Effects of intradialytic exercise on functional capacity in patients with end-stage chronic kidney disease: a systematic review and meta-analysis.

The study aimed to investigate the effect of intradialytic exercise training programmes on the submaximal functional capacity of patients with kidney failure. We searched for randomized clinical trials that assessed submaximal functional capacity using the 6-min walk test (6 MWT) in adult patients on maintenance haemodialysis submitted to intradialytic physical training. The search was performed on 15 October 2021, in different databases. Random-effect, multivariate meta-regression adjusted for multiplicity were performed to examine the relationship between exercise effect and covariates. Intradialytic physical exercise induced greater changes in 6MWT distance (k = 18; n = 1,458; WMD: 37.0; 95% CI 29.3; 50.6 metres) than control groups, with substantial heterogeneity (I2 = 78.3%). Aerobic, strength, and combined exercise promoted an average increase of 48.7 (95%CI 30.9; 66.4 metres), 16.9 (95%CI 7.6; 26.3 metres), and 75.8 (95%CI 55.1; 96.6 metres) metres, respectively. Strength training resulted in inferior gains in 6MWT distance compared to aerobic training (WMD: -25.0; 95%CI: -49.1; -0.9). Intervention length shorter than 11 weeks (WMD: 37.0; 95%CI: -5.4; 79.3 metres) did not induce greater changes in 6MWT compared to control groups. There was a positive response in submaximal functional capacity to intradialytic training in kidney failure patients on maintenance haemodialysis.

Intradialytic exercise with blood flow restriction is more effective than conventional exercise in improving walking endurance in hemodialysis patients: a randomized controlled trial.

OBJECTIVE: This study aims to compare the effect of intradialytic aerobic exercise with blood flow restriction, without blood flow restriction (conventional) and no exercise (control) on muscle strength and walking endurance among chronic kidney disease patients. DESIGN: Open label and parallel group randomized controlled trial. SUBJECTS: Adult patients with chronic kidney disease on hemodialysis. INTERVENTION: A 12-week intradialytic training with or without blood flow restriction compared with a control group. MAIN MEASURES: Strength and walking endurance were measured using thoracolumbar dynamometry and a 6-minute walk test, respectively, before and after training. RESULTS: A total of 66 patients were randomized into three groups: blood flow restriction group (n = 22), conventional exercise group (n = 22) and control group (n = 22). There were seven dropouts, and 59 patients were included in the analysis. There was a significant increase in the 6-minute walking distance in the blood flow restriction group (from 412.7 (115.9) to 483.0 (131.0) m, P = 0.007) in comparison with the conventional exercise group (from 426.79 (115.00) to 433.2 (120.42) m, not significant) and the control group (from 428.4 (108.1) to 417.3 (100.2) m, not significant). The change in the walking distance over time was significantly different among groups (intervention group/time, P = 0.02). The simple effects test found a significant time effect only in the blood flow restriction group. There was no significant difference in strength change between the groups. CONCLUSION: Among chronic kidney disease patients, intradialytic exercise of low/moderate intensity with blood flow restriction was more effective in improving walking endurance than conventional exercise or no exercise.

Does Intradialytic Exercise Improve Removal of Solutes by Hemodialysis? A Systematic Review and Meta-analysis.

OBJECTIVE: To describe a systematic review and meta-analysis to identify if intradialytic exercise improves the removal of solutes and the hemodialysis adequacy. DATA SOURCES: A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed. The sources were MEDLINE (via PubMed), Web of Science, LILACS, and SciELO, from inception until July 2018. STUDY SELECTION: Clinical trials including patients on chronic hemodialysis submitted to the intervention of aerobic intradialytic exercise. DATA EXTRACTION: Evaluating as outcomes the removal of solutes (creatinine, phosphate, potassium) and/or adequacy parameters (Kt/V-urea). DATA SYNTHESIS: The systematic review included 23 studies (7 evaluating the effect of 1 exercise session and 16 evaluating the effect of training, lasting from 6 to 25 weeks). Eleven RCT were included in the meta-analyses. It was observed that the aerobic intradialytic exercise increased the Kt/V-urea (0.15; 95% confidence interval [95% CI], 0.08-0.21) and decreased creatinine (-1.82 mg/dL; 95% CI, -2.50 to -1.13), despite the high heterogeneity of the analysis. No differences were found in phosphorus and potassium removal. CONCLUSION: The aerobic intradialytic exercise may be suggested to improve the Kt/V-urea and the creatinine removal during the dialysis.

A new technique for low-volume continuous sampling of spent dialysate: a validation study.

The measure of hemodialysis (HD) adequacy recommended nowadays by most guidelines, Kt/V-urea, presents significant drawbacks. Direct dialysis quantification (DDQ) through total dialysate collection (TDC), considered the gold standard measure of HD adequacy, is cumbersome, which precludes its widespread use in clinical practice. The present study aims to validate a low-volume continuous sampling of spent dialysate (CSSD). Cross-sectional study carried out at a university hospital. Throughout 4-h hemodialysis sessions, urea removal was measured by three DDQ methods: TDC, CSSD, and fractional sampling of dialysate (FSD). The primary outcome was the comparison between the total mass of urea removed measured by TDC and the dialysate sampling techniques. The comparison between urea distribution volume (UDV) estimated by anthropometric method and through DDQ was a secondary outcome. The analysis was done through linear regression and Bland-Altman concordance method. Twenty HD sessions were studied. The mean amount of urea collected in TDC and calculated from the 40-mL sample of CSSD were 33.70 ± 11.70 g and 33.90 ± 11.70 g, respectively [r 0.96, p < 0.0001; bias - 0.2 (95% CI - 1.8 to 1.4); limits of agreement - 6.8 to 6.4]. The anthropometric measure, when compared with DDQ method, underestimated UDV in patients with smaller body size. This new simple, inexpensive, and small volume CSSD technique can provide accurate information about the total amount of solutes removed by hemodialysis.

Exploring the complexity: the interplay between the angiotensin-converting enzyme insertion/deletion polymorphism and the sympathetic response to hemodialysis.

Patients on hemodialysis (HD) are at increased risk for arrhythmias and sudden cardiac death. Autonomic nervous system (ANS) dysfunction seems to participate in the arrhythmogenic process. Genetic factors have an impact on ANS modulation, but the specific role of the insertion/deletion (I/D) polymorphism in the gene for angiotensin-converting enzyme (ACE) has not been investigated. Since the D allele increases gene expression, it is a candidate polymorphism to interact with the ANS. The aim of the present study was to compare the behavior of heart rate variability (HRV) during HD, as a surrogate for ANS response to stressors, between the ACE genotypes. In a sample of patients with chronic kidney disease I/D ACE genotypes were assessed with PCR and HRV was measured before, in the second hour, and after a HD session. HRV parameters in the time and frequency domains were analyzed by repeated-measures mixed models according to the time of measurement and ACE polymorphism. HRV parameters in the frequency domain presented significantly different variations during the HD session between patients with or without the D allele. Only patients with the II genotype presented an increase in low-frequency normalized units and in the low frequency-to-high frequency ratio throughout HD. Patients with the II genotype seemed to have a more physiological response to the volemic and electrolytic changes that occur during HD, with greater sympathetic activation than patients with ID and DD genotypes. NEW & NOTEWORTHY Adding to the effort to understand the complexity of cardiovascular system regulation, we have found that the autonomic nervous system response to the acute volume removal during hemodialysis may be different between angiotensin-converting enzyme insertion/deletion polymorphisms. To our knowledge, this is the first time that this specific interaction was analyzed during a volume removal intervention.

Comparative effectiveness of 30 % trisodium citrate and heparin lock solution in preventing infection and dysfunction of hemodialysis catheters: a randomized controlled trial (CITRIM trial).

BACKGROUND: Central venous catheters (CVC) are the only option when hemodialysis is needed for patients without definitive vascular access. However, CVC is associated with complications, such as infection, thrombosis, and dysfunction, leading to higher mortality and expenditures. The aim of this study was to compare the effectiveness of 30 % trisodium citrate (TSC30 %) with heparin as CVC lock solutions in preventing catheter-related bloodstream infections (CRBSI) and dysfunction in hemodialysis patients. METHODS: Randomized, double-blind controlled trial comparing the event-free survival of non-tunneled CVC locked with heparin or TSC30 % in adult hemodialysis patients. RESULTS: The study included 464 catheters, 233 in heparin group, and 231 in TSC30 % group. The CRBSI-free survival of TSC30 % group was significantly shorter than that of heparin group. When stratified by insertion site, heparin was better than TSC30 % only in subclavian CVC. The dysfunction-free survival was not different between groups in the main analysis, but there is also a shorter survival among subclavian CVC locked with TSC30 % in stratified analysis. CONCLUSION: There was no difference on CRBSI-free or dysfunction-free survival between jugular vein CVC locked with heparin or 30 % citrate. However, subclavian CVC locked with 30 % citrate presented shorter event-free survival. This difference may be related to anatomical and positional effects, CVC design, and hydraulic aspects of the lock solution. CLINICALTRIALS. GOV IDENTIFIER: NCT02563041.

From the 1990s to CORAL (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) trial results and beyond: does stenting have a role in ischemic nephropathy?

The prevalence of atherosclerotic renal artery stenosis is high, ∼7% in individuals older than 65 years and ∼50% in patients with diffuse arterial disease, and it is increasingly frequent in an aging population. About 10% to 15% of atherosclerotic renal artery stenosis cases lead to the development of resistant hypertension and/or ischemic nephropathy. The management of ischemic nephropathy may include medical therapy and/or revascularization. In the past, revascularization required surgical bypass or endarterectomy, accompanied by the morbidity and mortality associated with a major surgical procedure. During the last few decades, less invasive endovascular procedures such as percutaneous transluminal renal artery angioplasty with stent placement have become available. At the same time, new antihypertensive and cardiovascular drugs have been developed, which may preclude revascularization, at least in some cases. The indications of each of these therapeutic options have changed over time. This review offers a temporal perspective on the course of technical and scientific advances and the accompanying change in clinical practice for the treatment of ischemic nephropathy. The latest randomized clinical trials, including the CORAL (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) trial, the largest on the subject, as well as a meta-analysis of these studies, have indicated that the best approach is medical therapy alone. There is evidence that revascularization brings no additional benefit, at least in low-risk and stable atherosclerotic renal artery stenosis. High-risk patients, especially those with recurrent flash pulmonary edema, could benefit from percutaneous transluminal renal artery angioplasty and stent placement, but there is no definitive evidence and the treatment choice should take into account the risks and potential benefits of the procedure.

Acetylsalicylic acid mitigates erythropoietin-associated blood pressure increase in nonuremic rats.

BACKGROUND: Approximately 30% of the chronic kidney disease patients using recombinant human erythropoietin (rhuEPO) have an increase in blood pressure (BP). Its mechanism and whether it depends on renal function remain unclear. There is early evidence that acetylsalicylic acid (ASA) prevents the rhuEPO-induced increase in BP. This study aims to verify whether very high doses of rhuEPO can increase BP in nonuremic rats and whether the co-administration of ASA can prevent it. METHODS: Forty male Wistar rats were divided into four groups: placebo/placebo; placebo/rhuEPO 200 UI/kg thrice weekly; placebo/ASA 50 mg/kg daily; rhuEPO 200 UI/kg thrice weekly/ASA 50 mg/kg daily. Hematocrit was measured before and after and systolic BP was measured weekly by tail-cuff technique. Direct measurement of the BP was obtained at the end. RESULTS: The rhuEPO groups had higher final hematocrit (rhuEPO/placebo 56.7 ± 7.6, rhuEPO/ASA 56.7 ± 7.7; p < 0.001 versus placebo/placebo, 42.2 ± 4.7 and ASA/placebo 41.2 ± 4.2); and also increase in systolic BP (rhuEPO/placebo 135.1 ± 15.0, p = 0.01 and rhuEPO/ASA 127.2 ± 6.8, p = 0.02), whereas BP in rats from placebo/placebo (120.9 ± 5.0, p = 0.18) and placebo/ASA (124.6 ± 13.3, p = 0.12) groups remained unchanged. By direct measurement, the final BP was higher in rhuEPO/placebo (DBP 123.1 ± 12.0; SBP 157.4 ± 12.5; MBP 139.8 ± 11.9) than placebo/placebo (DBP 105.1 ± 11.5; SBP 141.0 ± 12.6; MBP 122.1 ± 12.1) and placebo/ASA groups (DBP 106.6 ± 8.1; SBP 141.5 ± 8.4, MBP 122.1 ± 7.2) (p < 0.05 by post hoc Bonferroni test ANOVA). The rhuEPO/ASA group (PAD 115.1 ± 11.4, PAS 147.4 ± 9.1, MBP 130.1 ± 10.3) was not different from other groups. CONCLUSIONS: The administration of very high doses of rhuEPO is associated with an increase in hematocrit and BP in nonuremic rats. The concomitant use of ASA mitigates the rhuEPO-associated BP increase.

COVID-19 is more lethal in hemodialysis chronic kidney disease patients with low physical capacity.

INTRODUCTION: The mortality rate in patients on maintenance hemodialysis (HD) is high and is associated with low functional capacity (FC). We analyzed the association of FC and COVID-19 lethality among HD patients. METHODS: A cohort study that included evaluations of FC in patients on HD was underway, and the association between FC and lethality was included as an ad-hoc outcome. RESULTS: One hundred and twelve patients were submitted to a physical, 31 patients contracted symptomatic COVID-19, 20 recovered and 11 died (lethality rate of 35.5%). There was a difference between survivors and non-survivors on six-minutes-walking-test (6MWT) 386.1 ± 112.8 versus 296.9 ± 103.3 meters (p = 0.04), 30 s sit-to-stand test (30CST) score 11.7 ± 3.1 versus 7.7 ± 4.1 (p = 0.006), and timed up and go test (TUG) 9.4 versus 13.6 s (p = 0.009). There was also an association between percentages of predicted 6MWT, 30CST, and TUG with COVID-19 lethality. CONCLUSION: Patients on maintenance HD with poorer physical performance presented the worst prognosis from COVID-19 pandemic.

Gender Differences in Physical Activity and Health-Related Authorships Between 1950 and 2019.

BACKGROUND: The objective of this study was to investigate gender differences in authorship in physical activity and health research. METHODS: A bibliometric study including 23,399 articles from 105 countries was conducted to estimate the participation of female researchers in physical activity publications from 1950 to 2019. The frequency of female researchers was analyzed and classified by first and last authors and the overall percentage of female authors by region and country. RESULTS: The proportion of female first authors increased from <10% in the 50s and 80s to 55% in the last decade. On the other hand, the proportion of last authors increased from 8.7% to 41.1% in the same period. Most publications with female researchers were from the United States, Canada, Australia, Brazil, the Netherlands, Spain, England, Germany, Sweden, and China. Nine of these countries had over 50% of the articles published by female first authors. However, in all 10 countries, <50% of the articles were published by female last authors. CONCLUSIONS: The proportion of female researchers increased over time. However, regional differences exist and should be addressed in gender equity policies. There is a gap in the participation of female researchers as last authors. By actively addressing the gender gap in research, the global society can harness the full potential of all talented individuals, regardless of gender, leading to more inclusive and impactful scientific advancements.

Incidence of hospital admissions in bioimpedance-guided fluid management among maintenance hemodialysis patients-Results of a randomized controlled trial.

INTRODUCTION: Hemodialysis is life-sustaining in kidney failure. However, proper regulation of body fluids depends on an accurate estimate of target weight. This trial aims to compare clinical endpoints between target weight estimation guided by bioimpedance spectroscopy and usual care in hemodialysis patients. METHODS: This is an open-label, parallel-group, controlled trial that randomized, through a table of random numbers, adult patients on maintenance hemodialysis to target weight estimation based on monthly clinical evaluation alone or added to evaluation by bioimpedance twice a year. The primary outcome was survival, and the secondary outcomes were the rate of hospital admissions, change in blood pressure (BP), and antihypertensive drugs load. Participants were followed for 2 years. Survival analysis was performed using Kaplan-Meier estimator and Log-rank test, and hospital admissions were analyzed by the incidence-rate ratio. FINDINGS: One hundred and ten patients were randomized to the usual care (52) or bioimpedance (58) groups, with a mean age of 57.4 (15.4) years, 64 (58%) males. There was no difference between the groups at baseline. Survival was not significantly different between groups (log-rank test p = 0.68), but the trial was underpowered for this outcome. There was also no difference between the groups in the change in systolic or diastolic BP or in the number of antihypertensive drugs being used. The incidence rate of hospital admissions was 3.1 and 2.1 per person-year in usual care and bioimpedance groups, respectively, with a time-adjusted incidence rate ratio of 1.48 (95% CI: 1.20-1.82, p = 0.0001) and attributable fraction of risk among exposed individuals of 0.32 (95% CI: 0.17-0.45). DISCUSSION: The inclusion of bioimpedance data to guide the estimation of target weight in hemodialysis patients had no detectable impact on survival or BP control, but significantly reduced the incidence rate of hospital admissions. The study was registered at ClinicalTrials.gov Identifier: NCT05272800.

Sarcopenia diagnosis using different criteria as a predictor of early mortality in patients undergoing hemodialysis.

OBJECTIVES: Chronic kidney disease (CKD) is a public health problem, causing secondary sarcopenia. The aim of this study was to evaluate sarcopenia using the definitions proposed by European Working Group on Sarcopenia in Older People in 2010 (EWGSOP2010) and 2019 (EWGSOP2019) as an independent prognostic factor for worse survival in patients with CKD undergoing hemodialysis. METHODS: Muscle mass, muscle strength, and physical performance were assessed in a cohort of patients with CKD on hemodialysis. The sample consisted of 127 patients (40% >60 y of age) and 36 patients (28.3%) died after a median follow-up length of 23.5 mo (interquartile range= 14.9 - 29). The EWGSOP2010 and EWGSOP2019 definitions were used for diagnosing sarcopenia. Sarcopenia association with mortality by both definitions was investigated using Kaplan-Meier curves and Cox proportional hazard models. The area under the curve, sensitivity, specificity, positive, and negative predictive values for both definitions were also compared. RESULTS: Patients diagnosed with sarcopenia by both criteria had almost three times higher risk for mortality (95% confidence interval,1.45-6.06 and 1.44-6.13, respectively). Patients classified with severe sarcopenia by both definitions had a significantly lower survival, even after the adjusted analysis. The areas under the curve for EWGSOP2010 and EWGSOP2019 did not significantly differ. The sensitivity/specificity analysis was considered similar for both criteria, and around 70% of the patients was correctly classified. CONCLUSION: Sarcopenia, notably severe sarcopenia, diagnosed by EWGSOP2010 or EWGSOP2019 criteria, is an independent prognostic factor for worse survival in this population. Early detection with effective interventions may decrease the higher mortality risk among patients with sarcopenia and CKD.

Effects of a 16-week physical training on clinical outcomes in patients with hypertension and chronic kidney disease: NEPHROS post-trial follow-up.

The NEPHROS is a randomized controlled trial which applied a 16-week aerobic and resistance training to patients with chronic kidney disease (CKD) and high blood pressure. This report describes a long-term post-trial follow-up, comparing survival, health-related quality of life (HRQoL), and estimated glomerular filtration rate (GFR) change between the intervention and control groups according to in-trial cardiovascular risk factors. Three years after the original trial, NEPHROS participants were re-evaluated. Cox proportional hazards model was used to compare survival time and linear regression for changes in GFR and physical and mental HRQoL summary scores between intervention and control groups according to age, sex, and in-trial GFR, C-reactive protein, glucose, lipids, ankle-brachial index (ABI), functional capacity, and blood pressure. Of the 150 participants of NEPHROS, 128 were included in the long-term analysis. The previous exercise training had no effects on survival, GFR, or HRQoL. Baseline in-trial GFR (HR = 0.95, 95%CI: 0.92; 0.98) and ABI (HR = 0.03, 95%CI: 0.002; 0.43) were positive independent predictors for survival. Lower ABI (coefficient = 9.00, 95%CI: 0.43; 17.5) and higher systolic blood pressure (coefficient = -0.13, 95%CI: -0.24; -0.03) were independent predictors for GFR decline. A 16-week exercise program had no long-term effect on survival, quality of life, or glomerular filtration in patients with CKD stages 2 to 4. Lower GFR and ABI and higher systolic blood pressure were associated with poorer prognosis among CKD patients.

Overhydration in acute kidney injury: Is it always a menace to critically ill patients? A survival study using bioimpedance spectroscopy.

INTRODUCTION: The hydration status is a predictor of survival in critically ill patients. However, it is unclear whether this association depends on the patient clinical condition. This study was designed to analyze the impact of hydration status on survival of critically ill patients with acute kidney injury (AKI) with or without sepsis. METHODS: A prospective cohort study following critically ill patients with AKI consecutively admitted over a one-year period to a teaching hospital intensive care unit (ICU). All patients with AKI stage three or higher of the KDIGO score were included. The hydration status was evaluated through the overhydration (OH) parameter of spectroscopy bioimpedance and sepsis was defined according Sepse-3 criteria. The survival analysis used adjusted competing-risks regression. RESULTS: Forty-eight patients were included, 27 (56%) with a sepsis diagnosis. The main negative predictors of survival among sepsis patients, adjusted by SAPS3 score, were higher OH (SHR 1.1, 95% CI 1.0-1.2, p = 0.02), mechanical ventilation (SHR 6.9, 95% CI 1.0-47.8, p = 0.04) and older age (SHR 1.1, 95% CI 1.0-1.1, p = 0.005). The predictors in non-sepsis patients were lower OH (SHR 0.82, 95% CI 0.71-0.95, p = 0.008) and mechanical ventilation (SHR 12, 95% CI 2.4-6.6, p < 0.001). CONCLUSIONS: This finding suggests that extracellular overhydration is an independent predictor of survival in critically ill patients with sepsis, but it seems to have opposite effect in non-sepsis patients.

Is It Safe for Hemodialysis Patients to Seek Gains with Less Pain? Acute Hemodynamic Response to Intradialytic Blood Flow Restriction Training.

Considering that the hemodynamic safety is a major concern about intradialytic exercise with blood flow restriction, this analysis was performed to compare the blood pressure (BP) behavior during the first two hours of hemodialysis (HD) between sessions with no exercise (control group, CG), low/moderate intensity aerobic exercise with blood flow restriction (BFRE) and conventional aerobic exercise (AE). Adult patients with chronic kidney disease on HD at a university hospital were randomly assigned and submitted to a 12-week intradialytic training with BFRE or AE compared with the CG group. The main outcomes of this report were the change in systolic (SBP) and diastolic (DBP) BP during HD and the frequency of low BP (LBP) and high BP (HBP) episodes. A total of 6,074 BP measurements of 58 patients were analyzed. There was a larger decrease in BP in the exercise sessions compared with the control sessions, but with a similar magnitude in the BFRE and AE groups (effect size 0.49). There was a higher number of LBP in the BFRE group. The frequency of HBP was similar between the BFRE and the CG groups and lower in the AE group. Despite a greater number of mild LBP in BFRE patients, the BP change during the first two hours of HD was similar to that of patients in AE. Intradialytic aerobic exercise with blood flow restriction does not seem to be associated with a higher hemodynamic burden than conventional aerobic exercise.

Antibiotic resistance pattern in urine cultures from community-dwelling women in southern Brazil - a cross-sectional study short communication.

OBJECTIVE: The increase in antibiotic resistance (AR) is a global phenomenon with regional variation. This survey aims to describe the AR in urine cultures of women from the community in a southern Brazil city. METHODS: A retrospective cross-sectional single-center study in urine cultures of community dwelling individuals. The main outcome was the AR profile of bacterial isolates from women in outpatient care. RESULTS: From 4,011 urine cultures, 524 were positive (91% from women). The most frequently isolated bacteria were Escherichia coli (E. coli) (67.0%) and Klebsiella spp. (19.4%). E. coli presented low resistance to nitrofurantoin (3.7%), moderate to levofloxacin (15.6%), amoxacillin-clavulonate (16.4%) and ciprofloxacin (17.4%), and high to trimethoprim-sulfamethoxazole (26.9%). CONCLUSIONS: Nitrofurantoin seems to be the best choice for the empirical treatment of low urinary tract infections in women, whereas sulfonamides are no longer an option, since E. coli resistance to this drug is above 20%.

Intradialytic exercise with blood flow restriction: Something to add to hemodialysis adequacy? Findings from a crossover study.

INTRODUCTION: Hemodialysis (HD) increases the lifespan of chronic kidney disease (CKD) patients. However, HD is only partially effective in replacing renal function. The aim of this study is to compare HD adequacy between sessions with intradialytic exercise with or without blood flow restriction (BFR) with sessions without exercise. METHODS: A crossover study including 22 adult CKD patients on HD. The patients were assigned to BFR (n = 11) or exercise alone group (n = 11). Each patient was submitted to four HD sessions (two with exercise and two control sessions). HD adequacy was assessed by equilibrated Kt/V-urea (eKT/V), single-pool Kt/V-urea (sp-Kt/V), urea and phosphorus rebound, urea reduction ratio (URR) and removal of urea and phosphorus in dialysate. FINDINGS: BFR exercise improved eKt/V and sp-Kt/V (1.32 ± 0.21 vs. 1.10 ± 0.16 for control, P < 0.001; 1.53 ± 0.26 vs. 1.27 ± 0.19 for control, P < 0.001, respectively) and URR (72.5 ± 5.4% vs. 66.1 ± 7.7% for control, P < 0.001). No difference in eKt/V, sp-Kt/V or URR could be detected between exercise alone and control HD sessions. Urea rebound was lower in BFR exercise vs. control sessions (-8.9 ± 9.1% vs. 30.7 ± 12.8%, P < 0.01) and exercise alone vs. control sessions (13.3 ± 29.0% vs. 42.4 ± 15.3%, P < 0.01). Phosphorus rebound was marginally lower in exercise vs. control sessions (14.4 ± 19.1% vs. 28.4 ± 22.1%, P = 0.18). Urea and phosphorus mass removal in dialysate were marginally higher in exercise vs. control sessions (42.2 ± 19.4 g vs. 35.7 ± 12.5 g, P = 0.24; 912.1 ± 360.9 mg vs. 778.6 ± 245.1 mg, P = 0.28). CONCLUSIONS: Intradialytic exercise with BFR was more effective than standard exercise in increasing HD adequacy.