Longer dialysis session length is associated with better intermediate outcomes and survival among patients on in-center three times per week hemodialysis: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Frailty in patients on dialysis

Frailty is a condition that is frequently observed among patients undergoing dialysis. Frailty is characterized by a decline in both physiological state and cognitive state, leading to a combination of symptoms, such as weight loss, exhaustion, low physical activity level, weakness, and slow walking speed. Frail patients not only experience a poor quality of life, but also are at higher risk of hospitalization, infection, cardiovascular events, dialysis-associated complications, and death. Frailty occurs as a result of a combination and interaction of various medical issues in patients who are on dialysis. Unfortunately, frailty has no cure. To address frailty, a multifaceted approach is necessary, involving coordinated efforts from nephrologists, geriatricians, nurses, allied health practitioners, and family members. Strategies such as optimizing nutrition and chronic kidney disease-related complications, reducing polypharmacy by deprescription, personalizing dialysis prescription, and considering home-based or assisted dialysis may help slow the decline of physical function over time in subjects with frailty. This review discusses the underlying causes of frailty in patients on dialysis and examines the methods and difficulties involved in managing frailty among this group.

Prevalence and factors associated with the correlation between malnutrition and pain in hemodialysis patients

Malnutrition and pain are common in patients with chronic kidney disease who undergo hemodialysis. Although both pain and malnutrition are associated with increased morbidity and mortality, few studies have explored the correlation between pain and nutritional status. This study aimed to investigate the factors associated with pain intensity in patients undergoing hemodialysis, focusing on the risk of malnutrition. This was a cross-sectional study conducted at a regional dialysis center in a large tertiary hospital. Convenience sampling was used to recruit adult patients who had undergone hemodialysis for more than three months. An interviewer-administered questionnaire was used to gather sociodemographic and clinical data related to dialysis status, comorbidities, and body mass index (BMI). Pain severity and pain interference with functioning domains of the Brief Pain Index (BPI) were used to assess pain, and the malnutrition inflammation score (MIS) was used to assess nutritional status. Descriptive and inferential statistics were used to report the findings. The data were analyzed using the 25th version of the Statistical Package for the Social Sciences (IBM-SPSS) software. Of the final sample of 230 patients, 63.0% were males and 37.0% were females, with an average age of 58.3 years. Almost one-third of the participants had a BMI within the normal range (33.9%), and nearly one-third had a BMI within the underweight range (33.9%). Slightly more than half had a normal nutritional status or mild malnutrition (54.8%), while just under half had moderate or severe malnutrition (45.2%). The prevalence of pain was 47.0%. At the multivariate level, the severity of pain was associated with malnutrition (p < 0.001). Pain interference with function was associated with marital status (p = 0.045), number of comorbidities (p = 0.012), and malnutrition (p < 0.001). The MIS was positively correlated with both the severity of pain and the interference score. Pain and malnutrition were found to be prevalent in patients undergoing hemodialysis. Pain severity was associated with malnutrition, and pain interference was associated with malnutrition, marital status, and the number of comorbidities. Hemodialysis treatment should follow a patient-tailored approach that addresses pain, nutritional status, and associated chronic conditions. In addition, pain assessment and management should be included in the curriculum of nephrology training programs.

Association of calciprotein particles with serum phosphorus among patients undergoing conventional and extended-hours haemodialysis

Background and hypothesis

Extended-hours haemodialysis (HD) is associated with better clinical outcomes than conventional HD. We investigated whether extended-hours HD and conventional HD have varying effects on blood levels of calciprotein particles (CPPs) and phosphorus, which have been identified as major pathogenic molecules for vascular calcification.

Methods

Patients who underwent conventional or extended in-centre daytime HD between January and March 2020 were included. Plasma CPP levels, representing only secondary CPPs (CPP-II), were measured in pre-dialysis samples. Linear and non-linear associations between CPPs and serum phosphorus levels were examined across dialysis modalities.

Results

A total of 382 participants (185 undergoing extended-hours HD and 197 undergoing conventional HD) were included in the analysis. The median age of participants was 71 years, 65% of the patients were men and the mean phosphorus level was 5.4 mg/dl. Plasma CPP (CPP-II) levels were lower in the extended-hours HD group than in the conventional HD group [40 018 (arbitrary units) AU versus 75 728 AU; P < .01]. Multivariable linear regression analysis showed that extended-hours HD was associated with lower natural logarithmic plasma CPP (CPP-II) levels: -0.64 (95% confidence interval -0.74 to -0.55). A restricted cubic spline function indicated that extended-hours HD was associated with lower plasma CPP (CPP-II) levels across levels of serum phosphorus, with significant differences observed between groups, especially in hyperphosphataemic conditions (P for interaction <.01).

Conclusions

The extended-hours HD group had lower CPP levels than the conventional HD group despite no significant differences in serum phosphorus levels, which may contribute to better clinical outcomes in patients on extended-hours HD.

Hemodialysis Procedures for Stable Incident and Prevalent Patients Optimize Hemodynamic Stability, Dialysis Dose, Electrolytes, and Fluid Balance

The demographic profile of patients transitioning from chronic kidney disease to kidney replacement therapy is changing, with a higher prevalence of aging patients with multiple comorbidities such as diabetes mellitus and heart failure. Cardiovascular disease remains the leading cause of mortality in this population, exacerbated by the cardiovascular stress imposed by the HD procedure. The first year after transitioning to hemodialysis is associated with increased risks of hospitalization and mortality, particularly within the first 90-120 days, with greater vulnerability observed among the elderly. Based on data from clinics in Fresenius Medical Care Europe, Middle East, and Africa NephroCare, this review aims to optimize hemodialysis procedures to reduce mortality risk in stable incident and prevalent patients. It addresses critical aspects such as treatment duration, frequency, choice of dialysis membrane, dialysate composition, blood and dialysate flow rates, electrolyte composition, temperature control, target weight management, dialysis adequacy, and additional protocols, with a focus on mitigating prevalent intradialytic complications, particularly intradialytic hypotension prevention.

Application of therapeutic ultrasonic waves across the dialyzer membrane: A pilot study on the impact on dialyzer clearance and safety

INTRODUCTION

Progressive clogging of the dialyzer membrane during hemodialysis can compromise solute removal efficiency. Existing solutions fall short in addressing intradialytic reduction of dialyzer clearance. This pilot study aims to assess the impact and safety of applying therapeutic ultrasonic waves to dialyzers for mitigating intradialytic clogging.

METHODS

In this pilot study, 15 stable maintenance hemodialysis patients (12 males and 3 females) were enrolled. Each patient served as their own control. They underwent one session of hemodialysis with the application of therapeutic ultrasonic waves (Ultrasonic session) and were crossed-over to a second session without the use of ultrasonic waves (Control session). All the study sessions operated at a fixed dialysate flow rate of 500 mL/min and a blood flow rate of 250 or 300 mL/min. The adequacy of dialysis achieved during each session was monitored using Online Clearance Monitoring of the dialysis machines, and clearance K values, varying between 135 and 209 mL/min, were recorded, and plotted. A direct comparison between Control and Ultrasonic sessions was performed to assess the impact and safety of using ultrasonic waves during hemodialysis.

FINDINGS

The mean percentage decline in dialyzer clearance values was 4.41% for Ultrasonic sessions (SD: 5.3) and 12.69% for Control sessions (SD: 6.35) (p-value <0.001). This indicates that the application of ultrasonic waves reduced the decline in clearance values. The mean differences of the blood component parameters were comparable between both Ultrasonic sessions and Control sessions, suggesting the safety of utilizing ultrasonic waves during dialysis. Microscopic membrane analysis corroborated the safety.

DISCUSSION

Intradialytic clogging of dialyzer membranes is a significant problem that can cause dialysis inadequacy. Our study tackles this issue by introducing therapeutic ultrasonic waves to improve dialyzer clearance during hemodialysis sessions in patients.

Greater haemodialysis exposure ('quotidian haemodialysis') has different mortality associations by patient age group

Background

Worldwide, most people requiring kidney replacement therapy receive haemodialysis (HD) three times per week. Greater HD time and/or frequency may improve survival, but implementation requires understanding potential benefits across the range of patients.

Methods

Using data from the Australia and New Zealand Dialysis and Transplant Registry, we assessed whether quotidian HD (defined as >3 sessions/week and/or >5 h/session) was associated with reduced mortality in adult patients. The primary outcome of all-cause mortality was analysed by a time-varying Cox proportional hazards model with quotidian HD as the exposure of interest.

Results

Of 24 138 people who received HD between 2011 and 2019, 2632 (10.9%) received quotidian HD at some stage. These patients were younger, more likely male and more likely to receive HD at home. Overall, quotidian versus standard HD was associated with a decreased risk for all-cause mortality {crude hazard ratio [HR] 0.50 [95% confidence interval (CI) 0.45-0.56]}, but an interaction between quotidian HD and age was identified (P = .005). Stratified by age groups and splitting follow-up time where proportional hazards were violated, the corresponding HR compared with standard HD was 2.43 (95% CI 1.56-3.79) for people >75 years of age in the first year of quotidian HD, 1.52 (95% CI 0.89-2.58) for 1-3 years and 0.95 (95% CI 0.51-1.78) for ≥3 years. There was no significant survival advantage in younger people.

Conclusions

Although quotidian HD conferred survival benefit in crude analyses, people ≥75 years of age had greater mortality with quotidian HD than standard HD. The mortality benefit in younger people was attenuated when adjusted for known confounders.

Active Vitamin D Use and Fractures in Hemodialysis Patients: Results from the International DOPPS

Active vitamin D is commonly used to control secondary hyperparathyroidism in dialysis patients, but it is unknown whether active vitamin D directly improves bone strength, independently of its ability to suppress parathyroid hormone (PTH). We analyzed the association between the prescription of active vitamin D and incidence of any fracture and hip fracture in 41,677 in-center hemodialysis patients from 21 countries in phases 3 to 6 (2005 to 2018) of the Dialysis Outcomes and Practice Patterns Study (DOPPS). We used Cox regression, adjusted for PTH and other potential confounders, and used a per-protocol approach to censor patients at treatment switch during follow-up. We also used a facility preference approach to minimize confounding by indication. Overall, 55% of patients were prescribed active vitamin D at study enrollment. Event rates (per patient-year) were 0.024 for any fracture and 0.010 for hip fracture. The adjusted hazard ratio (95% confidence interval) comparing patients prescribed versus not prescribed active vitamin D was 1.02 (0.90 to 1.17) for any fracture and 1.00 (0.81 to 1.23) for hip fracture. In the facility preference approach, there was no difference in fracture rate between facilities with higher versus lower active vitamin D prescriptions. Thus, our results do not suggest a PTH-independent benefit of active vitamin D in fracture prevention and support the current KDIGO guideline suggesting the use of active vitamin D only in subjects with elevated or rising PTH. Further research is needed to determine the role of active vitamin D beyond PTH control. © 2023 American Society for Bone and Mineral Research (ASBMR).

Experience in Spain with the first patients in home hemodialysis treated with low-flow dialysate monitors

Home hemodialysis (HHD) with low-flow dialysate devices has gained popularity in recent years due to its simple design, portability, and ability to provide greater freedom of movement for our patients. However, there are doubts about the adequacy that this technology offers, since it uses monitors with low-flow bath and lactate. The aim of this study was to demonstrate the clinical benefits of low-flow HHD with the NxStage System One® recently introduced in Spain. We present the results of an observational, retrospective cohort study that included the first patients who started short daily HHD with this device in 12 Spanish centers. We analyzed the evolution of 86 patients at 0, 6 and 12 months, including data related to prescription, and evolution of biochemical parameters related to dialysis dose, anemia, mineral-bone metabolism; evolution of residual renal function, medication usage, and causes of withdrawal during the followup. We were able to demonstrate that this NxStage System One® monitor, in patients with HHD, have provided an adequate dialysis dose, with optimal ultrafiltration rate, with improvement of main biochemical markers of dialysis adequacy. The usage of this technique was associated to a decrease of antihypertensive drugs, phosphate binders and erythropoietin agents, with very good results both patient and technique survival. The simplicity of the technique, together with its good clinical outcomes, should facilitate the growth and utilization of HHD, both in incident and prevalent patients.

Executive summary of the Korean Society of Nephrology 2021 clinical practice guideline for optimal hemodialysis treatment

The Korean Society of Nephrology (KSN) has published a clinical practice guideline (CPG) document for maintenance hemodialysis (HD). The document, 2021 Clinical Practice Guideline on Optimal HD Treatment, is based on an extensive evidence-oriented review of the benefits of preparation, initiation, and maintenance therapy for HD, with the participation of representative experts from the KSN under the methodologists' support for guideline development. It was intended to help clinicians participating in HD treatment make safer and more effective clinical decisions by providing user-friendly guidelines. We hope that this CPG will be meaningful as a recommendation in practice, but not on a regulatory rule basis, as different approaches and treatments may be used by health care providers depending on the individual patient's condition. This CPG consists of eight sections and 15 key questions. Each begins with statements that are graded by the strength of recommendations and quality of the evidence. Each statement is followed by a summary of the evidence supporting the recommendations. There are also a link to full-text documents and lists of the most important reports so that the readers can read further (most of this is available online).

Hidden risks associated with conventional short intermittent hemodialysis: A call for action to mitigate cardiovascular risk and morbidity

The development of maintenance hemodialysis (HD) for end stage kidney disease patients is a success story that continues to save many lives. Nevertheless, intermittent renal replacement therapy is also a source of recurrent stress for patients. Conventional thrice weekly short HD is an imperfect treatment that only partially corrects uremic abnormalities, increases cardiovascular risk, and exacerbates disease burden. Altering cycles of fluid loading associated with cardiac stretching (interdialytic phase) and then fluid unloading (intradialytic phase) likely contribute to cardiac and vascular damage. This unphysiologic treatment profile combined with cyclic disturbances including osmotic and electrolytic shifts may contribute to morbidity in dialysis patients and augment the health burden of treatment. As such, HD patients are exposed to multiple stressors including cardiocirculatory, inflammatory, biologic, hypoxemic, and nutritional. This cascade of events can be termed the dialysis stress storm and sickness syndrome. Mitigating cardiovascular risk and morbidity associated with conventional intermittent HD appears to be a priority for improving patient experience and reducing disease burden. In this in-depth review, we summarize the hidden effects of intermittent HD therapy, and call for action to improve delivered HD and develop treatment schedules that are better tolerated and associated with fewer adverse effects.

High volume online post-dilution hemodiafiltration: how relevant is it in chronic kidney disease?

Online hemodiafiltration is potentially a superior mode of dialysis compared to conventional hemodialysis. However, prospective randomized controlled trials have failed to demonstrate such superiority. Post-hoc analyses of these trials have indicated that high volume post-dilution hemodiafiltration is associated with lower death rates than conventional dialysis. This study discusses whether the lower death rates ascribed to high volume hemodiafiltration are linked to convection volume or the time on dialysis needed to achieve high convection volumes.

Tracing all patients who received insured dialysis treatment in Japan and the present situation of their number of deaths

Background

The survival rate of chronic dialysis patients in Japan remains the highest worldwide, so there is value in presenting Japan’s situation internationally. We examined whether aggregate figures on dialysis patients in the National Database of Health Insurance Claims and Special Health Checkups of Japan (NDB), which contains data on insured procedures of approximately 100 million Japanese residents, complement corresponding figures in the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR).

Methods

Subjects were patients with medical fee points for dialysis recorded in the NDB during 2014–2018. We analyzed annual numbers of dialysis cases, newly initiated dialysis cases– and deaths.

Results

Compared with the JRDR, the NDB had about 6–7% fewer dialysis cases but a similar number of newly initiated dialysis cases. In the NDB, the number of deaths was about 6–10% lower, and the number of hemodialysis cases was lower, while that of peritoneal dialysis cases was higher. The cumulative survival rate at dialysis initiation was approximately 6 percentage points lower in the NDB than in the JRDR, indicating that some patients die at dialysis initiation. Cumulative survival rate by age group was roughly the same between the NDB and JRDR in both sexes.

Conclusion

The use of the NDB enabled us to aggregate data of dialysis patients. With the definition of dialysis patients used in this study, analyses of concomitant medications, comorbidities, surgeries, and therapies will become possible, which will be useful in many future studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-021-02163-z.

Executive Summary of the Korean Society of Nephrology 2021 Clinical Practice Guideline for Optimal Hemodialysis Treatment

The Korean Society of Nephrology (KSN) has published a clinical practice guideline (CPG) document for maintenance hemodialysis (HD). The document, 2021 Clinical Practice Guideline on Optimal HD Treatment, is based on an extensive evidence-oriented review of the benefits of preparation, initiation, and maintenance therapy for HD, with the participation of representative experts from the KSN under the methodologists’ support for guideline development. It was intended to help clinicians participating in HD treatment make safer and more effective clinical decisions by providing user-friendly guidelines. We hope that this CPG will be meaningful as a recommendation in practice, but not on a regulatory rule basis, as different approaches and treatments may be used by health care providers depending on the individual patient’s condition. This CPG consists of eight sections and 15 key questions. Each begins with statements that are graded by the strength of recommendations and quality of the evidence. Each statement is followed by a summary of the evidence supporting the recommendations. There is also a link to full-text documents and lists of the most important reports so that the readers can read further (most of this is available online).

Changes in practice patterns in Japan from before to after JSDT 2013 guidelines on hemodialysis prescriptions: results from the JDOPPS

BACKGROUND

The Japanese Society for Dialysis Therapy (JSDT) published in 2013 inaugural hemodialysis (HD) guidelines. Specific targets include 1.4 for single-pool Kt/V (spKt/V) with a minimum dose of 1.2, minimum dialysis session length of 4 hours, minimum blood flow rate (BFR) of 200 mL/min, fluid removal rate no more than 15 mL/kg/hr, and hemodiafiltration (HDF) therapy for certain identified symptoms. We evaluated the effect of these guidelines on actual practice in the years spanning 2005 - 2018.

METHODS

Analyses were carried out to describe trends in the above HD prescription practices from December 2005 to April 2013 (before guideline publication) to August 2018 based on prevalent patient cross-sections from approximately 60 randomly selected HD facilities participating in the Japan Dialysis Outcomes and Practice Patterns Study.

RESULTS

From April 2006 to August 2017 continual rises occurred in mean spKt/V (from 1.35 to 1.49), and percent of patients having spKt/V>1.2 (71% to 85%). Mean BFR increased with time from 198.3 mL/min (April 2006) to 218.4 mL/min (August 2017) , along with percent of patients with BFR >200 ml/min (65% to 85%). HDF use increased slightly from 6% (April 2006 and August 2009) to 8% by April 2013, but increased greatly thereafter to 23% by August 2017. In contrast, mean HD treatment time showed little change from 2006-2017, whereas mean UFR declined from 11.3 in 2006 to 8.4 mL/Kg/hour in 2017.

CONCLUSIONS

From 2006 - 2018 Japanese HD patients experienced marked improvement in reaching the spKt/V target specified by the 2013 JSDT guidelines. This may have been due to moderate increase in mean BFR even though mean HD session length did not change much. In addition, HDF use increased dramatically in this time period. Other HD delivery changes during this time, such as increased use of super high flux dialyzers, also merit study. While we cannot definitively conclude a causal relationship between the publication of the guidelines and the subsequent practice changes in Japan, those changes moved practice closer to the recommendations of the guidelines.

Improvements in six aspects of quality of care of incident hemodialysis patients - a real-world experience

Background

The transition from chronic kidney disease stage 5 to initiation of hemodialysis has gained increased attention in recent years as this period is one of high risk for patients with an annual mortality rate exceeding 20%. Morbidity and mortality in incident hemodialysis patients are partially attributed to failure to attain guideline-based targets. This study focuses on improvements in six aspects of quality of dialysis care (adequacy, anemia, nutrition, chronic kidney disease-mineral bone disorder (CKD-MBD), blood pressure and vascular access) aligning with KDIGO guidelines, during the first 6 months of hemodialysis.

Methods

We analyzed patient demographics, practice patterns and laboratory data in all 3 462 patients (mean age 65.9 years, 41% females) on hemodialysis (incident <90 days on hemodialysis, n=603, prevalent ≥90 days on hemodialysis, mean 55 months, n=2 859) from all 56 DaVita centers in Poland (51 centers) and Portugal (5 centers). 80% of patients had hemodialysis and 20% hemodiafiltration. Statistical analyses included unpaired and paired Students t-test, Chi-2 analyses, McNemar test and logistic regression analysis.

Results

Incident patients had lower Kt/V (1.4 vs 1.7, p<0.001), lower serum albumin (37 vs 40 g/l, p=0.001), lower Hb (9.9 vs 11.0 g/dl, p<0.001), lower TSAT (26 vs 31%, p<0.001), lower iPTH (372 vs 496 pg/ml, p<0.001), more often a central venous catheter (68 vs 26%, p<0.001), less often an AV fistula (34 vs 70 %, p<0.001) compared with all prevalent patients. Significantly more prevalent patients achieved international treatment targets.

Improvements in quality of care was also analyzed in a subgroup of 258 incident patients who were followed prospectively for 6 months. We observed significant improvements in Kt/V (p<0.001), albumin (p<0.001), Hb (p<0.001) transferrin saturation (TSAT, p<0.001), iPTH (p=0.005) and an increased use of AV fistula (p<0.001). Furthermore, logistic regression analyses identified treatment time and TSAT as major factors influencing the attainment of adequacy and anemia treatment targets.

Conclusion

This large real-world European multicenter analysis of representative incident hemodialysis patients indicates that the use of medical protocols and medical targets assures significant improvements in quality of care, which may correspond to better outcomes. A selection bias of survivors with less comorbidities in prevalent patients may have influenced the results.

Evaluating the clinical experience of a regional in-center nocturnal hemodialysis program: The patient and staff perspective

INTRODUCTION

End-stage kidney disease causes significant morbidity, mortality, and reduced quality of life. Despite improvements in conventional hemodialysis, these problems persist. In-center nocturnal hemodialysis (INHD) has been shown to be beneficial in observational studies. This report outlines a 4-year renal network experience of INHD from the patient and frontline staff perspective.

METHODS

Staff and patients' experiences of INHD were evaluated through two work streams. Work stream one: 12 patients who chose to stop INHD and 24 patients who chose to continue with INHD completed an anonymous survey. Work stream two: one-to-one interviews with 20 patients receiving INHD and seven staff working INHD shifts were conducted. Clinical incident reporting for conventional hemodialysis and INHD from April 2014 to December 2018 was reviewed.

FINDINGS

Work stream one: Five themes were identified; facilities, time, health and well-being, sleep, and transport. A patient "starter pack" was developed and improvements to the dialysis unit were completed. Work stream two: Patient interviews demonstrated starter packs to aid sleep were well received; sleep itself was not a single reason to discontinue INHD. Staff indicated that their greatest concern was staffing levels; although staff-to-patient ratio remains unchanged, total numbers on INHD shifts were fewer, causing concern around less colleague availability for support during an emergency.

SAFETY

363 clinical incidents were reported across all dialysis shifts; for conventional hemodialysis, a larger proportion were due to medical interventions, infection control, and transport; for INHD, most incidents centered around communication with patients and relatives, delays in patient transfer, and issues with medical equipment or facilities.

DISCUSSION

Patients continue with INHD due to increased social time and perceived health benefits. Patient starter packs and adjustments to the dialysis unit may enhance sleep. This experience has optimized the design of the NightLife study; a randomized controlled trial evaluated the effect of INHD on quality of life.

Blood flow rate: An independent risk factor of mortality in Chinese hemodialysis patients

BACKGROUND

Studies suggested the association between blood flow rate (BFR) and mortality might be beyond dialysis adequacy. This study aimed to explore if BFR is an independent predictor of clinical outcomes in Chinese hemodialysis (HD) patients.

METHODS

This study included data from patients in China Dialysis Outcomes and Practice Patterns Study (DOPPS) Phase 5. Patients with a record of BFR were included, and demographic data, comorbidities, hospitalization, and death records were collected. Associations between BFR and all-cause mortality and hospitalization were analyzed using Cox regression models.

RESULTS

One thousand four hundred twelve (98.9%) patients were included. Most patients were with BFR < 300 ml/min. After full adjustment, each 10-ml/min increase of BFR was associated with a 6.4% decrease in all-cause mortality risk (HR: 0.936, 95% CI: 0.880-0.996) but not first hospitalization (HR: 0.987, 95% CI: 0.949-1.027). The impact of BFR on mortality may be more prominent in patients who were male gender, nondiabetic, albumin < 4.0 g/dl, and hemoglobin ≥ 9.0 g/dl.

CONCLUSION

Increased BFR is independently associated with a lower risk of all-cause mortality within the range of BFR 200-300 ml/min. And this effect is more pronounced in patients who were male gender, nondiabetic, albumin < 4.0 g/dl, and hemoglobin ≥ 9.0 g/dl.

Experience in Spain with the first patients in home hemodialysis treated with low-flow dialysate monitors

Home hemodialysis (HHD) with low-flow dialysate devices has gained popularity in recent years due to its simple design, portability, and ability to provide greater freedom of movement for our patients. However, there are doubts about the adequacy that this technology offers, since it uses monitors with low-flow bath and lactate. The aim of this study was to demonstrate the clinical benefits of low-flow HHD with the NxStage System One® recently introduced in Spain. We present the results of an observational, retrospective cohort study that included the first patients who started short daily HHD with this device in 12 Spanish centers. We analyzed the evolution of 86 patients at 0, 6 and 12 months, including data related to prescription, and evolution of biochemical parameters related to dialysis dose, anemia, mineral-bone metabolism; evolution of residual renal function, medication usage, and causes of withdrawal during the followup. We were able to demonstrate that this NxStage System One® monitor, in patients with HHD, have provided an adequate dialysis dose, with optimal ultrafiltration rate, with improvement of main biochemical markers of dialysis adequacy. The usage of this technique was associated to a decrease of antihypertensive drugs, phosphate binders and erythropoietin agents, with very good results both patient and technique survival. The simplicity of the technique, together with its good clinical outcomes, should facilitate the growth and utilization of HHD, both in incident and prevalent patients.

Clinical epidemiological analysis of cohort studies investigating the pathogenesis of kidney disease

In recent years, large cohort studies of patients with chronic kidney disease (CKD) have been established all over the world. These studies have attempted to analyze the pathogenesis of CKD using a large body of published evidence. The design of cohort studies is characterized by the measurement of the exposure prior to the occurrence of the outcome, which has the advantage of clarifying the temporal relationship between predictors and outcomes and estimating the strength of the causal relationship between predictors and multiple outcomes. Recent advances in biostatistical analysis methods, such as propensity scores and risk prediction models, are facilitating causal inference using higher quality evidence with greater precision in observational studies. In this review, we will discuss clinical epidemiological research of kidney disease based on the analysis of observational cohort data sets, with a focus on our previous studies.

Influence of Tunneled Hemodialysis-Catheters on Inflammation and Mortality in Dialyzed Patients

Older age and comorbidities in hemodialysis patients determines the use of tunneled catheters as vascular access despite their reported clinical and mortality disadvantages. This prospective matched study analyzes the impact of permanent catheters on inflammation and mortality in hemodialysis patients; We studied 108 patients, 54 with AV-fistula (AVF) and 54 with indwelling hemodialysis catheters (HDC) matched by sex, age, diabetes and time under renal-replacement therapy comparing dialysis efficacy, inflammation and micro-inflammation parameters as well as mortality. Cox-regression analysis was applied to determine predictors of mortality, HDC patients presented higher C-reactive-protein (CRP) blood levels and percentage of pro-inflammatory lymphocytes CD14+/CD16+ with worse dialysis-efficacy parameters. Thirty-six-months mortality appeared higher in the HDC group although statistical significance was not reached. Age with a Hazard Ratio (HR) = 1.06, hypoalbuminemia (HR = 0.43), hypophosphatemia (HR = 0.75) and the increase in CD14+/CD16+ monocyte count (HR = 1.02) were predictors of mortality; elder patients dialyzing through HDC show increased inflammation parameters as compared with nAVF bearing patients, although they do not present a significant increase in mortality when matched by covariates. Increasing age and percentage of pro-inflammatory monocytes as well as decreased phosphate and serum-albumin were predictors of mortality and indicate the main conclusions or interpretations.

Effect of increased blood flow rate on renal anemia and hepcidin concentration in hemodialysis patients

Background

Increasing the blood flow rate (BFR) is a useful method for increasing Kt/V and the clearance for low molecular solutes. Hemodialysis patients are often anemic due to hypoerythropoiesis and their chronic inflammatory state. Hepcidin, a hormone that regulates iron homeostasis, is considered as an indicator of iron deficiency in patients with end-stage renal disease. This study aimed to investigate the effects of an increased BFR during hemodialysis on serum hepcidin levels and anemia.

Methods

Between April 2014 and March 2016, 22 chronic dialysis patients (11 men [50.0 %]; mean [± standard deviation] age, 72 ± 12 years) undergoing maintenance hemodialysis treatment, thrice weekly, were enrolled and followed prospectively for 24 months. In April 2014, the BFR was 200 mL/min; in April 2015 this was increased to 400 mL/min, which was within acceptable limits. The dialysate flow rate remained stable at; 500mlL/min. Blood samples were collected in March 2015 and 2016. The primary endpoint was the comparison of the amounts of erythropoiesis-stimulating agent (ESA) required.

Results

The increased BFR increased the Kt/V and contributed to significantly decreased urea nitrogen (UN) (p = 0.015) and creatinine (Cr) (p = 0.005) levels. The dialysis efficiency was improved by increasing the BFR. Ferritin (p = 0.038), hepcidin (p = 0.041) and high-sensitivity interleukin-6 (p = 0.038) levels were also significantly reduced. The ESA administered was significantly reduced (p = 0.004) and the Erythropoietin Resistant Index (ERI) significantly improved (p = 0.031). The reduction rates in UN (p < 0.001), Cr (p < 0.001), and beta-2 microglobulin (p = 0.017) levels were significantly greater post the BFR increase compared to those prior to the BFR increase. However, hepcidin was not affected by the BFR change.

Conclusions

Increasing BFR was associated with hemodialysis efficiency, and led to reduce inflammatory cytokine interleukin-6, but did not contribute to reduce C-reactive protein. This reduced hepcidin levels, ESA dosage and ERI. Hepcidin levels were significantly correlated with ferritin levels, and it remains to be seen whether reducing hepcidin leads to improve ESA and iron availability during anemia management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02426-7.

N-terminal pro brain natriuretic peptide predicts both all-cause and cardiovascular disease mortality in Japanese hemodialysis patients

BACKGROUND

The association between N-terminal pro brain natriuretic peptide (NT-proBNP) level and long-term mortality in Japanese hemodialysis patients has not been fully assessed.

METHODS

This prospective, multicenter study included 1428 hemodialysis outpatients. Baseline NT-proBNP levels were measured at the first hemodialysis session of the week and participants were followed for 5 years. The areas under the curve were calculated from receiver operating characteristic curves. Groups determined by quartiles of baseline NT-proBNP level were assessed by the Kaplan-Meier method and log-rank test. The association between NT-proBNP level and mortality was assessed using multivariate Cox proportional hazards models.

RESULTS

During the 5-year follow-up, we observed 370 deaths and 256 censored cases. The areas under the curve of pre-hemodialysis NT-proBNP for all-cause mortality and cardiovascular disease mortality after 1 year were 0.75 and 0.78, respectively, and significantly greater than the areas under the curve at the 3- and 5-year follow-up. Cut-off values for all-cause mortality and cardiovascular disease mortality after 1 year were 4550 and 5467 ng/L, respectively (sensitivity: 82% and 81%; specificity: 59% and 64%). Kaplan-Meier survival analysis showed that the group with pre-hemodialysis NT-proBNP ≥ 8805 ng/L had increased all-cause mortality (P < 0.001) and cardiovascular disease mortality (P < 0.001). Finally, multivariate Cox analysis showed that NT-proBNP level was associated with all-cause mortality (P < 0.001) and cardiovascular disease mortality (P = 0.004) independently from other clinical parameters.

CONCLUSION

NT-proBNP is a useful marker to predict both all-cause and cardiovascular disease mortality in hemodialysis patients.

Anemia management for home dialysis including the new US public policy initiative

Patients with end-stage kidney disease (ESKD) requiring kidney replacement therapy are often treated in conventional dialysis centers at substantial cost and patient inconvenience. The recent United States Executive Order on Advancing American Kidney Health, in addition to focusing on ESKD prevention and reforming the kidney transplantation system, focuses on providing financial incentives to promote a shift toward home dialysis. In accordance with this order, a goal was set to have 80% of incident dialysis patients receiving home dialysis or a kidney transplant by 2025. Compared with conventional in-center therapy, home dialysis modalities, including both home hemodialysis and peritoneal dialysis, appear to offer equivalent or improved mortality, clinical outcomes, hospitalization rates, and quality of life in patients with ESKD in addition to greater convenience, flexibility, and cost-effectiveness. Treatment of anemia, a common complication of chronic kidney disease, may be easier to manage at home with a new class of agents, hypoxia-inducible factor-prolyl hydroxylase inhibitors, which are orally administered in contrast to the current standard of care of i.v. iron and/or erythropoiesis-stimulating agents. This review evaluates the clinical, quality-of-life, economic, and social aspects of dialysis modalities in patients with ESKD, including during the coronavirus disease 2019 pandemic; explores new therapeutics for the management of anemia in chronic kidney disease; and highlights how the proposed changes in Advancing American Kidney Health provide an opportunity to improve kidney health in the United States.

Global Epidemiology of End-Stage Kidney Disease and Disparities in Kidney Replacement Therapy

BACKGROUND

The global epidemiology of end-stage kidney disease (ESKD) reflects each nation's unique genetic, environmental, lifestyle, and sociodemographic characteristics. The response to ESKD, particularly regarding kidney replacement therapy (KRT), depends on local disease burden, culture, and socioeconomics. Here, we explore geographic variation and global trends in ESKD incidence and prevalence and examine variations in KRT modality, practice patterns, and mortality. We conclude with a discussion on disparities in access to KRT and strategies to reduce ESKD global burden and to improve access to treatment in low- and middle-income countries (LMICs).

SUMMARY

From 2003 to 2016, incidence rates of treated ESKD were relatively stable in many higher income countries but rose substantially predominantly in East and Southeast Asia. The prevalence of treated ESKD has increased worldwide, likely due to improving ESKD survival, population demographic shifts, higher prevalence of ESKD risk factors, and increasing KRT access in countries with growing economies. Unadjusted 5-year survival of ESKD patients on KRT was 41% in the USA, 48% in Europe, and 60% in Japan. Dialysis is the predominant KRT in most countries, with hemodialysis being the most common modality. Variations in dialysis practice patterns account for some of the differences in survival outcomes globally. Worldwide, there is a greater prevalence of KRT at higher income levels, and the number of people who die prematurely because of lack of KRT access is estimated at up to 3 times higher than the number who receive treatment. Key Messages: Many people worldwide in need of KRT as a life-sustaining treatment do not receive it, mostly in LMICs where health care resources are severely limited. This large treatment gap demands a focus on population-based prevention strategies and development of affordable and cost-effective KRT. Achieving global equity in KRT access will require concerted efforts in advocating effective public policy, health care delivery, workforce capacity, education, research, and support from the government, private sector, nongovernmental, and professional organizations.

Kt/V: achievement, predictors and relationship to mortality in hemodialysis patients in the Gulf Cooperation Council countries: results from DOPPS (2012-18)

BACKGROUND

Dialysis adequacy, as measured by single pool Kt/V, is an important parameter for assessing hemodialysis (HD) patients' health. Guidelines have recommended Kt/V of 1.2 as the minimum dose for thrice-weekly HD. We describe Kt/V achievement, its predictors and its relationship with mortality in the Gulf Cooperation Council (GCC) (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates).

METHODS

We analyzed data (2012-18) from the prospective cohort Dialysis Outcomes and Practice Patterns Study for 1544 GCC patients ≥18 years old and on dialysis >180 days.

RESULTS

Thirty-four percent of GCC HD patients had low Kt/V (<1.2) versus 5%-17% in Canada, Europe, Japan and the USA. Across the GCC countries, low Kt/V prevalence ranged from 10% to 54%. In multivariable logistic regression, low Kt/V was more common (P < 0.05) with larger body weight and height, being male, shorter treatment time (TT), lower blood flow rate (BFR), greater comorbidity burden and using HD versus hemodiafiltration. In adjusted Cox models, low Kt/V was strongly related to higher mortality in women [hazard ratio (HR) = 1.91, 95% confidence interval (CI) 1.09-3.34] but not in men (HR = 1.16, 95% CI 0.70-1.92). Low BFR (<350 mL/min) and TT (<4 h) were common; 41% of low Kt/V cases were attributable to low BFR or TT (52% for women and 36% for men).

CONCLUSION

Relatively large proportions of GCC HD patients have low Kt/V. Increasing BFR to ≥350 mL/min and TT to ≥4 h thrice weekly will reduce low Kt/V prevalence and may improve survival in GCC HD patients-particularly among women.

The real-world effectiveness of sucroferric oxyhydroxide in European hemodialysis patients: a 1-year retrospective database analysis

BACKGROUND

The iron-based phosphate binder (PB), sucroferric oxyhydroxide (SFOH), demonstrated its effectiveness for lowering serum phosphate levels, with low daily pill burden, in clinical trials of dialysis patients with hyperphosphatemia. This retrospective database analysis evaluated the real-world effectiveness of SFOH for controlling serum phosphate in European hemodialysis patients.

METHODS

De-identified patient data were extracted from a clinical database (EuCliD®) for adult hemodialysis patients from France, Italy, Portugal, Russia and Spain who were newly prescribed SFOH for up to 1 year as part of routine clinical care. Serum phosphate and pill burden were compared between baseline (3-month period before starting SFOH) and four consecutive quarterly periods of SFOH therapy (Q1-Q4; 12 months) in the overall cohort and three subgroups: PB-naïve patients treated with SFOH monotherapy (mSFOH), and PB-pretreated patients who were either switched to SFOH monotherapy (PB → mSFOH), or received SFOH in addition to another PB (PB + SFOH).

RESULTS

1096 hemodialysis patients (mean age: 60.6 years; 65.8% male) were analyzed, including 796, 188 and 53 patients in, respectively, the PB + SFOH, mSFOH, and PB → mSFOH groups. In the overall cohort, serum phosphate decreased significantly from 1.88 mmol/L at baseline to 1.77-1.69 mmol/L during Q1-Q4, and the proportion of patients achieving serum phosphate ≤1.78 mmol/L increased from 41.3% at baseline to 56.2-62.7% during SFOH treatment. Mean PB pill burden decreased from 6.3 pills/day at baseline to 5.0-5.3 pills/day during Q1-Q4. The subgroup analysis found the proportion of patients achieving serum phosphate ≤1.78 mmol/L increased significantly from baseline during SFOH treatment in the PB + SFOH group (from 38.1% up to 60.9% [Q2]) and the mSFOH group (from 49.5% up to 75.2% [Q2]), but there were no significant changes in the PB → mSFOH group. For the PB + SFOH group, serum phosphate reductions were achieved with a similar number of PB pills prescribed at baseline prior to SFOH treatment (6.5 vs 6.2 pills/day at Q4). SFOH daily pill burden was low across all 3 subgroups (2.1-2.8 pills/day).

CONCLUSION

In this real-world study of European hemodialysis patients, prescription of SFOH as monotherapy to PB-naïve patients, or in addition to existing PB therapy, was associated with significant improvements in serum phosphate control and a low daily pill burden.

Evaluation of Dialysis Water Quality at Hospitals in Baghdad, Iraq

BACKGROUND

Dialysis water quality is one of the most important factors for ensuring the safe and effective delivery of hemodialysis. It has been known for over a decade that there might be hazardous contaminants in the water and concentrates used to prepare dialysis fluid. Rigorous international standards for the purification of dialysis fluids have been established, which were used in the present study to compare the quality of dialysis water as there is no national standard for dialysis water quality in Iraq.

OBJECTIVES

There are more than 20 dialysis centers in Iraq, most of which contain similar units for the processing of dialysis water. The present study evaluated the quality of water used for dialysis in four dialysis centers located within Baghdad hospitals.

METHODS

Physical and chemical tests were carried out in the laboratory after sampling water from each dialysis center. Water samples were collected from three locations in each dialysis center. Hospital municipal water samples were collected from the tanks feeding dialysis units; samples of dialysis water were collected from the dialysis water treatment unit outlets; and samples of dialysis water were collected from the distribution network in dialysis rooms.

RESULTS

The results showed a fluctuation in the quality of the dialysis water (dialysis water and water from the dialysis distribution network), indicating that it is unacceptable compared to international standards. Chemical analysis showed that 75% of the dialysis water had elevated aluminum concentrations. Chemical analysis also found that dialysis water had elevated concentrations of free residual chlorine at some dialysis centers.

CONCLUSIONS

All hemodialysis centers need careful monitoring and preventive maintenance to ensure good water quality. In addition, it is important to revise the design of the water treatment units according to water quality.

COMPETING INTERESTS

The authors declare no competing financial interests.

Dialysis-Induced Cardiovascular and Multiorgan Morbidity

Hemodialysis has saved many lives, albeit with significant residual mortality. Although poor outcomes may reflect advanced age and comorbid conditions, hemodialysis per se may harm patients, contributing to morbidity and perhaps mortality. Systemic circulatory "stress" resulting from hemodialysis treatment schedule may act as a disease modifier, resulting in a multiorgan injury superimposed on preexistent comorbidities. New functional intradialytic imaging (i.e., echocardiography, cardiac magnetic resonance imaging [MRI]) and kinetic of specific cardiac biomarkers (i.e., Troponin I) have clearly documented this additional source of end-organ damage. In this context, several factors resulting from patient-hemodialysis interaction and/or patient management have been identified. Intradialytic hypovolemia, hypotensive episodes, hypoxemia, solutes, and electrolyte fluxes as well as cardiac arrhythmias are among the contributing factors to systemic circulatory stress that are induced by hemodialysis. Additionally, these factors contribute to patients' symptom burden, impair cognitive function, and finally have a negative impact on patients' perception and quality of life. In this review, we summarize the adverse systemic effects of current intermittent hemodialysis therapy, their pathophysiologic consequences, review the evidence for interventions that are cardioprotective, and explore new approaches that may further reduce the systemic burden of hemodialysis. These include improved biocompatible materials, smart dialysis machines that automatically may control the fluxes of solutes and electrolytes, volume and hemodynamic control, health trackers, and potentially disruptive technologies facilitating a more personalized medicine approach.

Variability and trends over time and across centres in haemodialysis weekly duration in Australia and New Zealand

AIM

Haemodialysis treatment prescription varies widely internationally. This study explored patient- and centre-level characteristics associated with weekly haemodialysis hours.

METHODS

Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry data were analysed. Characteristics associated with weekly duration were evaluated using mixed-effects linear regression models with patient- and centre-level covariates as fixed effects, and dialysis centre and state as random effects using the 2017 prevalent in-centre haemodialysis (ICHD) and home haemodialysis (HHD) cohorts. Evaluation of patterns of weekly duration over time analysed the 2000 to 2017 incident ICHD and HHD cohorts.

RESULTS

Overall, 12 494 ICHD and 1493 HHD prevalent patients in 2017 were included. Median weekly treatment duration was 13.5 (interquartile range [IQR] 12-15) hours for ICHD and 16 (IQR 15-20) hours for HHD. Male sex, younger age, higher body mass index, arteriovenous fistula/graft use, Aboriginal and Torres Strait Islander ethnicity and longer dialysis vintage were associated with longer weekly duration for both ICHD and HHD. No centre characteristics were associated with duration. Variability in duration across centres was very limited in ICHD compared with HHD, with variation in HHD being associated with state. Duration did not vary significantly over time for ICHD, whereas longer weekly HHD treatments were reported between 2006 and 2012 compared with before and after this period.

CONCLUSION

This study in the Australian and New Zealand haemodialysis population showed that weekly duration was primarily associated with patient characteristics. No centre effect was demonstrated. Practice patterns seemed to differ across states/countries, with more variability in HHD than ICHD.

Understanding Development of Malnutrition in Hemodialysis Patients: A Narrative Review

Hemodialysis (HD) majorly represents the global treatment option for patients with chronic kidney disease stage 5, and, despite advances in dialysis technology, these patients face a high risk of morbidity and mortality from malnutrition. We aimed to provide a novel view that malnutrition susceptibility in the global HD community is either or both of iatrogenic and of non-iatrogenic origins. This categorization of malnutrition origin clearly describes the role of each factor in contributing to malnutrition. Low dialysis adequacy resulting in uremia and metabolic acidosis and dialysis membranes and techniques, which incur greater amino-acid losses, are identified modifiable iatrogenic factors of malnutrition. Dietary inadequacy as per suboptimal energy and protein intakes due to poor appetite status, low diet quality, high diet monotony index, and/or psychosocial and financial barriers are modifiable non-iatrogenic factors implicated in malnutrition in these patients. These factors should be included in a comprehensive nutritional assessment for malnutrition risk. Leveraging the point of origin of malnutrition in dialysis patients is crucial for healthcare practitioners to enable personalized patient care, as well as determine country-specific malnutrition treatment strategies.

Survival of patients treated with extended-hours haemodialysis in Europe: an analysis of the ERA-EDTA Registry

Background

Previous US studies have indicated that haemodialysis with ≥6-h sessions [extended-hours haemodialysis (EHD)] may improve patient survival. However, patient characteristics and treatment practices vary between the USA and Europe. We therefore investigated the effect of EHD three times weekly on survival compared with conventional haemodialysis (CHD) among European patients.

Methods

We included patients who were treated with haemodialysis between 2010 and 2017 from eight countries providing data to the European Renal Association–European Dialysis and Transplant Association Registry. Haemodialysis session duration and frequency were recorded once every year or at every change of haemodialysis prescription and were categorized into three groups: CHD (three times weekly, 3.5–4 h/treatment), EHD (three times weekly, ≥6 h/treatment) or other. In the primary analyses we attributed death to the treatment at the time of death and in secondary analyses to EHD if ever initiated. We compared mortality risk for EHD to CHD with causal inference from marginal structural models, using Cox proportional hazards models weighted for the inverse probability of treatment and censoring and adjusted for potential confounders.

Results

From a total of 142 460 patients, 1338 patients were ever treated with EHD (three times, 7.1 ± 0.8 h/week) and 89 819 patients were treated exclusively with CHD (three times, 3.9 ± 0.2 h/week). Crude mortality rates were 6.0 and 13.5/100 person-years. In the primary analyses, patients treated with EHD had an adjusted hazard ratio (HR) of 0.73 [95% confidence interval (CI) 0.62–0.85] compared with patients treated with CHD. When we attributed all deaths to EHD after initiation, the HR for EHD was comparable to the primary analyses [HR 0.80 (95% CI 0.71–0.90)].

Conclusions

EHD is associated with better survival in European patients treated with haemodialysis three times weekly.

Assessment of microbial contamination levels of water in hemodialysis centers in Baghdad, Iraq

Monitoring water quality in hemodialysis systems is extremely important to maintain adequate quality services for patients suffering from kidney failure. This work aims to examine and evaluate bacteriological characteristics and endotoxin contamination levels in hemodialysis water produced in dialysis centers. Forty-eight water samples were collected and analyzed from four major hospitals in Baghdad for one year to evaluate seasonal effects. The analysis included the determination of total heterotrophic bacteria using the pour plate method, identification of bacterial isolate using the Vitek2 compact instrument, and the determination of endotoxins levels using Limulus amebocyte lysate (LAL) method. In addition, tap water samples (a source for the hemodialysis water) were also examined bacteriologically. Results showed that 44% of the tested samples for bacterial levels are higher than the maximum value of (100 CFU/ml) set out by the international standards. Endotoxin values for these centers fluctuated during the study period, and 44% of them exceeded the international standards (>0.25 EU/ml). These results call for applying improved technology to modify the existing water treatment units for better control and for national standardization of the microbiological quality of hemodialysis water. PRACTITIONER POINTS: Four hemodialysis centers were assessed by measuring the bacteriological and endotoxins levels of their feed and product water. Product water showed elevated levels of bacteria that exceeded the international guideline value of 100 CFU/ml. Most of the identified bacterial species were Gram-negative that arise the possibility of contributing to endotoxin generation. Product water showed fluctuated values of endotoxins. About 44% of the measured samples were higher than the international guideline values of 0.25 EU/ml.

No evidence of a legacy effect on survival following randomization to extended hours dialysis in the ACTIVE Dialysis trial

AIM

Extended hours haemodialysis is associated with superior survival to standard hours. However, residual confounding limits the interpretation of this observation. We aimed to determine the effect of a period of extended hours dialysis on long-term survival among participants in the ACTIVE Dialysis trial.

METHODS

Two-hundred maintenance haemodialysis recipients were randomized to extended hours dialysis (median 24 h/wk) or standard hours dialysis (median 12 h/wk) for 12 months. Further pre-specified observational follow up occurred at 24, 36 and 60 months. Vital status and modality of renal replacement therapy were ascertained.

RESULTS

Over the 5 years, 38 participants died, 30 received a renal transplant, and 6 were lost to follow up. Total weekly dialysis hours did not differ between standard and extended groups during the follow-up period (14.1 hours [95%CI 13.4-14.8] vs 14.8 hours [95%CI 14.1-15.6]; P = .16). There was no difference in all-cause mortality (hazard ratio for extended hours 0.91 [95%CI 0.48-1.72]; P = .77). Similar results were obtained after censoring participants at transplantation, and after adjusting for potential confounding variables. Subgroup analysis did not reveal differences in treatment effect by region, dialysis setting or vintage (P-interaction .51, .54, .12, respectively).

CONCLUSION

Twelve months of extended hours dialysis did not improve long-term survival nor affect dialysis hours after the intervention period. An urgent need remains to further define the optimal dialysis intensity across the broad range of dialysis recipients.

Data from the ERA-EDTA Registry were examined for trends in excess mortality in European adults on kidney replacement therapy

The objective of this study was to investigate whether the improvement in survival seen in patients on kidney replacement therapy reflects the enhanced survival of the general population. Patient and general population statistics were obtained from the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry and the World Health Organization databases, respectively. Relative survival models were composed to examine trends over time in all-cause and cause-specific excess mortality, stratified by age and modality of kidney replacement therapy, and adjusted for sex, primary kidney disease and country. In total, 280,075 adult patients started kidney replacement therapy between 2002 and 2015. The excess mortality risk in these patients decreased by 16% per five years (relative excess mortality risk (RER) 0.84; 95% confidence interval 0.83-0.84). This reflected a 14% risk reduction in dialysis patients (RER 0.86; 0.85-0.86), and a 16% increase in kidney transplant recipients (RER 1.16; 1.07-1.26). Patients on dialysis showed a decrease in excess mortality risk of 28% per five years for atheromatous cardiovascular disease as the cause of death (RER 0.72; 0.70-0.74), 10% for non-atheromatous cardiovascular disease (RER 0.90; 0.88-0.92) and 10% for infections (RER 0.90; 0.87-0.92). Kidney transplant recipients showed stable excess mortality risks for most causes of death, although it did worsen in some subgroups. Thus, the increase in survival in patients on kidney replacement therapy is not only due to enhanced survival in the general population, but also due to improved survival in the patient population, primarily in dialysis patients.

The association between longer haemodialysis treatment times and hospitalization and mortality after the two-day break in individuals receiving three times a week haemodialysis

BACKGROUND

On the first haemodialysis (HD) day after the 2-day break in three times a week (3×W) in-centre HD, mortality and hospitalization are higher. If longer HD sessions prescribed 3×W is associated with a reduction in these events is unknown.

METHODS

HD session length in 19 557 prevalent European in-centre 3×W HD patients participating in the Dialysis Outcomes and Practice Patterns Study (1998-2011) were categorized into <200, 200-225, 226-250 or >250 min. Standardized event rates on the first (HD1) versus the second (HD2) HD day after the 2-day break, with supporting Cox proportional hazards models adjusted for patient and dialysis characteristics, were generated for all-cause mortality, all-cause hospitalization, out-of-hospital death and fluid overload hospitalization.

RESULTS

By comparing HD1 with HD2, increased rates of all endpoints were observed (all P < 0.002). As HD session lengthened across the four groups, all-cause mortality per 100 patient-years on the HD1 (23.0, 20.4, 16.4 and 14.6) and HD2 (26.1, 13.3, 13.4 and 12.1) reduced. Similar improvements were observed for out-of-hospital death but were less marked for hospitalization endpoints. However, even patients dialysing >250 min were at significantly greater risk on HD1 when compared with their HD2 for out-of-hospital death [hazard ratio (HR) = 2.1, 95% CI 1.0-4.3], all-cause hospitalization (HR = 1.3, 95% CI 1.2-1.4) and fluid overload hospitalization (HR = 3.2, 95% CI 1.8-6.0).

CONCLUSIONS

Despite the association between reduced mortality across all dialysis days in patients performing longer sessions, elevated risk on the first dialysis day relative to the second persists even in patients dialysing 4.5 h 3×W.

Successful cadaveric kidney transplantation in an extended-hours hemodialysis patient with long-term hemodialysis vintage for 297 months

The patient was a 41-year-old male who had been maintained on extended-hours hemodialysis for 297 months. Despite of long-term hemodialysis vintage, he had no vascular calcification and ectopic calcification. His kidney graft did not experience rejection or other complications 18 months after the cadaveric kidney transplant. Previous reports indicated that graft survival of extended-hours hemodialysis patients did not differ from conventional hemodialysis. However, the dialysis periods in these reports were much shorter than our case. Therefore, extended-hours hemodialysis in long-term dialysis patients may improve renal transplant outcomes in the countries where the waiting time for kidney transplant is long.

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We succeeded in kidney transplantation of extended-hours hemodialysis patient with long-term hemodialysis vintage.

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Long-term hemodialysis vintage is known to cause vascular calcification and to decrease graft survival.

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Extended-hours hemodialysis in long-term dialysis patients may improve renal transplant outcome.

Perioperative outcomes and risk assessment in dialysis patients: current knowledge and future directions

Perioperative medicine is rapidly emerging as a key discipline to address the specific needs of high-risk surgical groups, such as those on chronic dialysis. Crude hospital separation rates for chronic dialysis patients are considerably higher than patients with normal renal function, with up to 15% of admission being related to surgical intervention. Dialysis dependency carries substantial mortality and morbidity risk compared to patients with normal renal function. This group of patients has a high comorbid burden and complex medical need, making accurate perioperative planning essential. Existing perioperative risk assessment tools are unvalidated in chronic dialysis patients. Furthermore, they fail to incorporate important dialysis treatment-related characteristics that could potentially influence perioperative outcomes. There is a dearth of information on perioperative outcomes of Australasian dialysis patients. Current perioperative outcome estimates stem predominantly from North American literature; however, the generalisability of these findings is limited, as the survival of North American dialysis patients is significantly inferior to their Australasian counterparts and potentially confounds reported perioperative outcomes; let alone regional variation in surgical indication and technique. We propose that data linkage between high-quality national registries will provide more complete data with more detailed patient and procedural information to allow for more informative analyses to develop and validate dialysis-specific risk assessment tools.

Renal Association Clinical Practice Guideline on Haemodialysis

This guideline is written primarily for doctors and nurses working in dialysis units and related areas of medicine in the UK, and is an update of a previous version written in 2009. It aims to provide guidance on how to look after patients and how to run dialysis units, and provides standards which units should in general aim to achieve. We would not advise patients to interpret the guideline as a rulebook, but perhaps to answer the question: "what does good quality haemodialysis look like?"The guideline is split into sections: each begins with a few statements which are graded by strength (1 is a firm recommendation, 2 is more like a sensible suggestion), and the type of research available to back up the statement, ranging from A (good quality trials so we are pretty sure this is right) to D (more like the opinion of experts than known for sure). After the statements there is a short summary explaining why we think this, often including a discussion of some of the most helpful research. There is then a list of the most important medical articles so that you can read further if you want to - most of this is freely available online, at least in summary form.A few notes on the individual sections: 1. This section is about how much dialysis a patient should have. The effectiveness of dialysis varies between patients because of differences in body size and age etc., so different people need different amounts, and this section gives guidance on what defines "enough" dialysis and how to make sure each person is getting that. Quite a bit of this section is very technical, for example, the term "eKt/V" is often used: this is a calculation based on blood tests before and after dialysis, which measures the effectiveness of a single dialysis session in a particular patient. 2. This section deals with "non-standard" dialysis, which basically means anything other than 3 times per week. For example, a few people need 4 or more sessions per week to keep healthy, and some people are fine with only 2 sessions per week - this is usually people who are older, or those who have only just started dialysis. Special considerations for children and pregnant patients are also covered here. 3. This section deals with membranes (the type of "filter" used in the dialysis machine) and "HDF" (haemodiafiltration) which is a more complex kind of dialysis which some doctors think is better. Studies are still being done, but at the moment we think it's as good as but not better than regular dialysis. 4. This section deals with fluid removal during dialysis sessions: how to remove enough fluid without causing cramps and low blood pressure. Amongst other recommendations we advise close collaboration with patients over this. 5. This section deals with dialysate, which is the fluid used to "pull" toxins out of the blood (it is sometimes called the "bath"). The level of things like potassium in the dialysate is important, otherwise too much or too little may be removed. There is a section on dialysate buffer (bicarbonate) and also a section on phosphate, which occasionally needs to be added into the dialysate. 6. This section is about anticoagulation (blood thinning) which is needed to stop the circuit from clotting, but sometimes causes side effects. 7. This section is about certain safety aspects of dialysis, not seeking to replace well-established local protocols, but focussing on just a few where we thought some national-level guidance would be useful. 8. This section draws together a few aspects of dialysis which don't easily fit elsewhere, and which impact on how dialysis feels to patients, rather than the medical outcome, though of course these are linked. This is where home haemodialysis and exercise are covered. There is an appendix at the end which covers a few aspects in more detail, especially the mathematical ideas. Several aspects of dialysis are not included in this guideline since they are covered elsewhere, often because they are aspects which affect non-dialysis patients too. This includes: anaemia, calcium and bone health, high blood pressure, nutrition, infection control, vascular access, transplant planning, and when dialysis should be started.

Emergency department visits and hospitalizations among hemodialysis patients by day of the week and dialysis schedule in the United States

Background and objective

Previous reports indicated that patients on thrice-weekly hemodialysis (HD) had higher mortality rates after the 3-day interdialytic interval. However, day-of-the-week patterns of emergency department (ED) visits and hospitalizations remain under-investigated.

Methods

We conducted a retrospective cohort study of HD patients on thrice-weekly dialysis, using 2013 data from the United States Renal Data System (USRDS). We estimated crude incidence rates of ED visits and hospitalizations by day of the week and dialysis schedule (Monday, Wednesday, Friday or Tuesday, Thursday, Saturday). Using Poisson regression, we estimated case-mix adjusted rate ratios of all-cause ED visits and hospitalizations, and adjusted rates of cause-specific ED visits and hospitalizations.

Results

We identified 241,093 eligible HD patients in 2013, who had 514,773 ED visits and 301,674 hospitalizations that year. Three distinct but related patterns of outcome events were observed. Crude and adjusted incidence rates of all-cause, cardiovascular, and infection-related ED visits and hospitalizations, but not vascular-access-related events, were higher on all three HD treatment days (“dialysis-day effect”). Rates for ED visits and hospitalizations were lower on weekends than weekdays, rising appreciably from Sunday to Monday for both dialysis schedules (“post-weekend effect”); and rates were highest after the long 3-day interval between dialysis sessions for both dialysis schedules (“interdialytic-gap effect”). In contrast, rates of hospitalizations not preceded by an ED visit were nearly the same Monday through Friday and lower on weekends for both dialysis schedules.

Conclusions

Higher rates of ED visits and hospitalizations on the days of HD sessions and early in the week are a public-health concern that should stimulate research to explain these patterns and reduce the excessive morbidity and associated costs among patients on thrice-weekly HD, while improving quality of care and patient experience with dialysis.

Effect of extended hours dialysis on markers of chronic kidney disease-mineral and bone disorder in the ACTIVE Dialysis study

Background

Chronic Kidney Disease - Mineral and Bone Disorder (CKD-MBD) is a significant cause of morbidity among haemodialysis patients and is associated with pathological changes in phosphate, calcium and parathyroid hormone (PTH). In the ACTIVE Dialysis study, extended hours dialysis reduced serum phosphate but did not cause important changes in PTH or serum calcium. This secondary analysis aimed to determine if changes in associated therapies may have influenced these findings and to identify differences between patient subgroups.

Methods

The ACTIVE Dialysis study randomised 200 participants to extended hours haemodialysis (≥24 h/week) or conventional haemodialysis (≤18 h/week) for 12 months. Mean differences between treatment arms in serum phosphate, calcium and PTH; and among key subgroups (high vs. low baseline phosphate/PTH, region, time on dialysis, dialysis setting and frequency) were examined using mixed linear regression.

Results

Phosphate binder use was reduced with extended hours (− 0.83 tablets per day [95% CI -1.61, − 0.04; p = 0.04]), but no differences in type of phosphate binder, use of vitamin D, dose of cinacalcet or dialysate calcium were observed. In adjusted analysis, extended hours were associated with lower phosphate (− 0.219 mmol/L [− 0.314, − 0.124; P < 0.001]), higher calcium (0.046 mmol/L [0.007, 0.086; P = 0.021]) and no change in PTH (0.025 pmol/L [− 0.107, 0.157; P = 0.713]). The reduction in phosphate with extended hours was greater in those with higher baseline PTH and dialysing at home.

Conclusion

Extended hours haemodialysis independently reduced serum phosphate levels with minimal change in serum calcium and PTH levels. With a few exceptions, these results were consistent across patient subgroups.

Trial registration

Clinicaltrials.gov NCT00649298. Registered 1 April 2008.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1438-3) contains supplementary material, which is available to authorized users.

Independent effect of haemodialysis session frequency and duration on survival in non-indigenous Australians on haemodialysis

BACKGROUND

End-stage kidney disease patients have increased mortality compared to the general population. Haemodialysis (HD) of more frequent and of longer duration has been proposed to improve survival but it remains unclear if this is attributed to increased frequency, duration, or both. We aimed to examine the independent effects of session frequency and duration on mortality in incident HD patients.

METHODS

A retrospective cohort study was performed using data from the Australian and New Zealand Dialysis and Transplant Registry examining non-Indigenous patients aged ≥18 years who initiated HD of ≥3 sessions/week in Australia from 2001 to 2015. Initial dialysis prescription was categorized as session duration >5 h/session compared to ≤5 h/session and session frequency as >3 sessions/week compared to 3 sessions/week. Survival analysis was performed using Cox regression analysis, with multivariable analysis controlling for available covariates.

RESULTS

We examined 16 944 patients of whom 757 (4.5%) received >3 sessions/week and 518 (3.1%) received >5 h/session. After controlling for frequency, patients initiated on HD sessions >5 h had a significantly reduced risk of mortality compared with patients with HD session ≤5 h (adjusted hazard ratio (HR) = 0.57; 95% confidence interval (CI) = 0.44-0.74). In contrast, patients initiated on >3 sessions/week of HD had a similar risk of death when compared with patients on 3 sessions/week of HD (adjusted HR = 0.97; 95% CI = 0.84-1.13), after controlling for duration. Limitations include potential residual confounding and changes in exposure over time.

CONCLUSION

Longer duration rather than increased frequency of treatment appears to reduce mortality in HD patients. This has implications for management and requires further study.

A swan song for Kt/Vurea

Dialyzer clearance of urea multiplied by dialysis time and normalized for urea distribution volume (Kt/V_urea or simply Kt/V) has been used as an index of dialysis adequacy since more than 30 years. This article reviews the flaws of Kt/V, starting with a lack of proof of concept in three randomized controlled hard outcome trials (RCTs), and continuing with a long list of conditions where the concept of Kt/V was shown to be flawed. This information leaves little room for any conclusion other than that Kt/V, as an indicator of dialysis adequacy, is obsolete. The dialysis patient might benefit more if, instead, the nephrology community concentrates in the future on pursuing the optimal dialysis dose that conforms with adequate quality of life and on factors that are likely to affect outcomes more than Kt/V. These include residual renal function, volume status, dialysis length, ultrafiltration rate, the number of intra-dialytic hypotensive episodes, interdialytic blood pressure, serum potassium and phosphate, serum albumin, and C reactive protein.

The TiME Trial: A Fully Embedded, Cluster-Randomized, Pragmatic Trial of Hemodialysis Session Duration

BACKGROUND

Data from clinical trials to inform practice in maintenance hemodialysis are limited. Incorporating randomized trials into dialysis clinical care delivery should help generate practice-guiding evidence, but the feasibility of this approach has not been established.

METHODS

To develop approaches for embedding trials into routine delivery of maintenance hemodialysis, we performed a cluster-randomized, pragmatic trial demonstration project, the Time to Reduce Mortality in ESRD (TiME) trial, evaluating effects of session duration on mortality (primary outcome) and hospitalization rate. Dialysis facilities randomized to the intervention adopted a default session duration ≥4.25 hours (255 minutes) for incident patients; those randomized to usual care had no trial-driven approach to session duration. Implementation was highly centralized, with no on-site research personnel and complete reliance on clinically acquired data. We used multiple strategies to engage facility personnel and participating patients.

RESULTS

The trial enrolled 7035 incident patients from 266 dialysis units. We discontinued the trial at a median follow-up of 1.1 years because of an inadequate between-group difference in session duration. For the primary analysis population (participants with estimated body water ≤42.5 L), mean session duration was 216 minutes for the intervention group and 207 minutes for the usual care group. We found no reduction in mortality or hospitalization rate for the intervention versus usual care.

CONCLUSIONS

Although a highly pragmatic design allowed efficient enrollment, data acquisition, and monitoring, intervention uptake was insufficient to determine whether longer hemodialysis sessions improve outcomes. More effective strategies for engaging clinical personnel and patients are likely required to evaluate clinical trial interventions that are fully embedded in care delivery.

No Survival Benefit in Octogenarians and Nonagenarians with Extended Hemodialysis Treatment Time

BACKGROUND

The population of elderly end-stage renal disease patients initiating dialysis is rapidly growing. Although longer treatment is supposed to benefit for hemodialysis (HD) patients through more solute clearance and slower fluid removal, it is not yet clear how treatment session length affects mortality risk in octogenarians and nonagenarians.

METHODS

In a cohort of 112,026 incident HD patients between 2007 and 2011, we examined the association of treatment session length with all-cause mortality, adjusting for demographics and comorbid conditions. We also used restricted spline functions for age to evaluate continuous changes in the association of short (< 210 min) and extended (≥240 min) HD treatment (vs. 210 to < 240 min) with all-cause mortality over continuous age.

RESULTS

During the first 91 days of dialysis, patients aged ≥80 years tended to have the lowest treatment session length (median [interquartile range] 211 [193-230] min, r > 0.5). Longer treatment was associated with better survival in patients < 65 and 65 to < 80 years but not in octogenarians/nonagenarians. The association of extended treatment (≥240 min) with better survival was attenuated across age and not significant among patients aged ≥80 years with a hazard ratio of 1.10 (95% CI 0.99-1.20). Shorter treatment sessions (< 210 min) was associated with higher mortality across all age groups.

CONCLUSION

Extended HD was not associated with lower mortality among octogenarians and nonagenarians, while it was associated with better survival among younger patients. Further studies are needed to determine the optimal treatment session length in elderly incident HD patients.