Regression of left ventricular mass following conversion from conventional hemodialysis to thrice weekly in-centre nocturnal hemodialysis

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).

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).

Cardiovascular Benefits of Extended-Time Nocturnal Hemodialysis

Hemodialysis (HD) remains the most utilized treatment for End-Stage Kidney Disease (ESKD) globally, mainly as conventional HD administered in 4 h sessions thrice weekly. Despite advances in HD delivery, patients with ESKD carry a heavy cardiovascular morbidity and mortality burden. This is associated with cardiac remodeling, left ventricular hypertrophy (LVH), myocardial stunning, hypertension, decreased heart rate variability, sleep apnea, coronary calcification and endothelial dysfunction. Therefore, intensive HD regimens closer to renal physiology were developed. They include longer, more frequent dialysis or both. Among them, Nocturnal Hemodialysis (NHD), carried out at night while asleep, provides efficient dialysis without excessive interference with daily activities. This regimen is closer to the physiology of the native kidneys. By providing increased clearance of small and middle molecular weight molecules, NHD can ameliorate uremic symptoms, control hyperphosphatemia and improve quality of life by allowing a liberal diet and free time during the day. Lastly, it improves reproductive biology leading to successful pregnancies. Conversion from conventional to NHD is followed by improved blood pressure control with fewer medications, regression of LVH, improved LV function, improved sleep apnea, and stabilization of coronary calcifications. These beneficial effects have been associated, among others, with better extracellular fluid volume control, improved endothelial- dependent vasodilation, decreased total peripheral resistance, decreased plasma norepinephrine levels and restoration of heart rate variability. Some of these effects represent improvements in outcomes used as surrogates of hard outcomes related to cardiovascular morbidity and mortality. In this review, we consider the cardiovascular effects of NHD.

Technique Survival and Determinants of Technique Failure in In-Center Nocturnal Hemodialysis: A Retrospective Observational Study

Background

Long-duration (7-8 hours) hemodialysis provides benefits compared with conventional thrice-weekly, 4-hour sessions. Nurse-administered, in-center nocturnal hemodialysis (INHD) may expand the population to whom an intensive dialysis schedule can be offered.

Objective

The primary objective of this study was to determine predictors of INHD technique failure, disruptions, and technique survival.

Design

This study used retrospective chart and database review methodology.

Setting

This study was conducted at a single Canadian INHD program operating in Victoria, British Columbia, within a tertiary care hospital. Our program serves a catchment population of approximately 450 000 people.

Patients/Sample/Participants

Forty-three consecutive incident INHD patients took part in the INHD program of whom 42 provided informed consent to participate in this study.

Methods

We conducted a retrospective observational study including incident INHD patients from 2015 to 2017. The primary outcome was technique failure ≤6 months (TF ≤6). Secondary outcomes included technique survival and reasons for/predictors of INHD discontinuation or temporary disruption. Predictors of each outcome included demographics, comorbidities, and Clinical Frailty Scale (CFS) scoring.

Results

Among 42 patients, mean (SD) age, dialysis vintage, CFS score, and follow-up were 63 (16) years, 46 (55) months, 4 (1), and 11 (9) months, respectively. 52% were aged ≥65 years. TF ≤6 occurred in 12 (29%) patients. One-year technique survival censored for transplants and home dialysis transitions was 60%. Discontinuation related to insomnia (32%), medical status change (27%), and vascular access (23%). In unadjusted Cox survival analysis, 1-point increases in CFS score associated with a higher risk of technique failure (hazard ratio: 2.04, 95% confidence interval [CI]: 1.26-3.31). In an adjusted analysis, higher frailty severity also associated with temporary INHD disruptions (incidence rate ratio: 2.64, 95% CI: 1.55-4.50, comparing CFS of ≥4 to 1-3).

Limitations

The retrospective, observational design of this study resulted in limited ability to control for confounding factors. In addition, the relatively small number of events observed owing to a small sample size diminished statistical power to inform study conclusions. Use of a single physician to determine the clinical frailty score is another limitation. Finally, the use of a single center for this study limits generalizability to other programs and clinic settings.

Conclusions

INHD is a sustainable modality, even among older patients. Higher frailty associates with INHD technique failure and greater missed treatments. Inclusion of a CFS threshold of ≤4 into INHD inclusion criteria may help to identify individuals most likely to realize the long-term benefits of INHD.

Trial Registration

Due to the retrospective and observational design of this study, trial registration was not necessary.

Dietary intake, clinical-nutritional status, and homocysteine in hemodialysis subjects: the mediating role of inflammation (NUGE-HD study)

The aim of the present study was to test the hypothesis that inflammation mediates the associations among food intake, clinical-nutritional status, and plasma homocysteine (Hcys) in hemodialysis (HD) subjects. This was a cross-sectional analysis of data on 129 subjects undergoing HD (58.9% male, 61.8 ± 15.5 years of age) from the cohort Nutrition and Genetics on HD outcomes (NUGE-HD study). Sociodemographic, anthropometric, and metabolic data were collected, and food intake was assessed using a quantitative food frequency questionnaire. Plasma C-reactive protein (CRP) was used as an inflammatory marker. Data were analyzed by structural equation modeling. Regarding the direct effects, complex B vitamin intake was negatively associated with body mass index, and diabetes mellitus was positively associated with CRP. Plasma CRP also showed a negative association with Hcys, and the ratio of saturated and polyunsaturated fatty acids intake showed a positive association with Hcys. Regarding indirect effects, the results showed that the relationship between the presence of diabetes mellitus and Hcys is mediated by plasma CRP. In conclusion, the ratio of saturated and polyunsaturated fatty acids had a direct effect on plasma Hcys, whereas inflammation had a direct and mediating effect on the relationship between Hcys and diabetes mellitus in HD subjects. Novelty In end-stage renal disease, CRP influences plasma Hcys directly and also indirectly through its mediating effect. The quantity and quality of dietary fatty acids influence plasma Hcys concentrations in HD subjects.

Association between conversion to in-center nocturnal hemodialysis and right ventricular remodeling

Background

In-center nocturnal hemodialysis (INHD) is associated with favorable left ventricular (LV) remodeling. Although right ventricular (RV) structure and function carry prognostic significance, the impact of dialysis intensification on RV is unknown. Our objectives were to evaluate changes in RV mass index (MI), end-diastolic volume index (EDVI), end-systolic volume index (ESVI) and ejection fraction (EF) after conversion to INHD and their relationship with LV remodeling.

Methods

Of 67 conventional hemodialysis (CHD, 4 h/session, three times/week) patients, 30 continued on CHD and 37 converted to INHD (7-8 h/session, three times/week). Cardiac magnetic resonance imaging was performed at baseline and 1 year using a standardized protocol; an experienced and blinded reader performed RV measurements.

Results

At 1 year there were significant reductions in RVMI {-2.1 g/m2 [95% confidence interval (CI) -3.8 to - 0.4], P = 0.017}, RVEDVI [-9.5 mL/m2 (95% CI - 16.3 to - 2.6), P = 0.008] and RVESVI [-6.2 mL/m2 (95% CI - 10.9 to - 1.6), P = 0.011] in the INHD group; no significant changes were observed in the CHD group. Between-group comparisons showed significantly greater reduction of RVESVI [-7.9 mL/m2 (95% CI - 14.9 to - 0.9), P = 0.03] in the INHD group, a nonsignificant trend toward greater reduction in RVEDVI and no significant difference in RVMI and RVEF changes. There was significant correlation between LV and RV in terms of changes in mass index (MI) (r = 0.46), EDVI (r = 0.73), ESVI (r = 0.7) and EF (r = 0.38) over 1 year (all P < 0.01).

Conclusions

Conversion to INHD was associated with a significant reduction of RVESVI. Temporal changes in RV mass, volume and function paralleled those of LV. Our findings support the need for larger, longer-term studies to confirm favorable RV remodeling and determine its impact on clinical outcomes.

Nocturnal hemodialysis: improved quality of life and patient outcomes

Conventional hemodialysis is associated with high morbidity and mortality rates, as well as a reduced quality of life. There is a growing interest in the provision of more intensive hemodialysis, due to associated benefits in terms of reduced cardiovascular morbidity, better regulation of mineral metabolism, as well as its impact on quality of life measures, fertility, and sleep. Nocturnal hemodialysis, both in center and at home, allows the delivery of more intensive hemodialysis. This review discusses the benefits of nocturnal hemodialysis and evaluates the evidence based on available literature.

Cardiovascular magnetic resonance left ventricular strain in end-stage renal disease patients after kidney transplantation

BACKGROUND

Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function.

METHODS

We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12 months after KT.

RESULTS

Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p = 0.007) and global radial strain (GRS) (p = 0.003), but a decline in global longitudinal strain (GLS) over 12 months (p = 0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4 ± 6.4% at baseline, 60.6% ± 6.9% at 12 months; p = 0.001). For entire cohort, over 12 months, change in LVEF was significantly correlated with change in GCS (Spearman's r = - 0.42, p < 0.001), GRS (Spearman's r = 0.64, p < 0.001), and GLS (Spearman's r = - 0.34, p = 0.002). Improvements in GCS and GRS over 12 months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p < 0.05), but not with change in blood pressure (all p > 0.10).

CONCLUSIONS

Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12 months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.

Determinants of Left Ventricular Characteristics Assessed by Cardiac Magnetic Resonance Imaging and Cardiovascular Biomarkers Related to Kidney Transplantation

Background:

Cardiac magnetic resonance (CMR) imaging accurately and precisely measures left ventricular (LV) mass and function. Identifying mechanisms by which LV mass change and functional improvement occur in some end-stage kidney disease (ESKD) patients may help to appropriately target kidney transplant (KT) recipients for further investigation and intervention. The concentration of serum adiponectin, a cardiovascular biomarker, increases in cardiac failure, its production being enhanced by B-type natriuretic peptide (BNP), and both serum adiponectin and BNP concentrations decline posttransplantation.

Objective:

We tested the hypothesis that kidney transplantation alters LV characteristics that relate to serum adiponectin concentrations.

Design:

Prospective and observational cohort study.

Setting:

The study was performed at 3 adult kidney transplant and dialysis centers in Ontario, Canada.

Patients:

A total of 82 KT candidate subjects were recruited (39 to the KT group and 43 to the dialysis group). Predialysis patients were excluded.

Measurements:

Subjects underwent CMR with a 1.5-tesla whole-body magnetic resonance scanner using a phased-array cardiac coil and retrospective vectorographic gating. LV mass, LV ejection fraction (LVEF), LV end-systolic volume (LVESV), and LV end-diastolic volume (LVEDV) were measured by CMR pre-KT and again 12 months post-KT (N = 39), or 12 months later if still receiving dialysis (N = 43). LV mass, LVESV, and LVEDV were indexed for height (m^2.7) to calculate left ventricular mass index (LVMI), left ventricular end-systolic volume index (LVESVI), and left ventricular end-diastolic volume index (LVEDVI), respectively. Serum total adiponectin and N-terminal proBNP (NT-proBNP) concentrations were measured at baseline, 3 months, and 12 months.

Methods:

We performed a prospective 1:1 observational study comparing KT candidates with ESKD either receiving a living donor organ (KT group) or waiting for a deceased donor organ (dialysis group).

Results:

Left ventricular mass index change was −1.98 ± 5.5 and −0.36 ± 5.7 g/m^2.7 for KT versus dialysis subjects (P = .44). Left ventricular mass change was associated with systolic blood pressure (SBP) (P = .0008) and average LV mass (P = .0001). Left ventricular ejection fraction did not improve (2.9 ± 6.6 vs 0.7 ± 4.9 %, P = .09), while LVESVI and LVEDVI decreased more post-KT than with continued dialysis (−3.36 ± 5.6 vs −0.22 ± 4.4 mL/m^2.7, P < .01 and −4.9 ± 8.5 vs −0.3 ± 9.2 mL/m^2.7, P = .02). Both adiponectin (−7.1 ± 11.3 vs −0.11 ± 7.9 µg/mL, P < .0001) and NT-proBNP (−3811 ± 8130 vs 1665 ± 20013 pg/mL, P < .0001) declined post-KT. Post-KT adiponectin correlated with NT-proBNP (P = .001), but not estimated glomerular filtration rate (eGFR) (P = .13). Change in adiponectin did not correlate with change in LVEF in the KT group (Spearman ρ = 0.16, P = .31) or dialysis group (Spearman ρ = 0.19, P = .21).

Limitations:

Few biomarkers of cardiac function were measured to fully contextualize their role during changing kidney function. Limited intrapatient biomarker sampling and CMR measurements precluded constructing dose-response curves of biomarkers to LV mass and function. The CMR timing in relation to dialysis was not standardized.

Conclusions:

The LVESVI and LVEDVI but not LVMI or LVEF improve post-KT. LVMI and LVEF change is independent of renal function and adiponectin. As adiponectin correlates with NT-proBNP post-KT, improved renal function through KT restores the normal heart-endocrine axis.

Phosphate Removal During Long Nocturnal Hemodialysis/Hemodiafiltration: A Study With Total Dialysate Collection

The aim of our prospective study was to quantify phosphate removal during long nocturnal high-flux hemodialysis or hemodiafiltration (HD) with total dialysate collection. Eight patients (two women) were studied for the first-in-the-week HD session that lasted 7-8 h. Total dialysate was collected. Serum and collected dialysate phosphate concentrations were measured every hour. Phosphate removal as assessed from the serum concentration was most important during the first 2 h of HD, and then a plateau was reached. The highest average phosphate concentration in the total dialysate was in the 1(st) hour, thereafter the concentration decreased but remained stable. The average total removed mass of phosphate quantified from hourly collected dialysate was 5195.7 ± 1898 mg. Phosphate had been removed in a consistent manner during the whole duration of nocturnal HD as assessed through dialysate (despite stable serum phosphate concentration). This could indicate phosphate transfer from intracellular space. The total removed phosphate quantified from the total dialysate collection was higher than previously reported and exceeded the normal phosphate food intake.

In-Center Nocturnal Hemodialysis Versus Conventional Hemodialysis: A Systematic Review of the Evidence

BACKGROUND

Owing to its longer treatment duration-up to 8 hours per dialysis treatment-in-center thrice-weekly nocturnal hemodialysis (HD) is receiving greater attention. To better understand the evidence for in-center nocturnal HD, we sought to systematically review the literature to determine the effects of in-center nocturnal HD versus conventional HD on clinically relevant outcomes.

STUDY DESIGN

We searched MEDLINE, Embase, Evidence-Based Medicine Reviews (EBMR), Web of Science, and Scopus from the earliest date in the database to November 2016.

SETTING & POPULATION

Adults receiving in-center nocturnal HD compared with those receiving conventional HD.

SELECTION CRITERIA FOR STUDIES

All quasi-experimental and observational studies were considered; randomized trials were sought but not found.

PREDICTOR

Nocturnal vs conventional in-center HD.

OUTCOMES

Indexes of blood pressure and left ventricular hypertrophy, markers of anemia, measures of bone mineral metabolism, nutrition, quality of life, sleep quality, episodes of intradialytic hypotension, hospitalization, and mortality.

RESULTS

Of 2,086 identified citations, 21 met the inclusion criteria, comprising a total of 1,165 in-center nocturnal HD patients and 15,865 conventional HD patients. Although there was substantial heterogeneity in reporting of outcomes, we pooled data for measures of blood pressure, anemia, and mineral metabolism. Though heterogeneity was generally high, in-center nocturnal HD was associated with improved systolic blood pressure (-3.18 [95% CI, -5.58 to -0.78) mm Hg, increased hemoglobin levels (0.53 [95% CI, 0.11-0.94] g/dL), and lower serum phosphate levels (-0.97 [95% CI, -1.48 to -0.46] mg/dL).

LIMITATIONS

No randomized trials have been conducted to address the clinical effects of in-center nocturnal HD. The quality of the observational literature contributing to the results of this review was generally poor to moderate. Confounded outcomes are a significant concern. Publication bias and outcome reporting bias remain possibilities.

CONCLUSIONS

Relative to conventional HD, in-center nocturnal HD was associated with improvements in several clinically relevant outcomes. Other benefits may not have been detected due to small sample sizes of included studies; no prespecified outcome was worse with in-center nocturnal HD.

Extended-hours hemodialysis is associated with lower mortality risk in patients with end-stage renal disease

Extended-hours hemodialysis offers substantially longer treatment time compared to conventional hemodialysis schedules and is associated with improved fluid and electrolyte control and favorable cardiac remodeling. However, whether extended-hours hemodialysis improves survival remains unclear. Therefore, we determined the association between extended-hours compared to conventional hemodialysis and the risk of all-cause mortality in a nationally representative cohort of patients initiating maintenance dialysis in the United States from 2007 to 2011. Survival analyses using causal inference modeling with marginal structural models were performed to compare mortality risk among 1206 individuals undergoing thrice weekly extended-hours hemodialysis or 111,707 patients receiving conventional hemodialysis treatments. The average treatment time per session for extended-hours hemodialysis was 399 minutes compared to 211 minutes for conventional therapy. The crude mortality rate with extended-hours hemodialysis was 6.4 deaths per 100 patient-years compared with 14.7 deaths per 100 patient-years for conventional hemodialysis. In the primary analysis, patients treated with extended-hours hemodialysis had a 33% lower adjusted risk of death compared to those who were treated with a conventional regimen (95% confidence interval: 7% to 51%). Additional analyses accounting for analytical assumptions regarding exposure and outcome, facility-level confounders, and prior modality history were similar. Thus, in this large nationally representative cohort, treatment with extended-hours hemodialysis was associated with a lower risk for mortality compared to treatment with conventional in-center therapy. Adequately powered randomized clinical trials comparing extended-hours to conventional hemodialysis are required to confirm these findings.

Investigating the effects of 6 months extended duration, in-centre nocturnal versus conventional haemodialysis treatment: a non-randomised, controlled feasibility study

INTRODUCTION

In-centre nocturnal haemodialysis (INHD) is an underutilised dialysis regimen that can potentially provide patients with better clinical outcomes due to extended treatment times. We have established an INHD programme within our clinical network, fulfilling a previously unmet patient need. This feasibility study aims to gather sufficient data on numerous outcome measures to inform the design of a multicentre randomised controlled trial that will establish the potential benefits of INHD and increase the availability of this service nationally and internationally.

METHODS AND ANALYSIS

This will be a non-randomised controlled study. Prevalent patients on haemodialysis (HD) will electively change from a conventional in-centre HD regimen of 4 hours thrice weekly to a regimen of extended treatment times (5-8 hours) delivered in-centre overnight thrice weekly. After recruitment of the INHD cohort, a group of patients matched for age, gender and dialysis vintage will be selected from patients remaining on a conventional daytime dialysis programme. Outcome measures will include left ventricular mass as measured by MRI, physical performance measured by the short physical performance battery and physical activity measured by accelerometry. Additionally we will measure quality of life using validated questionnaires, nutritional status by bioimpedance spectroscopy and food diaries, and blood sampling for markers of cardiovascular disease, systemic inflammation. Suitable statistical tests shall be used to analyse the data. We will use omnibus tests to observe changes over the duration of the intervention and between groups. We will also look for associations between outcome measures that may warrant further investigation. These data will be used to inform the power calculation for future studies.

ETHICS AND DISSEMINATION

A favourable opinion was granted by Northampton Research Ethics Committee (15/EM/0268). It is anticipated that results of this study will be presented at national and international meetings, with reports being published in journals during 2017.

TRIAL REGISTRATION NUMBER

ISRCTN16672784.

Reduction of carbamylated albumin by extended hemodialysis

Introduction Among conventional hemodialysis (CHD) patients, carbamylated serum albumin (C-Alb) correlates with urea and amino acid deficiencies and is associated with mortality. We postulated that reduction of C-Alb by intensive HD may correlate with improvements in protein metabolism and cardiac function. Methods One-year observational study of in-center nocturnal extended hemodialysis (EHD) patients and CHD control subjects. Thirty-three patients receiving 4-hour CHD who converted to 8-hour EHD were enrolled, along with 20 controls on CHD. Serum C-Alb, biochemistries, and cardiac MRI parameters were measured before and after 12 months of EHD. Findings EHD was associated with reduction of C-Alb (average EHD change -3.20 mmol/mol [95% CI -4.23, -2.17] compared to +0.21 [95% CI -1.11, 1.54] change in CHD controls, P < 0.001). EHD was also associated with increases in average essential amino acids (in standardized units) compared to CHD (+0.38 [0.08, 0.68 95%CI]) vs. -0.12 [-0.50, 0.27, 95% CI], P = 0.047). Subjects who reduced C-Alb more than 25% were found to have reduced left ventricular mass, increased urea reduction ratio, and increased serum albumin compared to nonresponders, and % change in C-Alb significantly correlated with % change in left ventricular mass. Discussion EHD was associated with reduction of C-Alb as compared to CHD, and reduction of C-Alb by EHD correlates with reduction of urea. Additional studies are needed to test whether reduction of C-Alb by EHD also correlates with improved clinical outcomes.

A 4-month programme of in-centre nocturnal haemodialysis was associated with improvements in patient outcomes

BACKGROUND

Extended periods of haemodialysis (HD) can improve patient outcomes. In-centre nocturnal haemodialysis (INHD) should be explored as a method of offering extended periods of HD to patients unsuitable for or unable to perform home therapy.

METHODS

Ten self-selecting, prevalent HD patients started an INHD programme to assess feasibility and patient satisfaction. Quality-of-life (QOL) measures were evaluated at enrolment and after 4 months of INHD using the EQ-5D, the Hospital Anxiety and Depression Scale (HADS) and the SF-12 questionnaires. Demographic, biochemical and haematological data and data on dialysis adequacy were collected before starting INHD and after 4 months.

RESULTS

Three of the 10 patients failed to complete the 2-week run-in period. Seven patients completed the 4-month programme, with mean dialysis time of 355 ± 43.92 min throughout the period. The EQ-5D visual analogue score improved from 48 ± 16.89 to 72 ± 13.2 (P = 0.003) and the HADS anxiety score decreased from 9 ± 5.83 to 3.57 ± 3.04 (P = 0.029). The urea reduction ratio improved from 71.57 ± 2.29% to 80.43 ± 3.101% (P < 0.001), with improvements in phosphate control, reducing to within the target range from 1.73 ± 0.6 to 1.2 ± 0.2 (P = 0.08). Ultrafiltration (UF) volumes increased during the study from 2000 ± 510 to 2606 ± 343 mL (P = 0.015); there was a significant reduction in mean UF rate adjusted for body weight from 6.47 ± 1.71 to 4.61 ± 1.59 mL/kg/h (P = 0.032). Sensitivity analyses confirmed the significance of these results.

CONCLUSIONS

This single-centre study showed a 4-month programme of extended hours INHD is safe and associated with improvements in QOL measures, decreased UF rates and measures of dialysis adequacy. These data have been used to expand our service and inform the design of future randomized controlled trials to examine medical endpoints.

In-center nocturnal hemodialysis

Dialysis intensification from conventional regimens (typically thrice weekly, 4 hours per session) is increasingly utilized with the intent of improving the cardiovascular health and quality of life of chronic dialysis recipients. While home nocturnal hemodialysis offers the opportunity for maximal intensification of dialysis, it is inaccessible to the majority of dialysis recipients who are unable to self-administer hemodialysis in their own homes. In-center nocturnal hemodialysis (INHD) permits the intensification of conventional hemodialysis with the benefits of nursing support and supervision in addition to freedom from dialysis during productive daytime hours. Although no randomized trials have evaluated the relative merits of INHD, preliminary data indicate that INHD is a viable option that may confer a variety of benefits for chronic dialysis recipients.

Cost analysis of in-centre nocturnal compared with conventional hemodialysis

Background

Provision of in-centre nocturnal hemodialysis (ICNHD; 6–8 hours thrice weekly) is associated with health benefits, but the economic implications of providing this treatment are unclear.

Objective

We conducted a health care costing study comparing ICNHD to in-centre thrice-weekly conventional hemodialysis (CvHD).

Design

Micro-costing of both ICNHD and CvHD as practiced at our centre.

Setting

Hemodialysis unit at a tertiary-care hospital in Edmonton.

Participants

An informal survey of 2 other Canadian ICNHD programs was conducted to inform practices that may deviate from ours to guide sensitivity analysis.

Measurements

Resources consumed for each strategy were determined, and the cost of each unit (CAN $2012) was used to calculate incremental costs of ICNHD and CvHD.

Methods

We focused on resources that differ between strategies (staffing, dialysis materials, and utilities). The reference case considered 1:3 staff to patient ratio; alternate scenarios explored nursing pay grade and ratio, full care vs. self-care dialysis (including training costs), and medication costs.

Results

In the reference case, ICNHD was $61 more costly per dialysis treatment compared with CvHD ($9,538 per patient per year). Incremental annual costs for staffing, dialysis materials, and utilities were $8,201, $1,193, and $144, respectively. If ICNHD reduces medication use (anti-hypertensives, bone mineral metabolism medications), the incremental cost of ICNHD decreases to $8,620 per patient per year. In a scenario of self-care ICNHD utilizing a staff-to-patient ratio of 1:10, ICNHD is more costly in year 1 ($15,196), but results in cost savings of $2,625 in subsequent years compared with CvHD.

Limitations

The findings of this cost analysis may not be generalizable to other health care systems, including other parts of Canada.

Conclusions

Compared to CvHD, provision of ICNHD is more expensive, largely driven by increased staffing costs as patients dialyze longer. Alternate staffing models, including self-care ICNHD with minimal staff, may lead to net cost savings. The incremental cost of treatment should be considered in the context of impact on patient health outcomes, staffing model, and pragmatic factors, such as current capacity for daytime CvHD and the capital costs of new dialysis stations.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-3581-1-14) contains supplementary material, which is available to authorized users.

Fibroblast growth factor 23 and left ventricular mass index in maintenance hemodialysis patients: standard versus long nocturnal hemodialysis

Elevated levels of fibroblast growth factor 23 (FGF23) and phosphorus (P) have been linked to greater risks of left ventricular hypertrophy (LVH) in patients with end stage renal disease (ESRD). The aim of this study was to test if differences exist in a long nocturnal HD group in comparison with a group treated with standard daily thrice weekly dialysis. The attempt was to evaluate if elevated FGF-23 levels, intact parathyroid hormone and P might be associated with left ventricular mass index (LVMI). Quantitative echocardiographic analyses were performed at baseline in 50 maintenance HD patients (17 women and 33 men, mean age: 56.4 ± 15.35 years, mean HD vintage: 9.06 ± 8.86 years, all patients are on HD thrice a week-median duration 15 h/week, 10 of them on long nocturnal HD, median duration 24 h/week). LVMIs were calculated. FGF23 was measured in duplicate using a second generation C-terminal enzyme-linked immunosorbent assay and log of FGF-23 values were computed. Mean LVMI was 136.44 ± 44.44 g/m(2) . Serum FGF-23 levels were elevated when compared to population data with preserved kidney function (median 1388.5 RU/mL, range 252 to 24 336 RU/mL). There were no correlations recorded between log FGF-23 levels and LVMI (r = 0.2, P = 0.66). LVMI was significantly lower in HD patients on long nocturnal dialysis procedure (r = -0.31, P = 0.05). Patients treated with long nocturnal HD showed lower LV mass, lower P-values and higher 25-OH-D3 supply. Plasma FGF-23 concentration was comparable between the groups and was not associated with LVMI in our maintenance HD patients.

Rationale and design of the Sodium Lowering In Dialysate (SoLID) trial: a randomised controlled trial of low versus standard dialysate sodium concentration during hemodialysis for regression of left ventricular mass

BACKGROUND

The current literature recognises that left ventricular hypertrophy makes a key contribution to the high rate of premature cardiovascular mortality in dialysis patients. Determining how we might intervene to ameliorate left ventricular hypertrophy in dialysis populations has become a research priority. Reducing sodium exposure through lower dialysate sodium may be a promising intervention in this regard. However there is clinical equipoise around this intervention because the benefit has not yet been demonstrated in a robust prospective clinical trial, and several observational studies have suggested sodium lowering interventions may be deleterious in some dialysis patients.

METHODS/DESIGN

The Sodium Lowering in Dialysate (SoLID) study is funded by the Health Research Council of New Zealand. It is a multi-centre, prospective, randomised, single-blind (outcomes assessor), controlled parallel assignment 3-year clinical trial. The SoLID study is designed to study what impact low dialysate sodium has upon cardiovascular risk in dialysis patients. The study intends to enrol 118 home hemodialysis patients from 6 sites in New Zealand over 24 months and follow up each participant over 12 months. Key exclusion criteria are: patients who dialyse more frequently than 3.5 times per week, pre-dialysis serum sodium of <135 mM, and maintenance hemodiafiltration. In addition, some medical conditions, treatments or participation in other dialysis trials, which contraindicate the SoLID study intervention or confound its effects, will be exclusion criteria. The intervention and control groups will be dialysed using dialysate sodium 135 mM and 140 mM respectively, for 12 months. The primary outcome measure is left ventricular mass index, as measured by cardiac magnetic resonance imaging, after 12 months of intervention. Eleven or more secondary outcomes will be studied in an attempt to better understand the physiologic and clinical mechanisms by which lower dialysate sodium alters the primary end point.

DISCUSSION

The SoLID study is designed to clarify the effect of low dialysate sodium upon the cardiovascular outcomes of dialysis patients. The study results will provide much needed information about the efficacy of a cost effective, economically sustainable solution to a condition which is curtailing the lives of so many dialysis patients.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry number: ACTRN12611000975998.

Current state of intensive hemodialysis: a comparative review of benefits and barriers

The current interest in intensive hemodialysis (HD) was born out of the impasse in an effort to improve survival and quality of life (QOL) in patients with end-stage renal disease. In this review, we have summarized the emerging data of intensive HD on (i) survival, (ii) cardiovascular outcomes, (iii) phosphate balance and (iv) QOL. Although there is a consistent and compelling signal favoring intensive HD, it is important to balance the enthusiasm with the significant amount of perceived and actual barriers for our patients to overcome to receive or perform intensive HD. For an individual patient, the answer to the question 'What is the best form of intensive hemodialysis?' should be a consideration between the benefits sought and the obstacles in attaining intensive HD. In the future, changes in dialysis technology, healthcare delivery and education strategy are needed to allow the majority of patients to receive optimal renal replacement therapy.