Effects of low-flux and high-flux hemodialysis on the survival of elderly maintenance hemodialysis patients

BACKGROUND

Elderly hemodialysis (HD) patients have a high risk of death. The effect of different types of HD membranes on survival is still controversial. The purpose of this study was to determine the relationship between the use of low-flux or high-flux membranes and all-cause and cardiovascular mortality in elderly hemodialysis patients.

METHODS

This was a retrospective clinical study involving maintenance hemodialysis patients which were categorized into low-flux and high-flux groups according to the dialyzer they were using. Propensity score matching was used to balance the baseline data of the two groups. Survival rates were compared between the two groups, and the risk factors for death were analyzed by multivariate Cox regression.

RESULTS

Kaplan-Meier survival analysis revealed no significant difference in all-cause mortality between the low-flux group and the high-flux group (log-rank test, p = 0.559). Cardiovascular mortality was significantly greater in the low-flux group than in the high-flux group (log-rank test, p = 0.049). After adjustment through three different multivariate models, we detected no significant difference in all-cause mortality. Patients in the high-flux group had a lower risk of cardiovascular death than did those in the low-flux group (HR = 0.79, 95% CI, 0.54-1.16, p = 0.222; HR = 0.58, 95% CI, 0.37-0.91, p = 0.019).

CONCLUSIONS

High-flux hemodialysis was associated with a lower relative risk of cardiovascular mortality in elderly MHD patients. High-flux hemodialysis did not improve all-cause mortality rate. Differences in urea distribution volume, blood flow, and systemic differences in solute clearance by dialyzers were not further analyzed, which are the limitations of this study.

Intérêts et limites de l’Hémodialyse Longue Nocturne

L’hémodialyse (HD) Longue Nocturne (HDLN) intermittente permet de combiner dialyse et sommeil. Ses avantages cliniques sont une vitesse d’ultrafiltration réduite, un meilleur contrôle de la volémie avec amélioration de la tolérance des séances et des performances cardiaques, une phosphatémie et des moyennes molécules mieux épurées et une meilleure survie dans les études de cohortes. La qualité de vie n’est pas altérée par la longueur des séances et elle s’améliore quand elle n’est pas optimale lors du transfert de l’HD standard vers l’HDLN. La qualité du sommeil n’est parfois perturbée mais elle n’est pas une cause importante de sortie du programme. La pérennité d’un programme d’HDLN passe par les volontés conjointes médicales et managériales, la sélection des patients stables, le respect des horaires et de la durée de séances, indispensable à la dialyse de sommeil. Les autorités de santé doivent jouer un rôle pour permettre cette modalité dans des conditions financières acceptables. L’information au patient de l’existence de l’HDLN avant le stade de la dialyse est essentielle, aidée par le témoignage des pairs. Les sociétés savantes doivent soutenir la recherche et l’information aux néphrologues. Enfin les conditions architecturales favorisant l’intimité et le sommeil sont une clé de réussite du programme.

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).

Reduction of protein-bound uraemic toxins in plasma of chronic renal failure patients: A systematic review

BACKGROUND

Protein-bound uraemic toxins (PBUTs) accumulate in patients with chronic kidney disease and impose detrimental effects on the vascular system. However, a unanimous consensus on the most optimum approach for the reduction of plasma PBUTs is still lacking.

METHODS

In this systematic review, we aimed to identify the most efficient clinically available plasma PBUT reduction method reported in the literature between 1980 and 2020. The literature was screened for clinical studies describing approaches to reduce the plasma concentration of known uraemic toxins. There were no limits on the number of patients studied or on the duration or design of the studies.

RESULTS

Out of 1274 identified publications, 101 studies describing therapeutic options aiming at the reduction of PBUTs in CKD patients were included in this review. We stratified the studies by the PBUTs and the duration of the analysis into acute (data from a single procedure) and longitudinal (several treatment interventions) trials. Reduction ratio (RR) was used as the measure of plasma PBUTs lowering efficiency. For indoxyl sulphate and p-cresyl sulphate, the highest RR in the acute studies was demonstrated for fractionated plasma separation, adsorption and dialysis system. In the longitudinal trials, supplementation of haemodialysis patients with AST-120 (Kremezin®) adsorbent showed the highest RR. However, no superior method for the reduction of all types of PBUTs was identified based on the published studies.

CONCLUSIONS

Our study shows that there is presently no technique universally suitable for optimum reduction of all PBUTs. There is a clear need for further research in this field.

Effect of changing treatment to high-flux hemodialysis (HFHD) on mortality in patients with long-term low flux hemodialysis (LFHD): a propensity score matched cohort study

Background

The purpose of this study was to explore the effect of changing treatment to high-flux hemodialysis (HFHD) on mortality rate in patients with long-term low flux hemodialysis (LFHD).

Methods

The patients with end-stage renal disease (ESRD) who underwent LFHD with dialysis age more than 36 months and stable condition in our hospital before December 31, 2014 were included in this study. They were divided into control group and observation group. Propensity score matched method was used to select patients in the control group. The hemodialysis was performed 3 times a week for 4 h. The deadline for follow-up is December 31, 2018. End-point event is all-cause death. The survival rates of the two groups were compared and multivariate Cox regression analysis was carried out.

Results

K-M survival analysis showed that the 1-year, 2-year, 3-year and 4-year survival rates of HFHD group were 98, 96, 96 and 96%, respectively. The 1-year, 2-year, 3-year and 4-year survival rates of LFHD group were 95, 85, 80 and 78%, respectively. Log-rank test showed that the survival rate of HFHD group was significantly higher than that of LFHD group (x²= 7.278, P = 0.007). Multivariate Cox regression analysis showed that male, age, hemoglobin and low-throughput dialysis were independent predictors of death (P < 0.05). Compared with LFHD, HFHD can significantly reduce the mortality risk ratio of patients, as high as 86%.

Conclusion

The prognosis of patients with ESRD who performed long-term LFHD can be significantly improved after changing to HFHD.

Clinical Interventions and All-Cause Mortality of Patients with Chronic Kidney Disease: An Umbrella Systematic Review of Meta-Analyses

Patients with chronic kidney disease (CKD) have altered physiologic processes, which result in different treatment outcomes compared with the general population. We aimed to systematically evaluate the efficacy of clinical interventions in reducing mortality of patients with CKD. We searched PubMed, MEDLINE, Embase, and Cochrane Database of Systematic Reviews for meta-analyses of randomized controlled trials (RCT) or observational studies (OS) studying the effect of treatment on all-cause mortality of patients with CKD. The credibility assessment was based on the random-effects summary estimate, heterogeneity, 95% prediction intervals, small study effects, excess significance, and credibility ceilings. Ninety-two articles yielded 130 unique meta-analyses. Convincing evidence from OSs supported mortality reduction with three treatments: angiotensin-converting-enzyme inhibitors or angiotensin II receptor blockers for patients not undergoing dialysis, warfarin for patients with atrial fibrillation not undergoing dialysis, and (at short-term) percutaneous coronary intervention compared to coronary artery bypass grafting for dialysis patients. Two treatment comparisons were supported by highly credible evidence from RCTs in terms of all-cause mortality. These were high-flux hemodialysis (HD) versus low-flux HD as a maintenance HD method and statin versus less statin or placebo for patients not undergoing dialysis. Most significant associations identified in OSs failed to be replicated in RCTs. Associations of high credibility from RCTs were in line with current guidelines. Given the heterogeneity of CKD, it seems hard to assume mortality reductions based on findings from OSs.

Rediscovering Beta-2 Microglobulin As a Biomarker across the Spectrum of Kidney Diseases

There is currently an unmet need for better biomarkers across the spectrum of renal diseases. In this paper, we revisit the role of beta-2 microglobulin (β₂M) as a biomarker in patients with chronic kidney disease and end-stage renal disease. Prior to reviewing the numerous clinical studies in the area, we describe the basic biology of β₂M, focusing in particular on its role in maintaining the serum albumin levels and reclaiming the albumin in tubular fluid through the actions of the neonatal Fc receptor. Disorders of abnormal β₂M function arise as a result of altered binding of β₂M to its protein cofactors and the clinical manifestations are exemplified by rare human genetic conditions and mice knockouts. We highlight the utility of β₂M as a predictor of renal function and clinical outcomes in recent large database studies against predictions made by recently developed whole body population kinetic models. Furthermore, we discuss recent animal data suggesting that contrary to textbook dogma urinary β₂M may be a marker for glomerular rather than tubular pathology. We review the existing literature about β₂M as a biomarker in patients receiving renal replacement therapy, with particular emphasis on large outcome trials. We note emerging proteomic data suggesting that β₂M is a promising marker of chronic allograft nephropathy. Finally, we present data about the role of β₂M as a biomarker in a number of non-renal diseases. The goal of this comprehensive review is to direct attention to the multifaceted role of β₂M as a biomarker, and its exciting biology in order to propose the next steps required to bring this recently rediscovered biomarker into the twenty-first century.