Hemodialysis versus peritoneal dialysis: a comparison of adjusted mortality rates

Comparative analysis of hemodialysis and peritoneal dialysis on the risk of new onset diabetes mellitus

BACKGROUND

Diabetes mellitus is a significant risk factor for cardiovascular events and mortality in dialysis patients. The impact of different dialysis modalities on the risk of new onset diabetes mellitus (NODM) remains a subject of debate. Previous studies did not adequately account for critical confounding factors such as pre-dialysis glycemic status, medication use, and nutritional status, which may influence the association between dialysis modality and NODM risk.

METHODS

We conducted a retrospective cohort study of 1426 non-diabetic end-stage renal disease (ESRD) patients who underwent either hemodialysis (HD) or peritoneal dialysis (PD) at a single medical center. We used different statistical methods, adjusting for potential confounding factors, and accounted for competing risk of death.

RESULTS

Over 12 years, 331 patients (23 %) developed NODM. After adjusting for potential confounding factors and mortality, PD patients had a significantly higher risk of NODM compared to HD patients (adjusted HR 1.52, p = 0.001). A propensity-matched cohort sensitivity analysis yielded similar results. Among patients with prediabetes, those receiving PD had a 2.93 times higher risk of developing NODM than those receiving HD (p for interaction <0.001), whereas no significant difference was observed among euglycemic patients. NODM was also associated with a 1.78 times increased risk of major cardiovascular events.

CONCLUSION

Our study provides evidence that PD treatment may increase the risk of NODM in ESRD patients, particularly among those with preexisting prediabetes. These findings highlight the importance of personalized treatment approaches, and nephrologists should consider prediabetes when choosing the dialysis modality for their patients.

Inpatient peritoneal dialysis catheters placed across the United States during a 3-year period: Lessons learned from 15,000 patients

BACKGROUND

Peritoneal dialysis is a popular option for patients with end-stage renal disease. A recent presidential executive order has incentivized in-home end-stage renal disease treatments, leading to an increase in peritoneal dialysis use. Guidelines exist for creating and maintaining peritoneal dialysis access without addressing the optimal technique. This study evaluates nationwide peritoneal dialysis catheter placement practices and their long-term outcomes.

METHODS

Retrospective cohort analysis of Nationwide Readmission Database from 2017 to 2019. Patients with end-stage renal disease undergoing inpatient peritoneal dialysis catheter placement were included. Six-month readmissions, mortality, and peritoneal dialysis catheter-specific outcome measures were assessed among survivors of admission, including catheter leakage, mechanical breakdown, displacement, revision or replacement, removal, exit site infections, intra-abdominal abscess, and sepsis. Binary logistic regression analyses were performed.

RESULTS

In the study, 14,863 patients with inpatient peritoneal dialysis catheter insertions were identified, of which 7,096 were analyzed (4,150 [59%] laparoscopic, 1,781 [25%] fluoroscopic, 1,165 [16%] open), 847 (12%) had major complications, 931 (13%) were readmitted, and 102 (1.4%) died within 6 months. Univariate analyses demonstrated that laparoscopy had higher mechanical complications, exit-site infections, catheter revision, and removal within 6 months, and fluoroscopy had higher sepsis and mortality. Multivariate analyses showed fluoroscopy was associated with intraabdominal abscess (adjusted odds ratio, 2.36; P = .025), laparoscopy with exit-site infections (adjusted odds ratio, 0.49; P = .005), and open surgery with catheter displacement (adjust odds ratio, 2.95; P = .021).

CONCLUSION

This is the first large-scale study on inpatient peritoneal dialysis catheter placement outcomes in the United States. Fluoroscopic and open surgical placements are routinely performed, but laparoscopy remains the mainstay with fewer exit-site infections. Overall, peritoneal dialysis is a safe option, with 1 in 9 patients having an infectious or mechanical complication within 6 months. Furthermore, large-scale prospective studies are warranted to identify the optimal placement technique.

Mortality of Peritoneal Dialysis versus Hemodialysis in Older Adults: An Updated Systematic Review and Meta-Analysis

INTRODUCTION

The optimal choice of dialysis modality remains contentious in older adults threatened by advanced age and high risk of comorbidities.

METHODS

We conducted a systematic review and meta-analysis of cohort and case-control studies to assess mortality risk between peritoneal dialysis (PD) and hemodialysis (HD) in older adults using PubMed, Embase, and the Cochrane Library database from inception to June 1, 2022. The outcome of interest is all-cause mortality.

RESULTS

Thirty-one eligible studies with >774,000 older patients were included. Pooled analysis showed that PD had a higher mortality rate than HD in older dialysis population (HR 1.17, 95% CI: 1.10-1.25). When stratified by co-variables, our study showed an increased mortality risk of PD versus HD in older patients with diabetes mellitus or comorbidity who underwent longer dialysis duration (more than 3 years) or who started dialysis before 2010. However, definitive conclusions were constrained by significant heterogeneity.

CONCLUSION

From the survival point of view, caution is needed to employ PD for long-term use in older populations with diabetes mellitus or comorbid conditions. However, a tailored treatment choice needs to take account of what matters to older adults at an individual level, especially in the context of limited survival improvements and loss of quality of life. Further research is still awaited to conclude this topic.

Mortality and mode of dialysis: meta-analysis and systematic review

BACKGROUND

The global use of kidney replacement therapy (KRT) has increased, mirroring the incidence of acute kidney injury and chronic kidney disease. Despite its growing clinical usage, patient outcomes with KRT modalities remain controversial. In this meta-analysis, we sought to compare the mortality outcomes of patients with any kidney disease requiring peritoneal dialysis (PD), hemodialysis (HD), or continuous renal replacement therapy (CRRT).

METHODS

The investigation was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). PubMed (MEDLINE), Cochrane Library, and Embase databases were screened for randomized trials and observational studies comparing mortality rates with different KRT modalities in patients with acute or chronic kidney failure. A random-effects model was applied to compute the risk ratio (RR) and 95% confidence intervals (95%CI) with CRRT vs. HD, CRRT vs. PD, and HD vs. PD. Heterogeneity was assessed using I2 statistics, and sensitivity using leave-one-out analysis.

RESULTS

Fifteen eligible studies were identified, allowing comparisons of mortality risk with different dialytic modalities. The relative risk was non-significant in CRRT vs. PD [RR = 0.95, (95%CI 0.53, 1.73), p = 0.92 from 4 studies] and HD vs. CRRT [RR = 1.10, (95%CI 0.95, 1.27), p = 0.21 from five studies] comparisons. The findings remained unchanged in the leave-one-out sensitivity analysis. Although PD was associated with lower mortality risk than HD [RR = 0.78, (95%CI 0.62, 0.97), p = 0.03], the significance was lost with the exclusion of 4 out of 5 included studies.

CONCLUSION

The current evidence indicates that while patients receiving CRRT may have similar mortality risks compared to those receiving HD or PD, PD may be associated with lower mortality risk compared to HD. However, high heterogeneity among the included studies limits the generalizability of our findings. High-quality studies comparing mortality outcomes with different dialytic modalities in CKD are necessary for a more robust safety and efficacy evaluation.

Impact of Pretransplant Dialysis Modality on Posttransplant Outcomes: A Single-Center Experience

OBJECTIVES

It remains unclear whether posttransplant outcomes differ according to the pretransplant dialysis modality (peritoneal dialysis vs hemodialysis). Our aim was to assess posttransplant outcomes in patients with different predialysis modalities.

MATERIALS AND METHODS

Two thousand two hundred fifty-eight kidney recipients following up in Hamed Alessa Organ transplant center in Kuwait were included and divided into two groups according to pre-transplant dialysis modality: Group 1: those who received hemodialysis (HD) and group 2: those with peritoneal dialysis (PD). Demographics, pretransplant and posttransplant comorbidities, and patient and graft outcomes were studied.

RESULTS

There were 1956 patients on hemodialysis, and 302 patients were on peritoneal dialysis. Most were male patients (1456 vs 802 female patients), with comparable mean age (P = .34). Chronic glomerulonephritis and diabetic nephropathy represented the most common original kidney disease before transplant (27.6% and 21.4%, respectively), with higher prevalence of glomerulonephritis in group 1 and diabetic nephropathy in group 2 (P = .001). The 2 groups were comparable with regard to immunosuppression (induction and maintenance) (P > .05). Posttransplant diabetes and hypertension were significantly higher in the hemodialysis group (P = .004 and P = 003, respectively). There was no significant difference between the 2 groups with regard to the graft outcome (P = .86). However, patient survival was significantly higher in the hemodialysis group (81.2% vs 64.4%).

CONCLUSIONS

Compared with peritoneal dialysis, pretransplant hemodialysis is associated with better posttransplant patient survival despite no difference in the graft outcome. Diabetes-related complications could be attributed to such outcomes.

SAGES peritoneal dialysis access guideline update 2023

BACKGROUND

Minimally invasive surgery has been used for both de novo insertion and salvage of peritoneal dialysis (PD) catheters. Advanced laparoscopic, basic laparoscopic, open, and image-guided techniques have evolved as the most popular techniques. The aim of this guideline was to develop evidence-based guidelines that support surgeons, patients, and other physicians in decisions on minimally invasive peritoneal dialysis access and the salvage of malfunctioning catheters in both adults and children.

METHODS

A guidelines committee panel of the Society of American Gastrointestinal and Endoscopic Surgeons reviewed the literature since the prior guideline was published in 2014 and developed seven key questions in adults and four in children. After a systematic review of the literature, by the panel, evidence-based recommendations were formulated using the Grading of Recommendations Assessment, Development and Evaluation approach. Recommendations for future research were also proposed.

RESULTS

After systematic review, data extraction, and evidence to decision meetings, the panel agreed on twelve recommendations for the peri-operative performance of laparoscopic peritoneal dialysis access surgery and management of catheter dysfunction.

CONCLUSIONS

In the adult population, conditional recommendations were made in favor of: staged hernia repair followed by PD catheter insertion over simultaneous and traditional start over urgent start of PD when medically possible. Furthermore, the panel suggested advanced laparoscopic insertion techniques rather than basic laparoscopic techniques or open insertion. Conditional recommendations were made for either advanced laparoscopic or image-guided percutaneous insertion and for either nonoperative or operative salvage. A recommendation could not be made regarding concomitant clean-contaminated surgery in adults. In the pediatric population, conditional recommendations were made for either traditional or urgent start of PD, concomitant clean or clean-contaminated surgery and PD catheter placement rather than staged, and advanced laparoscopic placement rather than basic or open insertion.

Peritoneal Dialysis Catheter Complications after Insertion by Surgeons, Radiologists, or Nephrologists

SIGNIFICANCE STATEMENT

The Advancing American Kidney Health Initiative aims to increase rates of utilization of peritoneal dialysis (PD) in the United States. One of the first steps to PD is successful catheter placement, which can be performed by surgeons, interventional radiologists, or nephrologists. We examined the association between operator subspecialty and risk of needing a follow-up procedure in the first 90 days after initial PD catheter implantation. Overall, we found that 15.5% of catheters required revision, removal, or a second catheter placement within 90 days. The odds of requiring a follow-up procedure was 36% higher for interventional radiologists and 86% higher for interventional nephrologists compared with general surgeons. Further research is needed to understand how to optimize the function of catheters across different operator types.

BACKGROUND

The US government has implemented incentives to increase the use of PD. Successful placement of PD catheters is an important step to increasing PD utilization rates. Our objective was to compare initial outcomes after PD catheter placement by different types of operators.

METHODS

We included PD-naïve patients insured by Medicare who had a PD catheter inserted between 2010 and 2019. We examined the association between specialty of the operator (general surgeon, vascular surgeon, interventional radiologist, or interventional nephrologist) and odds of needing a follow-up procedure, which we defined as catheter removal, replacement, or revision within 90 days of the initial procedure. Mixed logistic regression models clustered by operator were used to examine the association between operator type and outcomes.

RESULTS

We included 46,973 patients treated by 5205 operators (71.1% general surgeons, 17.2% vascular surgeons, 9.7% interventional radiologists, 2.0% interventional nephrologists). 15.5% of patients required a follow-up procedure within 90 days of the initial insertion, of whom 2.9% had a second PD catheter implanted, 6.6% underwent PD catheter removal, and 5.9% had a PD catheter revision within 90 days of the initial insertion. In models adjusted for patient and operator characteristics, the odds of requiring a follow-up procedure within 90 days were highest for interventional nephrologists (HR, 1.86; 95% confidence interval [CI], 1.56 to 2.22) and interventional radiologists (odds ratio, 1.36; 95% CI, 1.17 to 1.58) followed by vascular surgeons (odds ratio, 1.06; 95% CI, 0.97 to 1.14) compared with general surgeons.

CONCLUSIONS

The probability of needing a follow-up procedure after initial PD catheter placement varied by operator specialty and was higher for interventionalists and lowest for general surgeons.

Home Dialysis in North America: The Current State

There is widespread interest in expanding the uptake of home dialysis in North America. Although kidney transplantation should be the preferred option in eligible patients, home hemodialysis (HD) and peritoneal dialysis (PD) offer cost-effective options for KRT. In this review, the motivation for promoting home dialysis is presented, and the literature supporting it is critically reviewed. Randomized comparisons of home HD and PD with in-center HD have been challenging to conduct and provide only limited information. Nonrandomized studies are heterogeneous in their design and have often yielded conflicting results. They are prone to bias, and this must be carefully considered when evaluating this literature. Home modalities seem to have equivalent clinical outcomes and quality of life when compared with in-center HD. However, the cost of providing home therapies, particularly PD, is lower than conventional, in-center HD. Measures of home dialysis utilization, the philosophy behind their measurement, and important factors to consider when interpreting them are discussed. The importance of understanding measures of home dialysis utilization in the context of rates of kidney failure, the proportion of individuals who opt for conservative care, and rates of kidney transplantation is highlighted, and a framework for proposing targets is presented, using PD as an example.

Metabolomics profiling distinctively identified end-stage renal disease patients from chronic kidney disease patients

Chronic kidney disease (CKD) is a serious public health problem characterized by progressive kidney function loss leading to end-stage renal disease (ESRD) that demands dialysis or kidney transplantation. Early detection can prevent or delay progression to ESRD. The study aimed to gain new insights into the perturbed biochemical reactions and to identify novel distinct biomarkers between ESRD and CKD. Serum samples of 32 patients with ESRD (n = 13) and CKD (n = 19) were analyzed using chemical isotope labeling liquid chromatography-mass spectrometry metabolomics approach. A total of 193 metabolites were significantly altered in ESRD compared to CKD and were mainly involved in aminoacyl-tRNA biosynthesis, branched-chain amino acid (BCAA) biosynthesis, taurine metabolism, and tryptophan metabolism. Three kynurenine derivatives, namely, 2-aminobenzoic acid, xanthurenic acid, and hydroxypicolinic acid were upregulated in ESRD compared to CKD due to the significant decrease in glomerular filtration rate with the progression of CKD to ESRD. N-Hydroxy-isoleucine, 2-aminobenzoic acid, and picolinic acid yielded AUC > 0.99 when analyzed using Receiver Operating Characteristic (ROC) analysis. Our findings suggest that inhibiting the kynurenine pathway might be a promising target to delay CKD progression and that metabolites with high discriminative ability might serve as potential prognostic biomarkers to monitor the progression of CKD to ESRD or used in combination with current markers to indicate the status of kidney damage better.

Financial Incentives to Facilities and Clinicians Treating Patients With End-stage Kidney Disease and Use of Home Dialysis: A Randomized Clinical Trial

Importance

Home dialysis rates for end-stage kidney disease (ESKD) treatment are substantially lower in the US than in other high-income countries, yet there is limited knowledge on how to increase these rates.

Objective

To report results from the first year of a nationwide randomized clinical trial that provides financial incentives to ESKD facilities and managing clinicians to increase home dialysis rates.

Design, Setting, and Participants

Results were analyzed from the first year of the End-Stage Renal Disease Treatment Choice (ETC) model, a multiyear, mandatory-participation randomized clinical trial designed and implemented by the US Center for Medicare & Medicaid Innovation. Data were reported on Medicare patients with ESKD 66 years or older who initiated treatment with dialysis in 2021, with data collection through December 31, 2021; the study included all eligible ESKD facilities and managing clinicians. Eligible hospital referral regions (HRRs) were randomly assigned to the ETC (91 HRRs) or a control group (211 HRRs).

Interventions

The ESKD facilities and managing clinicians received financial incentives for home dialysis use.

Main Outcomes and Measures

The primary outcome was the percentage of patients with ESKD who received any home dialysis during the first 90 days of treatment. Secondary outcomes included other measures of home dialysis and patient volume and characteristics.

Results

Among the 302 HRRs eligible for randomization, 18 621 eligible patients initiated dialysis treatment during the study period (mean [SD] age, 74.8 [1.05] years; 7856 women [42.1%]; 10 765 men [57.9%]; 859 Asian [5.2%], 3280 [17.7%] Black, 730 [4.3%] Hispanic, 239 North American Native, and 12 394 managing clinicians. The mean (SD) share of patients with any home dialysis during the first 90 days was 20.6% (7.8%) in the control group and was 0.12 percentage points higher (95% CI, -1.42 to 1.65 percentage points; P = .88) in the ETC group, a statistically nonsignificant difference. None of the secondary outcomes differed significantly between groups.

Conclusions and Relevance

The trial results found that in the first year of the US Center for Medicare & Medicaid Innovation-designed ETC model, HRRs assigned to the model did not have statistically significantly different rates in home dialysis compared with control HRRs. This raises questions about the efficacy of the financial incentives provided, although further evaluation is needed, as the size of these incentives will increase in subsequent years.

Trial Registration

ClinicalTrials.gov Identifier: NCT05005572.

Multifaceted Intervention to Increase the Use of Home Dialysis: A Cluster Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Home dialysis therapies (peritoneal and home hemodialysis) are less expensive and provide similar outcomes to in-center hemodialysis, but they are underutilized in most health systems. Given this, we designed a multifaceted intervention to increase the use of home dialysis. In this study, our objective was to evaluate the effect of this intervention on home dialysis use in CKD clinics across Canada.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a cluster randomized controlled trial in 55 CKD clinic clusters in nine provinces in Canada between October 2014 and November 2015. Participants included all adult patients who initiated dialysis in the year following the intervention. We evaluated the implementation of a four-component intervention, which included phone surveys from a knowledge translation broker, a 1-year center-specific audit/feedback on home dialysis use, delivery of an educational package (including tools aimed at both providers and patients), and an academic detailing visit. The primary outcome was the proportion of patients using home dialysis at 180 days after dialysis initiation.

RESULTS

A total of 55 clinics were randomized (27 in the intervention and 28 in the control), with 5312 patients initiating dialysis in the 1-year follow-up period. In the primary analysis, there was no difference in the use of home dialysis at 180 days in the intervention and control clusters (absolute risk difference, 4%; 95% confidence interval, -2% to 10%). Using a difference-in-difference comparison, the use of home dialysis at 180 days was similar before and after implementation of the intervention (difference of 0% in intervention clinics; 95% confidence interval, -2% to 3%; difference of 0.8% in control clinics; 95% confidence interval, -1% to 3%; P=0.84).

CONCLUSIONS

A multifaceted intervention did not increase the use of home dialysis in adults initiating dialysis.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

A Cluster Randomized Trial to Assess the Impact of Patient and Provider Education on Use of Home Dialysis, NCT02202018.

Epidemiology of haemodialysis outcomes

Haemodialysis (HD) is the commonest form of kidney replacement therapy in the world, accounting for approximately 69% of all kidney replacement therapy and 89% of all dialysis. Over the last six decades since the inception of HD, dialysis technology and patient access to the therapy have advanced considerably, particularly in high-income countries. However, HD availability, accessibility, cost and outcomes vary widely across the world and, overall, the rates of impaired quality of life, morbidity and mortality are high. Cardiovascular disease affects more than two-thirds of people receiving HD, is the major cause of morbidity and accounts for almost 50% of mortality. In addition, patients on HD have high symptom loads and are often under considerable financial strain. Despite the many advances in HD technology and delivery systems that have been achieved since the treatment was first developed, poor outcomes among patients receiving HD remain a major public health concern. Understanding the epidemiology of HD outcomes, why they might vary across different populations and how they might be improved is therefore crucial, although this goal is hampered by the considerable heterogeneity in the monitoring and reporting of these outcomes across settings.

This Review examines the epidemiology of haemodialysis outcomes — clinical, patient-reported and surrogate outcomes — across world regions and populations, including vulnerable individuals. The authors also discuss the current status of monitoring and reporting of haemodialysis outcomes and potential strategies for improvement.

Nearly 4 million people in the world are living on kidney replacement therapy (KRT), and haemodialysis (HD) remains the commonest form of KRT, accounting for approximately 69% of all KRT and 89% of all dialysis.

Dialysis technology and patient access to KRT have advanced substantially since the 1960s, particularly in high-income countries. However, HD availability, accessibility, cost and outcomes continue to vary widely across countries, particularly among disadvantaged populations (including Indigenous peoples, women and people at the extremes of age).

Cardiovascular disease affects over two-thirds of people receiving HD, is the major cause of morbidity and accounts for almost 50% of mortality; mortality among patients on HD is significantly higher than that of their counterparts in the general population, and treated kidney failure has a higher mortality than many types of cancer. Patients on HD also experience high burdens of symptoms, poor quality of life and financial difficulties.

Careful monitoring of the outcomes of patients on HD is essential to develop effective strategies for risk reduction. Outcome measures are highly variable across regions, countries, centres and segments of the population. Establishing kidney registries that collect a variety of clinical and patient-reported outcomes using harmonized definitions is therefore crucial.

Evaluation of HD outcomes should include the impact on family and friends, and personal finances, and should examine inequities in disadvantaged populations, who comprise a large proportion of the HD population.

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient’s needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Implantation of a peritoneal dialysis catheter in patients with ESRD using local anesthesia and Remifentanil

Study objective

The main objective of this study is to test the feasibility of the local anesthetic (LA) Mepivacaine 1% and sedation with Remifentanil as the primary anesthetic technique for the insertion of a peritoneal dialysis (PD) catheter, without the need to convert to general anesthesia.

Methods

We analyzed 27 consecutive end-stage renal disease (ESRD) patients who underwent the placement of a peritoneal catheter at our center between March 2015 and January 2019. The procedures were all performed by a general or vascular surgeon, and the postoperative care and follow-up were all conducted by the same peritoneal dialysis team.

Results

All of the 27 subjects successfully underwent the procedure without the need of conversion to general anesthesia. The catheter was deemed prone to usage in all patients and was found to be leak-proof in 100% of the patients.

Conclusion

This study describes a safe and successful approach for insertion of a PD catheter by combined infiltration of the local anesthetic Mepivacaine 1% and sedation with Remifentanil. Hereby, ESRD patients can be treated without general anesthesia, while ensuring functionality of the PD catheter.

Survival analysis in the incident dialysis patients by different modalities

BACKGROUND

To analysis survival in onset uremic patients who initiating HD or PD dialysis in our dialysis center.

METHODS

Between Jan. 2015 and June. 2018, patients with onset uremia and initiating planned-start dialysis were retrospectively enrolled in this study and followed up to January, 2019. The relationships between the types of dialysis modality and patient prognosis were assessed.

RESULTS

A total of 460 patients were included in the final analysis. Of which, 213 patient (46.30%) undergoing PD and 247 patients (53.70%) undergoing HD with arteriovenous fistula. The average follow-up time was 27.9 months. Eighty-seven (18.91%) patients died during the study period. The all-cause mortality was 127 per 1000 person-year. It was 102 per 1000 person-year in the HD group and 171 per 1000 person-year in the PD group (p < 0.01). However, dialysis modality was not an independent predictor for survival. During the first year after dialysis initiation, patient survival was comparable between the PD and HD groups (log-rank p = 0.14). As the dialysis age increased over 1 year, HD patients seemed to have a better survival as compared to that of PD patient (log-rank p < 0.05), especially those older than 65 years and without DN.

CONCLUSIONS

Though dialysis modality was not an independent factor for overall survival, HD therapy seemed to be more suitable for patients without DN.

Retrospective studies - utility and caveats

A thorough understanding of the pros and cons of the various study designs is critical to correct interpretation of their results. Retrospective studies are an important tool to study rare diseases, manifestations and outcomes. Findings of these studies can form the basis on which prospective studies are planned. Retrospective studies however have several limitations owing to their design. Since they depend on review of charts that were originally not designed to collect data for research, some information is bound to be missing. Selection and recall biases also affect the results and reasons for differences in treatment between patients and lost follow ups can often not be ascertained and may lead to bias. Readers need to critically evaluate the methods and carefully interpret the results of retrospective studies before they put them to practice. Researchers should avoid over generalisation of results and be cautious in claiming cause-effect relationship in retrospective studies.

Evidence-Based Decision Making 7: Health Economics in Clinical Research

The pressure for health-care systems to provide more resource-intensive health care and newer more costly therapies is significant, despite limited health-care budgets. As such, demonstration that a new therapy is effective is no longer sufficient to ensure that it is funded within publicly funded health-care systems. The impact of a therapy on health-care costs is also an important consideration for decision makers who must allocate scarce resources. The clinical benefits and costs of a new therapy can be estimated simultaneously using economic evaluation; the strengths and limitations of which are discussed herein. In addition, within this chapter, we discuss the important economic outcomes that can be collected within a clinical trial (alongside the clinical outcome data) enabling consideration of the impact of the therapy on overall resource use, thus enabling performance of an economic evaluation, if the therapy is shown to be effective.

Red blood cell distribution width predicts residual renal function decline in patients undergoing continuous ambulatory peritoneal dialysis

To investigate the relationship between red blood cell distribution width (RDW) and residual renal function (RRF) in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Seventy-seven CAPD patients were enrolled in this study. According to receiver operator characteristic (ROC) curve analysis, patients were divided into high RDW (RDW > 14.95%) and low RDW (RDW ≤ 14.95%) groups. The data of baseline clinical, biochemical parameters, comorbidities, medication status, peritoneal function, and dialysis adequacy were compared. Survival curves were calculated using Kaplan-Meier method. Cox regression model was employed to analyze risk factors of decline in RRF. The overall median survival time was 24 months, the median survival time of high RDW group (46 patients) and low RDW group (31 patients) were 24 and 12 months, respectively. Compared with the low RDW group, patients in the high RDW group were older, higher rate of decline RRF and white blood cells count as well as lower total Kt/V (all p < 0.05). Kaplan-Meier survival curves showed that the low RDW group had higher survival of RRF compared with the high RDW group (p < 0.001). Multivariate Cox regression analysis showed that high RDW was independent risk factor for decline of RRF(hazard ratio = 1.441, 95% confidence interval: 1.089-1.905, p = 0.01). Increased baseline RDW is associated with decline of RRF in CAPD patients and RDW can be stratified as a valuable indicator for the risk of RRF decline.

CENTRAL NERVOUS SYSTEM RESPONSE TO CHRONIC KIDNEY DISEASE

Due to the aging of the human population, the prevalence of chronic diseases such as chronic kidney disease (CKD) is increasing every year. Chronic kidney disease is a general term that refers to heterogeneous disorders that affect kidney structure and function. Decrease in glomerular filtration can be defined as chronic and progressive deterioration in fluid-solute balance, metabolic and endocrine functions of the kidney. CKD often affects the elderly. With the advancement of age, some structural and functional changes occur in the kidneys. Therefore, the number of patients suffering from mild and moderate CKD is expected to increase in the future.CKD leads to the deep metabolic and hemodynamic changes that damage other organs, such as the heart and brain. CNS abnormalities and cognitive deficits progress with the severity of CBS and occurs mostly among hemodialysis patients. It also has great socio-economic effects on individuals. Since symptoms of CKD are not often found in patients, early recognition of risk factors is the main point. For this reason, it is necessary to identify possible protective and preventive treatments to be applied in at-risk groups and to examine these mechanisms for the treatment of the disease. This review provides available information on the relevant mechanisms.

Weighted estimators of the complier average causal effect on restricted mean survival time with observed instrument-outcome confounders

A major concern in any observational study is unmeasured confounding of the relationship between a treatment and outcome of interest. Instrumental variable (IV) analysis methods are able to control for unmeasured confounding. However, IV analysis methods developed for censored time-to-event data tend to rely on assumptions that may not be reasonable in many practical applications, making them unsuitable for use in observational studies. In this report, we develop weighted estimators of the complier average causal effect (CACE) on the restricted mean survival time in the overall population as well as in an evenly matchable population (CACE-m). Our method is able to accommodate instrument-outcome confounding and adjust for covariate-dependent censoring, making it particularly suited for causal inference from observational studies. We establish the asymptotic properties and derive easily implementable asymptotic variance estimators for the proposed estimators. Through simulation studies, we show that the proposed estimators tend to be more efficient than instrument propensity score matching-based estimators or IPIW estimators. We apply our method to compare dialytic modality-specific survival for end stage renal disease patients using data from the U.S. Renal Data System.

Influence of peritoneal dialysis catheter type on complications and long-term outcomes: an updated systematic review and meta-analysis

BACKGROUND

There is currently no consensus regarding the optimal type of peritoneal dialysis catheter (PDC). We compared the outcomes of PDCs according to the number of cuffs, intercuff and intraperitoneal segment shape, and presence of a weighted tip.

METHODS

A systematic review of the literature was performed using the MEDLINE and Cochrane Library databases (end-of-search date: October 16th, 2019). We included studies comparing double-cuff vs. single-cuff, swan-neck vs. straight-neck, coiled-tip vs. straight-tip, and weighted vs. non-weighted PDCs for the outcomes of interest. We performed meta-analyses using the random-effects model. We assessed the risk of bias using the Newcastle-Ottawa scale and the Cochrane Collaboration's Tool.

RESULTS

In total, 38 studies were identified, of which 20 were randomized controlled trials (RCTs) and 18 were observational studies. No statistically significant differences were detected between double-cuff vs. single-cuff, swan-neck vs. straight-neck, and coiled-tip vs. straight tip PDCs in any of the outcomes of interest. Weighted catheters were associated with significantly lower rates of tunnel infection (relative risk [RR] 0.52, 95% confidence interval [CI] 0.31-0.95, p = 0.03), migration (RR 0.07, 95% CI 0.03-0.16, p < 0.001), drainage failure (RR 0.62, 95% CI 0.39-0.96, p = 0.03), cuff extrusion (RR 0.40, 95% CI 0.21-0.74, p < 0.001), and complication-related removal (RR 0.53, 95% CI 0.44-0.64, p < 0.001).

DISCUSSION

Among the different types of PDCs, weighted catheters result in lower complication rates and superior long-term outcomes compared to non-weighted catheters. Other aspects of the catheter design do not significantly affect PDC outcomes.

PROTOCOL REGISTRATION

PROSPERO 2020 CRD42020158177.

Metabolomics Evaluation of Patients With Stage 5 Chronic Kidney Disease Before Dialysis, Maintenance Hemodialysis, and Peritoneal Dialysis

Objective

Current treatment options for patients with stage 5 chronic kidney disease before dialysis (predialysis CKD-5) are determined by individual circumstances, economic factors, and the doctor’s advice. This study aimed to explore the plasma metabolic traits of patients with predialysis CKD-5 compared with maintenance hemodialysis (HD) and peritoneal dialysis (PD) patients, to learn more about the impact of the dialysis process on the blood environment.

Methods

Our study enrolled 31 predialysis CKD-5 patients, 31 HD patients, and 30 PD patients. Metabolite profiling was performed using a targeted metabolomics platform by applying an ultra-high-performance liquid chromatography-tandem mass spectrometry method, and the subsequent comparisons among all three groups were made to explore metabolic alterations.

Results

Cysteine metabolism was significantly altered between predialysis CKD-5 patients and both groups of dialysis patients. A disturbance in purine metabolism was the most extensively changed pathway identified between the HD and PD groups. A total of 20 discriminating metabolites with large fluctuations in plasma concentrations were screened from the group comparisons, including 2-keto-D-gluconic acid, kynurenic acid, s-adenosylhomocysteine, L-glutamine, adenosine, and nicotinamide.

Conclusion

Our study provided a comprehensive metabolomics evaluation among predialysis CKD-5, HD, and PD patients, which described the disturbance of metabolic pathways, discriminating metabolites and their possible biological significances. The identification of specific metabolites related to dialysis therapy might provide insights for the management of advanced CKD stages and inform shared decision-making.

Aberrant serum parathyroid hormone, calcium, and phosphorus as risk factors for peritonitis in peritoneal dialysis patients

Identifying modifiable risk factors of peritoneal dialysis (PD)-related peritonitis is of clinical importance in patient care. Mineral bone disease (MBD) has been associated with mortality and morbidity in end-stage kidney disease (ESKD) patients. However, its influence on PD related peritonitis due to altered host immunity remains elusive. This study investigated whether abnormal biomarkers of MBD are associated with the development of peritonitis in patients undergoing maintenance PD. We conducted a retrospective observational cohort study, analysing data derived from a nationwide dialysis registry database in Taiwan, from 2005 to 2012. A total of 5750 ESKD patients commencing PD therapy during this period were enrolled and followed up to 60 months or by the end of the study period. The patients were stratified based on their baseline serum parathyroid hormone (PTH) levels, calcium (Ca) levels or phosphorus (P) levels, respectively or in combinations. The primary outcome was the occurrence of first episode of peritonitis, and patient outcomes such as deaths, transfer to haemodialysis or receiving renal transplantation were censored. Peritonitis-free survival and the influence of PTH, Ca, P (individual or in combination) on the peritonitis occurrence were analysed. A total of 5750 PD patients was enrolled. Of them, 1611 patients experienced their first episode of peritonitis during the study period. Patients with low PTH, high Ca or low P levels, respectively or in combination, had the lowest peritonitis-free survival. After adjusting for age, sex and serum albumin levels, we found that the combinations of low PTH levels with either high Ca levels or low/normal P levels were significant risk factors of developing peritonitis. Abnormal mineral bone metabolism in maintenance PD patients with low serum PTH levels, in combination with either high Ca levels or low/normal P levels, could be novel risk factors of PD-related peritonitis.

30 Years of Peritoneal Dialysis Development: The past and the Future

A review is given of 30 years of development in peritoneal dialysis (PD). After a short description of the first 20 years, the main emphasis is put on the last 10 years. Subjects discussed are the increasing use of PD in high-risk populations, peritonitis and other catheter-related problems, adequacy of dialysis and nutrition, patient outcomes in comparison with hemodialysis, and peritoneal membrane changes with time on PD. Topics that have emerged during the last decade and the challenges for the next decennium are discussed. The great importance of quality assurance in fast-growing PD populations and of prevention of long-term membrane alterations are emphasized.

Peritoneal Dialysis Utilization and Outcome: What are we Facing?

Penetration of peritoneal dialysis (PD) varies tremendously across the world. It ranges from about 80% in Hong Kong and Mexico to just a few percentage points in the United States, Japan, and Germany. While PD is growing in China, India, and some Eastern European and South American countries, it is declining in many European and North American countries. In terms of outcomes, the survival of PD patients is generally comparable to that of hemodialysis (HD) patients and better than that of HD patients during the first few years on dialysis. According to the U.S. Renal Data System, survival of patients on PD has been improving faster than that of patients on HD. In terms of cost, PD is usually cheaper than HD. Hence, declining PD utilization is unjustified. Work is required to identify and overcome negative factors such as physician bias, unfair medical reimbursement systems, and poor patient education.

Peritoneal Dialysis in Patients with Diabetes: Are the Benefits Greater than the Disadvantages?

Diabetic nephropathy has been increasing in prevalence in recent years, and it is now the dominant cause of end-stage renal disease (ESRD) worldwide. Because diabetes is frequently associated with multiple complications, nephrologists must be alert to the selection of dialysis modality so as to reduce the accompanying risks. The present review addresses whether the benefits of peritoneal dialysis are greater than its disadvantages in diabetic patients. The answer is quite positive: for most diabetic patients, peritoneal dialysis offers multiple benefits.

Survival Among Incident Peritoneal Dialysis Versus Hemodialysis Patients Who Initiate With an Arteriovenous Fistula

Rationale & Objective

Comparisons of outcomes between in-center hemodialysis (HD) and peritoneal dialysis (PD) are confounded by selection bias because PD patients are typically younger and healthier and may have received longer predialysis care. We compared first-year survival between what we hypothesized were clinically equivalent groups; namely, patients who initiate maintenance HD using an arteriovenous fistula (AVF) and those selecting PD as their initial modality.

Study Design

Observational, registry-based, retrospective cohort study.

Setting & Participants

US Renal Data System data for 5 annual cohorts (2010-2014; n = 130,324) of incident HD with an AVF and incident PD patients.

Exposures and Predictors

Exposure was more than 1 day receiving PD or more than 1 day receiving HD with an AVF. Time at risk for both cohorts was determined for 12 consecutive 30-day segments, censoring for transplantation, loss to follow-up, or end of time. Predictors included patient-level characteristics obtained from Centers for Medicare & Medicaid Services 2728 Form and other data sources.

Outcomes

Patient survival.

Analytical Approach

Unadjusted and multivariable risk-adjusted HRs for death of HD versus PD patients, averaged over 2010 to 2014, were calculated.

Results

The HD cohort's average unadjusted mortality rate was consistently higher than for the PD cohort. The HR of HD versus PD was 1.25 (95% CI, 1.20-1.30) in the unadjusted model and 0.84 (95% CI, 0.80-0.87) in the adjusted model. However, multivariable risk-adjusted analyses showed the HR of HD versus PD for the first 90 days was 1.06 (95% CI, 0.98-1.14), decreasing to 0.74 (95% CI, 0.68-0.80) in the 270- to 360-day period.

Limitations

Residual confounding due to selection bias inherent in dialysis modality choice and the observational study design. Form 2728 provides baseline data at dialysis incidence alone, but not over time.

Conclusions

US patients receiving HD with an AVF appear to have a survival advantage over PD patients after 90 days of dialysis initiation after accounting for patient characteristics. These findings have implications in the choice of initial dialysis modality and vascular access for patients.

Differences of connectivity between ESRD patients with PD and HD

OBJECTIVES

The aim of this study was to investigate alterations in structural and functional brain connectivity between patients with end-stage renal disease (ESRD) who were undergoing peritoneal dialysis (PD) and hemodialysis (HD).

METHODS

We enrolled 40 patients with ESRD who were undergoing PD (20 patients) and HD (20 patients). We also enrolled healthy participants as a control group. All of the subjects underwent diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI). Using data from the structural and functional connectivity matrix based on DTI and rs-fMRI, we calculated several network measures using graph theoretical analysis.

RESULTS

The measures of global structural connectivity were significantly different between the patients with ESRD who were undergoing PD and healthy subjects. The global efficiency and local efficiency in the patients with PD were significantly decreased compared with those in healthy participants. However, all of the measures of global structural connectivity in the patients with HD were not different from those in healthy participants. Conversely, in the global functional connectivity, the characteristic path length was significantly increased and the small-worldness index was decreased in patients with HD. However, the measures of the global functional connectivity in the patients with PD were not different from those in healthy subjects.

CONCLUSION

This study revealed that alterations in structural and functional connectivity in patients who were undergoing PD and HD were different than those in healthy controls. These findings suggest that brain networks may be affected by different types of renal replacement therapy.

The current and future landscape of dialysis

The development of dialysis by early pioneers such as Willem Kolff and Belding Scribner set in motion several dramatic changes in the epidemiology, economics and ethical frameworks for the treatment of kidney failure. However, despite a rapid expansion in the provision of dialysis — particularly haemodialysis and most notably in high-income countries (HICs) — the rate of true patient-centred innovation has slowed. Current trends are particularly concerning from a global perspective: current costs are not sustainable, even for HICs, and globally, most people who develop kidney failure forego treatment, resulting in millions of deaths every year. Thus, there is an urgent need to develop new approaches and dialysis modalities that are cost-effective, accessible and offer improved patient outcomes. Nephrology researchers are increasingly engaging with patients to determine their priorities for meaningful outcomes that should be used to measure progress. The overarching message from this engagement is that while patients value longevity, reducing symptom burden and achieving maximal functional and social rehabilitation are prioritized more highly. In response, patients, payors, regulators and health-care systems are increasingly demanding improved value, which can only come about through true patient-centred innovation that supports high-quality, high-value care. Substantial efforts are now underway to support requisite transformative changes. These efforts need to be catalysed, promoted and fostered through international collaboration and harmonization.

Dialysis is a life-saving therapy; however, costs of dialysis are high, access is inequitable and outcomes are inadequate. This Review describes the current landscape of dialysis therapy from an epidemiological, economic, ethical and patient-centred framework, and describes initiatives that are aimed at stimulating innovations in the field to one that supports high-quality, high-value care.

The global dialysis population is growing rapidly, especially in low-income and middle-income countries; however, worldwide, a substantial number of people lack access to kidney replacement therapy, and millions of people die of kidney failure each year, often without supportive care.

The costs of dialysis care are high and will likely continue to rise as a result of increased life expectancy and improved therapies for causes of kidney failure such as diabetes mellitus and cardiovascular disease.

Patients on dialysis continue to bear a high burden of disease, shortened life expectancy and report a high symptom burden and a low health-related quality of life.

Patient-focused research has identified fatigue, insomnia, cramps, depression, anxiety and frustration as key symptoms contributing to unsatisfactory outcomes for patients on dialysis.

Initiatives to transform dialysis outcomes for patients require both top-down efforts (that is, efforts that promote incentives based on systems level policy, regulations, macroeconomic and organizational changes) and bottom-up efforts (that is, patient-led and patient-centred advocacy efforts as well as efforts led by individual teams of innovators).

Patients, payors, regulators and health-care systems increasingly demand improved value in dialysis care, which can only come about through true patient-centred innovation that supports high-quality, high-value care.

Comparative Study on the Outcomes of Elective-Start versus Urgent-Start Peritoneal Dialysis Catheter Placement

The aim of this study is to compare the outcomes of the elective-start versus urgent-start use of peritoneal dialysis (PD) catheters using percutaneous radiologic or laparoscopic techniques. Patients having their first peritoneal dialysis catheter placed and used between January 2005 and January 2018 were identified, and their medical records were retrospectively reviewed. Two groups were identified: elective-start (n = 211) and urgent-start (n = 29). Patient's demographics were similar between the two groups with the exception of age, which was higher in the elective-start group. The catheter complication rates and catheter removal rates at 3 and 12 months, mean days-to-first complication, mean days-to-catheter removal, and overall patient survival at 12 months were analyzed. Catheter complication rates at 3 and 12 months were similar between the two groups (27.8% and 48.9%, respectively, in the elective-start group versus 35.9% and 54.2%, respectively, in the urgent-start group, p=0.415). The catheter removal rates at 3 and 12 months were also similar between the two groups (p=0.088). Catheter leak was higher in the urgent-start group (13.8% versus 3.3%, respectively, p=0.011). There was no difference between the elective-start and the urgent-start groups in the mean days-to-first complication (95 vs 69, p=0.086), mean days-to-catheter removal (145 vs 127, p=0.757), and overall patient survival at 12 months (100% vs 97%, p=0.41). In conclusion, apart from catheter leak, there were similar rates of catheter complication and removal for PD catheter used for the elective-start compared to the urgent-start PD. Furthermore, the technique of placement did not affect the outcomes.

eHealth interventions to support patients in delivering and managing peritoneal dialysis at home: A systematic review

Peritoneal dialysis (PD) requires patients to develop a variety of self-management skills in order to effectively deliver and manage their dialysis at home. eHealth interventions may provide patients with accessible information to develop the skills and knowledge they require to manage their treatment. This review aims to identify and evaluate 'active' eHealth interventions in supporting patients on PD. Six databases were included within the review using the terms Peritoneal Dialysis, eHealth, telemedicine and remote consultation. Studies which explored patients who were delivering PD, an intervention where the main component involved a digital device and required active engagement from patients were included. The primary outcomes examined were identified using the core outcomes recommended by the Standardised Outcomes in Nephrology in Peritoneal Dialysis initiative (PD infection, cardiovascular disease, mortality, PD failure and life participation). Hospitalisation rates were also considered as a primary outcome. Secondary outcomes included quality of life, patient skills, patient knowledge and satisfaction. Using the inclusion criteria, 15 studies (1334 participants) were included in the study. The effectiveness of eHealth interventions was mixed. Due to high heterogeneity, a meta-analysis was not possible, and quality of evidence was low. Risk of bias across the randomised studies was unclear but bias across non-randomised studies was identified as critical. There were no reported adverse effects of eHealth interventions within the included studies. Despite the high interest of eHealth interventions in PD, good quality evidence is needed to explore their effectiveness before a wider application of eHealth interventions.

Complications and outcomes of urgent-start peritoneal dialysis in elderly patients with end-stage renal disease in China: a retrospective cohort study

OBJECTIVES

To investigate the complications and survival of elderly patients with end-stage renal disease (ESRD) who received urgent-start peritoneal dialysis (USPD) or urgent-start haemodialysis (USHD), and to explore the value of peritoneal dialysis (PD) as the emergent dialysis method for elderly patients with ESRD.

DESIGN

Retrospective cohort study.

SETTING

Two tertiary care hospitals in Shanghai, China.

PARTICIPANTS

Chinese patients (n=542) >65 years of age with estimated glomerular filtration rate ≤15 mL/min/m2 who received urgent-start dialysis between 1 January 2005 and 31 December 2015, and with at least 3 months of treatment. Patients who converted to other dialysis methods, regardless of the initial dialysis method, were excluded, as well as those with comorbidities that could significantly affect their dialysis outcomes.

PRIMARY AND SECONDARY OUTCOME MEASURES

Dialysis-related complications and survival were compared. Patients were followed until death, stopped PD, transfer to other dialysis centres, loss to follow-up or 31 December 2016.

RESULTS

There were 309 patients in the USPD group and 233 in the USHD group. The rate of dialysis-related complications within 30 days after catheter implantation was significantly lower in the USPD group compared with the USHD group (4.5% vs 10.7%, p=0.031). The 6-month and 1, 2 and 3-year survival rates were 95.3%, 91.4%, 86.6% and 64.8% in the USPD group, and 92.2%, 85.7%, 70.2% and 57.8% in the USHD group, respectively (p=0.023). The multivariable Cox regression analysis showed that USHD (HR=2.220, 95% CI 1.298 to 3.790; p=0.004), age (HR=1.025, 95% CI 1.013 to 1.043, p<0.001) and hypokalaemia (HR=0.678, 95% CI 0.487 to 0.970; p=0.032) were independently associated with death.

CONCLUSIONS

USPD was associated with slightly better survival compared with USHD. USPD was associated with fewer complications and better survival than USHD in elderly patients with ESRD.

A Call to Arms: Economic Barriers to Optimal Dialysis Care

Epidemic growth rates and the enormous cost of dialysis pressure end-stage renal disease (ESRD) delivery systems around the world. Payers of dialysis services can constrain costs through ( 1 ) limiting access to dialysis, ( 2 ) reducing the quality of dialysis, and ( 3 ) placing constraints on modality distribution. In order to secure the necessary resources for ESRD care, we propose that the nephrology community consider the following suggestions: First, future leaders in dialysis should acquire additional advanced training in innovative pathways such as health care economics, business and health care administration, and health care policy. Second, the international nephrology community must strongly engage in ongoing advocacy for accessible, high quality, cost-effective care. Third, efforts should be made to better define and then implement optimal dialysis modality distributions that maximize patient outcomes but limit unnecessary costs. Fourth, industry should be encouraged to lower the unit cost of dialysis, allowing for improved access to dialysis, especially in developing countries. Fifth, research should be encouraged that seeks to identify measures that will reduce dialysis costs but will not impair quality of care. Finally, early referral of patients with progressive renal disease to nephrology clinics, empowerment of informed patient choice of dialysis modality, and proper and timely access creation should be encouraged and can be expected to help limit overall expenditures. Ongoing efforts in these areas by the nephrology community will be essential if we are to overcome the challenges of ESRD growth in this new decade.

Current Status of Peritoneal Dialysis in Korea: Efforts to Achieve Optimal Outcome

Since its introduction in 1981, peritoneal dialysis (PD) has become firmly established as an effective mode of renal replacement therapy and serves an increasing patient population in Korea. The latest registry data indicate that about 3700 end-stage renal disease patients are maintained on chronic PD, representing 24.1% of the country's dialysis population. The majority (93.3%) of these patients are on continuous ambulatory peritoneal dialysis (CAPD) using the two-bag disconnect system, while only 3.3% are on automated PD. Under current renal reimbursement policies, most dialysis patients have to pay 20% of dialysis fees. Thus CAPD patients on 4 x 2-L daily exchanges pay about US$200 per month, not including medication and travel costs.

Traditionally, most PD centers in Korea have used the “standard” prescription of 4 exchanges of 2 L of solution for most of their patients. A recent survey of 1467 patients who commenced CAPD in 1997 revealed that 84% of these patients were initially prescribed 4 x 2-L exchanges, while 12% were given a daily volume of 6 L. With this standard prescription, the percentages of Korean CAPD patients initially achieving the adequacy target of Kt/V urea ≥ 2.0 and standardized creatinine clearance (SCCr) ≥ 60 L/week/ 1.73 m2, were 74.4% and 82.1%, respectively. It is likely that, among current Korean CAPD patients, a much lower percentage will achieve the clearance targets compared to this initial outcome, but the precise data are not available. However, it is not clear whether the levels of small-solute clearance recommended for optimal PD outcomes, and proposed by the NKF-DOQI guidelines, will bring the expected benefits to Korean patients.

Overall survival of Korean PD patients appears to be as good as, or even better than, that in most other countries. Recently, a single large PD center reported patient survival of 92.1%, 85.6%, 81.4%, and 67.6% at 1, 2, 3, and 5 years respectively. Other centers also reported similar outcomes. As in other countries, cardiovascular deaths predominate among Korean patients: death was due to cardiac causes in 29%, to vascular causes in 21%, and to infectious causes in 24%.

Peritonitis is the most important barrier to prolonged use of CAPD in Korea, and more PD patients transfer to hemodialysis because of peritonitis than in other countries. To further reduce the morbidity and mortality of Korean PD patients, various control measures need to be implemented that can reduce or prevent peritonitis and other infectious complications. Also, to further improve long-term patient outcome, Korean nephrologists need to establish and practice optimal clearance targets in the chronic care of these patients.

Prophylaxis against Gram-Positive Organisms Causing Exit-Site Infection and Peritonitis in Continuous Ambulatory Peritoneal Dialysis Patients by Applying Mupirocin Ointment at the Catheter Exit Site

Objective

We evaluated the effectiveness of local application of mupirocin ointment at the catheter exit site in preventing exit-site infection and peritonitis attributable to gram-positive organisms in continuous ambulatory peritoneal dialysis patients.

Methods

This prospective randomized controlled trial included 154 patients. They were randomly allocated to a mupirocin-treated group (group M) and a control group (group C). Group M included 73 patients (47.4%) who were instructed to apply mupirocin ointment to the catheter exit site once daily after the routine daily exit-site dressing. Group C included 81 patients (52.6%) who continued their usual daily exit-site care without applying mupirocin. The two groups were followed to see whether there would be any difference in the frequency of exit-site infection and peritonitis or in the infecting organisms.

Results

Interim data were collected at 5 months after the start of the study. Those data showed a significantly lower incidence of exit-site infection and peritonitis attributable to gram-positive organisms in group M as compared with group C. The incidence of gram-positive exit-site infection in group C was 1 episode per 36.8 patient–months; in group M, the incidence was 1 episode per ∞ patient–months (0 incidence in 5 months, p < 0.05). The incidence of gram-positive peritonitis in group C was 1 episode per 40.5 patient–months; in group M, the incidence was 1 episode per 365 patient–months ( p < 0.05). Mupirocin treatment had no significant effect on the incidence of exit-site infection and peritonitis attributable to other organisms. Before mupirocin treatment, we saw a trend toward higher infection rates in diabetic patients and nasal carriers of Staphylococcus aureus as compared with non diabetic patients and nasal non carriers, although the differences were not statistically significant. Mupirocin brought the infection rate attributable to gram-positive organisms to an equally low level in diabetic and non-diabetic patients, and in nasal carriers and nasal non carriers of S. aureus. No adverse effect of local application of mupirocin was reported.

Conclusion

Local application of mupirocin ointment at the catheter exit site is a safe and effective method of preventing exit-site infection and peritonitis involving gram-positive organisms.

Socioeconomic Aspects of Peritoneal Dialysis in North America: Role of Non Medical Factors in the Choice of Dialysis

Patients initiating dialysis therapy must make a choice between hemodialysis (HD) and peritoneal dialysis (PD). Controversy persists over the relative merits of each modality in the treatment of end-stage renal disease (ESRD). Issues relating to survival, morbidity, economics, and patient characteristics will all determine the final choice of therapy. Non medical factors are the most important determinant of dialysis modality selection.

In the United States, HD has been the more commonly used modality, while PD is underrepresented. This disparity arises from multiple factors including reactions (sometimes incorrect) to the healthcare financing structure, physician biases, and changing demographic patterns in the ESRD population. We discuss these issues and present collected evidence showing that increased use of PD may have substantial overall benefit.

Patients on Chronic Peritoneal Dialysis for Ten Years or More in North America

Thirty-six patients on peritoneal dialysis (PD) for more than ten years in six North American centers were analyzed retrospectively. In the six centers, the percentage of patients surviving for more than ten years varied between 0.8% and 7.3%. The study group included 27 females and 9 males aged 38.6 ± 14.2 years [mean ± standard deviation (SD)] at the start of treatment. Of the 36 patients, 28 were Caucasian.

The most common cause of end-stage renal disease (ESRD), present in 12 patients, was chronic glomerulonephritis. Only 4 patients had diabetes. At the beginning of the study, 19 patients had hypertension (the most common comorbid condition); 11 had no comorbid conditions at the start.

Creatinine clearance at the start was 4.12 ± 3.5 mL per minute, and the mean duration to anuria was 51 ± 25 months. Mean initial body weight was 55 ± 9 kg, and mean body surface area was 1.5 ± 0.2 m2. Serum albumin levels showed an increase from 33.8 ± 3.6 g/L at the start of the study to 38.2 ± 3.9 g/L at the end.

Hospitalization rate was low at 0.5 ± 0.3 admissions per patient–year, and duration of hospitalization was 4.8 ± 3.7 days per patient–year. Peritonitis was the most common cause of hospitalization. The mean peritonitis rate was 1 episode every 52 ± 48 patient–months.

There were 36 catheter changes in 18 patients; 16 patients had a single PD catheter throughout the period of study. Autonomous hyperparathyroidism was the most common long-term complication.

At the end of the study period, 11 patients were still on PD, 9 had died, 5 had been transferred to hemodialysis (HD), 1 was alive with a functioning allograft, and 1 was lost to follow-up.

We conclude that patients who survive longer than ten years on PD are most likely to be young Caucasian females, small in body size, who are non diabetic, with few comorbid conditions. These long-term survivors have few hospitalizations, and their peritonitis rate is low. In this group of patients, severe autonomous hyperparathyroidism is the most common long-term complication.

Reformulating the Integrated Care Concept for the New Millennium

The concept of integrated care advocates a planned approach to predialysis care. Its components include timely referral to a renal care team, timely preparation for dialysis, and timely initiation of dialysis, with peritoneal dialysis (PD) as the initial therapy for suitable patients. This initial therapy may then be followed by timely transfer to hemodialysis (HD) when residual renal function declines or when other PD-related problems occur.

We argue that at least three problems exist with the integrated care approach as it is currently being articulated. They are ( 1 ) an under emphasis on slowing the rate of progression of chronic kidney disease, aggressive management of cardiovascular risk factors and other comorbidities, and pre-emptive live donor transplantation; ( 2 ) a lack of consideration of home HD as an alternate initial therapy; and ( 3 ) a lack of discussion about patient choice. We propose a modified version of integrated care that we believe will optimize modality distribution and patient outcomes, while reducing the relative costs per patient treated, compared to the current situation in most countries.

Nutritional Markers during Peritoneal Dialysis: Data from the 1998 Peritoneal Dialysis Core Indicators Study

Objective

This analysis explores the nutritional status of adult U.S. peritoneal dialysis (PD) patients.

Design

The Peritoneal Dialysis Core Indicators Study is a prospective cross-sectional prevalence survey describing the care provided to a random sample of adult U.S. PD patients.

Methods and Population

Prevalence data were collected from a national random sample of 1381 adult PD patients participating in the United States End Stage Renal Disease (ESRD) program.

Results

The median age of these patients was 55 years, 61% were Caucasian; the leading cause of ESRD was diabetes mellitus. Age, sex, size, peritoneal permeability, dialysis adequacy, and nutritional indices did not differ between patients on continuous ambulatory PD and patients on automated PD. The dialysis prescriptions employed achieved mean weekly Kt/V urea (wKt/V) and creatinine clearance (wCCr) values of 2.22 ± 0.57 and 67.8 ± 22.5 L/1.73 m2/week, respectively. The PD patients were large, with a mean body weight of 77 ± 21 kg and body mass index (BMI) of 27 ± 8.6 kg/m2. The mean serum albumin of these patients was 3.5 ± 0.51 g/dL, and 43% of values fell below the National Kidney Foundation Dialysis Outcomes Quality Initiative's desired range. The PD patients had a normalized protein equivalent of nitrogen appearance (nPNA) of 1.0 ± 0.57 g/kg/day, a normalized creatinine appearance rate (nCAR) of 17 ± 7.3 mg/kg/day, and an estimated lean body mass (%LBM) of 62% ± 18% of body weight. Serum albumin correlated positively with patient size, nCAR, and nPNA, but negatively with age, the presence of diabetes mellitus, female gender, erythropoietin dose, the creatinine dialysate-to-plasma ratio results of peritoneal equilibration testing, and the dialysis portion of the wCCr. The duration of ESRD experience correlated negatively with both serum albumin and patient size, although these relationships were complex.

Conclusion

Peritoneal dialysis patients generally have marginal serum albumin levels, a finding incongruent with alternative measures of nutritional status, such as weight, BMI, and creatinine generation. Serum albumin is reduced in patients with high peritoneal permeability ( i.e., rapid transporters) and, because these patients generally have higher than average wCCr values, serum albumin is inversely correlated with the dialysis component of the wCCr. The presumptive nutritional indicators (BMI, %LBM, nPNA, and serum albumin) provide disparate estimates, varying from 10% to 50% for the prevalence of nutritionally stressed PD patients.

Optimization of Peritoneal Dialysis Prescription Using Computer Models of Peritoneal Transport

Computer models are valuable clinical tools in the effort to improve quality of life for dialysis patients. At present, two software programs have been validated clinically in adult and pediatric populations. They are the Personal Dialysis Capacity (PDC: Gambro Lundia AB, Lund, Sweden) and PD Adequest (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.). Both programs seem to give accurate predictions of small-solute clearance, but the PDC seems to be superior in predicting ultrafiltration volumes. Indeed, the software programs have several important differences that affect their accuracy and, hence, their clinical value. The PDC software introduces the concepts of capillary physiology to the field of peritoneal dialysis. It gives a functional description of the peritoneal membrane of the individual patient. Recently, its “new” area parameter (A0/Δx) was shown to be superior to the peritoneal equilibration test (PET) in predicting transperitoneal exchange.

Chronic Peritoneal Dialysis in the Elderly: A Review

During the past few decades, the pattern of end-stage renal disease has changed significantly with the emerging predominance of elderly patients. Because this heterogeneous population is characterized by a physiological decline in function of all organs, the nephrologist must contemplate the special needs of individual patients when they develop end-stage renal disease. Before the initiation of dialysis, these patients must be given detailed information to help them select the particular mode that will maximize their quality of life. According to available data, peritoneal dialysis offers some advantages for elderly patients, such as hemodynamic stability, steady-state metabolic control, good control of hypertension, independence from hospital, and avoidance of repeated vascular access. Early referral promotes the establishment of peritoneal access and minimizes the consequences of uremia, subsequent morbidity, and frequent hospitalization. Elderly patients are compliant and highly motivated to cooperate with their treatment. They have no higher modality-related complications than younger patients and their quality of life is satisfactory. Although most have comorbid conditions that interfere with self-performance of dialysis, such as impaired vision and reduced physical and mental activity, they can perform peritoneal dialysis successfully if they have a high level of family support. Patients who do not have family support may have successful peritoneal dialysis if they have access to a network of medical and social support, that is, private home nurses, rehabilitation and chronic care dialysis units, or nursing homes.

The Role of Peritoneal Dialysis as the First-Line Renal Replacement Modality

Twenty years after its introduction, peritoneal dialysis (PD) is a well-established alternative to hemodialysis (HD) as a modality of renal replacement therapy. Much debate and research is apparent in the literature, comparing hemodialysis and PD as “opposite” modalities and trying to ascertain which modality should be more optimal.

In our opinion, HD and PD are two distinct modalities, each with its own advantages and disadvantages. In addition, it is clear that for both HD and PD, rates of technique failure are high, causing patients to transfer between modalities. The question is thus not which modality is best, but rather, which flow-chart of modalities makes best use of the advantages of each modality, while avoiding its disadvantages. In this respect, HD and PD appear to be complementary modalities.

The better preservation of residual renal function, lower risk of infection with hepatitis B and C, better outcome after transplantation, preservation of vascular access, and lower costs are arguments to promote PD as a good initial treatment. When PD-related problems arise (adequacy, ultrafiltration, peritonitis, patient burnout), a timely transfer to HD has to be planned.

This editorial tries to review arguments supporting the complementary nature of both modalities, and especially the role of PD as the first-line renal replacement therapy.