg, p = .04). Moreover, interval IDE caused less tiredness and few symptoms (p < .05), despite reaching higher intensity than continuous IDE (p = .001). The BV of each IDE arm decreased during exercise and recovered post-exercise to the same level as non-IDE. Ultraviolet absorbance was not different between each arm (p = .16).

CONCLUSION

AT-level interval IDE maintains better hemodynamic stability from post-exercise to the end of dialysis and may represent a novel approach that can be effectively performed with fewer symptoms.

Effects of Different Exercises on Physical Function, Dialysis Adequacy, and Health-Related Quality of Life in Maintenance Hemodialysis Patients: A Systematic Review and Network Meta-Analysis

BACKGROUND

Clinical guidelines recommend exercise training for patients undergoing maintenance hemodialysis (MHD). However, the effectiveness of different types of exercise remains uncertain.

OBJECTIVES

The aims of the study were to compare and rank the effect of different types of exercise on walking capacity, cardiorespiratory fitness, dialysis adequacy, and health-related quality of life (HRQOL) in patients undergoing MHD.

METHODS

Eight databases (four English and four Chinese) were searched from inception to January 1, 2022. Randomized controlled trials evaluating the efficacy of different exercises for patients undergoing MHD were included. Two independent reviewers screened the literature, extracted data, assessed the risk of bias, and evaluated the certainty of evidence. A frequentist random-effect network meta-analysis was conducted.

RESULTS

Ninety trials with 4,084 participants comparing 15 types of exercise were included, reporting on the six-minute walking test (45 trials), peak oxygen uptake (22 trials), dialysis adequacy (30 trials), and HRQOL (23 trials). Network meta-analysis showed that the most effective intervention for walking capacity was intradialytic aerobic exercise combined with blood flow restriction with a mean difference and 95% confidence interval of 97.35 (11.89-182.81), for peak oxygen uptake it was non-intradialytic combined aerobic and resistance exercise with a value of 4.35 (2.25-6.44), for dialysis adequacy it was intradialytic combined aerobic and resistance exercise with a value of 0.17 (0.06-0.28), for the physical component summary of HRQOL it was intradialytic aerobic exercise with a value of 4.93 (2.31-7.54), and for the mental component summary of HRQOL it was non-intradialytic combined aerobic and resistance exercise with a value of 6.36 (0.45-12.27). Ultimately, intradialytic combined aerobic and resistance exercise could improve all the above outcomes compared to usual care.

CONCLUSIONS

This study concluded that intradialytic combined aerobic and resistance exercise is optimal for MHD patients due to its significant positive effects on multiple outcomes. Walking capacity can be further enhanced by combining blood flow restriction with exercise. For improving dialysis adequacy, intradialytic exercise proves to be more effective than non-intradialytic exercise. Further well-designed clinical trials are needed to investigate the effects of exercise with varying durations, intensities, and frequencies.

Intradialytic Protein Ingestion and Exercise do Not Compromise Uremic Toxin Removal Throughout Hemodialysis

OBJECTIVE

Dietary protein and physical activity interventions are increasingly implemented during hemodialysis to support muscle maintenance in patients with end-stage renal disease (ESRD). Although muscle maintenance is important, adequate removal of uremic toxins throughout hemodialysis is the primary concern for patients. It remains to be established whether intradialytic protein ingestion and/or exercise modulate uremic toxin removal during hemodialysis.

METHODS

We recruited 10 patients with ESRD (age: 65 ± 16 y, BMI: 24.2 ± 4.8 kg/m²) on chronic hemodialysis treatment to participate in this randomized cross-over trial. During hemodialysis, patients were assigned to ingest 40 g protein or a nonprotein placebo both at rest (protein [PRO] and placebo [PLA], respectively) and following 30 min of exercise (PRO + exercise [EX] and PLA + EX, respectively). Blood and spent dialysate samples were collected throughout hemodialysis to assess reduction ratios and removal of urea, creatinine, phosphate, cystatin C, and indoxyl sulfate.

RESULTS

The reduction ratios of urea and indoxyl sulfate were higher during PLA (76 ± 6% and 46 ± 9%, respectively) and PLA + EX interventions (77 ± 5% and 45 ± 10%, respectively) when compared to PRO (72 ± 4% and 40 ± 8%, respectively) and PRO + EX interventions (73 ± 4% and 43 ± 7%, respectively; protein effect: P = .001 and P = .023, respectively; exercise effect: P = .25 and P = .52, respectively). Nonetheless, protein ingestion resulted in greater urea removal (P = .046) during hemodialysis. Reduction ratios and removal of creatinine, phosphate, and cystatin C during hemodialysis did not differ following intradialytic protein ingestion or exercise (protein effect: P > .05; exercise effect: P>.05). Urea, creatinine, and phosphate removal were greater throughout the period with intradialytic exercise during PLA + EX and PRO + EX interventions when compared to the same period during PLA and PRO interventions (exercise effect: P = .034, P = .039, and P = .022, respectively).

CONCLUSION

The removal of uremic toxins is not compromised by protein feeding and/or exercise implementation during hemodialysis in patients with ESRD.

Glucose as a Risk Factor for Periodontitis in Kidney Transplantation Patients

BACKGROUND

Various factors including diabetes and oxidative stress are associated with periodontal inflammation. End-stage renal disease causes various systemic abnormalities in patients, including cardiovascular disaese, metabolic abnormalities, and infection. Even after kidney transplantation (KT), these factors are known to be associated with inflammation. Our study, therefore, aimed to study risk factors associated with periodontitis in KT patients.

METHODS

Patients who visited Dongsan Hospital, Daegu, Korea since 2018 and have undergone KT were selected. As of November 2021, 923 participants, with full data including hematologic factors were studied. Periodontitis was diagnosed based on residual bone level in panoramic views. Patients were studied by the presence of periodontitis.

RESULTS

From 923 KT patients, 30 were diagnosed with periodontal disease. Fasting glucose levels were higher in patients with periodontal disease, and total bilirubin levels were lower. When divided by fasting glucose levels, high glucose level showed increase of periodontal disease with odds ratio of 1.031 (95% confidence interval 1.004-1.060). After adjusting for confounders, the results were significant with odds ratio of 1.032 (95% CI 1.004-1.061).

CONCLUSIONS

Our study showed that KT patients, of whom uremic toxin clearance has been revolted, are yet at risk of periodontitis by other factors, such as high blood glucose levels.

The optimal exercise modality and intensity for hemodialysis patients incorporating Bayesian network meta-analysis and systematic review

Background: Physical inactivity is highly prevalent in patients with hemodialysis, and a large body of evidence reported the positive effect of different exercise modalities on their health outcomes. However, the effective dosage of exercise for hemodialysis patients still requires verification.

Objective: We aimed to determine the most effective exercise intensity and modality for improvements in physical function, blood pressure control, dialysis adequacy, and health-related quality of life for hemodialysis patients.

Design: Systematic review with network meta-analysis of randomized trials.

Data sources: Five electronic databases (PubMed, EMBASE, Web of Science, Cochrane CENTRAL, and Scopus) were searched for randomized controlled trials. Data extraction and quality appraisal were conducted by two authors independently. Data were analyzed by the R (version.3.6.2) and the Stata (version.15.0).

Result: We included 1893 patients involving four exercise modalities and six exercise intensities. Combined training (aerobic exercise plus resistance exercise) has been the top-ranking exercise modality for improving the 6-min walk test (6MWT) (surface under the cumulative ranking curve analysis (SUCRA) score, 90.63), systolic blood pressure control (SUCRA score, 77.35), and diastolic pressure control (SUCRA score, 90.56). Moreover, the top-ranking exercise intensity was moderate–vigorous for 6MWT (SUCRA score, 82.36), systolic blood pressure (SUCRA score, 77.43), and diastolic blood pressure (SUCRA score, 83.75). Regarding dialysis adequacy and health-related quality of life, we found no exercise modality or intensity superior to the placebo.

Conclusion: This network meta-analysis indicated that combined training and moderate–vigorous intensity might be the most effective interventions to improve 6MWT and blood pressure control. This finding helps further guide clinical exercise prescriptions for hemodialysis patients.

Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021268535].

Chronic hemodialysis: Evaluation of dialysis adequacy and mortality

Objective

Dialysis efficacy is one of the important issues in patients undergoing hemodialysis. This study aimed to determine the adequacy of dialysis with mortality and hospital admissions in patients undergoing hemodialysis.

Methods

This retrospective cohort study was conducted on patients who underwent dialysis. Dialysis adequacy was measured based on the Kt/V criterion. Age, sex, disease etiology, duration of dialysis, and access dialysis were evaluated.

Results

128 patients with a mean age of 61.48 ± 13.36 years were included in the study. 8 patients had a history of kidney transplantation. The mean dialysis time in the patients was 4.30 ± 3.39 years. The mean Kt/V in the patients was 1.40 ± 1.8 years. Of the 128 patients, 53 were hospitalized for cardiac or renal reasons. The number of fatalities was 9 cases out of 128. The cause of death in all the cases was heart problems. There was a statistically significant correlation between the adequacy of dialysis in terms of Kt/V and mortality, but it was not associated with hospitalization.

Conclusion

Inadequate dialysis in terms of Kt/V is likely to increase the rate of mortality among dialysis patients.

•

Dialysis efficacy is one of the important issues in patients undergoing hemodialysis.

•

Inadequate dialysis in terms of Kt/V is likely to increase the rate of mortality among dialysis patient.

•

The findings showed that there was no significant correlation between the dialysis adequacy and hospitalization.

An intradialytic aerobic exercise program ameliorates frailty and improves dialysis adequacy and quality of life among hemodialysis patients: a randomized controlled trial

Background

Hemodialysis patients with chronic kidney disease exhibit impaired exercise tolerance and functional decline. Despite the life-saving benefits of adequate dialysis, those declines translate into frailty and deteriorating quality of life (QoL). This study evaluated the effects of an intradialytic aerobic exercise program on frailty, dialysis adequacy, and QoL among hemodialysis patients.

Methods

Patients at an university hospital-affiliated hemodialysis center were randomly assigned to an exercise group (n = 18) or a control group (n = 21). The 12-week aerobic exercise program comprised 40 to 70 minutes of ergometer cycling 3 times/wk and a single education session. The control group completed only the education session. Outcomes were assessed at the time of enrollment, week 4, week 8, and week 12 using Fried’s frailty phenotype measures (gait speed, grip strength, vitality, body mass index, and physical activity), the short physical performance battery (SPPB), Kt/V urea, and the Short Form-36 questionnaire.

Results

There were significant interactions between groups and follow-up times in the frailty score (p < 0.001), gait speed (p < 0.001), SPPB (p < 0.001), and mental QoL (p = 0.03). The intention-to-treat and per-protocol analyses revealed that the exercise group exhibited significant improvements in frailty score (p < 0.001), gait speed (p < 0.001), grip strength (p < 0.001), exhaustion (p = 0.02), SPPB (p = 0.01), dialysis adequacy (p = 0.01), and physical QoL (p = 0.003).

Conclusion

An intradialytic aerobic exercise program could be a safe, feasible, and appropriate additional strategy to routine care among hemodialysis patients for improvements in frailty, dialysis adequacy, and QoL.

Rethinking Rehabilitation: A REVIEW OF PATIENT POPULATIONS WHO CAN BENEFIT FROM CARDIAC REHABILITATION

Although cardiac rehabilitation (CR) is safe and highly effective for individuals with various cardiovascular health conditions, to date there are only seven diagnoses or procedures identified by the Centers for Medicare & Medicaid Services that qualify for referral. When considering the growing number of individuals with cardiovascular disease (CVD), or other health conditions that increase the risk for CVD, it is important to determine the extent for which CR could benefit these populations. Furthermore, there are some patients who may currently be eligible for CR (spontaneous coronary artery dissection, left ventricular assistant device) but make up a relatively small proportion of the populations that are regularly attending and participating. Thus, these patient populations and special considerations for exercise might be less familiar to professionals who are supervising their programs. The purpose of this review is to summarize the current literature surrounding exercise testing and programming among four specific patient populations that either do not currently qualify for (chronic and end-stage renal disease, breast cancer survivor) or who are eligible but less commonly seen in CR (sudden coronary artery dissection, left ventricular assist device). While current evidence suggests that individuals with these health conditions can safely participate in and may benefit from supervised exercise programming, there is an immediate need for high-quality, multisite clinical trials to develop more specific exercise recommendations and support the inclusion of these populations in future CR programs.

Effect of blood volume change related to intensity of intradialytic aerobic exercise on hemodialysis adequacy: a pilot study

PURPOSE

Intradialytic exercise may improve dialysis efficiency; however, the association between changes in blood volume (BV) related to exercise intensity and solute removal kinetics remains unknown. We herein investigated the relationship between changes in BV with exercise and removal of solute molecules during hemodialysis.

METHODS

Each of the 21 hemodialysis patients underwent cardiopulmonary exercise test to measure anaerobic threshold (AT). According to the exercise intensity, patients were classified into two groups, the low group (n = 12), whose intensity was below the AT, and the high group (n = 9), whose intensity was at the AT level. Each patient completed two trial arms of resting and discontinuous exercise dialysis sessions in a randomized manner.

RESULTS

The change in BV with the exercise dialysis session in the high group decreased during exercise (p = 0.028) and remained decreased after exercise (p = 0.016), compared with the low group. In the low group, compared with routine sessions, the removal of potassium (p = 0.030), phosphate (p = 0.024), and urea nitrogen (p = 0.065) increased during exercise, but the total removal of these solutes did not change. In the high group, the removal of phosphate (p < 0.001) and urea nitrogen (p = 0.018) after exercise and even total phosphate (p = 0.027) decreased.

CONCLUSION

These findings suggest that the removal of small solute molecules is improved during exercise in intradialytic low-intensity exercise with no change in BV, and decreased after exercise in high-intensity exercise with a decrease in BV.

CLINICAL TRIALS REGISTRY

Trial retrospectively registered at the UMIN Clinical Trials Registry: study number UMIN000038629 (Registration date: September 7, 2019).

Amino acid removal during hemodialysis can be compensated for by protein ingestion and is not compromised by intradialytic exercise: a randomized controlled crossover trial

BACKGROUND

Patients with end-stage renal disease (ESRD) undergoing hemodialysis experience a rapid decline in skeletal muscle mass and strength. Hemodialysis removes amino acids (AAs) from the circulation, thereby lowering plasma AA concentrations and stimulating proteolysis.

OBJECTIVES

In the present study, we evaluate the impact of intradialytic protein ingestion at rest and following exercise on AA removal and plasma AA availability in patients with ESRD.

METHODS

Ten patients (age: 65 ± 16 y, male/female: 8/2, BMI: 24.2 ± 4.8 kg/m2, serum albumin: 3.4 ± 0.3 g/dL) with ESRD undergoing hemodialysis participated in this randomized controlled crossover trial. During 4 hemodialysis sessions, patients were assigned to ingest 40 g protein or a placebo 60 min after initiation, both at rest (PRO and PLA, respectively) and following exercise (PRO + EX and PLA + EX, respectively). Spent dialysate and blood samples were collected every 30 min throughout hemodialysis to assess AA removal and plasma AA availability.

RESULTS

Plasma AA concentrations declined by 26.1 ± 4.5% within 30 min after hemodialysis initiation during all interventions (P < 0.001, η2p > 0.79). Protein ingestion, but not intradialytic exercise, increased AA removal throughout hemodialysis (9.8 ± 2.0, 10.2 ± 1.6, 16.7 ± 2.2, and 17.3 ± 2.3 g during PLA, PLA + EX, PRO, and PRO + EX interventions, respectively; protein effect P < 0.001, η2p = 0.97; exercise effect P = 0.32, η2p = 0.11). Protein ingestion increased plasma AA concentrations until the end of hemodialysis, whereas placebo ingestion resulted in decreased plasma AA concentrations (time effect P < 0.001, η2p > 0.84). Plasma AA availability (incremental AUC) was greater during PRO and PRO + EX interventions (49 ± 87 and 70 ± 34 mmol/L/240 min, respectively) compared with PLA and PLA + EX interventions (-227 ± 54 and -208 ± 68 mmol/L/240 min, respectively; protein effect P < 0.001, η2p = 0.98; exercise effect P = 0.21, η2p = 0.16).

CONCLUSIONS

Protein ingestion during hemodialysis compensates for AA removal and increases plasma AA availability both at rest and during recovery from intradialytic exercise. Intradialytic exercise does not compromise AA removal or reduce plasma AA availability during hemodialysis in a postabsorptive or postprandial state.

Addressing feasibility challenges to delivering intradialytic exercise interventions: A theory-informed qualitative study

BACKGROUND

Intradialytic exercise (IDE) may improve physical function and health-related quality of life. However, incorporating IDE into standard hemodialysis care has been slow due to feasibility challenges. We conducted a multicenter qualitative feasibility study to identify potential barriers and enablers to IDE and generate potential solutions to these factors.

METHODS

We conducted 43 semi-structured interviews with healthcare providers and patients across twelve hospitals in Ontario, Canada. We used the Theoretical Domains Framework and directed content analysis to analyze the data.

RESULTS

We identified eight relevant domains (knowledge, skills, beliefs about consequences, beliefs about capabilities, environmental context and resources, goals, social/professional role and identity, and social influences) represented by three overarching categories: 1) Knowledge, skills and expectations: lack of staff expertise to oversee exercise, uncertainty regarding exercise risks, benefits, and patient interest, lack of knowledge regarding exercise eligibility; 2) Human, material and logistical resources: staff concerns regarding workload, perception that exercise professionals should supervise IDE; space, equipment, and scheduling conflict concerns; 3) Social dynamics of the unit: local champions and patient stories contribute to IDE sustainability.We developed a list of actionable solutions by mapping barriers and enablers to behavior change techniques. We also developed a feasibility checklist of 47 questions identifying key factors to address prior to IDE launch.

CONCLUSIONS

Evidence-based solutions to identified barriers and enablers to IDE and a feasibility checklist may help recruit and support units, staff, and patients and address key challenges to the delivery of IDE in diverse clinical and research settings.

Uremic toxins levels from the gut microbiota seem not to be altered by physical exercise in hemodialysis patients

PURPOSE

Regular physical exercise may result in many benefits to patients with chronic kidney disease (CKD) on hemodialysis (HD), including gut microbiota modulation and solute removal. The study aimed to evaluate the effects of two programs of intradialytic exercises on uremic toxins plasma levels in HD patients.

METHODS

In experiment 1, twenty HD patients [12 men, 44.1 ± 8.9 years, BMI of 23.4 ± 2.4 kg/m²] were randomized into two groups: Aerobic exercise group (AEG, n = 11) that performed aerobic exercise on an adapted exercise bike three times a week for three months (36 sessions) and Control group (CG, n = 9). In experiment 2, twenty-six HD patients [19 men, 47.6 ± 11.0 years, BMI of 25.9 ± 3.6 kg/m²] were randomized into Resistance exercise group (REG, n = 14) that performed a resistance exercise program (using elastic bands and ankle cuffs with both lower limbs) monitored three times a week, during six months (72 sessions) and CG (n = 12). P-cresyl sulfate (p-CS), indoxyl sulfate (IS), and indol-3-acetic acid (IAA) plasma levels were determined by high-performance liquid chromatography (HPLC) with fluorescent detection.

RESULTS

The uremic toxins plasma levels did not reduce in both exercise programs, aerobic exercise (IS: 32.7 ± 14.0 vs 33.0 ± 15.4 mg/L, p = 0.86; p-CS: 59.9 ± 39.3 vs 60.0 ± 41.2 mg/L, p = 0.99; IAA: 2233 [1488-2848] vs 2227 [1275-2824] µg/L, p = 0.72) and resistance exercise (IS: 28.3 ± 11.3 vs 29.1 ± 9.7 mg/L, p = 0.77; p-CS: 31.4 ± 21.3 vs 34.2 ± 19.8 mg/L, p = 0.63; IAA: 1628 [1330-3530] vs 2000 [971-3085] µg/L, p = 0.35) in HD patients.

CONCLUSION

According to our findings, physical exercise does not appear to alter the levels of uremic toxins produced by the gut microbiota in HD patients.

Improving dialysis adequacy and quality of life in patients undergoing hemodialysis with twice a week range of motion exercise

The study aimed to determine the effects of giving range of motion (ROM) twice a week as a form intradialytic exercise on patients' dialysis adequacy and quality of life. A total of 48 eligible participants were recruited and completed this study. The intervention group (n = 24) received twice a week ROM exercise over a 4 weeks period. The outcomes were assessed at pretest and at the end of the intervention. The study shows that ROM exercise was effective in improving dialyis adequacy that include ureum retention ratio (p= 0.027) and Kt/V (p= 0.017). Quality of life improved significantly particularly in the domains of symptom and effect of kidney disease. Integrating ROM into dialysis care shows as a potential intervention to improve dialysis adequacy and quality of life for patients undergoing hemodialysis. Future research should evaluate its efficacy using a randomized clinical trial design and larger sample of patients.

Exercise and sports after COVID-19-Guidance from a clinical perspective

SARS‐CoV‐2 infection has emerged as not only a pulmonary but also potentially multi‐organ disease, which may cause long‐term structural damage of different organ systems including the lung, heart, vasculature, brain, liver, kidney, or intestine. As a result, the current SARS‐CoV‐2/COVID‐19 pandemic will eventually yield substantially increased numbers of chronically diseased patients worldwide, particularly suffering from pulmonary fibrosis, post‐myocarditis, chronic heart failure, or chronic kidney disease. Exercise recommendations for rehabilitation are complex in these patients and should follow current guidelines including standards for pre‐exercise medical examinations and individually tailored exercise prescription. It is of utmost importance to start exercise training at an early stage after COVID‐19 infection, but at the same time paying attention to the physical barriers to ensure safe return to exercise. For exercise recommendations beyond rehabilitation programs particularly for leisure time and elite athletes, more precise advice is required including assessment of sports eligibility and specific return‐to‐sports exercise programs. Because of the current uncertainty of long‐term course of SARS‐CoV‐2 infection or COVID disease, long‐term follow‐up seems to be necessary.

The impact of intradialytic exercise on immune cells expressing CCR5+ in patients with chronic kidney disease: A cross-over trial

The C-C chemokine receptor type 5 (CCR5) plays a role in the immunopathogenesis of chronic kidney disease (CKD). Exercise has anti-inflammatory properties that may contribute to the rehabilitation of CKD patients. To date, the impact of the intradialytic exercise on CCR5 expression in monocytes and lymphocytes of CKD patients is unknown. We aimed to evaluate the effects of an acute intradialytic moderate-intensity exercise on CD4+CCR5+ T-cells and CD14+CCR5+ monocytes of elderly individuals with Chronic Kidney Disease (CKD). Eight CKD elderly patients performed a single bout of 20 min intradialytic exercise and a control hemodialysis (HD) session. Blood samples were collected at baseline, during and immediately after the trials. HD therapy increased the peripheral frequency of CD4+CCR5+ T-cells. The systemic CCL5 levels and the peripheral CD14+CCR5+ proportions increased during and after HD therapy. No significant alterations in CD4+CCR5+ and CD14+CCR5+ proportions or CCL5 levels were identified in CKD patients during and after intradialytic exercise. A negative correlation between the peripheral frequency of CD14+CCR5+ and the creatinine levels was identified in the intradialytic exercise session. A single moderate-intensity intradialytic exercise imposes an immunomodulatory impact in CKD elderly patients, preventing an excessive inflammatory response induced by hemodialysis.

Intradialytic exercise in end-stage renal disease: An umbrella review of systematic reviews and/or meta-analytical studies

OBJECTIVES

This umbrella review aimed to understand the clinical benefits and adverse events associated with different modalities of intradialytic exercise in patients with end-stage renal disease undergoing hemodialysis.

DATA SOURCES

The search was performed until September 10th, 2020 on Scopus, Web of Science, the Cochrane Database, CINAHL, and PubMed.

METHODS

This umbrella review was conducted following the PRISMA guideline statement. The methodological quality of the reviews was assessed with the AMSTAR-2. Standardized mean differences with 95% confidence intervals were estimated. The I-squared statistic was used to assess heterogeneity and the Eggers' test was performed to test asymmetry/small-study effects.

RESULTS

Eleven reviews were included and 48 unique meta-analyses were examined. Nine were supported by suggestive evidence (P < 0.05, small heterogeneity, absence of small-study effects, and excess significance bias). Clinical benefits were found for functional capacity associated with aerobic exercise (d = 0.81; k = 6), resistance training (d = 0.58; k = 6), neuromuscular electrical stimulation (d = 0.70; k = 5), and inspiratory muscle training (d = 1.13; k = 2), measured by the distance covered in the 6-minutes walking test. This outcome was also associated with aerobic exercise (d = 0.28; k = 7) and combined exercise, measured by VO2peak (d = 1.01; k = 5) and by the duration of the cardiopulmonary test (d = 1.07; k = 4). Isometric quadriceps muscle strength improved with neuromuscular electrical stimulation (d = 1.19; k = 7) while patients' perception of vitality improved with combined exercise (d = 0.60; k = 3).

CONCLUSIONS

Suggestive evidence was found for the associations between various modalities of intradialytic exercise and functional capacity. Combined exercise was associated with improvements in physical and psychosocial variables. Few or no adverse events were reported.

Being on hemodialysis during the COVID-19 outbreak: A mixed-methods' study exploring the impacts on dialysis adequacy, analytical data, and patients' experiences

For individuals with end-stage renal disease (ESRD), the novel coronavirus can present several additional challenges in disease self-management. This study aimed to explore the impacts of the COVID-19 pandemic in non-COVID-19 patients with ESRD undergoing in-center hemodialysis (HD). A mixed-methods study was conducted with a purposive sample recruited from one dialysis unit in Portugal. Quantitative data were collected retrospectively from patients' medical records from February 2020 (T1-before the outbreak) and from April 2020 (T2-during lockdown). Semi-structured interviews were conducted with 20 patients (66.9 ± 11.9 years old) undergoing HD for an average of 46.1 months (±39.5) in April 2020. Overall results suggested that dialysis adequacy and serum albumin levels decreased significantly at T2, while phosphorus levels increased. The findings from thematic analysis suggested several psychosocial negative impacts and impacts on disease and treatment-related health behaviors (eg, difficulties managing dietary restrictions during the lockdown and diminished physical activity), which can partially explain these quantitative results. However, some patients were also able to find positive impacts in this experience and problem-focused and emotional strategies were identified to cope with the demands of COVID-19. Several recommendations have been made to mitigate patients' emotional, relational, and educational unmet needs during the current pandemic and in the event of new outbreaks.

The impact of intradialytic cycling on the removal of protein-bound uraemic toxins: A randomised cross-over study

The evidence on impact of intradialytic exercise on the removal of urea, is conflictive. Impact of exercise on kinetics of serum levels of protein-bound uraemic toxins, known to exert toxicity and to have kinetics dissimilar of those of urea, has so far not been explored. Furthermore, if any effect, the most optimal intensity, time point and/or required duration of intradialytic exercise to maximise removal remain obscure. We therefore studied the impact of different intradialytic cycling schedules on the removal of protein-bound uraemic toxins during haemodialysis (HD).This randomised cross-over study included seven stable patients who were dialysed with an FX800 dialyser during three consecutive midweek HD sessions of 240 min: (A) without cycling; (B) cycling for 60 min between 60th and 120th minutes of dialysis; and (C) cycling for 60 min between 150th and 210th minutes, with the same cycling load as in session B. Blood and dialysate flows were respectively 300 and 500 mL/min. Blood was sampled from the blood inlet at different time points, and dialysate was partially collected (300 mL/h). Small water soluble solutes and protein-bound toxins were quantified and intradialytic reduction ratios (RR) and overall removal were calculated per solute.Total solute removal and reduction ratios were not different between the three test sessions, except for the reduction ratios RR_60-120 and RR_150-210 for potassium.In conclusion, we add evidence to the existing literature that, regardless of the timing within the dialysis session, intradialytic exercise has no impact on small solute clearance, and demonstrated also a lack of impact for protein-bound solutes.

Green nephrology and eco-dialysis: a position statement by the Italian Society of Nephrology

High-technology medicine saves lives and produces waste; this is the case of dialysis. The increasing amounts of waste products can be biologically dangerous in different ways: some represent a direct infectious or toxic danger for other living creatures (potentially contaminated or hazardous waste), while others are harmful for the planet (plastic and non-recycled waste). With the aim of increasing awareness, proposing joint actions and coordinating industrial and social interactions, the Italian Society of Nephrology is presenting this position statement on ways in which the environmental impact of caring for patients with kidney diseases can be reduced. Due to the particular relevance in waste management of dialysis, which produces up to 2 kg of potentially contaminated waste per session and about the same weight of potentially recyclable materials, together with technological waste (dialysis machines), and involves high water and electricity consumption, the position statement mainly focuses on dialysis management, identifying ten first affordable actions: (1) reducing the burden of dialysis (whenever possible adopting an intent to delay strategy, with wide use of incremental schedules); (2) limiting drugs and favouring "natural" medicine focussing on lifestyle and diet; (3) encouraging the reuse of "household" hospital material; (4) recycling paper and glass; (5) recycling non-contaminated plastic; (6) reducing water consumption; (7) reducing energy consumption; (8) introducing environmental-impact criteria in checklists for evaluating dialysis machines and supplies; (9) encouraging well-planned triage of contaminated and non-contaminated materials; (10) demanding planet-friendly approaches in the building of new facilities.