US Renal Data System 2018 Annual Data Report: Epidemiology of Kidney Disease in the United States

COVID-19 in Chronic Kidney Disease: The Impact of Old and Novel Cardiovascular Risk Factors

Cardiovascular disease is a frequent complication and the most common cause of death in patients with CKD. Despite landmark medical advancements, mortality due to cardiovascular disease is still 20 times higher in CKD patients than in the general population, which is mainly due to the high prevalence of risk factors in this group. Indeed, in addition to traditional cardiovascular risk factors, CKD patients are exposed to nontraditional ones, which include metabolic, hormonal, and inflammatory alterations. The global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has brought novel challenges for both cardiologists and nephrologists alike. Emerging evidence indicates that coronavirus disease 2019 (COVID-19) increases the risk of cardiovascular events and that several aspects of the disease may synergize with pre-existing cardiovascular risk factors in CKD patients. A better understanding of these mechanisms is pivotal for the prevention and treatment of cardiovascular events in this context, and we believe that additional clinical and experimental studies are needed to improve cardiovascular outcomes in CKD patients with COVID-19. In this review, we provide a summary of traditional and nontraditional cardiovascular risk factors in CKD patients, discussing their interaction with SARS-CoV-2 infection and focusing on CO-VID-19-related cardiovascular complications that may severely affect short- and long-term outcomes in this high-risk population.

Potassium Trajectories prior to Dialysis and Mortality following Dialysis Initiation in Patients with Advanced CKD

INTRODUCTION

Patients with advanced non-dialysis-dependent CKD (NDD-CKD) have a reduced ability for maintaining plasma potassium (K) in normal range. Deviation from normal plasma K ranges is associated with increased mortality; however, the average trajectory of plasma K over time in patients with advanced NDD-CKD and the outcomes associated with plasma K trajectory are unknown.

METHODS

We identified 34,167 US veterans with advanced NDD-CKD transitioning to dialysis between October 2007 and March 2015 with at least 1 K measurement each year over a 3-year period prior to dialysis transition (3-year prelude). The K trajectory defined as the change in K (slope) per year over the entire 3-year prelude was estimated using linear mixed-effects models. The association between unadjusted (crude) K slope (categorized as stable [-0.09 to 0.09 mEq/L/year], decreasing [≤-0.10 mEq/L/year], and increasing [≥0.10 mEq/L/year]) and time to all-cause and cardiovascular mortality during the 6 months following dialysis initiation was assessed using multivariable-adjusted survival models.

RESULTS

The crude and multivariable-adjusted K slopes (mean, 95% CI) over the 3-year prelude were 0.008 (0.0059, 0.0110) and -0.15 mEq/L/year (-0.19, -0.11), respectively. Decreasing K slope was associated with higher multivariable-adjusted risk of all-cause mortality (adjusted hazard ratio [95% CI] vs. stable K slope: 1.08 [1.00-1.17]). No association was observed between K slope and cardiovascular mortality.

DISCUSSION/CONCLUSION

The average intraindividual plasma K trajectory is remarkably stable in patients with advanced NDD-CKD. A decreasing K slope is associated with higher all-cause mortality risk.

Assessing Nephrology Fellows' Skills in Communicating About Kidney Replacement Therapy and Kidney Biopsy: A Multicenter Clinical Simulation Study on Breaking Bad News

RATIONALE & OBJECTIVE

Interpersonal communication skills and professionalism competencies are difficult to assess among nephrology trainees. We developed a formative "Breaking Bad News" simulation and implemented a study in which nephrology fellows were assessed with regard to their skills in providing counseling to simulated patients confronting the need for kidney replacement therapy (KRT) or kidney biopsy.

STUDY DESIGN

Observational study of communication competency in the setting of preparing for KRT for kidney failure, for KRT for acute kidney injury (AKI), or for kidney biopsy.

SETTING & PARTICIPANTS

58 first- and second-year nephrology fellows assessed during 71 clinical evaluation sessions at 8 training programs who participated in an objective structured clinical examination of simulated patients in 2017 and 2018.

PREDICTORS

Fellowship training year and clinical scenario.

OUTCOME

Primary outcome was the composite score for the "overall rating" item on the Essential Elements of Communication-Global Rating Scale 2005 (EEC-GRS), as assessed by simulated patients. Secondary outcomes were the score for EEC-GRS "overall rating" item for each scenario, score < 3 for any EEC-GRS item, Mini-Clinical Examination Exercise (Mini-CEX) score < 3 on at least 1 item (as assessed by faculty), and faculty and fellow satisfaction with simulation exercise (via a survey they completed).

ANALYTICAL APPROACH

Nonparametric tests of hypothesis comparing performance by fellowship year (primary goal) and scenario.

RESULTS

Composite scores for EEC-GRS overall rating item were not significantly different between fellowship years (P = 0.2). Only 4 of 71 fellow evaluations had an unsatisfactory score for the EEC-GRS overall rating item on any scenario. On Mini-CEX, 17% scored < 3 on at least 1 item in the kidney failure scenario; 37% and 53% scored < 3 on at least 1 item in the AKI and kidney biopsy scenarios, respectively. In the survey, 96% of fellows and 100% of faculty reported the learning objectives were met and rated the experience good or better in 3 survey rating questions.

LIMITATIONS

Relatively brief time for interactions; limited familiarity with and training of simulated patients in use of EEC-GRS.

CONCLUSIONS

The fellows scored highly on the EEC-GRS regardless of their training year, suggesting interpersonal communication competency is achieved early in training. The fellows did better with the kidney failure scenario than with the AKI and kidney biopsy scenarios. Structured simulated clinical examinations may be useful to inform curricular choices and may be a valuable assessment tool for communication and professionalism.

KDOQI US Commentary on the 2020 KDIGO Clinical Practice Guideline on the Evaluation and Management of Candidates for Kidney Transplantation

Evaluation of patients for kidney transplant candidacy is a comprehensive process that involves a detailed assessment of medical and surgical issues, psychosocial factors, and patients' physical and cognitive abilities with an aim of balancing the benefits of transplantation and potential risks of surgery and long-term immunosuppression. There is considerable variability among transplant centers in their approach to evaluation and decision-making regarding transplant candidacy. The 2020 KDIGO (Kidney Disease: Improving Guidelines Outcome) clinical practice guideline on the evaluation and management of candidates for kidney transplantation provides practice recommendations that can serve as a useful reference guide to transplant professionals. The guideline, covering a broad range of topics, was developed by an international group of experts from transplant and nephrology through a review of literature published until May 2019. A work group of US transplant nephrologists convened by NKF-KDOQI (National Kidney Foundation-Kidney Disease Quality Initiative) chose key topics for this commentary with a goal of presenting a broad discussion to the US transplant community. Each section of this article has a summary of the key KDIGO guideline recommendations, followed by a brief commentary on the recommendations, their clinical utility, and potential implementation challenges. The KDOQI work group agrees broadly with the KDIGO recommendations but also recognizes and highlights the decision-making challenges that arise from lack of high-quality evidence and the need to balance equity with utility of organ transplantation.

Association of mineral metabolism biomarkers with chronic kidney disease in Chinese adults

Background

We aimed to examine the association of three mineral metabolism markers, including serum calcium, inorganic phosphorus, and intact parathyroid hormone with the risk of chronic kidney disease (CKD) at all stages.

Methods

This retrospective cohort study involved 3563 participants, including 3274 CKD patients and 289 healthy controls. CKD is diagnosed according to clinical guidelines from the 2012 KDIGO. Effect sizes are expressed odds ratio (OR) and 95 confidence interval (CI).

Results

After propensity score matching, per 0.5 mg/dL increment of inorganic phosphorus was significantly associated with 1.33-, 1.61-, and 2.85-fold increased risk of CKD at stages 1–2, 4, and 5, respectively. Regarding per 8 pg/mL increment of intact parathyroid hormone, significance was only noted for stage 5. In subsidiary analyses, the risk prediction of mineral metabolism markers under study was more evident in males and hypertensive subjects. A nomogram prediction model was constructed based on age, sex, and three mineral metabolism markers for CKD, with decent accuracy.

Conclusions

Our findings indicate that serum calcium was associated with all-stage CKD risk, whereas the association for inorganic phosphorus and intact parathyroid hormone was significant at advanced stages.

The need for a cardionephrology subspecialty

Chronic kidney disease (CKD) has structural and functional repercussions for the cardiovascular system that facilitate the development of cardiovascular disease (CVD). In fact, cardiovascular complications are frequent in the CKD population and thus cause a great clinical, public health and economic burden. Despite this challenge, the prevention and management of cardiovascular complications is one among several aspects of CKD that meets the criteria of an unmet medical need. This probably has to do with the misperception by the nephrologist of the global relevance of CVD in the CKD patient which, in turn, may be due to insufficient cardiovascular training during nephrology specialization. Therefore a change in approach is necessary to understand CKD as a disease in which the manifestations and complications related to CVD become so frequent and important that they require dedicated multidisciplinary clinical management. From this perspective, it makes sense to consider training in the subspecialty of cardionephrology to provide adequate cardiovascular care for CKD patients by the nephrologist. In addition, the cardionephrology subspecialist would be better able to interact with other specialists in multidisciplinary care settings created to achieve a deeper understanding and more effective clinical handling of the interactions between CKD and CVD.

Kidney Health for Everyone Everywhere - From prevention to detection and equitable access to care

The global burden of chronic kidney disease (CKD) is rapidly increasing with a projection of becoming the 5th most common cause of years of life lost globally by 2040. Aggravatingly, CKD is a major cause of catastrophic health expenditure. The costs of dialysis and transplantation consume up to 3% of the annual healthcare budget in high-income countries. Crucially, however, the onset and progression of CKD is often preventable. In 2020, the World Kidney Day campaign highlights the importance of preventive interventions - be it primary, secondary or tertiary. This complementing article focuses on outlining and analyzing measures that can be implemented in every country to promote and advance CKD prevention. Primary prevention of kidney disease should focus on the modification of risk factors and addressing structural abnormalities of the kidney and urinary tracts, as well as exposure to environmental risk factors and nephrotoxins. In persons with pre-existing kidney disease, secondary prevention, including blood pressure optimization and glycemic control, should be the main goal of education and clinical interventions. In patients with advanced CKD, management of co-morbidities such as uremia and cardiovascular disease is a highly recommended preventative intervention to avoid or delay dialysis or kidney transplantation. Political efforts are needed to proliferate the preventive approach. While national policies and strategies for non-communicable diseases might be present in a country, specific policies directed toward education and awareness about CKD screening, management and treatment are often lacking. Hence, there is an urgent need to increase the awareness of the importance of preventive measures throughout populations, professionals and policy makers.

The long-term prognostic factors in hemodialysis patients with acute coronary syndrome: perspectives from sarcopenia and malnutrition

Hemodialysis (HD) patients tend to have sarcopenia and malnutrition, and both conditions are related to poor prognosis in the cardiovascular disease that often accompanies HD. However, the impact of sarcopenia or malnutrition on the long-term prognosis of HD patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) remains unclear. We analyzed 1,605 consecutive patients with ACS who had undergone PCI at a single center between January 2009 and December 2014. We evaluated all-cause mortality and prognosis-associated factors, including sarcopenia/malnutrition-related factors such as the Geriatric Nutritional Risk Index (GNRI), and Skeletal Muscle Mass Index (SMI). After exclusions, 1461 patients were enrolled, and 58 (4.0%) were on HD. The HD group had lower levels of SMI and GNRI than non-HD group, and had worse in-hospital prognosis. Moreover, HD group had a significant higher mortality in the long-term follow-up [median follow-up period: 1219 days; Hazard Ratio (HR) = 4.09, p < 0.001]. After adjusting the covariates, SMI and GNRI were the factors associated with all-cause mortality in all patients [SMI: adjusted HR (aHR) = 2.39, p = 0.036; GNRI: aHR = 2.21, p = 0.006]; however, these findings were not observed among HD patients with ACS, and only diabetes was significantly associated with all-cause mortality (diabetes: aHR = 3.50, p = 0.031). HD patients with ACS had a significantly higher rate of in-hospital and long-term mortality than non-HD patients. Although sarcopenia and malnutrition were related to mortality and were more common in HD patients, sarcopenia and malnutrition had a lower impact than diabetes on the long-term prognosis of HD patients with ACS.

Elevated levels of soluble ST2 but not galectin-3 are associated with increased risk of mortality in hemodialysis patients

Background

The soluble forms of suppression of tumorigenicity-2 (ST2) and galectin-3 have been proposed as novel biomarkers for cardiac fibrosis and heart failure, as well as predictors of cardiovascular events and mortality. However, there are limited data on the association between soluble ST2 and galectin-3 and clinical outcomes in patients with kidney failure on replacement therapy. To determine this, we examined the associations between soluble ST2 and galectin-3 and all-cause mortality and cardiovascular events in patients on hemodialysis.

Methods

This study included maintenance hemodialysis patients (over 18 years old) who consented to preserve their serum in the Biobank at our institution between March 2014 and March 2015. We used Cox proportional hazards regression analysis to evaluate the associations between soluble ST2, galectin-3 levels, and clinical outcomes. The primary outcome was all-cause mortality, the secondary outcome was cardiovascular disease, and patients were followed for both outcomes until March 2018.

Results

A total of 296 patients were analyzed in this study. The mean age was 57 ± 13 years, and 53.0% were male. Serum concentration of soluble ST2 was significantly associated with higher mortality, after adjustment for confounding factors, but was not associated with cardiovascular disease. Serum galectin-3 level was not independently associated with either outcome after adjustment.

Conclusion

Elevated soluble ST2 is independently associated with an increased risk of mortality, but not with cardiovascular disease, in patients on hemodialysis. Elevated galectin-3 was not associated with mortality or cardiovascular disease.

Culture and analysis of kidney tubuloids and perfused tubuloid cells-on-a-chip

Advanced in vitro kidney models are of great importance to the study of renal physiology and disease. Kidney tubuloids can be established from primary cells derived from adult kidney tissue or urine. Tubuloids are three-dimensional multicellular structures that recapitulate tubular function and have been used to study infectious, malignant, metabolic, and genetic diseases. For tubuloids to more closely represent the in vivo kidney, they can be integrated into an organ-on-a-chip system that has a more physiological tubular architecture and allows flow and interaction with vasculature or epithelial and mesenchymal cells from other organs. Here, we describe a detailed protocol for establishing tubuloid cultures from tissue and urine (1-3 weeks), as well as for generating and characterizing tubuloid cell-derived three-dimensional tubular structures in a perfused microfluidic multi-chip platform (7 d). The combination of the two systems yields a powerful in vitro tool that better recapitulates the complexity of the kidney tubule with donor-specific properties.

Systematic Review and Meta-analysis of Herpes Zoster Vaccine in Patients With CKD

Introduction

Chronic kidney disease (CKD) is a risk factor for herpes zoster (HZ) infection. Few studies have examined HZ vaccine (HZV) in this population. We conducted a systematic review and meta-analysis investigating the efficacy and safety of HZV in patients with renal disease (CKD, dialysis, and transplant).

Methods

MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases (up to May 2020) were searched for randomized controlled trials and nonrandomized controlled studies evaluating HZV in patients with CKD for effectiveness and adverse event risks. Studies without a control group (placebo or no vaccine) were excluded. Extraction of prespecified data and risk of bias assessments using the Newcastle-Ottawa scale for cohort studies and the Cochrane Risk of Bias Tool for randomized controlled trials were done by 3 authors. Random-effects meta-analysis was used to generate pooled treatment effects and 95% confidence intervals.

Results

Included were 404,561 individuals from 8 studies (3 randomized controlled trials and 5 nonrandomized). All 8 studies examined HZ as an outcome, with 3 reporting adverse events. Risk of HZ was lower in patients who received HZV compared with controls (hazard ratio, 0.55; 95% confidence interval, 0.37–0.82; P < 0.01); however, heterogeneity was high (I² = 88%, P < 0.01). There was no significant difference in adverse events associated with HZV (hazard ratio, 1.03; 95% confidence interval, 0.54–1.28; P = 0.8).

Conclusions

HZV compared with control significantly lowers the risk of HZ without an increase in adverse events in CKD patients. However, significant heterogeneity was present. HZV should be actively considered in CKD patients because the prevalence of HZ is higher in this population.

Hepatitis B virus vaccine and chronic kidney disease. The advances

BACKGROUND

Hepatitis B is an important agent of liver disease in patients with chronic kidney disease and chronic HBV infection promotes the development of CKD in the adult general population. Patients with CKD have a suboptimal response to various vaccines, and it remains unclear how we boost the immune response of CKD patients to HB vaccine.

STUDY AIMS AND DESIGN

We performed a narrative review to assess the mechanisms of lower immunogenicity of HBV vaccine in CKD population; multiple approaches to improve the response rate of CKD patients to HBV vaccine have been reported. This is a very important topic for nephrologists who often serve as primary case providers for patients with CKD.

RESULTS

The recommended vaccine schedule for CKD patients including those on maintenance dialysis is based on recombinant vaccine, four doses (month 0,1,2, and 6; 40mcg each) by intramuscular route (deltoid muscle). According to RCTs or observational studies, some recombinant vaccines with adjuvants (i.e., HBV-AS02 and HBV-AS04) look promising. HBV-AS04 showed to give better seroprotection rates and durable immune response over extended follow-ups compared with licensed HBV vaccine in CKD patients. The seroprotection rate was 95% (97/102) and 82% (202/248) in pre-dialysis and dialysis patients, respectively, one month after completing vaccine schedule with HBV-AS04. HBV-AS02 was superior to licensed vaccine in terms of seroprotection rate, 76.9% vs. 37.6%.

CONCLUSIONS

We suggest adjuvanted recombinant (HBV-AS04) vaccine (0,1,2 and 3 months; 20 mcg each dose) and post vaccination testing of anti-HBs antibody after vaccination. Booster doses to patients whose anti-HBs titers fall below the seroprotection level (<10IU/mL) during the follow-up are appropriate. The patho-physiologic mechanisms responsible for the poor immunogenicity of HBV vaccine in CKD patients are under active investigation.

Nocturnal Hemodialysis: Why Aren't More People Doing It?

Nocturnal hemodialysis is a form of intensive hemodialysis, which may be done in center or at home. Despite the documented clinical and economic benefits of ncturnal hemodialysis, uptake of this modality has been relatively low. In this review, we aim to address the potential barriers and possible mitigation strategies. Among the patient-related barriers, lack of knowledge and awareness remains the most common barrier, while administrative inertia to change from conventional in-center hemodialysis continues to be a challenge. Current global effort to grow home dialysis will re-focus the need for better patient education, innovate home dialysis technology, and evolve new models of care. New patient-focused policy will allow changes in reimbursement and develop appropriate momentum toward an integrated "home first model" to kidney replacement therapy.

Roxadustat for Treating Anemia in Patients with CKD Not on Dialysis: Results from a Randomized Phase 3 Study

BACKGROUND

Current anemia therapies for patients with non-dialysis-dependent CKD may require injection and medical visits. Roxadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, stimulates erythropoiesis and improves iron homeostasis.

METHODS

In this double-blind phase 3 study, we randomized patients with non-dialysis-dependent CKD stages 3-5 and hemoglobin <10.0 g/dl (1:1) to thrice-weekly 70-mg oral roxadustat or placebo. Doses were titrated throughout the study based on hemoglobin levels. The primary efficacy end point was mean change from baseline in hemoglobin averaged over weeks 28-52 versus placebo, irrespective of rescue therapy use. We assessed patients for adverse events.

RESULTS

The study included 2781 patients, 1393 who received roxadustat and 1388 who received placebo. Mean baseline hemoglobin was 9.1 g/dl for both groups. The mean change in hemoglobin from baseline was 1.75 g/dl (95% confidence interval [95% CI], 1.68 to 1.81) with roxadustat versus 0.40 g/dl (95% CI, 0.33 to 0.47) with placebo, (P<0.001). Among 411 patients with baseline elevated high-sensitivity C-reactive protein, mean change in hemoglobin from baseline was 1.75 g/dl (95% CI, 1.58 to 1.92) with roxadustat versus 0.62 g/dl (95% CI, 0.44 to 0.80) with placebo, (P<0.001). Roxadustat reduced the risk of red blood cell transfusion by 63% (hazard ratio, 0.37; 95% CI, 0.30 to 0.44). The most common adverse events with roxadustat and placebo, respectively, were ESKD (21.0% versus 20.5%), urinary tract infection (12.8% versus 8.0%), pneumonia (11.9% versus 9.4%), and hypertension (11.5% versus 9.1%).

CONCLUSIONS

Roxadustat effectively increased hemoglobin in patients with non-dialysis-dependent CKD and reduced the need for red blood cell transfusion, with an adverse event profile comparable to that of placebo.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Safety and Efficacy Study of Roxadustat to Treat Anemia in Patients With CKD, Not on Dialysis, NCT02174627.

Comparison of Ellipsys Percutaneous and Proximal Forearm Gracz-Type Surgical Arteriovenous Fistulas

RATIONALE & OBJECTIVE

Percutaneous arteriovenous fistulas (AVF) are created by establishing a proximal forearm anastomosis and offer a safe and reliable vascular access. This study compares the Ellipsys percutaneous AVF with a proximal forearm Gracz-type surgical AVF, chosen for comparison as it is constructed at the same anatomical site.

STUDY DESIGN

Retrospective study of prospectively collected clinical data.

SETTING & PARTICIPANTS

All vascular access procedures conducted during a 34-month period were reviewed. The study groups comprised 89 percutaneous AVFs and 69 surgical AVFs.

EXPOSURE

Percutaneous or surgical AVF placement.

OUTCOME

AVF patency, function, and complications.

ANALYTICAL APPROACH

Patency rates for each AVF group were evaluated by competing risk survival analysis using a cumulative incidence function. Association of primary, primary assisted, and secondary patency with the AVF groups was examined by Cox proportional hazard models.

RESULTS

Technical success was 100% for both groups. Average procedure times were 14 minutes for percutaneous AVFs and 74 minutes for surgical AVFs (P < 0.001). Proximal radial artery (PRA) was used in all percutaneous AVF cases. Inflow for surgical AVFs included radial (30%), ulnar (12%), and brachial (58%) arteries. Outflow veins for both groups were the cephalic and/or basilic veins. Access flow volumes, times to maturation, and overall numbers of interventions per patient-year were not significantly different. Cumulative incidence of primary patency failure at 12 months was lower for surgical AVF (47% vs 64%, P = 0.1), but secondary patency failure was not different between groups (20% vs 12%, P = 0.3). PRA surgical AVFs had similar primary patency (65% vs 64%, P = 0.8) but higher secondary patency failure rates than percutaneous AVFs at 12 months (34% vs 12%, P = 0.04).

LIMITATIONS

Retrospective study with a relatively short follow-up period, and not all patients required hemodialysis at the end of study.

CONCLUSIONS

Both percutaneous and surgical AVFs demonstrated high rates of technical success and secondary patency. Percutaneous AVFs required shorter procedure times. The rate of intervention was similar. When a distal radial artery AVF is not feasible, percutaneous AVF might offer an appropriate procedure for creating a safe and functional access, maintaining further proximal forearm surgical AVF creation options.

Hepatitis B virus vaccine and chronic kidney disease. The advances

BACKGROUND

Hepatitis B is an important agent of liver disease in patients with chronic kidney disease and chronic HBV infection promotes the development of CKD in the adult general population. Patients with CKD have a suboptimal response to various vaccines, and it remains unclear how we boost the immune response of CKD patients to HB vaccine.

STUDY AIMS AND DESIGN

We performed a narrative review to assess the mechanisms of lower immunogenicity of HBV vaccine in CKD population; multiple approaches to improve the response rate of CKD patients to HBV vaccine have been reported. This is a very important topic for nephrologists who often serve as primary case providers for patients with CKD.

RESULTS

The recommended vaccine schedule for CKD patients including those on maintenance dialysis is based on recombinant vaccine, four doses (month 0,1,2, and 6; 40mcg each) by intramuscular route (deltoid muscle). According to RCTs or observational studies, some recombinant vaccines with adjuvants (i.e., HBV-AS02 and HBV-AS04) look promising. HBV-AS04 showed to give better seroprotection rates and durable immune response over extended follow-ups compared with licensed HBV vaccine in CKD patients. The seroprotection rate was 95% (97/102) and 82% (202/248) in pre-dialysis and dialysis patients, respectively, one month after completing vaccine schedule with HBV-AS04. HBV-AS02 was superior to licensed vaccine in terms of seroprotection rate, 76.9% vs. 37.6%.

CONCLUSIONS

We suggest adjuvanted recombinant (HBV-AS04) vaccine (0,1,2 and 3 months; 20 mcg each dose) and post vaccination testing of anti-HBs antibody after vaccination. Booster doses to patients whose anti-HBs titers fall below the seroprotection level (<10IU/mL) during the follow-up are appropriate. The patho-physiologic mechanisms responsible for the poor immunogenicity of HBV vaccine in CKD patients are under active investigation.

The Interplay Between Thyroid Dysfunction and Kidney Disease

Hypothyroidism is a highly prevalent endocrine complication in chronic kidney disease (CKD) patients. A large body of evidence has shown that there is a bidirectional relationship between thyroid dysfunction and kidney disease, yet there are many remaining gaps in knowledge in regards to the clinical management of CKD patients with hypothyroidism, including those receiving hemodialysis and peritoneal dialysis. Given that hypothyroidism has been associated with many deleterious outcomes including a higher risk of (1) mortality, (2) cardiovascular disease, (3) impaired health-related quality of life, and (4) altered body composition in both non-CKD and CKD patients, future research is needed to establish the appropriate screening, diagnosis, and treatment approaches in these populations.

Analysis of Serum Fatty Acids Profile in Kidney Transplant Recipients

Patients with end-stage kidney disease, treated with renal transplantation, are at increased risk of cardio-vascular disease (CVD) and cardio-vascular mortality. They are also characterized by an atherogenic dyslipidemia. Alterations of the fatty acids (FA) profile contribute to increased cardio-vascular risk in the general population. In the current study we test the hypothesis that kidney transplantation is associated with ab-normalities in FA profile. FA profile was analysed by gas chromatography–mass spectrometry in 198 renal transplant recipients, and 48 control subjects. The most profound differences between renal transplant patients and controls were related to the content of branched chain FA, monounsaturated FA, and n-6 polyunsaturated FA, respectively. The FA profile significantly separated the patients from the controls in the principal component analysis (PCA). The abnormalities of FA profile showed a tendency for normalization in long-term kidney recipients, as compared to patients with recent transplants. The n-3 PUFA content demonstrated a strong inverse association with the presence of inflammation. Most profound alterations of the FA profile were observed in patients with impaired graft function (glomerular filtration rate < 45 mL/min). The study demonstrated significant disorders of the FA profile in kidney transplant recipients, that might contribute to cardio-vascular risk in this vulnerable patient population.

The use of virtual physician mentoring to enhance home dialysis knowledge and uptake

Home dialysis therapies are flexible kidney replacement strategies with documented clinical benefits. While the incidence of end-stage kidney disease continues to increase globally, the use of home dialysis remains low in most developed countries. Multiple barriers to providing home dialysis have been noted in the published literature. Among known challenges, gaps in clinician knowledge are potentially addressable with a focused education strategy. Recent national surveys in the United States and Australia have highlighted the need for enhanced home dialysis knowledge especially among nephrologists who have recently completed training. Traditional in-person continuing professional educational programmes have had modest success in promoting home dialysis and are limited by scale and the present global COVID-19 pandemic. We hypothesize that the use of a 'Hub and Spoke' model of virtual home dialysis mentorship for nephrologists based on project ECHO would support home dialysis growth. We review the home dialysis literature, known educational gaps and plausible educational interventions to address current limitations in physician education.

Child-to-adult body mass index trajectories and the risk of subclinical renal damage in middle age

BACKGROUND

Although it is well established that obesity is a risk factor for chronic kidney disease, the impact of distinct long-term body mass index (BMI) developmental patterns on renal function in later life is poorly understood.

METHODS

This study utilized data derived from the Hanzhong Adolescent Hypertension Cohort, a prospective cohort followed over 30 years. We used latent class growth mixture modeling method to identify the BMI trajectories of participants who had received BMI measurements at least three times from childhood (age: 6-15 years) to adulthood (age: 36-45 years). The modified Poisson regression model was used to identify potential associations between BMI trajectories and subclinical renal damage (SRD) in midlife.

RESULTS

Within a total of 2162 individuals, we identified four distinct long-term BMI trajectories: stable normal (54.72%), moderately increasing overweight (32.42%), resolving (10.27%), and progressively increasing obese (2.59%). By the latest follow-up in 2017, a total of 257 (13.1%) individuals were diagnosed with SRD. Compared with the stable normal group, the moderately increasing overweight group and the progressively increasing obese group exhibited significantly a higher urinary albumin-to-creatinine ratio and a higher odd of existing SRD in 2017 (risk ratio [RR], 1.70 [95% confidence interval (CI), 1.33-2.19] and 4.35 [95% CI, 3.00-6.30], respectively). However, individuals who resolved their elevated BMI in early life had a similar risk for SRD as those who had never been obese or overweight (RR, 1.17 [95% CI, 0.77-1.79]).

CONCLUSIONS

Child-to-adult BMI trajectories that worsen or persist at high levels were associated with an increased risk for SRD in midlife. Maintaining a normal BMI or reversing an elevated BMI in early life may be beneficial to renal function over the long term.

Texture Analysis of Native T1 Images as a Novel Method for Noninvasive Assessment of Uremic Cardiomyopathy

BACKGROUND

Noncontrast cardiac T₁ times are increased in dialysis patients which might indicate fibrotic alterations in uremic cardiomyopathy.

PURPOSE

To explore the application of the texture analysis (TA) of T₁ images in the assessment of myocardial alterations in dialysis patients.

STUDY TYPE

Case-control study.

POPULATION

A total of 117 subjects, including 22 on hemodialysis, 44 on peritoneal dialysis, and 51 healthy controls.

FIELD STRENGTH

A 3 T, steady-state free precession (SSFP) sequence, modified Look-Locker imaging (MOLLI).

ASSESSMENT

Two independent, blinded researchers manually delineated endocardial and epicardial borders of the left ventricle (LV) on midventricular T₁ maps for TA.

STATISTICAL TESTS

Texture feature selection was performed, incorporating reproducibility verification, machine learning, and collinearity analysis. Multivariate linear regressions were performed to examine the independent associations between the selected texture features and left ventricular function in dialysis patients. Texture features' performance in discrimination was evaluated by sensitivity and specificity. Reproducibility was estimated by the intraclass correlation coefficient (ICC).

RESULTS

Dialysis patients had greater T₁ values than normal (P < 0.05). Five texture features were filtered out through feature selection, and four showed a statistically significant difference between dialysis patients and healthy controls. Among the four features, vertical run-length nonuniformity (VRLN) had the most remarkable difference among the control and dialysis groups (144 ± 40 vs. 257 ± 74, P < 0.05), which overlap was much smaller than Global T₁ times (1268 ± 38 vs. 1308 ± 46 msec, P < 0.05). The VRLN values were notably elevated (cutoff = 170) in dialysis patients, with a specificity of 97% and a sensitivity of 88%, compared with T₁ times (specificity = 76%, sensitivity = 60%). In dialysis patients, VRLN was significantly and independently associated with left ventricular ejection fraction (P < 0.05), global longitudinal strain (P < 0.05), radial strain (P < 0.05), and circumferential strain (P < 0.05); however, T₁ was not.

DATA CONCLUSION

The texture features obtained by TA of T₁ images and VRLN may be a better parameter for assessing myocardial alterations than T₁ times.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 3.

Illness perception in patients with chronic kidney disease and kidney failure: a scoping review protocol

INTRODUCTION

Patient education is a crucial component in the management of chronic kidney disease (CKD); however, many education programmes do not tailor to patients' disease-related belief and emotional reactions. According to Leventhal's self-regulation model, such beliefs and reactions, known as illness perceptions, are a part of patients' understanding of their disease and treatment-related actions. The existing research of illness perception in the field of nephrology has been heterogenous in terms of study outcomes and in study population; and the evidence of how illness perceptions affect behavioural and decisional outcomes is limited. This scoping review aims to map and summarise the evidence of published literature on illness perception among patients with CKD not yet treated by dialysis and kidney failure.

METHODS AND ANALYSIS

This study bases its approach on Joanna Brigg's Institute Guidelines on scoping review methods. The search strategy was developed together with a medical information specialist. Searches will be performed on acceptance of publication in the following databases: PubMed, EMBASE, PsycINFO via Ovid, Scopus and the Cumulative Index to Nursing and Allied Health Literature. Searches will be run without incorporating a date restriction in order to capture content from the databases' inception to present day. Search terms including 'illness perception', 'kidney disease' and 'kidney failure' will be screened in titles and abstracts. Two independent researchers will screen the abstracts and full text for full eligibility. We will include studies focusing on illness perception of patients with CKD with estimated glomerular filtration rate <60 mL/min/1.73 m2, kidney failure or recipients of kidney transplant. We will exclude patients <18 years of age, patients with acute kidney injury and non-English articles. All demographic data, study design and study findings will be collected and analysed using a data abstraction tool.

ETHICS AND DISSEMINATION

This study does not require internal review board approval. We will present the findings of this scoping review in a peer-reviewed journal.

Mortality in Children Treated With Maintenance Peritoneal Dialysis: Findings From the International Pediatric Peritoneal Dialysis Network Registry

RATIONALE & OBJECTIVE

Research on pediatric kidney replacement therapy (KRT) has primarily focused on Europe and North America. In this study, we describe the mortality risk of children treated with maintenance peritoneal dialysis (MPD) in different parts of the world and characterize the associated demographic and macroeconomic factors.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Patients younger than 19 years at inclusion into the International Pediatric Peritoneal Dialysis Network registry, who initiated MPD between 1996 and 2017.

EXPOSURE

Region as primary exposure (Asia, Western Europe, Eastern Europe, Latin America, North America, and Oceania). Other demographic, clinical, and macroeconomic (4 income groups based on gross national income) factors also were studied.

OUTCOME

All-cause MPD mortality.

ANALYTICAL APPROACH

Patients were observed for 3 years, and the mortality rates in different regions and income groups were calculated. Cause-specific hazards models with random effects were fit to calculate the proportional change in variance for factors that could explain variation in mortality rates.

RESULTS

A total of 2,956 patients with a median age of 7.8 years at the start of KRT were included. After 3 years, the overall probability of death was 5%, ranging from 2% in North America to 9% in Eastern Europe. Mortality rates were higher in low-income countries than in high-income countries. Income category explained 50.1% of the variance in mortality risk between regions. Other explanatory factors included peritoneal dialysis modality at start (22.5%) and body mass index (11.1%).

LIMITATIONS

The interpretation of interregional survival differences as found in this study may be hampered by selection bias.

CONCLUSIONS

This study shows that the overall 3-year patient survival on pediatric MPD is high, and that country income is associated with patient survival.

Cost-effectiveness analysis of renal replacement therapy strategies in Guangzhou city, southern China

OBJECTIVES

This study aims to assess the cost-effectiveness of three renal replacement therapy (RRT) modalities as well as proposed changes of scheduled policies in RRT composition in Guangzhou city.

METHODS

From a payer perspective, we designed Markov model-based cost-effectiveness analyses to compare the cost-effectiveness of three RRT modalities and four different scheduled policies to RRT modalities in Guangzhou over three time horizons (5, 10 and 15 years). The current situation (scenario 1: haemodialysis (HD), 73%; peritoneal dialysis (PD), 14%; kidney transplantation (TX), 13%) was compared with three different scenarios: an increased proportion of incident RRT patients on PD (scenario 2: HD, 47%; PD, 40%; TX, 13%); on TX (scenario 3: HD, 52%; PD, 14%; TX, 34%); on both PD and TX (Scenario 4: HD, 26%; PD, 40%; TX, 34%).

RESULTS

Over 5-year time horizon, HD was dominated by PD. At a willingness-to-pay (WTP) threshold of US$44 300, TX was cost-effective compared with PD with an incremental cost-effectiveness ratio of US$35 518 per quality-adjusted life year (QALY) gained. The scenario 2 held a dominant position over the scenario 1, with a net saving of US$ 5.92 million and an additional gain of 6.24 QALYs. The scenarios 3 and 4 were cost-effective compared with scenario 1 at a WTP threshold of US$44 300. The above results were consistent across the three time horizons.

CONCLUSIONS

TX is the most cost-effective RRT modality, followed in order by PD and HD. The strategy with an increased proportion of incident patients on PD and TX is cost-effective compared with the current practice pattern at the given WTP threshold. The planning for RRT service delivery should incorporate efforts to increase the utilisation of PD and TX in China.

Outcomes of end-stage renal disease patients in the PROCESS trial

OBJECTIVE

Intravenous fluid administration is a main component of sepsis therapy, but physicians are cautious about giving fluids to end-stage renal disease (ESRD) patients out of concern for causing volume overload. We compared the outcomes of septic shock patients with and without ESRD and evaluated the association between early intravenous fluid administration and outcomes.

METHODS

We analyzed patients enrolled in the Protocolized Care for Early Septic Shock (PROCESS) trial, which studied different resuscitation strategies for early septic shock. Stratifying for ESRD, we compared patient characteristics, course of care, and outcomes between ESRD and non-ESRD. Using multivariable logistic regression, we determined the association between 6-hour total fluid volume (> = 30 mL/kg vs < 30 mL/kg) from preenrollment and outcomes.

RESULTS

There were 84 ESRD and 1257 non-ESRD patients. ESRD patients had a higher median Charlson Comorbidity score (5 vs 2, P < .001), higher median acute physiology and chronic health evaluation (APACHE) II score (26.5 vs 20.0, P < .001), and lower 6-hour intravenous fluid administration (54.7 vs 68.3 mL/kg, P < .001). Ninety-day mortality (33.3% vs 29.3%, P = .43) and intubation rate (31.0% vs 33.4%, P = .64) did not differ between groups. Fewer ESRD received > = 30 mL/kg (66.6% vs 86.7% P < .001). For ESRD, receipt of > = 30 mL/kg intravenous fluid did not alter any outcome. For non-ESRD patients, receiving   ≥30 mL/kg of intravenous fluid was associated with increased 90-day mortality (adjusted odds ratio = 1.64; 95% confidence interval, 1.03-2.61).

CONCLUSIONS

In the PROCESS trial, ESRD patients had similar outcomes to non-ESRD patients. Although ESRD patients received less intravenous fluid administration, most received over 30 mL/kg in the first 6 hours. In contrast to non-ESRD patients, receiving  ≥30 mL/kg of intravenous fluid was not associated with worse outcomes in ESRD.

Impact of primary aldosteronism on renal function in patients with type 2 diabetes

AIMS/INTRODUCTION

Renal dysfunction might quickly progress in patients with type 2 diabetes mellitus, when accompanied by hypertension. However, whether primary aldosteronism (PA), which autonomously over-secretes aldosterone, causes additional renal damage in patients with type 2 diabetes mellitus is unclear. We evaluated the impact of PA on renal function in patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

A retrospective review of all patients with type 2 diabetes mellitus who visited Yokohama Rosai Hospital's (Yokohama Japan) outpatient department between April 2017 and March 2018 was carried out. Records of patients with PA who underwent PA treatment by adrenalectomy or mineralocorticoid receptor antagonists (PA group) and those without PA (non-PA group) were extracted, and renal function was compared between the two groups. Untreated PA patients were excluded, as their renal function might be overestimated as a result of glomerular hyperfiltration.

RESULTS

There were 83 patients in the PA group and 1,580 patients in the non-PA group. The PA group had significantly lower estimated glomerular filtration rates than the non-PA group (66.3 [52.4-78.2] vs 70.5 [56.0-85.6] mL/min/1.73 m2 , P = 0.047). Multiple regression analysis showed that PA was a factor for decreased estimated glomerular filtration rate, independent of age, sex, glycated hemoglobin, diuretic use and hypertension (P = 0.025). PA induced a 3.7-mL/min/1.73 m2 (95% confidence interval 0.47-6.9) decrease in estimated glomerular filtration rate, equivalent to that induced by 4.4 years of aging.

CONCLUSIONS

Our results show that in patients with type 2 diabetes mellitus, PA is an independent risk factor for renal dysfunction. To prevent the progression of renal failure, PA should not be overlooked.

Use of sodium-glucose co-transporter-2 inhibitors in Asian patients with type 2 diabetes and kidney disease: An Asian perspective and expert recommendations

Early onset of type 2 diabetes and a high prevalence of co-morbidities predispose the Asian population to a high risk for, and rapid progression of, diabetic kidney disease (DKD). Apart from renin-angiotensin system inhibitors, sodium-glucose co-transporter-2 (SGLT-2) inhibitors have been shown to delay renal disease progression in patients with DKD. In this review article, we consolidate the existing literature on SGLT-2 inhibitor use in Asian patients with DKD to establish contemporary guidance for clinicians. We extensively reviewed recommendations from international and regional guidelines, data from studies on Asian patients with DKD, global trials (DAPA-CKD, CREDENCE and DELIGHT) and cardiovascular outcomes trials. In patients with DKD, SGLT-2 inhibitor therapy significantly reduced albuminuria and the risk of hard renal outcomes (defined as the onset of end-stage kidney disease, substantial decline in renal function from baseline and renal death), cardiovascular outcomes and hospitalization for heart failure. In all the cardiovascular and renal outcomes trials, there was an initial decline in the estimated glomerular filtration rate (eGFR), which was followed by a slowing in the decline of renal function compared with that seen with placebo. Despite an attenuation in glucose-lowering efficacy in patients with low eGFR, there were sustained reductions in body weight and blood pressure, and an increase in haematocrit. Based on the available evidence, we conclude that SGLT-2 inhibitors represent an evidence-based therapeutic option for delaying the progression of renal disease in Asian patients with DKD and preserving renal function in patients at high risk of kidney disease.

Adherence to Healthy Dietary Patterns and Risk of CKD Progression and All-Cause Mortality: Findings From the CRIC (Chronic Renal Insufficiency Cohort) Study

RATIONALE & OBJECTIVE

Current dietary guidelines recommend that patients with chronic kidney disease (CKD) restrict individual nutrients, such as sodium, potassium, phosphorus, and protein. This approach can be difficult for patients to implement and ignores important nutrient interactions. Dietary patterns are an alternative method to intervene on diet. Our objective was to define the associations of 4 healthy dietary patterns with risk for CKD progression and all-cause mortality among people with CKD.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

2,403 participants aged 21 to 74 years with estimated glomerular filtration rates of 20 to 70mL/min/1.73m2 and dietary data in the Chronic Renal Insufficiency Cohort (CRIC) Study.

EXPOSURES

Healthy Eating Index-2015, Alternative Healthy Eating Index-2010, alternate Mediterranean diet (aMed), and Dietary Approaches to Stop Hypertension (DASH) diet scores were calculated from food frequency questionnaires.

OUTCOMES

(1) CKD progression defined as≥50% estimated glomerular filtration rate decline, kidney transplantation, or dialysis and (2) all-cause mortality.

ANALYTICAL APPROACH

Cox proportional hazards regression models adjusted for demographic, lifestyle, and clinical covariates to estimate hazard ratios (HRs) and 95% CIs.

RESULTS

There were 855 cases of CKD progression and 773 deaths during a maximum of 14 years. Compared with participants with the lowest adherence, the most highly adherent tertile of Alternative Healthy Eating Index-2010, aMed, and DASH had lower adjusted risk for CKD progression, with the strongest results for aMed (HR, 0.75; 95% CI, 0.62-0.90). Compared with participants with the lowest adherence, the highest adherence tertiles for all scores had lower adjusted risk for all-cause mortality for each index (24%-31% lower risk).

LIMITATIONS

Self-reported dietary intake.

CONCLUSIONS

Greater adherence to several healthy dietary patterns is associated with lower risk for CKD progression and all-cause mortality among people with CKD. Guidance to adopt healthy dietary patterns can be considered as a strategy for managing CKD.

TWEAK-Fn14 as a common pathway in the heart and the kidneys in cardiorenal syndrome

There is a complex relationship between cardiac and renal disease, often referred to as the cardiorenal syndrome. Heart failure adversely affects kidney function, and both acute and chronic kidney disease are associated with structural and functional changes to the myocardium. The pathological mechanisms and contributing interactions that surround this relationship remain poorly understood, limiting the opportunities for therapeutic intervention. The cytokine tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor, fibroblast growth factor-inducible 14 (Fn14), are abundantly expressed in injured kidneys and heart. The TWEAK-Fn14 axis promotes responses that drive tissue injury such as inflammation, proliferation, fibrosis, and apoptosis, while restraining the expression of tissue protective factors such as the anti-aging factor Klotho and the master regulator of mitochondrial biogenesis peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). High levels of TWEAK induce cardiac remodeling, and promote inflammation, tubular and podocyte injury and death, fibroblast proliferation, and, ultimately, renal fibrosis. Accordingly, targeting the TWEAK-Fn14 axis is protective in experimental kidney and heart disease. TWEAK has also emerged as a biomarker of kidney damage and cardiovascular outcomes and has been successfully targeted in clinical trials. In this review, we update our current knowledge of the roles of the TWEAK-Fn14 axis in cardiovascular and kidney disease and its potential contribution to the cardiorenal syndrome. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Medullary Blood Oxygen Level-Dependent MRI Index (R2*) is Associated with Annual Loss of Kidney Function in Moderate CKD

BACKGROUND

The estimated glomerular filtration rate (eGFR) is frequently used to monitor progression of kidney disease. Multiple values have to be obtained, sometimes over years to determine the rate of decline in kidney function. Recent data suggest that functional MRI (fMRI) methods may be able to predict loss of eGFR. In a prior study, baseline data with multi-parametric MRI in individuals with diabetes and moderate CKD was reported. This report extends our prior observations in order to evaluate the temporal variability of the fMRI measurements over 36 months and their association with annual change in eGFR.

METHODS

Twenty-four subjects with moderate CKD completed 3 sets of MRI scans over a 36-month period. Blood oxygenation level-dependent (BOLD), arterial spin labeling perfusion, and diffusion MRI images were acquired using a 3 T scanner. Coefficients of variation was used to evaluate variability between subjects at each time point and temporal variability within each subject. We have conducted mixed effects models to examine the trajectory change in GFR over time using time and MRI variables as fixed effects and baseline intercept as random effect. Associations of MRI image markers with annual change in eGFR were evaluated.

RESULTS

Multi-parametric functional renal MRI techniques in individuals with moderate CKD showed higher temporal variability in R2* of medulla compared to healthy individuals. This was consistent with the significant lower R2* in medulla observed at 36 months compared to baseline values. The results of linear mixed model showing that R2*_Medulla was the only predictor associated with change in eGFR over time. Furthermore, a significant association of medullary R2* with annual loss of eGFR was observed at all the 3 time points.

CONCLUSIONS

The lower R2* values and the higher temporal variability in the renal medulla over time suggest the ability to monitor progressive CKD. These were confirmed by the fact that reduced medullary R2* was associated with higher annual loss in eGFR. These data collectively emphasize the need for inclusion of medulla in the analysis of renal BOLD MRI studies.

Cardiac arrhythmia during early-week and mid-week dialysis in hemodialysis patients

Data on cardiac arrhythmia and electrolyte changes during the dialysis cycle have been limited. Fifty-two hemodialysis (HD) patients underwent 48-h Holter monitoring during early-week and mid-week HD sessions. Pre-HD and post-HD blood samples were collected in both HD sessions. The 48-h Holter data were divided into five phases: (1) 4-h during the early-week HD (HD1), (2) 12-h post-HD1, (3) 16-h period between Phases 2 and 4 (used as the patient's baseline electrocardiography [ECG]), (4) 12-h pre-HD2 phase, and (5) 4-h during the mid-week HD (HD2). The patients' mean age was 68.54 ± 13.37 years. We found that the dialysate-to-serum[K] gradient and changes of S[K] were significantly higher in HD1 than in HD2, as well as changes of S[Mg]. There were no significant ECG changes during the 4-h HD1 and HD2 when compared with the baseline ECG. Phase 2 of Holter ECG was the most common phase that showed significant changes (increased QT interval dispersion (QTD), increased ventricular events, increased number of premature ventricular contractions, ST elevation and ST depression), which was contributed from the dialysate[K] 2 mmol/L subgroup, but not the dialysate[K] 3 mmol/L subgroup. In the subgroup of patients with a high ultrafiltration rate (UFR; mean UFR ≥10 mL/kg/h), there were significantly increased ventricular events and ST-segment changes in Phase 2. In conclusion, ECG changes were associated with the dialysis cycle, significantly in the 12-h after early-week HD sessions. These may be associated with low dialysate[K] or high dialysate-to-S[K] gradient, high ultrafiltration rate and duration of the interdialytic interval.

Slipping Through the Pores: Hypoalbuminemia and Albumin Loss During Hemodialysis

Hypoalbuminemia results when compensatory mechanisms are unable to keep pace with derangements in catabolism/loss and/or decreased synthesis of albumin. Across many disease states, including chronic kidney disease (CKD), hypoalbuminemia is a well-established, independent risk factor for adverse outcomes, including mortality. In the setting of CKD, reduced serum albumin concentrations are often a manifestation of protein-energy wasting, a state of metabolic and nutritional alterations resulting in reduced protein and energy stores. The progression of CKD to kidney failure and the initiation of maintenance hemodialysis (HD) further predisposes an already at-risk population toward hypoalbuminemia such that approximately 60% of HD patients have albumin concentrations <4.0 g/dl. Albumin loss into the dialysate through the dialyzer appears to be a potentially modifiable cause of hypoalbuminemia in some patients. A group of newer dialyzers for maintenance HD-sometimes termed protein-leaking or medium cut-off membranes-aim to improve clearance of middle molecules (vs high flux dialyzers) but are associated with increased albumin losses. In this article, we will examine the impact of dialyzer selection on albumin losses during conventional HD, including the clinical relevance of such losses on serum albumin levels. Data on the clinical relevance of albumin losses during dialysis and current gaps in the evidence base are also discussed.

Early Chronic Kidney Disease Care Programme delays kidney function deterioration in patients with stage I-IIIa chronic kidney disease: an observational cohort study in Taiwan

OBJECTIVES

To investigate the effect of the Early Chronic Kidney Disease (CKD) Care Programme on CKD progression in patients with CKD stage I-IIIa.

DESIGN

Observational cohort study.

SETTING

Taipei Medical University Research Database from three affiliated hospitals.

PARTICIPANTS

Adult non-pregnant patients with CKD stage I-IIIa from Taipei Medical University Research Database between 1 January 2012 and 31 August 2017 were recruited. These patients were divided into Early CKD Care Programme participants (case) and non-participants (control). The models were matched by age, sex, estimated glomerular filtration rate and CKD stage with 1:2 propensity score to reduce bias between two groups.

OUTCOME MEASURES

The risks of CKD stage I-IIIa progression to IIIb between Early CKD Care Programme participants and non-participants.

RESULTS

Compared with the control group, the case group demonstrated more comorbidities and higher proportions of hypertension, diabetes mellitus, gout, dyslipidaemia, heart disease and cerebrovascular disease, but had lower risk of progression to CKD stage IIIb before and (HR 0.72; 95% CI 0.61 to 0.85) and after (adjusted HR (aHR) 0.67; 95% CI 0.55 to 0.81) adjustments. Moreover, Kaplan-Meier analysis revealed the cumulative incidence of CKD stage IIIb was significantly lower in the case group than in the control group. Finally, the programme was an independent protective factor against progression to stage IIIb, especially in patients with CKD stage IIIa before (HR 0.72; 95% CI 0.61 to 0.85) and after (aHR 0.67; 95% CI 0.55 to 0.81) adjustments.

CONCLUSIONS

The Early CKD Care Programme is an independent protective factor against progression of early CKD.

Nutrition-Based Management of Inflammaging in CKD and Renal Replacement Therapies

Access to renal transplantation guarantees a substantial improvement in the clinical condition and quality of life (QoL) for end-stage renal disease (ESRD) patients. In recent years, a greater number of older patients starting renal replacement therapies (RRT) have shown the long-term impact of conservative therapies for advanced CKD and the consequences of the uremic milieu, with a frail clinical condition that impacts not only their survival but also limits their access to transplantation. This process, referred to as “inflammaging,” might be reversible with a tailored approach, such as RRT accompanied by specific nutritional support. In this review, we summarize the evidence demonstrating the presence of several proinflammatory substances in the Western diet (WD) and the positive effect of unprocessed food consumption and increased fruit and vegetable intake, suggesting a new approach to reduce inflammaging with the improvement of ESRD clinical status. We conclude that the Mediterranean diet (MD), because of its modulative effects on microbiota and its anti-inflammaging properties, may be a cornerstone in a more precise nutritional support for patients on the waiting list for kidney transplantation.

COVID-19 Among US Dialysis Patients: Risk Factors and Outcomes From a National Dialysis Provider

Rationale & Objective

During the coronavirus disease 2019 (COVID-19) pandemic, patients receiving maintenance dialysis are a highly vulnerable population due to their comorbidities and circumstances that limit physical distancing during treatment. This study sought to characterize the risk factors for and outcomes following COVID-19 in this population.

Study Design

Retrospective cohort study.

Setting & Participants

Maintenance dialysis patients in clinics of a midsize national dialysis provider that had at least 1 patient who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from February to June 2020.

Predictors

Demographics, dialysis characteristics, residence in a congregated setting, comorbid conditions, measurements of frailty, and use of selected medications.

Outcomes

COVID-19, defined as having a positive SARS-CoV-2 test result, and all-cause mortality among those with COVID-19.

Analytical Approach

Logistic regression analyses conducted to identify clinical characteristics associated with COVID-19 and risk factors associated with mortality among patients following COVID-19.

Results

438 of 7948 (5.5%) maintenance dialysis patients developed COVID-19. Male sex, Black race, in-center dialysis (vs home dialysis), treatment at an urban clinic, residence in a congregate setting, and greater comorbidity were associated with contracting COVID-19. Odds of COVID-19 were 17-fold higher for those residing in a congregated setting (odds ratio [OR], 17.10 [95% CI, 13.51-21.54]). Of the 438 maintenance dialysis patients with COVID-19, 109 (24.9%) died. Older age, heart disease, and markers of frailty were associated with mortality.

Limitations

No distinction was detected between symptomatic and asymptomatic SARS-CoV-2 positivity, with asymptomatic screening limited by testing capacity during this initial COVID-19 surge period.

Conclusions

COVID-19 is common among patients receiving maintenance dialysis, particularly those residing in congregate settings. Among maintenance dialysis patients with COVID-19, mortality is high, exceeding 20%.

Predialysis Potassium Variability and Postdialysis Mortality in Patients With Advanced CKD

Introduction

Patients with advanced non–dialysis-dependent chronic kidney disease (NDD-CKD) are prone to potassium (K) imbalances due to reduced kidney function. Both hypo- and hyperkalemia are associated with increased mortality; however, it is unclear if K variability before dialysis initiation is associated with outcomes after dialysis initiation.

Methods

We identified 34,167 US veterans with advanced NDD-CKD transitioning to dialysis between October 1, 2007, through March 31, 2015, who had at least 1 K measurement each year over a 3-year period before transition (3-year prelude). For each patient, a linear mixed-effects model was used to regress K over time (in years) over the 3-year prelude to derive K variability (square root of the average squared distance between the observed and estimated K). The main outcomes of interest were 6-month all-cause and cardiovascular mortality after dialysis initiation. Multivariable Cox and Fine-Gray competing risk regression adjusted for 3-year prelude K intercept, K slope (per year), demographics, smoking status, comorbidities, length of hospitalizations, body mass index, vascular access type, medications, average estimated glomerular filtration rate, and number of K measurements over the 3-year prelude were used to assess the association of K variability (expressed as quartiles) with all-cause and cardiovascular mortality, respectively.

Results

Higher prelude K variability was associated with higher multivariable-adjusted risk of all-cause mortality but not cardiovascular mortality (adjusted hazard/subhazard ratios [95% confidence interval] for highest quartile [vs. lowest] of K variability, 1.14 [1.03–1.25] and 0.99 [0.85–1.16] for all-cause and cardiovascular mortality, respectively).

Conclusion

Higher K variability is associated with higher all-cause mortality after dialysis initiation.

Impact of cardiovascular risk stratification strategies in kidney transplantation over time

BACKGROUND

Kidney transplant recipients exhibit a dramatically increased cardiovascular (CV) risk. In 2007, Austrian centres implemented a consensus of comprehensive CV screening programme prior to kidney transplantation (KT). The consensus placed a particular emphasis on screening for coronary artery disease (CAD) with cardiac computed tomography (CT) or coronary angiography (CAG) in patients with diabetes mellitus, known CAD or those having multiple conventional CV risk factors. Here, we investigate if this affected risk stratification and post-transplant CV outcomes.

METHODS

In a retrospective chart review, we evaluated 551 KTs performed from 2003 to 2015 in our centre. Patients were categorized into three groups: KT before (2003-07), directly after (2008-11) and 5 years after (2012-15) implementation of the consensus. We analysed clinical characteristics, the rate of cardiac CTs and CAGs prior to KT as well as major adverse cardiac events (MACEs) during a 2-year follow-up after KT.

RESULTS

The three study groups showed a homogeneous distribution of comorbidities and age. Significantly more cardiac CTs (13.6% versus 10.2% versus 44.8%; P = 0.002) and CAGs (39.6% versus 43.9% versus 56.2%; P = 0.003) were performed after the consensus. Coronary interventions were performed during 42 out of 260 CAGs (16.2%), the cumulative 2-year MACE incidence was 8.7%. Regarding MACE occurrence, no significant difference between the three groups was found.

CONCLUSION

CV risk stratification has become more rigorous and invasive after the implementation of the consensus; however, this was not associated with an improvement in CV outcome.

Indoxyl Sulfate Mediates the Low Inducibility of the NLRP3 Inflammasome in Hemodialysis Patients

The NLRP3 inflammasome is responsible for the maturation of caspase-1 and interleukin-1β (IL-1β). Despite the study about basal activity of the NLRP3 inflammasome in hemodialysis (HD) patients, little is known about its inducibility in the milieu of uremia. Peripheral blood mononuclear cells (PBMCs) isolated from 11 HD patients and 14 volunteers without a history of chronic kidney disease, as well as macrophages with or without the uremic toxin indoxyl sulfate (IS) pretreatment, underwent canonical NLRP3 inflammasome induction. Despite the high plasma levels of IL-1β in HD patients, caspase-1 and IL-1β in the PBMCs of HD patients remained predominantly immature and were not secreted in response to the canonical stimulus. In addition, while IS alone facilitated the inflammasome-independent secretion of IL-1β from macrophages, IS exposure before induction reduced the inducibility of the NLRP3 inflammasome, characterized by insufficient maturation of caspase-1. The low expression of inflammasome components, which was observed in both IS-pretreated cells and the PBMCs of HD patients, was probably responsible for the low inducibility.

Prevalence, risk factors and impact on outcomes of 30-day unexpected rehospitalization in incident peritoneal dialysis patients

Background

Rehospitalization is a major problem for end stage renal disease (ESRD) populations. However, researches on 30-day unexpected rehospitalzation of incident peritoneal dialysis (PD) patients were limited. This study aimed to investigate the prevalence, risk factors and impact on outcomes of 30-day unexpected rehospitalization in incident PD patients.

Methods

This was a retrospective cohort study. Patients who accepted PD catheter implantation in our centre from Jan 1, 2006 to Dec 31, 2013 and regular follow-up were included. The demographic characteristics, laboratory parameters, and rehospitalization data were collected and analyzed. The primary outcome was all-cause mortality, and the secondary outcomes included cardiovascular disease (CVD) mortality and technical failure.

Results

Totally 1632 patients (46.9 ± 15.3 years old, 60.1% male, 25.6% with diabetes) were included. Among them, 149 (9.1%) had a 30-day unexpected rehospitalization after discharge. PD-related peritonitis (n = 48, 32.2%), catheter malfunction (n = 30, 20.1%) and severe fluid overload (n = 19, 12.8%) were the top three causes for the rehospitalization. Multivariate logistic regression analysis showed that length of index hospital stays [Odds ratio (OR) =1.02, 95% confidence interval (CI) 1.00–1.03, P = 0.036) and hyponatremia (OR = 1.85, 95% CI 1.06–3.24, P = 0.031) were independently associated with the rehospitalization. Multivariate Cox regression analysis indicated that 30-day rehospitalization was an independent risk factor for all-cause mortality [Hazard ratio (HR) =1.52, 95% CI 1.07–2.16, P = 0.019) and CVD mortality (HR = 1.73, 95% CI 1.03–2.90, P = 0.038).

Conclusions

The prevalence of 30-day unexpected rehospitalization for incident PD patients in our centre was 9.1%. The top three causes for the rehospitalization were PD-related peritonitis, catheter malfunction and severe fluid overload. Thirty-day unexpected rehospitalization increased the risk of all-cause mortality and CVD mortality for PD patients.

Incidence and Clinical Impacts of COVID-19 Infection in Patients with Hemodialysis: Systematic Review and Meta-Analysis of 396,062 Hemodialysis Patients

Hemodialysis (HD) patients are highly susceptible to COVID-19 infection. However, comprehensive assessments of current evidence regarding COVID-19 in HD patients remain incomplete. We systematically searched PUBMED and EMBASE for articles published on incidence or mortality of COVID-19 infection in HD patients until September 2020. Two independent researchers extracted data and study-level risk of bias across studies. We conducted meta-analysis of proportions for incidence and mortality rate. Study heterogeneity and publication bias were assessed. A total of 29 articles with 3261 confirmed COVID-19 cases from a pool of 396,062 HD patients were identified. Incidence of COVID-19 in these HD patients was 7.7% (95% CI: 5.0-10.9%; study heterogeneity: I2 = 99.7%, p < 0.001; risk of publication bias, Egger's test, p < 0.001). Overall mortality rate was 22.4% (95% CI: 17.9-27.1%; study heterogeneity: I2 = 87.1%, p < 0.001; risk of publication bias, Egger's test: p = 0.197) in HD patients with COVID-19. Reported estimates were higher in non-Asian than Asian countries. Quality of study may affect the reported incidence but not the mortality among studies. Both incidence and mortality of COVID-19 infection were higher in HD patients. Available data may underestimate the real incidence of infection. International collaboration and standardized reporting of epidemiological data should be needed for further studies.

A review of indications and comorbidities in which warfarin may be the preferred oral anticoagulant

WHAT IS KNOWN AND OBJECTIVE

Direct oral anticoagulants (DOACs) are increasingly prescribed instead of warfarin for chronic anticoagulation for ease of dosing, fewer interactions, and less stringent monitoring. However, it is important to consider indications and comorbidities for which warfarin is still the preferred anticoagulant. This review aims to capture these clinical scenarios in which warfarin may still be preferred over DOACs.

METHODS

We undertook a comprehensive literature search using the PubMed database. Key search terms were based on DOAC clinical trial exclusion criteria, as well as indications and conditions in which the use of DOACs for anticoagulation has suggested harm. Society guidelines and tertiary literature were used to inform expert opinion where necessary. Studies were included if they investigated the use of DOACs or warfarin in the identified indications or conditions.

RESULTS AND DISCUSSION

Currently, evidence for the use of warfarin over DOACs for anticoagulation is strongest for patients with prosthetic valves, antiphospholipid syndrome, or a high risk of gastrointestinal bleeding. For several clinical situations, including mitral stenosis, obesity, altered gastrointestinal anatomy, pulmonary arterial hypertension, renal or hepatic impairment, and left ventricular thrombus, evidence is lacking but may eventually support the use of DOACs. Depending on indication and condition, appropriateness of DOAC use may vary by agent.

WHAT IS NEW AND CONCLUSION

New evidence continues to support new indications and conditions in which DOACs may be appropriate to use for anticoagulation. There are key clinical scenarios, however, in which emerging literature continues to support warfarin as the preferred anticoagulant.

The quest for cardiovascular disease risk prediction models in patients with nondialysis chronic kidney disease

PURPOSE OF REVIEW

Cardiovascular disease (CVD) is the leading cause of death in patients with chronic kidney disease (CKD). However, traditional CVD risk prediction equations do not work well in patients with CKD, and inclusion of kidney disease metrics such as albuminuria and estimated glomerular filtration rate have a modest to no benefit in improving prediction.

RECENT FINDINGS

As CKD progresses, the strength of traditional CVD risk factors in predicting clinical outcomes weakens. A pooled cohort equation used for CVD risk prediction is a useful tool for guiding clinicians on management of patients with CVD risk, but these equations do not calibrate well in patients with CKD, although a number of studies have developed modifications of the traditional equations to improve risk prediction. The reason for the poor calibration may be related to the fact that as CKD progresses, associations of traditional risk factors such as BMI, lipids and blood pressure with CVD outcomes are attenuated or reverse, and other risk factors may become more important.

SUMMARY

Large national cohorts such as the US Veteran cohort with many patients with evolving CKD may be useful resources for the developing CVD prediction models; however, additional considerations are needed for the unique composition of patients receiving care in these healthcare systems, including those with multiple comorbidities, as well as mental health issues, homelessness, posttraumatic stress disorders, frailty, malnutrition and polypharmacy. Machine learning over conventional risk prediction models may be better suited to handle the complexity needed for these CVD prediction models.

Efficacy and Safety of Tripterygium Glycoside in the Treatment of Diabetic Nephropathy: A Systematic Review and Meta-Analysis Based on the Duration of Medication

AIM

The aim of this study was to assess the clinical efficacy and safety of Tripterygium-derived glycosides (TG) after 3-month and 6-month of treatments of diabetic nephropathy (DN) and to resolve the conflict between medicine guidance and clinical practice for TG application.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials involving TG application in treating DN. We extensively searched PubMed, Cochrane Library, CNKI, VIP, Wan-Fang, CBM, Chinese Clinical Trial Registry, and WHO International Clinical Trial Registration Platform till November 2020, along with grey literature for diabetes and all other relevant publications to gather eligible studies. Based on the preset inclusion and exclusion criteria, document screening, quality assessment of methodology, and data extraction was conducted by two researchers independently. The methodological quality was assessed by the Cochrane risk test from the Cochrane Handbook 5.2, and then analyses were performed by Review Manager 5.3 (Rev Man 5.3). The quality of output evidence was classified by GRADE.

RESULTS

Thirty-one eligible studies (2764 patients) were included for this meta-analysis. Our study results showed a comparable significant decrease in the 24 h-UTP and blood creatinine levels in DN patients from both 3-month and 6-month TG treatment groups, compared with the routine symptomatic treatment alone. To the contrary of the findings from the included studies, our results showed that the occurrence of serious adverse reaction events was significantly higher in the TG treated group with 6 months of treatment duration compared to that of 3 months of the treatment course. However, the total AR ratio was slightly varied while increasing the percent of severe adverse events. GRADE assessment indicated that the quality of evidence investigating TG-induced adverse reactions was moderate and that for 24 h-UTP and blood creatinine indicators were considerably low.

CONCLUSION

Combinatorial treatment regimen including TG can significantly decrease the pathological indicators for DN progression, while it can also simultaneously predispose the patient to a higher risk for developing severe adverse events, as the medicine guidance indicates. Notably, even in 3-month of course duration smaller percent of severe adverse events can get to a fatal high percent and is likely to increase proportionally as the TG treatment continues. This suggests that TG-mediated DN treatment duration should be optimized to even less than 3 continuous months to avoid adverse event onset-associated further medical complications in DN patients. In clinical practice, serious attention should be paid to these severe side-effects even in a course normally considered safe, and importantly more high-quality studies are urgently warranted to obtain detailed insights into the balance between the efficacy and safety profiles of TG application in treating DN.