Hemodiafiltration for children with stage 5 chronic kidney disease: technical aspects and outcomes.

Despite significant medical and technical improvements in the field of dialysis, the morbidity and mortality among patients with chronic kidney disease (CKD) stage 5 on dialysis remains extremely high. Hemodiafiltration (HDF), a dialysis method that combines the two main principles of hemodialysis (HD) and hemofiltration-diffusion and convection-has had a positive impact on survival when delivered with a high convective dose. Improved outcomes with HDF have been attributed to the following factors: HDF removes middle molecular weight uremic toxins including inflammatory cytokines, increases hemodynamic stability, and reduces inflammation and oxidative stress compared to conventional HD. Two randomized trials in adults have shown improved survival with HDF compared to high-flux HD. A large prospective cohort study in children has shown that HDF attenuated the progression of cardiovascular disease, improved bone turnover and growth, reduced inflammation, and improved blood pressure control compared to conventional HD. Importantly, children on HDF reported fewer headaches, dizziness, and cramps; had increased physical activity; and improved school attendance compared to those on HD. In this educational review, we discuss the technical aspects of HDF and results from pediatric studies, comparing outcomes on HDF vs. conventional HD. Convective volume, the cornerstone of treatment with HDF and a key determinant of outcomes in adult randomized trials, is discussed in detail, including the practical aspects of achieving an optimal convective volume.

Associations of Iron Sucrose and Intradialytic Blood Pressure.

RATIONALE & OBJECTIVE: Intradialytic hypotension and intradialytic hypertension are associated with morbidity and mortality in hemodialysis (HD). Many factors can contribute to intra-HD blood pressure (BP) changes, such as drugs with vasoactive properties that can destabilize an already tenuous BP. Intravenous iron sucrose is commonly administered to correct iron deficiency; however, its reported associations with altered hemodynamics have not been consistent. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 950 outpatients receiving maintenance HD. EXPOSURE: Iron sucrose administered during HD. OUTCOME: Intradialytic hypotension, intradialytic hypertension, systolic blood pressure parameters. ANALYTICAL APPROACH: Unadjusted and adjusted Poisson and linear repeated measures regression models. RESULTS: The mean age of patients included in the study was 53±22 years, 43% were female, and 38% were Black. Mean pre-HD SBP was 152±26 (SD) mm Hg. At baseline, the patients who received higher doses of iron sucrose tended to have diabetes, have longer HD sessions, and have a higher frequency of erythropoiesis-stimulating agent use, compared with those who did not receive iron sucrose. In adjusted models, higher doses of iron sucrose were associated with an 11% lower rate of intradialytic hypotension (incidence rate ratio [IRR] for iron sucrose≥100mg vs 0 mg, 0.89 [95% CI, 0.85-0.94]). In adjusted analyses, the administration of higher doses of iron sucrose during HD was associated with intradialytic hypertension (IRR for iron sucrose≥100mg vs 0 mg, 1.07 [95% CI, 1.04-1.10]). LIMITATIONS: Nonavailability of the precise iron sucrose formulation (volume), laboratory data for each HD session, and outpatient medications. Objective measures of volume status, home medications, and symptom data were not recorded in this study. CONCLUSIONS: We observed an independent association of intravenous iron sucrose administration during HD with a lower risk of intradialytic hypotension and higher risk of intradialytic hypertension. Future studies to better understand the mechanisms underlying these associations are warranted. PLAIN-LANGUAGE SUMMARY: Intradialytic hypotension and intradialytic hypertension are common among patients on hemodialysis, and they are associated with morbidity and mortality. Although many factors may contribute to these risks, medications administered during hemodialysis play an important role. We studied the significance of the intravenous iron sucrose used to treat iron deficiency and the impact it may have on blood pressure during dialysis. In our study of 950 outpatient hemodialysis patients, we observed that administration of iron sucrose was associated with higher systolic blood pressure (during and after hemodialysis sessions) as well as a lower risk of intradialytic hypotension. We also observed that higher doses of iron sucrose are associated with the development of intradialytic hypertension.

Technical requirements and devices available for long-term hemodialysis in children-mind the gap!

Children requiring long-term kidney replacement therapy are a "rare disease" cohort. While the basic technical requirements for hemodialysis (HD) are similar in children and adults, key aspects of the child's cardiovascular anatomy and hemodynamic specifications must be considered. In this article, we describe the technical requirements for long-term HD therapy for children and the devices that are currently available around the world. We highlight the characteristics and major technical shortcomings of permanent central venous catheters, dialyzers, dialysis machines, and software available to clinicians who care for children. We show that currently available HD machines are not equipped with appropriately small circuits and sensitive control mechanisms to perform safe and effective HD in the youngest patients. Manufacturers limit their liability, and health regulatory agencies permit the use of devices, only in children according to the manufacturers' pre-specified weight limitations. Although registries show that 6-23% of children starting long-term HD weigh less than 15 kg, currently, there is only one long-term HD device that is cleared for use in children weighing 10 to 15 kg and none is available and labelled for use in children weighing less than 10 kg anywhere in the world. Thus, many children are being treated "off-label" and are subject to interventions delivered by medical devices that lack pediatric safety and efficacy data. Moreover, recent improvements in dialysis technology offered to adult patients are denied to most children. We, in turn, advocate for concerted action by pediatric nephrologists, industry, and health regulatory agencies to increase the development of dedicated HD machines and equipment for children.

Monitoring of minerals level in dialysate during hemodialysis treatment of kidney patients using LIBS technique.

Chronic kidney patients may have difficulties in blood filtration to eliminate the waste from the blood and to maintain the level of the minerals in the blood. Hemodialysis (HD) is an artificial way to remove the waste from the blood of a kidney patient and to maintain the proper mineral level in the blood. Reverse osmosis (RO) water having less total dissolved solids (TDS) < 50 ppm is used to prepare dialysis fluid/dialysate in dialysis with two chemicals (electrolytes and salts such as sodium bicarbonate). To check the purity of RO water from various RO machines used to prepare dialysate, which is vital for the safety of the patient, the laser-induced breakdown spectroscopy (LIBS) technique has been used. Also, the amount of replacement of electrolytes/minerals between the blood of the patient and dialysate after dialysis has been checked/determined for two different machines: hemodialysis machine (HDM) and on-line hemo-dia filtration machine (on-line HDF machine). It is observed that the proper amount of electrolytes (Na, Ca, and Mg) are maintained/normalized (depending upon patient's need), excess K is removed, and excess urea and creatinine is removed continuously from the blood of a patient during dialysis treatment which is essential for the better health of a kidney patient. Our results show that the RO water used in on-line HDF machine is purer (i.e., ultrapure); therefore, the quality of life of a kidney patient may be better if dialysis is performed with the on-line HDF machine. The experimental results also show that the filtration capacity of the dialyzer decreases after reusing it many times for dialysis treatment.

Staphylococcus aureus Bacteremia Among Patients Receiving Maintenance Hemodialysis: Trends in Clinical Characteristics and Outcomes.

RATIONALE & OBJECTIVE: Staphylococcus aureus (Saureus) bacteremia (SAB) is associated with morbidity and mortality in patients receiving maintenance hemodialysis (HD). We evaluated changes in clinical and bacterial characteristics, and their associations with clinical outcomes with SAB in this population over a 21-year period. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 453 hospitalized, non-neutropenic adults receiving maintenance HD who developed monomicrobial SAB between 1995 and 2015. EXPOSURE: Clinical characteristics and bacterial genotype. OUTCOME: All-cause and SAB-attributable mortality, persistent bacteremia, and metastatic complications. ANALYTICAL APPROACH: Proportions of participants experiencing each outcome were calculated overall and by calendar year. Secular trends were estimated using binomial risk regression, a generalized linear model with the log link function for a binomial outcome. Associations with outcomes were estimated using logistic regression. RESULTS: Over the 21-year study period, patients receiving maintenance HD experienced significant increases in age- and diabetes-adjusted SAB-attributable mortality (0.45% [95% CI, 0.36%-0.46%] per year), persistent bacteremia (0.86% [95% CI, 0.14%-1.55%] per year), metastatic complications (0.84% [95% CI, 0.11%-1.56%] per year), and infection with the virulent Saureus clone USA300 (1.47% [95% CI, 0.33%-2.52%] per year). Over time, the suspected source of SAB was less likely to be a central venous catheter (-1.32% [95% CI, -2.05 to-0.56%] per year) or arteriovenous graft (-1.08% [95% CI, -1.54 to-0.56] per year), and more likely to be a nonvascular access source (1.89% [95% CI, 1.29%-2.43%] per year). Patients with a nonvascular access suspected source of infection were more likely to die as a result of their S aureus infection (OR, 3.20 [95% CI, 1.36-7.55]). The increase in USA300 infections may have contributed to the observed increase in persistent bacteremia (OR, 2.96 [95% CI, 1.12-7.83]) but did not explain the observed increases in SAB-attributable mortality (OR, 0.83 [95% CI, 0.19-3.61]) or metastatic complications (OR, 1.34 [95% CI, 0.53-3.41]). LIMITATIONS: Single-center, inpatient cohort. CONCLUSIONS: The clinical and molecular epidemiology of SAB in patients receiving maintenance HD has changed over time, with an increase in SAB-attributable mortality and morbidity despite a decline in catheter-related infections.

Cancer Mortality in People Receiving Dialysis for Kidney Failure: An Australian and New Zealand Cohort Study, 1980-2013.

RATIONALE & OBJECTIVE: Cancer is a significant cause of morbidity in the population with kidney failure; however, cancer mortality in people undergoing dialysis has not been well described. We sought to compare cancer mortality in people on dialysis for kidney failure with cancer mortality in the general population. STUDY DESIGN: A retrospective cohort study using linked health-administrative and dialysis registry data. SETTING & PARTICIPANTS: All people receiving dialysis represented in the Australian and New Zealand Dialysis and Transplantation Registry, 1980-2013. EXPOSURE: Dialysis; hemodialysis (HD) and peritoneal dialysis (PD). OUTCOME: Death and underlying cause of death ascertained using health administrative data and classified using International Classification of Diseases, Tenth Revision, Australian Modification (ICD-10-AM) codes. ANALYTICAL APPROACH: Indirect standardization on age at death, sex, year, and country to estimate standardized mortality ratios (SMR). RESULTS: Over 269,598 person years of observation, 34,100 deaths occurred among 59,648 people on dialysis, including 3,677 cancer deaths. The relative risk of all-site cancer death in dialysis was twice (SMR, 2.4 [95% CI, 2.33-2.49]) that of the general population and highest for oral and pharynx cancers (SMR, 24.3 [95% CI, 18.0-31.5]) and multiple myeloma (SMR, 22.5 [95% CI, 20.3-23.9]). Women on dialysis had a significantly higher risk of all-site cancer mortality (SMR, 2.7 [95% CI, 2.59-2.89]) compared with men (SMR, 2.3 [95% CI, 2.17-2.36]) (P < 0.001). People on HD (SMR, 2.2 [95% CI, 2.11-2.30]) experienced greater excess deaths from all-site cancer compared with people on PD (SMR, 1.3 [95% CI, 1.23-1.44]). Excess deaths have gradually decreased over time for all-site, multiple myeloma, and kidney cancers (P < 0.001) but have not kept up with improvements in the general population. By contrast, among people receiving dialysis, excess deaths increased for colorectal and lung cancers (P < 0.001). LIMITATIONS: Confirmation of cancer diagnoses and population incidence data were not available; inability to exclude pre-existing cancers. CONCLUSIONS: People on dialysis experience excess all-site and site-specific cancer mortality compared with the general population. Mortality differs by modality type, age, and sex. Understanding the role of kidney failure and other morbidities in the treatment of cancer is important for shared decision-making regarding cancer treatments and identifying potential approaches to improve outcomes.

A Novel Approach for Managing Protein-Energy Wasting in People With Kidney Failure Undergoing Maintenance Hemodialysis: Rationale and Call for Trials.

Protein-energy wasting (PEW) is a unique presentation of protein-energy malnutrition in people with kidney disease that is characterized by body protein catabolism exceeding anabolism. PEW is especially common in patients undergoing maintenance hemodialysis (HD) treatment. Dietary guidelines for managing PEW in HD patients primarily focus on protein adequacy and typically promote the intake of animal-based protein foods. Although intake of protein and essential amino acids is important for protein synthesis, the emphasis on protein adequacy largely fails to address-and may actually exacerbate-many of the root causes of PEW. This perspective examines the dietary determinants of PEW in people undergoing HD treatment, with an emphasis on upstream disease-related factors that reduce dietary protein utilization and impair dietary intakes. From this, we present a theoretical diet model for managing PEW that includes etiology-based dietary strategies to address barriers to intake and treat disease-related factors, as well as supportive dietary strategies to promote adequate energy and protein intakes. Given the complexity of diet-disease interactions in the pathogenesis of PEW, and its ongoing burden in HD patients, interventional trials are urgently needed to evaluate alternative diet therapy approaches for PEW in this population.

Arteriovenous Access Type and Risk of Mortality, Hospitalization, and Sepsis Among Elderly Hemodialysis Patients: A Target Trial Emulation Approach.

RATIONALE & OBJECTIVE: Evidence is mixed regarding the optimal choice of the first permanent vascular access for elderly patients receiving hemodialysis (HD). Lacking data from randomized controlled trials, we used a target trial emulation approach to compare arteriovenous fistula (AVF) versus arteriovenous graft (AVG) creation among elderly patients receiving HD. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Elderly patients included in the US Renal Data System who initiated HD with a catheter and had an AVF or AVG created within 6 months of starting HD. EXPOSURE: Creation of an AVF versus an AVG as the incident arteriovenous access. OUTCOMES: All-cause mortality, all-cause and cause-specific hospitalization, and sepsis. ANALYTICAL APPROACH: Target trial emulation approach, high-dimensional propensity score and inverse probability of treatment weighting, and instrumental variable analysis using the proclivity of the operating physician to create a fistula as the instrumental variable. RESULTS: A total of 19,867 patients were included, with 80.1% receiving an AVF and 19.9% an AVG. In unweighted analysis, AVF creation was associated with significantly lower risks of mortality and hospitalization, especially within 6 months after vascular access creation. In inverse probability of treatment weighting analysis, AVF creation was associated with lower incidences of mortality and hospitalization within 6 months after creation (hazard ratios of 0.82 [95% CI, 0.75-0.91] and 0.82 [95% CI, 0.78-0.87] for mortality and all-cause hospitalization, respectively), but not between 6 months and 3 years after access creation. No association between AVF creation and mortality, sepsis, or all-cause, cardiovascular disease-related, or infection-related hospitalization was found in instrumental variable analyses. However, AVF creation was associated with a lower risk of access-related hospitalization not due to infection. LIMITATIONS: Potential for unmeasured confounding, analyses limited to elderly patients, and absence of data on actual access use during follow-up. CONCLUSIONS: Using observational data to emulate a target randomized controlled trial, the type of initial arteriovenous access created was not associated with the risks of mortality, sepsis, or all-cause, cardiovascular disease-related, or infection-related hospitalization among elderly patients who initiated HD with a catheter.

Association of Frailty With Thrombosis of Hemodialysis Vascular Access: A Prospective Taiwanese Cohort Study.

RATIONALE & OBJECTIVE: Frailty, a multidimensional construct, has been associated with poor outcomes in patients receiving maintenance dialysis. This study assessed the association of frailty with dialysis vascular access patency. STUDY DESIGN: Multicenter prospective cohort study. SETTING & PARTICIPANTS: 761 prevalent patients receiving hemodialysis at 9 centers in Taiwan as of January 2018. EXPOSURE: Performance-based frailty was defined as 3 of the following: unintentional weight loss, weakness, exhaustion, low physical activity, and slow gait speed. Patients were categorized as prefrail if they had 1 or 2 of these characteristics. OUTCOME: Rate of and time to dialysis access thrombosis. Data regarding vascular access events were collected for 30 months after enrollment through December 31, 2020. ANALYTICAL APPROACH: Logistic regression analysis was used to estimate the association of clinical characteristics with frailty. Cox proportional hazards regression analysis was used to estimate the association of frailty with vascular access thrombosis adjusted for known clinical risk factors. RESULTS: The patients' mean age was 66 years, 46% were female, 18% had synthetic graft accesses, and 82% arteriovenous fistulas. Overall, 31% were frail, 35% were prefrail, and 34% were not frail. The frailty phenotype was associated with age, female sex, low body mass index, diabetes mellitus, and prior stroke. During a median follow-up of 731 days, 161 patients (21%) had access thrombosis events (not frail, 14%; prefrail, 20%; frail, 30%; P < 0.001). Frail patients had a higher risk of vascular access thrombosis than nonfrail patients (HR, 2.31 [95% CI, 1.55-3.39], P < 0.001). After multivariable adjustment for age and comorbidities, frailty remained significantly associated with access thrombosis for both fistulas and grafts. LIMITATIONS: Limited generalizability and potential residual confounding. CONCLUSIONS: Frailty is associated with an increased risk of vascular access thrombosis. These findings highlight the risks of access failure experienced by frail patients receiving hemodialysis.

Twice-Weekly Hemodialysis With Adjuvant Pharmacotherapy and Transition to Thrice-Weekly Hemodialysis: A Pilot Study.

RATIONALE & OBJECTIVE: Thrice-weekly hemodialysis (HD) is the most common treatment modality for kidney failure in the United States. We conducted a pilot study to assess the feasibility and safety of incremental-start HD in patients beginning maintenance HD. STUDY DESIGN: Pilot study. SETTING & PARTICIPANTS: Adults with estimated glomerular filtration rate (eGFR) ≥5 mL/min/1.73 m2 and urine volume ≥500 mL/d beginning maintenance HD at 14 outpatient dialysis units. EXPOSURE: Randomized allocation (1:1 ratio) to twice-weekly HD and adjuvant pharmacologic therapy for 6 weeks followed by thrice-weekly HD (incremental HD group) or thrice-weekly HD (conventional HD group). OUTCOME: The primary outcome was feasibility. Secondary outcomes included changes in urine volume and solute clearance. RESULTS: Of 77 patients invited to participate, 51 consented to do so, representing 66% of eligible patients. We randomized 23 patients to the incremental HD group and 25 patients to the conventional HD group. Protocol-based loop diuretics, sodium bicarbonate, and patiromer were prescribed to 100%, 39%, and 17% of patients on twice-weekly HD, respectively. At a mean follow-up of 281.9 days, participant adherence was 96% to the HD schedule (22 of 23 and 24 of 25 in the incremental and conventional groups, respectively) and 100% in both groups to serial timed urine collection. The incidence rate ratio for all-cause hospitalization was 0.31 (95% CI, 0.08-1.17); and 7 deaths were recorded (1 in the incremental and 6 in the conventional group). At week 24, the incremental HD group had lower declines in urine volume (a difference of 51.0 [95% CI, -0.7 to 102.8] percentage points) and in the averaged urea and creatinine clearances (a difference of 57.9 [95% CI, -22.6 to 138.4] percentage points). LIMITATIONS: Small sample size, time-limited twice-weekly HD. CONCLUSIONS: It is feasible to enroll patients beginning maintenance HD into a randomized study of incremental-start HD with adjuvant pharmacotherapy who adhere to the study protocol during follow-up. Larger multicenter clinical trials are indicated to determine the efficacy and safety of incremental HD with longer twice-weekly HD periods. FUNDING: Funding was provided by Vifor Inc. TRIAL REGISTRATION: Registered at ClinicalTrials.gov, identifier NCT03740048.

Epidemiology and Risk Factors for Hemodialysis Access-Associated Infections in Children: A Prospective Cohort Study From the SCOPE Collaborative.

RATIONALE & OBJECTIVE: Infections cause significant morbidity and mortality for children receiving maintenance hemodialysis (HD). The Standardizing Care to Improve Outcomes in Pediatric End-Stage Kidney Disease (SCOPE) Collaborative is a quality-improvement initiative aimed at reducing dialysis-associated infections by implementing standardized care practices. This study describes patient-level risk factors for catheter-associated bloodstream infections (CA-BSIs) and examines the association between dialysis center-level compliance with standardized practices and risk of CA-BSI. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: Children enrolled in SCOPE between June 2013 and July 2019. EXPOSURES: Data were collected on patient characteristics and center-level compliance with HD catheter care practices across the study period. Centers were categorized as consistent, dynamic (improved compliance over the study period), or inconsistent performers based on frequency of compliance audit submission and changes in compliance with HD care practices over time. OUTCOME: CA-BSIs. ANALYTICAL APPROACH: Generalized linear mixed models were used to evaluate (1) patient-level risk factors for CA-BSI and (2) associations between change in center-level compliance and CA-BSIs. RESULTS: The cohort included 1,277 children from 35 pediatric dialysis centers; 1,018 (79.7%) had a catheter and 259 (20.3%) had an arteriovenous fistula or graft. Among children with a catheter, mupirocin use at the catheter exit site was associated with an increased rate of CA-BSIs (rate ratio [RR], 4.45; P = 0.004); the use of no antibiotic agent at the catheter exit site was a risk factor of borderline statistical significance (RR, 1.79; P = 0.05). Overall median compliance with HD catheter care practices was 87.5% (IQR, 77.3%-94.0%). Dynamic performing centers showed a significant decrease in CA-BSI rates over time (from 2.71 to 0.71 per 100 patient-months; RR, 0.98; P < 0.001), whereas no significant change in CA-BSI rates was detected among consistent or inconsistent performers. LIMITATIONS: Lack of data on adherence to HD care practices on the individual patient level. CONCLUSIONS: Improvement in compliance with standardized HD care practices over time may lead to a reduction in dialysis-associated infections.

Integrating Patient Activation Into Dialysis Care.

Patient activation, the measure of patients' readiness and willingness to manage their own health care, is low among people receiving in-center hemodialysis, which is exacerbated because such centers are commonly set up for patients to passively receive care. In our pursuit of person-centered care and value-based medicine, enabling patients to take a more active role in their care can lead to healthy behaviors, with subsequent reductions in individual burden and costs to the health care system. To improve patient activation, we need to embrace a patient-first approach and combine it with ways to equip patients to thrive with self-management. This requires changes in the training of the health care team as well as changes in care delivery models, promoting interventions such as health coaching and peer mentoring, while leveraging technology to enable self-access to records, self-monitoring, and communication with providers. We also need health care policies that encourage a focus on patient-identified goals, including more attention to patient-reported outcomes. In this article, we review the current status of patient activation in dialysis patients, outline some of the available interventions, and propose steps to change the dynamics of the current system to move toward a more active role for patients in their care.

Lung Ultrasound to Diagnose Pulmonary Congestion Among Patients on Hemodialysis: Comparison of Full Versus Abbreviated Scanning Protocols.

RATIONALE & OBJECTIVE: Pulmonary congestion contributes to morbidity and mortality in patients with kidney failure on hemodialysis, but physical assessment is an insensitive approach to its detection. Lung ultrasound is useful for assessing the presence and severity of pulmonary congestion, but the most widely validated 28-zone study is cumbersome. We sought to compare abbreviated 4-, 6-, and 8-zone studies to 28-zone studies. STUDY DESIGN: Diagnostic test study. SETTING & PARTICIPANTS: Convenience sample of 98 patients with kidney failure on hemodialysis presenting to an emergency department in the United States. TESTS COMPARED: 4-, 6-, and 8-zone lung ultrasound studies versus a 28-zone lung ultrasound. OUTCOME: Prediction of pulmonary congestion and 30-day mortality. RESULTS: All patients completed a 28-zone lung ultrasound. Correlation coefficients (nonparametric Spearman) between each of the studies were high (all values > 0.84). Bland-Altman analysis showed good agreement. Each of the short-form studies discriminated well with area under the receiver-operator characteristic curve > 0.83 for no-to-mild versus moderate-to-severe pulmonary congestion. During a median follow-up period of 778 days, 46 (47%) died. Patients with moderate-to-severe pulmonary congestion on lung ultrasound had a 30-day mortality rate similar to that observed among patients with no-to-mild pulmonary congestion (OR, 0.95 [95% CI, 0.70-1.29]). LIMITATIONS: Single-center study conducted in an emergency care setting, convenience sample of patients, and lack of long-term follow-up data. CONCLUSIONS: Among hemodialysis patients presenting to an emergency department, 4-, 6-, or 8-zone lung ultrasounds were comparable to 28-zone studies for the assessment of pulmonary congestion. The mortality rates did not differ between those with no-to-mild and moderate-to-severe pulmonary congestion.

10-Year clinical outcomes of hemodialysis patients with peripheral arterial disease due to infrainguinal disease undergoing endovascular therapy.

Although symptomatic peripheral arterial disease (PAD) is common in patients with hemodialysis (HD), few studies have evaluated the long-term clinical outcomes of revascularization in this population. The aim of the current study was to investigate the 10-year clinical outcomes of HD patients with PAD undergoing endovascular therapy (EVT). We retrospectively analyzed 750 limbs from 578 HD patients with symptomatic PAD due to infrainguinal lesions, treated with EVT, between May 2004 and November 2011. The primary outcome was 10-year mortality and the secondary outcome was 10-year freedom from major adverse limb events (MALEs). Predictors for each outcome were evaluated by Cox proportional-hazards model. The 10-year rate of survival and freedom from MALEs was 23.6 ± 3.1% and 76.4 ± 2.9%, respectively. In the multivariate analysis, patients with over 80 years [hazard ratio (HR) 2.10; 95% confidence interval (CI) 1.58-2.80; p < 0.001], non-ambulatory status (HR 1.55; 95% CI 1.19-2.03; p = 0.001), absence of hypertension (HR 1.59; 95% CI 1.19-2.08; p = 0.001), heart failure (HR 1.36; 95% CI 1.02-1.80; p = 0.03), and tissue loss (HR 1.65; 95% CI 1.28-2.12; p < 0.001) were at an increased risk of 10-year mortality. Cerebrovascular diseases (HR 1.60; 95% CI 1.03-2.49; p = 0.038), no cilostazol use (HR 1.69; 95% CI 1.09-2.70; p = 0.021), tissue loss (HR 3.87; 95% CI 2.37-6.34; p < 0.001), and poor below-the-knee (BTK) run-off (HR 1.68; 95% CI 1.04-2.71; p = 0.035) were significantly associated with MALEs. After risk stratification analysis based on risk score assignment according to number of predictors, 10-year survival and freedom from MALE were lower in the higher score groups (10-year survival rates according to number of risk factors: 0, 35.1%; 1, 20.3%; 2-5, 10.8%; respectively, p < 0.001, 10-year freedom from MALE rates in patients with greater number of risk factors: 0-1, 90.2%; 2-3, 65.5%; 4-5, 61.6%; respectively, p < 0.001). The 10-year clinical outcomes after EVT for HD patients with PAD due to infrainguinal disease were clinically suboptimal. Risk stratification based on these predictors before EVT would be useful in estimating future adverse outcome.

Home Versus Facility Dialysis and Mortality in Australia and New Zealand.

RATIONALE & OBJECTIVE: Mortality is an important outcome for all dialysis stakeholders. We examined associations between dialysis modality and mortality in the modern era. STUDY DESIGN: Observational study comparing dialysis inception cohorts 1998-2002, 2003-2007, 2008-2012, and 2013-2017. SETTING & PARTICIPANTS: Australia and New Zealand (ANZ) dialysis population. EXPOSURE: The primary exposure was dialysis modality: facility hemodialysis (HD), continuous ambulatory peritoneal dialysis (CAPD), automated PD (APD), or home HD. OUTCOME: The main outcome was death. ANALYTICAL METHODS: Cause-specific proportional hazards models with shared frailty and subdistribution proportional hazards (Fine and Gray) models, adjusting for available confounding covariates. RESULTS: In 52,097 patients, the overall death rate improved from ~15 deaths per 100 patient-years in 1998-2002 to ~11 in 2013-2017, with the largest cause-specific contribution from decreased infectious death. Relative to facility HD, mortality with CAPD and APD has improved over the years, with adjusted hazard ratios in 2013-2017 of 0.88 (95% CI, 0.78-0.99) and 0.91 (95% CI, 0.82-1.00), respectively. Increasingly, patients with lower clinical risk have been adopting APD, and to a lesser extent CAPD. Relative to facility HD, mortality with home HD was lower throughout the entire period of observation, despite increasing adoption by older patients and those with more comorbidities. All effects were generally insensitive to the modeling approach (initial vs time-varying modality, cause-specific versus subdistribution regression), different follow-up time intervals (5 year vs 7 year vs 10 year). There was no effect modification by diabetes, comorbidity, or sex. LIMITATIONS: Potential for residual confounding, limited generalizability. CONCLUSIONS: The survival of patients on PD in 2013-2017 appears greater than the survival for patients on facility HD in ANZ. Additional research is needed to assess whether changing clinical risk profiles over time, varied dialysis prescription, and morbidity from dialysis access contribute to these findings.

Efficacy and Safety of Paclitaxel-Coated Balloon Angioplasty for Dysfunctional Arteriovenous Fistulas: A Multicenter Randomized Controlled Trial.

RATIONALE & OBJECTIVE: Previous studies have illustrated the potential superiority of drug-coated balloons (DCBs) in maintaining patency after initial angioplasty for arteriovenous fistula (AVF) dysfunction due to stenosis. Our trial evaluated the efficacy and safety of DCBs for preventing fistula restenosis in Chinese hemodialysis patients. STUDY DESIGN: Multicenter, prospective, randomized, open-label, blinded end point, controlled trial. SETTINGS & PARTICIPANTS: A total of 161 hemodialysis patients with fistula dysfunction from 10 centers in China. INTERVENTION: Participants were randomized 1:1 to treatment with initial dilation followed by DCB angioplasty or conventional high-pressure balloon (HPB) angioplasty. OUTCOMES: The primary end point was target lesion primary patency defined as the target lesion intervention-free survival in conjunction with an ultrasonography-measured peak systolic velocity ratio (PSVR) ≤2.0 at 6 months. The secondary end points included 1) device, technical, clinical, and procedural success; 2) major adverse events; 3) degree of target lesion stenosis at 6 months; and 4) clinically driven target lesion and target shunt revascularization within 12 months. RESULTS: The percentage with target lesion primary patency as defined by a PSVR ≤2.0 was higher in the DCB group than in the control group (65% vs 37%, respectively; rate difference, 28% [95% CI, 13%-43%]; P <0.001) at 6 months. The target lesion and target shunt intervention-free survival of the DCB group were not superior to those of the control group at 6 months (P = 0.3 and P = 0.2, respectively) but were superior at 12 months (target lesion intervention-free survival: 73% for DCB vs 58% for control [P = 0.04]; target shunt intervention-free survival: 73% for DCB vs 57% for control [P = 0.04]). The average degree of target lesion stenoses at 6 months was not significantly different between the 2 groups (44% ± 16% for DCB vs 49% ± 18% for control; P = 0.09). There were no significant differences in major adverse events or in device, technical, clinical, or procedural success rates between the groups. LIMITATIONS: Small sample size; short follow-up period; procedural differences between the 2 groups such as unequal inflation times and balloon lengths. CONCLUSIONS: Compared to conventional HPB angioplasty, DCB treatment achieved superior primary patency defined using PSVR measured at 6 months and superior intervention-free survival of both the target lesion and the target shunt at 12 months without evidence of greater adverse events. FUNDING: Funded by ZhuHai Cardionovum Medical Device Co., Ltd. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT02962141.

Hemodialysis Emergencies: Core Curriculum 2021.

Since maintenance hemodialysis (HD) first became available in the United States in 1962, there has been tremendous growth in the population of patients with kidney failure. HD has become a routine treatment carried out in outpatient clinics, hospitals, nursing facilities, and in patients' homes. Although it is a complex procedure, HD is quite safe. Serious complications are uncommon due to the use of modern HD machines and water treatment systems as well as the development of strict protocols to monitor various aspects of the HD treatment. The practicing nephrologist must be knowledgeable about life-threatening complications that can occur during HD and be able to recognize, manage, and prevent them. This installment in the AJKD Core Curriculum in Nephrology reviews the pathogenesis, management, and prevention of 9 HD emergencies. The HD emergencies covered include dialyzer reactions, dialysis disequilibrium syndrome, uremic/dialysis-associated pericarditis, air embolism, venous needle dislodgement, vascular access hemorrhage, hemolysis, dialysis water contamination, and arrhythmia episodes.

Arteriovenous Vascular Access-Related Procedural Burden Among Incident Hemodialysis Patients in the United States.

RATIONALE & OBJECTIVE: As the proportion of arteriovenous fistulas (AVFs) compared with arteriovenous grafts (AVGs) in the United States has increased, there has been a concurrent increase in interventions. We explored AVF and AVG maturation and maintenance procedural burden in the first year of hemodialysis. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: Patients initiating hemodialysis from July 1, 2012, to December 31, 2014, and having a first-time AVF or AVG placement between dialysis initiation and 1 year (N = 73,027), identified using the US Renal Data System (USRDS). PREDICTORS: Patient characteristics. OUTCOME: Successful AVF/AVG use and intervention procedure burden. ANALYTICAL APPROACH: For each group, we analyzed interventional procedure rates during maturation maintenance phases using Poisson regression. We used proportional rate modeling for covariate-adjusted analysis of interventional procedure rates during the maintenance phase. RESULTS: During the maturation phase, 13,989 of 57,275 patients (24.4%) in the AVF group required intervention, with therapeutic interventional requirements of 0.36 per person. In the AVG group 2,904 of 15,572 patients (18.4%) required intervention during maturation, with therapeutic interventional requirements of 0.28 per person. During the maintenance phase, in the AVF group 12,732 of 32,115 patients (39.6%) required intervention, with a therapeutic intervention rate of 0.93 per person-year. During maintenance phase, in the AVG group 5,928 of 10,271 patients (57.7%) required intervention, with a therapeutic intervention rate of 1.87 per person-year. For both phases, the intervention rates for AVF tended to be higher on the East Coast while those for AVG were more uniform geographically. LIMITATIONS: This study relies on administrative data, with monthly recording of access use. CONCLUSIONS: During maturation, interventions for both AVFs and AVGs were relatively common. Once successfully matured, AVFs had lower maintenance interventional requirements. During the maturation and maintenance phases, there were geographic variations in AVF intervention rates that warrant additional study.

International Comparisons of Native Arteriovenous Fistula Patency and Time to Becoming Catheter-Free: Findings From the Dialysis Outcomes and Practice Patterns Study (DOPPS).

RATIONALE & OBJECTIVE: Optimizing vascular access use is crucial for long-term hemodialysis patient care. Because vascular access use varies internationally, we examined international differences in arteriovenous fistula (AVF) patency and time to becoming catheter-free for patients receiving a new AVF. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 2,191 AVFs newly created in 2,040 hemodialysis patients in 2009 to 2015 at 466 randomly selected facilities in the Dialysis Outcomes and Practice Patterns Study (DOPPS) from the United States, Japan, and EUR/ANZ (Belgium, France, Germany, Italy, Spain, Sweden, United Kingdom, Australia, and New Zealand). PREDICTORS: Demographics, comorbid conditions, dialysis vintage, body mass index, AVF location, and country/region. OUTCOMES: Primary/cumulative AVF patency (from creation), primary/cumulative functional patency (from first use), catheter dependence duration, and mortality. ANALYTICAL APPROACH: Outcomes estimated using Cox regression. RESULTS: Across regions, mean patient age ranged from 61 to 66 years, with male preponderance ranging from 55% to 66%, median dialysis vintage of 0.3 to 3.2 years, with 84%, 54%, and 32% of AVFs created in the forearm in Japan, EUR/ANZ, and United States, respectively. Japan displayed superior primary and cumulative patencies due to higher successful AVF use, whereas cumulative functional patency was similar across regions. AVF patency associations with age and other patient characteristics were weak or varied considerably between regions. Catheter-dependence following AVF creation was much longer in EUR/ANZ and US patients, with nearly 70% remaining catheter dependent 8 months after AVF creation when AVFs were not successfully used. Not using an arteriovenous access within 6 months of AVF creation was related to 53% higher mortality in the subsequent 6 months. LIMITATIONS: Residual confounding. CONCLUSIONS: Our findings highlight the need to reevaluate practices for optimizing long-term access planning and achievable AVF outcomes, especially AVF maturation. New AVFs that are not successfully used are associated with long-term catheter exposure and elevated mortality risk. These findings highlight the importance of selecting the best access type for each patient and developing effective clinical pathways for when AVFs fail to mature successfully.

Estimation of Prevalence of Kidney Disease Treated With Dialysis in China: A Study of Insurance Claims Data.

RATIONALE & OBJECTIVE: The national prevalence of dialysis in China has not been well studied. We aimed to estimate the prevalence of kidney disease treated with dialysis and predict the trend using claims data in order to provide evidence for developing prevention strategies. STUDY DESIGN: Cross-sectional study of insurance claims. SETTING & PARTICIPANTS: Medical claims data from January 1, 2013, to December 31, 2017, were extracted from a large claims database by using a 2-stage sampling design to obtain a national sample covered by the urban basic medical insurance, the most predominant insurance program in China. EXPOSURE: Patients receiving maintenance dialysis, including hemodialysis (HD) and peritoneal dialysis (PD), were identified according to medical billing data and International Classification of Diseases, Tenth Revision (ICD-10) codes. OUTCOMES: The age- and sex-standardized population prevalence of kidney disease treated with dialysis was estimated by year and treatment modality. ANALYTICAL APPROACH: Crude and age- and sex-standardized prevalence of kidney disease treated with dialysis were calculated stratified by year and treatment modality. The gray Verhulst model was used to predict dialysis prevalence from 2018 to 2025. RESULTS: The age-and sex-standardized prevalence of dialysis patients increased from 255.11 per million population (pmp) in 2013 to 419.39 pmp in 2017. The age- and sex-standardized prevalence of HD and PD in 2017 were 384.41 pmp and 34.98 pmp, respectively, and the total number of dialysis patients in China was estimated to be 581,273. The prevalence of dialysis was predicted to rise above 2017 levels, with a predicted prevalence of 534.60 pmp in 2020 and 629.67 pmp in 2025, corresponding to 744,817 and 874,373 patients, respectively. LIMITATIONS: Claims data have potential errors in classification of patients, and population selection bias may have limited inferences to the entire Chinese population. CONCLUSIONS: The prevalence of kidney disease treated with dialysis has risen between 2013 and 2017 in China and is predicted to increase further through 2025. These findings highlight the importance of prevention and control strategies to reduce the escalating burden of kidney failure.