Improving the prognosis of patients with severely decreased glomerular filtration rate (CKD G4+): conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Characteristics of patients with undiagnosed stage 3 chronic kidney disease: results from an observational study (REVEAL-CKD) in China

Background

Early diagnosis of chronic kidney disease (CKD) is crucial for timely intervention to delay disease progression and improve patient outcomes. However, data for clinical characteristics of Chinese patients with undiagnosed, early-stage CKD are lacking.

Methods

REVEAL-CKD is a multinational, observational study using real-world data in selected countries to describe factors associated with undiagnosed stage 3 CKD, time to diagnosis, and CKD management post diagnosis. We analysed patient data from 20 hospitals in the China Renal Data System. Adult patients with two consecutive estimated glomerular filtration rate (eGFR) measurements indicating stage 3 CKD (30-<60 ml/min/1.73 m2) recorded >90-730 days apart from 2015 to 2020 were eligible.

Findings

Among 35,222 eligible patients, 25,214 (71.6%) were undiagnosed (lacked a CKD diagnostic code before and up to six months post-second-qualifying-eGFR). Only 2344 (9.3%) undiagnosed patients eventually received a delayed diagnosis, whose median time to diagnosis was 18.1 (95% CI: 17.6-18.8) months. Age ≥65 years, being female, stage 3A CKD, and the absence of nephrology visit and comorbidities (diabetes, established cardiovascular disease, heart failure, hypertension, or chronic nephritic syndrome) were associated with undiagnosed CKD (P < 0.001). Among the diagnosed patients, the proportion receiving ≥1 prescription of guideline-recommended medications (e.g. renin-angiotensin system inhibitors) increased and their eGFR decline attenuated post-diagnosis.

Interpretation

The high proportion of undiagnosed, early-stage CKD, and delayed diagnosis are concerning. The improved prescription patterns and the attenuation of eGFR decline post-diagnosis demonstrate the importance of early diagnosis and timely intervention in CKD patients.

Funding

AstraZeneca China.

Ultrasound viscoelastic imaging in the noninvasive quantitative assessment of chronic kidney disease

BACKGROUND

This study aims to evaluate the clinical application value of ultrasound viscoelastic imaging in noninvasive quantitative assessment of chronic kidney disease (CKD).

METHODS

A total of 332 patients with CKD and 190 healthy adults as a control group were prospectively enrolled. Before kidney biopsy, ultrasound viscoelastic imaging was performed to measure the mean stiffness value (Emean), mean viscosity coefficient (Vmean), and mean dispersion coefficient (Dmean) of the renal. CKD patients were divided into three groups based on estimated glomerular filtration rate. The differences in clinic, pathology, ultrasound image parameters between the control and patient groups, or among different CKD groups were compared. The correlation between viscoelastic parameters and pathology were analyzed.

RESULTS

Emean, Vmean, and Dmean in the control group were less than the CKD group (p < 0.05). In the identification of CKD from control groups, the area under curve of Vmean, Dmean, Emean, and combining the three parameters is 0.90, 0.79, 0.69, 0.91, respectively. Dmean and Vmean were increased with the decline of renal function (p < 0.05). Vmean and Dmean were positively correlated with white blood cell, urea, serum creatinine, and uric acid (p < 0.05). Vmean is positively correlated with interstitial fibrosis and inflammatory cell infiltration grades (p < 0.001).

CONCLUSIONS

Ultrasound viscoelastic imaging has advantages in noninvasive quantitative identification and evaluating renal function of CKD. Emean > 6.61 kPa, Vmean > 1.86 Pa·s, or Dmean > 7.51 m/s/kHz may suggest renal dysfunction. Combining Vmean, Dmean, and Emean can improve the efficiency of identifying CKD.

Spectrochip-based Calibration Curve Modeling (CCM) for Rapid and Accurate Multiple Analytes Quantification in Urinalysis

Most urine test strips are intended to enable the general population to rapidly and easily diagnose potential renal disorders. It is semi-quantitative in nature, and although the procedure is straightforward, certain factors will affect the judgmental outcomes. This study describes rapid and accurate quantification of twelve urine test strip parameters: leukocytes, nitrite, urobilinogen, protein, pH, occult blood, specific gravity, ketone, bilirubin, glucose, microalbumin, and creatinine using a micro-electromechanical system (MEMS)-based spectrophotometer, known as a spectrochip. For each parameter, absorption spectra were measured three times independently at eight different concentration levels of diluted standard solutions, and the average spectral intensities were calculated to establish the calibration curve under the characteristic wavelength (λ c ). Then, regression analysis on the calibration curve was performed with GraphPad Prism software, which revealed that the coefficient of determination (R 2 ) of the modeled calibration curves was greater than 0.95. This result illustrates that the measurements exceed standard levels, confirming the importance of a spectrochip for routine multi-parameter urine analysis. Thus, it is possible to obtain the spectral signal strength for each parameter at its characteristic wavelength in order to compare directly with the calibration curves in the future, even in situations when sample concentration is unknown. Additionally, the use of large testing machines can be reduced in terms of cost, time, and space by adopting a micro urine testing platform based on spectrochip, which also improves operational convenience and effectively enables point-of-care (POC) testing in urinalysis.

Effects of sodium-glucose co-transporter 2 inhibitors on heart failure events in chronic kidney disease: a systematic review and meta-analysis

AIMS

Sodium-glucose co-transporter 2 (SGLT-2) inhibitors significantly reduce the risk for hospitalizations for heart failure (HF) in patients with diabetes, and HF; findings in patients with chronic kidney disease (CKD) are not uniform. We aimed to perform a meta-analysis exploring the effect of SGLT-2 inhibitors on HF events in patients with CKD and across subgroups defined by baseline kidney function.

METHODS AND RESULTS

A systematic search in major electronic databases was performed. Randomized controlled trials (RCTs) providing data on the effect of SGLT-2 inhibitors on the primary outcome, time to hospitalization or urgent visit for worsening HF in patients with prevalent CKD at baseline or across subgroups stratified by baseline estimated glomerular-filtration-rate (eGFR) were included. Twelve studies (n = 89,191 participants) were included in the meta-analysis. In patients with CKD, treatment with SGLT-2 inhibitors reduced the risk for HF events by 32% compared to placebo [hazard ratio (HR) 0.68; 95% confidence interval (CI) 0.63-0.73]. Reduction in HF events with SGLT-2 inhibitors was more prominent in patients with eGFR <60 ml/min/1.73 m2 (HR 0.68; 95% CI 0.62-0.74) than in those with eGFR ≥60 ml/min/1.73 m2 (HR 0.76; 95% CI 0.69-0.83). Subgroup analysis according to type of SGLT-2 inhibitor showed a consistent treatment effect across all studied agents (p-subgroup-analysis = 0.44). Sensitivity analysis including data from studies including only diabetic patients showed an even more pronounced effect in eGFR subgroup <60 ml/min/1.73 m2 (HR 0.62; 95% CI 0.54-0.70).

CONCLUSION

Treatment with SGLT-2 inhibitors led to a significant reduction in HF events in patients with CKD. Such findings may change the landscape of prevention of HF events in patients with advanced CKD. PROSPERO Registration number CRD42022382857.

Association between gut microbiota and diabetic nephropathy: a two-sample Mendelian randomization study

Background

To clarify the causal relationship between gut microbiota and diabetic nephropathy (DN), we employed Mendelian randomization (MR). Despite a strong correlation observed, establishing causality is still unclear. By utilizing MR, we aimed to investigate this relationship further and shed light on the potential causal effect of gut microbiota on DN.

Methods

Genetic instrumental variables for gut microbiota were obtained from a GWAS with 18340 participants. DN summary statistics (1032 cases, 451248 controls) were sourced from a separate GWAS. The primary analysis used the inverse-variance weighted (IVW) method. Reverse MR analysis was conducted to explore reverse causation. Rigorous sensitivity analyses were performed to ensure the resilience and reliability of the study's findings.

Results

We found two bacterial traits associated with an increased risk of DN: genus LachnospiraceaeUCG008 (OR: 1.4210; 95% CI: 1.0450, 1.9322; p = 0.0250) and genus Terrisporobacter (OR: 1.9716; 95% CI: 1.2040, 3.2285; p = 0.0070). Additionally, phylum Proteobacteria (OR: 0.4394; 95% CI: 0.2721, 0.7096; p = 0.0008) and genus Dialister (OR: 0.4841; 95% CI: 0.3171, 0.7390; p = 0.0008) were protective against DN. Sensitivity analyses consistently supported these results. In the reverse MR analysis, no statistically significant associations were observed between DN and these four bacterial traits.

Conclusions

Our analyses confirmed a potential causal relationship between certain gut microbiota taxa and the risk of DN. However, additional studies are required to elucidate the underlying mechanisms through which gut microbiota influences the development of DN.

Associations of Urine and Plasma Metabolites With Kidney Failure and Death in a Chronic Kidney Disease Cohort

RATIONALE & OBJECTIVE

Biomarkers that enable better identification of persons with chronic kidney disease (CKD) who are at higher risk for disease progression and adverse events are needed. This study sought to identify urine and plasma metabolites associated with progression of kidney disease.

STUDY DESIGN

Prospective metabolome-wide association study.

SETTING & PARTICIPANTS

Persons with CKD enrolled in the GCKD (German CKD) study with metabolite measurements, with external validation within the ARIC (Atherosclerosis Risk in Communities) Study.

EXPOSURES

1,513 urine and 1,416 plasma metabolites (Metabolon Inc) measured at study entry using untargeted mass spectrometry.

OUTCOMES

Main end points were kidney failure (KF) and a composite kidney end point (CKE) of KF, estimated glomerular filtration rate<15mL/min/1.73m2, or a 40% decrease in estimated glomerular filtration rate. Death from any cause was a secondary end point. After a median of 6.5 years of follow-up, 500 persons had experienced KF, 1,083 had experienced the CKE, and 680 had died.

ANALYTICAL APPROACH

Time-to-event analyses using multivariable proportional hazard regression models in a discovery-replication design with external validation.

RESULTS

5,088 GCKD study participants were included in analyses of urine metabolites, and 5,144 were included in analyses of plasma metabolites. Among 182 unique metabolites, 30 were significantly associated with KF, 49 with the CKE, and 163 with death. The strongest association with KF was observed for plasma hydroxyasparagine (HR, 1.95; 95% CI, 1.68-2.25). An unnamed metabolite measured in plasma and urine was significantly associated with KF, the CKE, and death. External validation of the identified associations of metabolites with KF or the CKE revealed directional consistency for 88% of observed associations. Selected associations of 18 metabolites with study outcomes have not been previously reported.

LIMITATIONS

Use of observational data and semiquantitative metabolite measurements at a single time point.

CONCLUSIONS

The observed associations between metabolites and KF, the CKE, or death in persons with CKD confirmed previously reported findings and also revealed several associations not previously described. These findings warrant confirmatory research in other study cohorts.

PLAIN-LANGUAGE SUMMARY

Incomplete understanding of the variability of chronic kidney disease (CKD) progression motivated the search for new biomarkers that would help identify people at increased risk. We explored metabolites in plasma and urine for their association with unfavorable kidney outcomes or death in persons with CKD. Metabolomic analyses revealed 182 metabolites significantly associated with CKD progression or death. Many of these associations confirmed previously reported findings or were validated by analysis in an external study population. Our comprehensive screen of the metabolome serves as a valuable foundation for future investigations into biomarkers associated with CKD progression.

Effectiveness of DialBetesPlus, a self-management support system for diabetic kidney disease: Randomized controlled trial

We evaluated the effectiveness of a mobile health (mHealth) intervention for diabetic kidney disease patients by conducting a 12-month randomized controlled trial among 126 type 2 diabetes mellitus patients with moderately increased albuminuria (urinary albumin-to-creatinine ratio (UACR): 30-299 mg/g creatinine) recruited from eight clinical sites in Japan. Using a Theory of Planned Behavior (TPB) behavior change theory framework, the intervention provides patients detailed information in order to improve patient control over exercise and dietary behaviors. In addition to standard care, the intervention group received DialBetesPlus, a self-management support system allowing patients to monitor exercise, blood glucose, diet, blood pressure, and body weight via a smartphone application. The primary outcome, change in UACR after 12 months (used as a surrogate measure of renal function), was 28.8% better than the control group's change (P = 0.029). Secondary outcomes also improved in the intervention group, including a 0.32-point better change in HbA1c percentage (P = 0.041). These improvements persisted when models were adjusted to account for the impacts of coadministration of drugs targeting albuminuria (GLP-1 receptor agonists, SGLT-2 inhibitors, ACE inhibitors, and ARBs) (UACR: -32.3% [95% CI: -49.2%, -9.8%] between-group difference in change, P = 0.008). Exploratory multivariate regression analysis suggests that the improvements were primarily due to levels of exercise. This is the first trial to show that a lifestyle intervention via mHealth achieved a clinically-significant improvement in moderately increased albuminuria.

Prognostic Models in Nephrology: Where Do We Stand and Where Do We Go from Here? Mapping Out the Evidence in a Scoping Review

Prognostic models can strongly support individualized care provision and well-informed shared decision making. There has been an upsurge of prognostic research in the field of nephrology, but the uptake of prognostic models in clinical practice remains limited. Therefore, we map out the research field of prognostic models for kidney patients and provide directions on how to proceed from here. We performed a scoping review of studies developing, validating, or updating a prognostic model for patients with CKD. We searched all published models in PubMed and Embase and report predicted outcomes, methodological quality, and validation and/or updating efforts. We found 602 studies, of which 30.1% concerned CKD populations, 31.6% dialysis populations, and 38.4% kidney transplantation populations. The most frequently predicted outcomes were mortality ( n =129), kidney disease progression ( n =75), and kidney graft survival ( n =54). Most studies provided discrimination measures (80.4%), but much less showed calibration results (43.4%). Of the 415 development studies, 28.0% did not perform any validation and 57.6% performed only internal validation. Moreover, only 111 models (26.7%) were externally validated either in the development study itself or in an independent external validation study. Finally, in 45.8% of development studies no useable version of the model was reported. To conclude, many prognostic models have been developed for patients with CKD, mainly for outcomes related to kidney disease progression and patient/graft survival. To bridge the gap between prediction research and kidney patient care, patient-reported outcomes, methodological rigor, complete reporting of prognostic models, external validation, updating, and impact assessment urgently need more attention.

Multicentre external validation of the prognostic model kidney failure risk equation in patients with CKD stages 3 and 4 in Peru: a retrospective cohort study

OBJECTIVES

To externally validate the four-variable kidney failure risk equation (KFRE) in the Peruvian population for predicting kidney failure at 2 and 5 years.

DESIGN

A retrospective cohort study.

SETTING

17 primary care centres from the Health's Social Security of Peru.

PARTICIPANTS

Patients older than 18 years, diagnosed with chronic kidney disease stage 3a-3b-4 and 3b-4, between January 2013 and December 2017. Patients were followed until they developed kidney failure, died, were lost, or ended the study (31 December 2019), whichever came first.

PRIMARY AND SECONDARY OUTCOME MEASURES

Performance of the KFRE model was assessed based on discrimination and calibration measures considering the competing risk of death.

RESULTS

We included 7519 patients in stages 3a-4 and 2798 patients in stages 3b-4. The estimated cumulative incidence of kidney failure, accounting for competing event of death, at 2 years and 5 years, was 1.52% and 3.37% in stages 3a-4 and 3.15% and 6.86% in stages 3b-4. KFRE discrimination at 2 and 5 years was high, with time-dependent area under the curve and C-index >0.8 for all populations. Regarding calibration in-the-large, the observed to expected ratio and the calibration intercept indicated that KFRE underestimates the overall risk at 2 years and overestimates it at 5 years in all populations.

CONCLUSIONS

The four-variable KFRE models have good discrimination but poor calibration in the Peruvian population. The model underestimates the risk of kidney failure in the short term and overestimates it in the long term. Further research should focus on updating or recalibrating the KFRE model to better predict kidney failure in the Peruvian context before recommending its use in clinical practice.

Serum uric acid: a futile bystander in endothelial function?

PURPOSE

This study aims to investigate the relationship between serum uric acid levels and endothelial function, oxidative stress, and hemodynamic parameters, and to determine if uric acid levels provide additional insights beyond traditional factors like ageing and hypertension in volunteers with low cardiovascular risk factors. Serum uric acid is known for its antioxidant properties, but it may also contribute to cardiovascular risk.

MATERIALS AND METHODS

The study enrolled 40 male participants, divided into three groups based on age and blood pressure status. Group 1 comprised younger participants, group 2 included older individuals without hypertension, and group 3 consisted of older patients with hypertension. The study assessed endothelial function using laser Doppler imaging and measured acetylcholine- and sodium nitroprusside-induced hyperaemia. The heat microcirculatory response was also examined in the presence of L-NAME, an inhibitor of NOS synthase. The study evaluated oxidative stress and arterial stiffness by measuring allantoin, angiotensin II, Homocitrulline/Lysine, and Chloro-Tyrosine/Tyrosine ratios, as well as by performing non-invasive measurements of aortic augmentation indexes and carotid-femoral pulse wave velocity.

RESULTS

The study found that uric acid levels did not differ significantly among the three groups. Augmentation indexes increased with ageing, but hypertension did not have an additional effect. Blood pressure and carotid-femoral pulse wave velocity differed among the groups, with the lowest values among younger participants and the highest values among older individuals with hypertension. Allantoin and angiotensin II levels did not differ among the groups. However, Homocitrulline/Lysine and Chloro-Tyrosine/Tyrosine ratios were significantly lower in young subjects. Correlation and multivariable analysis showed that uric acid had no effect on any of the studied parameters. Despite a strong association between ageing and systolic blood pressure with impaired endothelial function, oxidative stress, and arterial stiffness, only ageing retained a significant effect in the multivariable analysis.

CONCLUSION

In healthy or hypertensive adults with normal renal function, serum uric acid appears to be a futile bystander in endothelial function, oxidative stress, and arterial stiffness, in contrast to ageing, which reduces NO bioavailability. This study suggests that traditional factors such as ageing and hypertension should be the focus of clinical assessment and management of cardiovascular risk, rather than uric acid levels.

Trends and perspectives for improving quality of chronic kidney disease care: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Chronic kidney disease (CKD) affects over 850 million people globally, and the need to prevent its development and progression is urgent. During the past decade, new perspectives have arisen related to the quality and precision of care for CKD, owing to the development of new tools and interventions for CKD diagnosis and management. New biomarkers, imaging methods, artificial intelligence techniques, and approaches to organizing and delivering healthcare may help clinicians recognize CKD, determine its etiology, assess the dominant mechanisms at given time points, and identify patients at high risk for progression or related events. As opportunities to apply the concepts of precision medicine for CKD identification and management continue to be developed, an ongoing discussion of the potential implications for care delivery is required. The 2022 KDIGO Controversies Conference on Improving CKD Quality of Care: Trends and Perspectives examined and discussed best practices for improving the precision of CKD diagnosis and prognosis, managing the complications of CKD, enhancing the safety of care, and maximizing patient quality of life. Existing tools and interventions currently available for the diagnosis and treatment of CKD were identified, with discussion of current barriers to their implementation and strategies for improving the quality of care delivered for CKD. Key knowledge gaps and areas for research were also identified.

CKD stage-specific utility of two equations for predicting 1-year risk of ESKD

BACKGROUND

The Kidney Failure Risk Equation (KFRE) and Kaiser Permanente Northwest (KPNW) models have been proposed to predict progression to ESKD among adults with CKD within 2 and 5 years. We evaluated the utility of these equations to predict the 1-year risk of ESKD in a contemporary, ethnically diverse CKD population.

METHODS

We conducted a retrospective cohort study of adult members of Kaiser Permanente Northern California (KPNC) with CKD Stages 3-5 from January 2008-September 2015. We ascertained the onset of ESKD through September 2016, and calculated stage-specific estimates of model discrimination and calibration for the KFRE and KPNW equations.

RESULTS

We identified 108,091 eligible adults with CKD (98,757 CKD Stage 3; 8,384 CKD Stage 4; and 950 CKD Stage 5 not yet receiving kidney replacement therapy), with mean age of 75 years, 55% women, and 37% being non-white. The overall 1-year risk of ESKD was 0.8% (95%CI: 0.8-0.9%). The KFRE displayed only moderate discrimination for CKD 3 and 5 (c = 0.76) but excellent discrimination for CKD 4 (c = 0.86), with good calibration for CKD 3-4 patients but suboptimal calibration for CKD 5. Calibration by CKD stage was similar to KFRE for the KPNW equation but displayed worse calibration across CKD stages for 1-year ESKD prediction.

CONCLUSIONS

In a large, ethnically diverse, community-based CKD 3-5 population, both the KFRE and KPNW equation were suboptimal in accurately predicting the 1-year risk of ESKD within CKD stage 3 and 5, but more accurate for stage 4. Our findings suggest these equations can be used in1-year prediction for CKD 4 patients, but also highlight the need for more personalized, stage-specific equations that predicted various short- and long-term adverse outcomes to better inform overall decision-making.

Decision aids to assist patients and professionals in choosing the right treatment for kidney failure

Background

Kidney services vary in the way they involve people with kidney failure (PwKF) in treatment decisions as management needs change. We discuss how decision-science applications support proactively PwKF to make informed decisions between treatment options with kidney professionals.

Methods

A conceptual review of findings about decision making and use of decision aids in kidney services, synthesized with reference to: the Making Informed Decisions-Individually and Together (MIND-IT) multiple stakeholder decision makers framework; and the Medical Research Council-Complex Intervention Development and Evaluation research framework.

Results

This schema represents the different types of decision aids that support PwKF and professional reasoning as they manage kidney disease individually and together; adjustments at micro, meso and macro levels supports integration in practice.

Conclusion

Innovating services to meet clinical guidelines on enhancing shared decision making processes means enabling all stakeholders to use decision aids to meet their goals within kidney pathways at individual, service and organizational levels.

Does Vitamin Supplementation Play a Role in Chronic Kidney Disease?

Although the role of vitamins in the human body is proven, guidelines for patients with chronic kidney disease (CKD) remain unclear. This narrative review summarizes the findings of 98 studies of CKD and the effects of vitamin D, B, C, A, E, and K supplementation on patients on dialysis for CKD, with the aim of summarizing the existing guidelines. The findings are promising, showing the potential effectiveness of vitamin supplementation with, for example, vitamins B, D, or C. However, recommendations are still ambiguous, especially in the case of vitamins A and K, due to the potential toxicity associated with higher doses for patients. Continued research is needed to rigorously evaluate the effectiveness and carefully consider the potential risks of some vitamin supplementation for patients with CKD.

Development and Validation of a Lifetime Risk Model for Kidney Failure and Treatment Benefit in Type 2 Diabetes: 10-Year and Lifetime Risk Prediction Models

BACKGROUND AND OBJECTIVES

Individuals with type 2 diabetes are at a higher risk of developing kidney failure. The objective of this study was to develop and validate a decision support tool for estimating 10-year and lifetime risks of kidney failure in individuals with type 2 diabetes as well as estimating individual treatment effects of preventive medication.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The prediction algorithm was developed in 707,077 individuals with prevalent and incident type 2 diabetes from the Swedish National Diabetes Register for 2002-2019. Two Cox proportional regression functions for kidney failure (first occurrence of kidney transplantation, long-term dialysis, or persistent eGFR <15 ml/min per 1.73 m2) and all-cause mortality as respective end points were developed using routinely available predictors. These functions were combined into life tables to calculate the predicted survival without kidney failure while using all-cause mortality as the competing outcome. The model was externally validated in 256,265 individuals with incident type 2 diabetes from the Scottish Care Information Diabetes database between 2004 and 2019.

RESULTS

During a median follow-up of 6.8 years (interquartile range, 3.2-10.6), 8004 (1%) individuals with type 2 diabetes in the Swedish National Diabetes Register cohort developed kidney failure, and 202,078 (29%) died. The model performed well, with c statistics for kidney failure of 0.89 (95% confidence interval, 0.88 to 0.90) for internal validation and 0.74 (95% confidence interval, 0.73 to 0.76) for external validation. Calibration plots showed good agreement in observed versus predicted 10-year risk of kidney failure for both internal and external validation.

CONCLUSIONS

This study derived and externally validated a prediction tool for estimating 10-year and lifetime risks of kidney failure as well as life years free of kidney failure gained with preventive treatment in individuals with type 2 diabetes using easily available clinical predictors.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2022_11_04_CJN05020422.mp3.

Chinese Clinical Practice Guideline for the Management of "CKD-PeriDialysis"-the Periods Prior to and in the Early-Stage of Initial Dialysis

The National Experts Group on Nephrology have developed these guidelines to improve the management of pre-dialysis and initial dialysis patients with chronic kidney disease (CKD) (two periods contiguous with dialysis initiation termed here 'PeriDialysis CKD'). The pre-dialysis period is variable, whereas the initial dialysis period is more fixed at 3 months to 6 months after initiating dialysis. The new concept and characteristics of 'CKD-PeriDialysis' are proposed in the guideline. During the CKD-PeriDialysis period, the incidence rate of complications, mortality and treatment cost significantly increases and the glomerular filtration rate (GFR) rapidly decreases, which requires intensive management. The guideline systematically and comprehensively elaborates the recommendations for indicators to be used in for disease evaluation, timing and mode selection of renal replacement therapy, dialysis adequacy evaluation, and diagnosis and treatment of common PeriDialysis complications. Finally, future research directions of CKD-PeriDialysis are proposed. CKD-PeriDialysis management is a difficult clinical issue in kidney disease, and the development and implementation of these guidelines is important to improve the management of CKD-PeriDialysis patients in China, which could ultimately improve survival rates and quality of life, and reduce the medical burden.

Barriers to conservative care from patients' and nephrologists' perspectives: the CKD-REIN study

BACKGROUND

Conservative care is increasingly considered an alternative to kidney replacement therapy for kidney failure management, mostly among the elderly. We investigated its status and the barriers to its implementation from patients' and providers' perspectives.

METHODS

We analysed data from 1204 patients with advanced chronic kidney disease (CKD) [estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2] enrolled at 40 nationally representative nephrology clinics (2013-16) who completed a self-administered questionnaire about the information they received and their preferred treatment option, including conservative care, if their kidneys failed. Nephrologists (n = 137) also reported data about their clinics' resources and practices regarding conservative care.

RESULTS

All participating facilities reported they were routinely able to offer conservative care, but only 37% had written protocols and only 5% had a person or team primarily responsible for it. Overall, 6% of patients were estimated to use conservative care. Among nephrologists, 82% reported they were fairly or extremely comfortable discussing conservative care, but only 28% usually or always offered this option for older (>75 years) patients approaching kidney failure. They used various terminology for this care, with conservative management and non-dialysis care mentioned most often. Among patients, 5% of those >75 years reported receiving information about this option and 2% preferring it.

CONCLUSIONS

Although reported by nephrologists to be widely available and easily discussed, conservative care is only occasionally offered to older patients, most of whom report they were not informed of this option. The lack of a person or team responsible for conservative care and unclear information appear to be key barriers to its implementation.

Predicting Kidney Failure, Cardiovascular Disease and Death in Advanced CKD Patients

INTRODUCTION

Predicting the timing and occurrence of kidney replacement therapy (KRT), cardiovascular events, and death among patients with advanced chronic kidney disease (CKD) is clinically useful and relevant. We aimed to externally validate a recently developed CKD G4+ risk calculator for these outcomes and to assess its potential clinical impact in guiding vascular access placement.

METHODS

We included 1517 patients from the European Quality (EQUAL) study, a European multicentre prospective cohort study of nephrology-referred advanced CKD patients aged ≥65 years. Model performance was assessed based on discrimination and calibration. Potential clinical utility for timing of referral for vascular access placement was studied with diagnostic measures and decision curve analysis (DCA).

RESULTS

The model showed a good discrimination for KRT and "death after KRT," with 2-year concordance (C) statistics of 0.74 and 0.76, respectively. Discrimination for cardiovascular events (2-year C-statistic: 0.70) and overall death (2-year C-statistic: 0.61) was poorer. Calibration was fairly accurate. Decision curves illustrated that using the model to guide vascular access referral would generally lead to less unused arteriovenous fistulas (AVFs) than following estimated glomerular filtration rate (eGFR) thresholds.

CONCLUSION

This study shows moderate to good predictive performance of the model in an older cohort of nephrology-referred patients with advanced CKD. Using the model to guide referral for vascular access placement has potential in combating unnecessary vascular surgeries.

Evaluation of the combination effect of rutin and vitamin C supplementation on the oxidative stress and inflammation in hemodialysis patients

Background: Hemodialysis (HD) patients are at risk of malnutrition, cardiovascular complications, and all-cause mortality due to oxidative stress and inflammation. Some studies have demonstrated that rutin attenuates oxidative stress and inflammation in CKD rats, but its effects in HD patients are unknown to date. Aim: The aim of this study was to evaluate the effect of rutin and vitamin C versus vitamin C alone on oxidative stress and inflammation in HD patients. Methods: A prospective randomized, open-label, controlled trial enrolled on hundred and five HD patients divided into three groups as follows: patients in group 1 were given a rutin/vitamin C combination (Ruta C group as the combination trade name is known as Ruta C 60 tablets), patients in group 2 were given vitamin C (1 g) (vitamin C group), and group 3 was the control group; the study period was 16 weeks. The following were assessed at baseline and at the end of the study: serum malondialdehyde (MDA), glutathione peroxidase (GPx), high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), lipid profile levels, and erythrocyte sedimentation rate. Results: It was found that vitamin C significantly increased serum GPx in group 2 (p = 0.001) compared to a non-significant result in both group 1 and 3; in addition, serum MDA and TNF-α values had decreased significantly in the three groups compared to their baselines; however, a non-significant difference was seen among the studied groups at the end of the study. On the other hand, MDA levels were reduced by 50% in interventional groups compared to 28% in the control group, while the Ruta C group showed an 80% reduction in the level of TNF α compared to the 78% reduction observed in the vitamin C group, and finally, the interventional drugs showed a significant improvement in the lipid profile. Conclusion: Vitamin C supplementation alone for 16 weeks had a potential effect on the antioxidant's GPx activity. Moreover, it was reported that both vitamin C alone or the rutin/vitamin C combination (Ruta C) showed a protective role against lipid peroxidation, evidenced by the reduced levels of MDA. Finally, rutin had a favorable synergistic effect with vitamin C in reducing TG and TNF-α levels and increasing HDL-C level.

Information and consensus document for the detection and management of chronic kidney disease

Chronic kidney disease (CKD) is a major public health problem worldwide that affects more than 10% of the Spanish population. CKD is associated with high comorbidity rates, poor prognosis and major consumption of health system resources. Since the publication of the last consensus document on CKD seven years ago, little evidence has emerged and few clinical trials on new diagnostic and treatment strategies in CKD have been conducted, apart from new trials in diabetic kidney disease. Therefore, CKD international guidelines have not been recently updated. The rigidity and conservative attitude of the guidelines should not prevent the publication of updates in knowledge about certain matters that may be key in detecting CKD and managing patients with this disease. This document, also prepared by 10 scientific associations, provides an update on concepts, clarifications, diagnostic criteria, remission strategies and new treatment options. The evidence and the main studies published on these aspects of CKD have been reviewed. This should be considered more as an information document on CKD. It includes an update on CKD detection, risk factors and screening; a definition of renal progression; an update of remission criteria with new suggestions in the older population; CKD monitoring and prevention strategies; management of associated comorbidities, particularly in diabetes mellitus; roles of the Primary Care physician in CKD management; and what not to do in Nephrology. The aim of the document is to serve as an aid in the multidisciplinary management of the patient with CKD based on current recommendations and knowledge.

Effect of sodium-glucose cotransporter-2 (SGLT2) inhibitors on serum urate levels in patients with and without diabetes: a systematic review and meta-regression of 43 randomized controlled trials

Objectives

Sodium-glucose cotransporter-2 (SGLT2) inhibitors have been found to reduce serum urate in patients with type 2 diabetes mellitus. To evaluate if this effect applies to both patients with and without diabetes, we conducted a systematic review and meta-analysis of SGLT2 inhibitors on serum urate levels in this population.

Methods

Four electronic databases (PubMed, Embase, Cochrane and SCOPUS) were searched on 25 September 2021 for articles published from 1 January 2000 up to 25 September 2021, for studies that examined the effect of SGLT2 inhibitors on serum urate in study subjects. Random-effects meta-analysis was performed, with subgroup analyses on the type of SGLT2 inhibitor agent administered, presence of type 2 diabetes mellitus, presence of chronic kidney disease and drug dose.

Results

A total of 43 randomized controlled trials, with a combined cohort of 31,921 patients, were included. Both patients with [-31.48 μmol/L; 95% confidence interval (CI): -37.35 to -25.60] and without diabetes (-91.38 μmol/L; 95% CI: -126.53 to -56.24) on SGLT2 inhibitors had significantly lower urate levels when compared with placebo. This treatment effect was similarly observed across different types of SGLT2 inhibitors. However, in type 2 diabetes mellitus (T2DM) patients with chronic kidney disease, the reduction in serum urate with SGLT2 inhibitors became insignificant (95% CI: -22.17 to 5.94, p < 0.01).

Conclusion

This study demonstrated that SGLT2 inhibitors are beneficial in reducing serum urate in patients with and without diabetes. SGLT2 inhibitors could therefore contribute to the general treatment of hyperuricaemia.

Independent External Validation and Comparison of Death and Kidney Replacement Therapy Prediction Models in Advanced CKD

Rationale & Objective

Study Design

Setting & Participants

Outcomes & Analytical Approach

Results

Limitations

Conclusions

Analysis of eGFR index category and annual eGFR slope association with adverse clinical outcomes using real-world Japanese data: a retrospective database study

OBJECTIVES

Real-world clinical outcome data of patients with an above-normal estimated glomerular filtration rate (eGFR) and increasing eGFR over time (eGFR slope) are scarce. Although eGFR is commonly recorded, eGFR slopes are rarely used for adverse outcome risk categorisation in clinical practice. We investigated the association of above-normal/below-normal eGFR ranges and increasing/declining eGFR slopes with clinical outcomes in Japan.

DESIGN

Observational cohort study.

SETTING

Primary and acute care hospitals; 423 centres.

PARTICIPANTS

57 452 patients aged ≥16 years with ≥3 eGFR values (latest available January 2013-December 2016) from the Japanese Medical Data Vision database were stratified into six index eGFR and six eGFR slope groups (slopes calculated using a linear mixed model).

PRIMARY AND SECONDARY OUTCOME MEASURES

Time-to-event analyses of cardiovascular mortality, all-cause mortality (ACM), all-cause hospitalisation (ACH) and cardiovascular and major kidney events. eGFR and slope groups were analysed by Cox proportional hazard models with multivariable adjustment, using normal eGFR/little-to-no slope groups as reference.

RESULTS

Higher risk of clinical outcomes was observed with declining eGFR slope groups versus the reference group; the HR (95% CI) for slope ≤-5 mL/min/1.73 m²/year: cardiovascular events 1.8 (1.4 to 2.2), ACH 1.8 (1.5 to 2.1), and ACM 2.8 (1.9 to 4.2) and was non-significant for kidney events 1.5 (0.9 to 2.5). A similar, but non-significant, pattern was observed with increasing slope groups (slope >3 mL/min/1.73 m²/year HR (95% CI): cardiovascular events 1.2 (0.9 to 1.5), ACH 1.1 (0.9 to 1.4) and ACM 1.5 (0.9 to 2.3)).Above-normal and below-normal eGFR groups were associated with poorer outcomes versus the reference group, but kidney events were associated with below-normal eGFR only.

CONCLUSION

Poorer clinical outcomes were observed not only for below-normal eGFR and declining eGFR slope groups but also for certain above-normal eGFR and increasing slope groups. eGFR and eGFR slope may, therefore, be useful for identifying patients at high risk of adverse clinical outcomes.

Risk Factors for Progression of CKD with and without Diabetes

OBJECTIVE

We aim to identify independent risk factors to predict CKD progression to end stage renal disease (ESRD) in patients with or without diabetes.

METHODS

In this retrospective study, we enrolled CKD stage 3-4 patients between January 2013 and December 2018 and followed them until December 2020 or the initiation of dialysis. We used Kaplan-Meier to plot the survival curve. Univariate and multivariable Cox proportional hazards model was used to explore risk factors affecting the progression of CKD. The final model was used to construct nomogram for predicting CKD progression. Calibration plots and concordance index (C-index) were used to evaluate the accuracy and discrimination of the risk model.

RESULTS

We enrolled 309 CKD patients, including 80 cases in G3a, 98 cases in G3b, and 131 cases in G4. Among them, 141 patients had diabetes and 168 did not. The mean age of patients at enrolled was 57.86 ± 15.10 years, and 67% were male. The median follow-up time was 25.6 months. There were 81 patients (26.2%) that started dialysis in the total CKD cohort, 52 cases (36.9%) in the CKD with diabetes group, and 29 cases (17.3%) in the CKD without diabetes group. Hypoalbuminemia (HR =2.655, P < 0.001), proteinuria (HR =2.592, P = 0.042), increased LDL (HR =2.494, P < 0.001), diabetes (HR =2.759, P < 0.001), hypertension (HR =3.471, P = 0.037), and CKD stage (HR =2.001, P = 0.046) were risk factors for CKD progression to ESRD in the overall population. For those without diabetes, only hypoalbuminemia (HR =2.938, P = 0.030) was a risk factor for CKD progression to ESRD. For those with diabetes, both hypoalbuminemia (HR =2.758, P = 0.002), the increased level of LDL (HR =3.982, P < 0.001), and CKD stage (HR =3.781, P = 0.001) were risk factors for CKD progression to ESRD. The C-index of the final nomograms was 0.760 (P < 0.001).

CONCLUSIONS

The results from our risk factor model suggest that CKD disease progression can be predicted and early strategic intervention is necessary for CKD patients to avoid renal function deterioration.

Clinical events and patient-reported outcome measures during CKD progression: findings from the Chronic Renal Insufficiency Cohort Study

BACKGROUND

Patients with chronic kidney disease (CKD) face risks of not only end-stage kidney disease (ESKD), cardiovascular disease (CVD) and death, but also decline in kidney function, quality of life (QOL) and mental and physical well-being. This study describes the multidimensional trajectories of CKD using clinical events, kidney function and patient-reported outcome measures (PROMs). We hypothesized that more advanced CKD stages would associate with more rapid decline in each outcome.

METHODS

Among 3939 participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study, we evaluated multidimensional disease trajectories by G- and A-stages of enrollment estimated glomerular filtration rate (eGFR) and albuminuria, respectively. These trajectories included clinical events (ESKD, CVD, heart failure and death), eGFR decline and PROMs [kidney disease QOL (KDQOL) burden, effects and symptoms questionnaires, as well as the 12-item short form mental and physical component summaries]. We also evaluated a group-based multitrajectory model to group participants on the basis of longitudinal PROMs and compared group assignments by enrollment G- and A-stage.

RESULTS

The mean participant age was 58 years, 45% were women, mean baseline eGFR was 44 mL/min/1.73 m2 and median urine albumin:creatinine ratio was 52 mg/g. The incidence of all clinical events was greater and eGFR decline was faster with more advanced G- and A-stages. While baseline KDQOL and physical component measures were lower with more advanced G- and A-stage of CKD, changes in PROMs were inconsistently related to the baseline CKD stage. Groups formed on PROM trajectories were fairly distinct from existing CKD staging (observed agreement 60.6%) and were associated with the risk of ESKD, CVD, heart failure and death.

CONCLUSIONS

More advanced baseline CKD stage was associated with a higher risk of clinical events and faster eGFR decline, and was only weakly related to changes in patient-reported metrics over time.

[CKD care in French nephrology practices]

BACKGROUND

To be able to assess the impact of the bundled payment system on real-life management of patients with chronic kidney disease, an overview of patient-care management before its implementation is needed.

PATIENTS AND METHODS

We describe patterns of nephrology care over 3 years in 2835 patients with moderate to severe chronic kidney disease, who were followed-up from 2013 to 2019 in the CKD-REIN cohort study. Compliance with health authority guidelines during this period is also studied.

RESULTS

At baseline, patients' mean age was 67 years, 65% were men, and 43% had chronic kidney disease stage 4 or 5. The mean number of nephrology visits increased from 1.1 to 2.7 per year, from chronic kidney disease stage 3A to stage 5. The minimum number of nephrology visits as recommended by health authorities was achieved in 84%, 63%, and 33% of patients with chronic kidney disease stages 3B, 4, and 5, respectively. In chronic kidney disease stages 4 and 5, only 34% and 40% of patients had seen a dietitian, and 33% and 54% had received information about treatment options, respectively. The average waiting time for a first appointment with a nephrologist was longer, 60 days and its duration shorter, 30 vs 38 to 40 minutes, in university hospitals compared with non-university hospitals and private clinics.

CONCLUSION

The significant gap between received and recommended care reflects human resources and organizational limits in chronic kidney disease management in the nephrology setting. Improvements with bundled payment are expected.

Right Ventricular Functionality Following Hemodialysis Initiation in End-Stage Kidney Disease-A Single-Center, Prospective, Cohort Study

Background and Objectives: Two-dimensional speckle tracking echocardiography (2D-STE) is viewed as an outstanding technique, competent of uncovering earlier subclinical myocardial anomalies compared to conventional echocardiography. A few endeavors adopted 2D-STE as a tool to estimate right ventricular (RV) function in subjects with end-stage kidney disease (ESKD). There is no published prospective study on an adult ESKD cohort exploring the consequences of commencing elective hemodialysis (HD) on RV behavior. Materials and Methods: We investigated the RV systolic function using traditional (tricuspid annular plane systolic excursion-TAPSE, RV fractional area change-FAC) and 2D-STE (RV free wall longitudinal strain-RVFWLS) parameters following the initiation of HD. We enrolled 79 consecutive patients with ESKD and assessed them in four steps-at baseline, before HD, and at 3, 6, and 12 months. Results: RVFWLS, FAC, and TAPSE values had a significant increase at 3, 6, and 12 months from baseline (p < 0.001) and a significant increase at 6 months from 3 months (p < 0.001). However, differences between 12 months and 6 months were not significant (p > 0.05) according to Dunn-Bonferroni post hoc tests. Seventeen deaths were recorded before the completion of the study. RVFWLS, FAC, and TAPSE values significantly decreased at 3 and 6 months in all 17 deceased patients, in clear opposition with the values survivors had. All the studied parameters had a significant prediction power on mortality (p < 0.001) having an outstanding performance: baseline-RVFWLS (AUC: 1.000 (95% C.I.: 1.000-1.000)), baseline-FAC (AUC: 0.974 (95% C.I.: 0.942-1.000)), and baseline-TAPSE (AUC: 0.962 (95% C.I.: 0.920-1.000). Conclusions: Our study is the first to investigate RV function by 2D-STE and correlate it with traditional methods in patients with ESKD before and after the initiation of HD. RV function was significantly ameliorated at 3, 6, and 12 months compared to the pre-HD values. FAC and RVFWLS gain an outstanding prognostic role on mortality in this population.

Management of Kidney Failure in Patients with Diabetes Mellitus: What Are the Best Options?

Diabetic kidney disease (DKD) is the most frequent cause of kidney failure (KF). There are large variations in the incidence rates of kidney replacement therapy (KRT). Late referral to nephrology services has been associated with an increased risk of adverse outcomes. In many countries, when patients reach severely reduced glomerular filtration rate (GFR), they are managed by multidisciplinary teams led by nephrologists. In these clinics, efforts will continue to halt chronic kidney disease (CKD) progression and to prevent cardiovascular mortality and morbidity. In patients with diabetes and severely reduced GFR and KF, treating hyperglycemia is a challenge, since some drugs are contraindicated and most of them require dose adjustments. Even more, a decision-making process will help in deciding whether the patient would prefer comprehensive conservative care or KRT. On many occasions, this decision will be conditioned by diabetes mellitus itself. Effective education should cover the necessary information for the patient and family to answer these questions: 1. Should I go for KRT or not? 2. If the answer is KRT, dialysis and/or transplantation? 3. Dialysis at home or in center? 4. If dialysis at home, peritoneal dialysis or home hemodialysis? 5. If transplantation is desired, discuss the options of whether the donation would be from a living or deceased donor. This review addresses the determinant factors with an impact on DKD, aiming to shed light on the specific needs that arise in the management and recommendations on how to achieve a comprehensive approach to the diabetic patient with chronic kidney disease.

Impacts of Interaction of Mental Condition and Quality of Life between Donors and Recipients at Decision-Making of Preemptive and Post-Dialysis Living-Donor Kidney Transplantation

Pre-emptive kidney transplantation (PEKT) is considered one of the most effective types of kidney replacement therapies to improve the quality of life (QOL) and physical prognosis of patients with end-stage renal disease (ESRD). In Japan, living-donor kidney transplantation is a common therapeutic option for patients undergoing dialyses (PDKT). Moreover, during shared decision-making in kidney replacement therapy, the medical staff of the multidisciplinary kidney team often provide educational consultation programmes according to the QOL and sociopsychological status of the ESRD patient. In Japan, the majority of kidney donations are provided by living family members. However, neither the psychosocial status of donors associated with the decision-making of kidney donations nor the interactions of the psychosocial status between donors and recipients have been clarified in the literature. In response to this gap, the present study determined the QOL, mood and anxiety status of donors and recipients at kidney transplantation decision-making between PEKT and PDKT. Deterioration of the recipient's QOL associated with "role physical" shifted the decision-making to PEKT, whereas deterioration of QOL associated with "role emotional" and "social functioning" of the recipients shifted the decision-making to PDKT. Furthermore, increased tension/anxiety and depressive mood contributed to choosing PDKT, but increased confusion was dominantly observed in PEKT recipients. These direct impact factors for decision-making were secondarily regulated by the trait anxiety of the recipients. Unlike the recipients, the donors' QOL associated with vitality contributed to choosing PDKT, whereas the physical and mental health of the donors shifted the decision-making to PEKT. Interestingly, we also detected the typical features of PEKT donors, who showed higher tolerability against the trait anxiety of reactive tension/anxiety than PDKT donors. These results suggest that choosing between either PEKT or PDKT is likely achieved through the proactive support of family members as candidate donors, rather than the recipients. Furthermore, PDKT is possibly facilitated by an enrichment of the life-work-family balance of the donors. Therefore, multidisciplinary kidney teams should be aware of the familial psychodynamics between patients with ESRD and their family members during the shared decision-making process by continuing the educational consultation programmes for the kidney-replacement-therapy decision-making process.

Kidney Failure Prediction Models: A Comprehensive External Validation Study in Patients with Advanced CKD

BACKGROUND

Various prediction models have been developed to predict the risk of kidney failure in patients with CKD. However, guideline-recommended models have yet to be compared head to head, their validation in patients with advanced CKD is lacking, and most do not account for competing risks.

METHODS

To externally validate 11 existing models of kidney failure, taking the competing risk of death into account, we included patients with advanced CKD from two large cohorts: the European Quality Study (EQUAL), an ongoing European prospective, multicenter cohort study of older patients with advanced CKD, and the Swedish Renal Registry (SRR), an ongoing registry of nephrology-referred patients with CKD in Sweden. The outcome of the models was kidney failure (defined as RRT-treated ESKD). We assessed model performance with discrimination and calibration.

RESULTS

The study included 1580 patients from EQUAL and 13,489 patients from SRR. The average c statistic over the 11 validated models was 0.74 in EQUAL and 0.80 in SRR, compared with 0.89 in previous validations. Most models with longer prediction horizons overestimated the risk of kidney failure considerably. The 5-year Kidney Failure Risk Equation (KFRE) overpredicted risk by 10%-18%. The four- and eight-variable 2-year KFRE and the 4-year Grams model showed excellent calibration and good discrimination in both cohorts.

CONCLUSIONS

Some existing models can accurately predict kidney failure in patients with advanced CKD. KFRE performed well for a shorter time frame (2 years), despite not accounting for competing events. Models predicting over a longer time frame (5 years) overestimated risk because of the competing risk of death. The Grams model, which accounts for the latter, is suitable for longer-term predictions (4 years).

The impact of diabetes on heart failure development: The cardio-renal-metabolic connection

Heart failure (HF) and chronic kidney disease (CKD) are often associated in type 2 diabetes (T2D), aggravate each other and exert synergistic effects to increase the risk of cardiac and renal events. The risks of renal worsening in HF patients and HF in CKD patients need to be evaluated to tailor preventive therapy. The recent CV and renal trials enriched our knowledge about the natural history of HF and CKD in T2D and provided evidence for the benefit of sodium-glucose cotransporter 2 inhibitors (SGLT2is) in HF and renal decline prevention. SGLT-2is are the best choice in patients with HFrEF to improve CV prognosis and HF-related outcomes and also to prevent kidney-related outcomes, and in CKD patients to slow down renal failure and also reduce hospitalization for HF and CV death. In both situations the number of patients to treat in order to prevent such events in one patient is lower than in the general T2D population at high CV risk. GLP1-receptor agonists could be an alternative in a patient who is intolerant or has a contraindication to SGLT-2is. A tight collaboration between diabetologists, nephrologists and cardiologists should be encouraged for a holistic and effective strategy to reduce the burden of cardio-renal-metabolic interaction.

Renin-angiotensin system blockade in patients with chronic kidney disease: benefits, problems in everyday clinical use, and open questions for advanced renal dysfunction

Management of hypertension and albuminuria are considered among the primary goals of treatment to slow the progression of chronic kidney disease (CKD). Renin-angiotensin system (RAS) blockers, i.e., angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) are the main drugs to achieve these goals. Seminal studies have showed that RAS blockers present significant renoprotective effects in CKD patients with very high albuminuria. In post hoc analyses of such trials, these renoprotective effects appeared more robust in patients with more advanced CKD. However, randomized trials specifically addressing whether RAS blockers should be initiated or maintained in patients with advanced CKD are scarce and do not include subjects with normoalbuminuria, thus, many clinicians are unconvinced for the beneficial effects of RAS blockade in these patients. Further, the fear of hyperkalemia or acute renal decline is another factor due to which RAS blockers are usually underprescribed and are easily discontinued in patients with more advanced CKD; i.e., those in Stages 4 and 5. This review summarizes evidence from the literature regarding the use of RAS blockers in patients with advanced CKD.

[Chronic kidney disease among adults in Rio Branco, State of Acre: a population-based survey]

The scope of this study was to establish the prevalence of CKD and associated factors among young adults (18-59 years of age) from Rio Branco in the State of Acre. It involved a population-based survey conducted in 2014, in the urban and rural areas of the municipality and CKD was defined as the glomerular filtration rate (GFR) < 60ml/min/1.73m², estimated by the CKD-EPI, and the presence of albuminuria > 29 mg/g. Association measures were estimated by logistic regression, with a confidence level of 95%. The overall prevalence of CKD was 6.2%. The presence of CKD was higher among women, aged 40 to 59 years, with non-white skin color, with lower schooling, and of sedentary disposition. There were statistically significant differences in the distribution according to the presence of CKD in the hypertension, diabetes and hospitalization variables over the past 12 months. CKD among adults was associated with the female sex (OR: 2.41, 95%CI: 1.14-5.12), diabetes (OR: 4.67, 95%CI: 1.28-17.03) and arterial hypertension (OR: 1.98; 95%CI: 1.16-3.37). CKD reveals a high prevalence and is associated with chronic diseases, calling for the need for public health measures for early detection and prevention of its progression.

Cardiovascular disease history and β-blocker prescription patterns among Japanese and American patients with CKD: a cross-sectional study of the CRIC and CKD-JAC studies

Cardiovascular disease (CVD) is a major complication in individuals with chronic kidney disease (CKD). In Japan, the incidence of CVD among persons with CKD is lower than that in the United States. Although various classes of antihypertensive agents are prescribed to prevent CVD, the proportion varies between the United States and Japan. Until now, few studies have compared clinical practices and CVD prevalence among patients with CKD in the United States vs. Japan. In this study, we performed a cross-sectional comparison of the prevalence of CVD and the prescription of β-blockers at study entry to the Chronic Kidney Disease Japan Cohort (CKD-JAC) Study and the Chronic Renal Insufficiency Cohort (CRIC) Study. The mean patient age was 58.2 and 60.3 years, the mean estimated glomerular filtration rate (eGFR) was 42.8 and 28.9 (mL/min/1.73 m²), and the median urinary albumin:creatinine ratio was 51.9 and 485.9 (mg/g) among 3939 participants in the CRIC Study and 2966 participants in the CKD-JAC Study, respectively. The prevalence of any CVD according to a self-report (CRIC Study) was 33%, while that according to a medical chart review (CKD-JAC Study) was 24%. These findings were consistent across eGFR levels. Prescriptions for β-blockers differed between the CRIC and CKD-JAC Studies (49% and 20%, respectively). The odds ratios for the association of any history of CVD and β-blocker prescription were 3.0 [2.6-3.5] in the CRIC Study and 2.0 [1.6-2.5] in the CKD-JAC Study (P < 0.001 for the interaction). In conclusion, the prevalence of CVD and treatment with β-blockers were higher in the CRIC Study across eGFR levels.

External validation of prognostic models: what, why, how, when and where?

Prognostic models that aim to improve the prediction of clinical events, individualized treatment and decision-making are increasingly being developed and published. However, relatively few models are externally validated and validation by independent researchers is rare. External validation is necessary to determine a prediction model's reproducibility and generalizability to new and different patients. Various methodological considerations are important when assessing or designing an external validation study. In this article, an overview is provided of these considerations, starting with what external validation is, what types of external validation can be distinguished and why such studies are a crucial step towards the clinical implementation of accurate prediction models. Statistical analyses and interpretation of external validation results are reviewed in an intuitive manner and considerations for selecting an appropriate existing prediction model and external validation population are discussed. This study enables clinicians and researchers to gain a deeper understanding of how to interpret model validation results and how to translate these results to their own patient population.

Experience of the first 6 years of pediatric kidney transplantation in Indonesia: A multicenter retrospective study

BACKGROUND

Pediatric kidney transplantation was only introduced in Indonesia in 2013. We therefore aimed to assess the characteristics and outcomes of transplants performed from its inception to January 2019.

METHOD

The study had a dual-center retrospective design. We examined the records of kidney transplant recipients and then calculated patient and graft survival rates by Kaplan-Meier survival analysis with 95% confidence intervals (95% CI).

RESULTS

In total, 12 kidney transplantations were performed in eleven children during the study period; among these, ten were boys, and nine had renal failure caused by congenital anomaly of the kidney or urinary tract. All donors were living, and all recipients were on dialysis at the time of transplantation, when their median age was 14.5 years (range, 8-19 years). Three patients died of infection in the first year of follow-up and two lost their allograft by the time of their last follow-up (median, 13 months; range, 4-69 months). The 1-year patient survival rate was therefore 68.18% (95% CI, 29.72%-88.61%), which remained unchanged at 3 and 5 years. However, the non-death-censored graft survival rates at 1, 3, and 5 years were 68.18% (95% CI, 29.72%-88.61%), 51.14% (95% CI, 14.5%-79.46%), and 25.57% (95% CI, 1.38%-64.78%), respectively.

CONCLUSION

Patient and graft survival rates after pediatric kidney transplantation in Indonesia are lower than those reported in other countries. Closer patient follow-up and stricter adherence to guidelines could improve transplant outcomes, but we must seek to improve the balance between infection and rejection.

Comparative Effectiveness of Renin-Angiotensin System Inhibitors and Calcium Channel Blockers in Individuals With Advanced CKD: A Nationwide Observational Cohort Study

RATIONALE & OBJECTIVE

It is unknown whether initiating renin-angiotensin system (RAS) inhibitor therapy in patients with advanced chronic kidney disease (CKD) is superior to alternative antihypertensive agents such as calcium channel blockers (CCBs). We compared the risks for kidney replacement therapy (KRT), mortality, and major adverse cardiovascular events (MACE) in patients with advanced CKD in routine nephrology practice who were initiating either RAS inhibitor or CCB therapy.

STUDY DESIGN

Observational study in the Swedish Renal Registry, 2007 to 2017.

SETTINGS & PARTICIPANTS

2,458 new users of RAS inhibitors and 2,345 CCB users with estimated glomerular filtration rates<30mL/min/1.73m² (CKD G4-G5 without KRT) who were being followed up by a nephrologist. As a positive control cohort, new users of the same drugs with CKD G3 (estimated glomerular filtration rate, 30-60mL/min/1.73m²) were evaluated.

EXPOSURES

RAS inhibitor versus CCB therapy initiation.

OUTCOME

Initiation of KRT (maintenance dialysis or transplantation), all-cause mortality, and MACE (composite of cardiovascular death, myocardial infarction, or stroke).

ANALYTICAL APPROACH

HRs with 95% CIs were estimated using propensity score-weighted Cox proportional hazards regression adjusting for demographic, clinical, and laboratory covariates.

RESULTS

Median age was 74 years, 38% were women, and median follow-up was 4.1 years. After propensity score weighting, there was significantly lower risk for KRT after new use of RAS inhibitors compared with new use of CCBs (adjusted HR, 0.79 [95% CI, 0.69-0.89]) but similar risks for mortality (adjusted HR, 0.97 [95% CI, 0.88-1.07]) and MACE (adjusted HR, 1.00 [95% CI, 0.88-1.15]). Results were consistent across subgroups and in as-treated analyses. The positive control cohort of patients with CKD G3 showed similar KRT risk reduction (adjusted HR, 0.67 [95% CI, 0.56-0.80]) with RAS inhibitor therapy compared with CCBs.

LIMITATIONS

Potential confounding by indication.

CONCLUSIONS

Our findings provide evidence from real-world clinical practice that initiation of RAS inhibitor therapy compared with CCBs may confer kidney benefits among patients with advanced CKD, with similar cardiovascular protection.

Initiation of Hemodialysis After Eight Years Following the Diagnosis of Stage 5 Chronic Kidney Disease: A Case Report

With the growing global rates of diabetes and hypertension, chronic kidney disease (CKD) appears to be a major contributor to morbidity and all-cause mortality. In recent years, there has been growing controversy regarding the optimal timing for the initiation of hemodialysis in this patient cohort. In this report, we present the case of a 52-year-old female with a 15-year history of CKD who was admitted to the hospital with clinical manifestations of uremia, volume overload, and symptomatic anemia. The patient presented with fatigue, nausea, progressive shortness of breath, and lightheadedness for two weeks, which had limited the activities of daily living. For the past eight years, her estimated glomerular filtration rate (GFR) had ranged from 5 to 15 mL/min/1.73 m2, consistent with kidney failure seen in stage 5 CKD. Prior to her recent admission, the patient had been grossly asymptomatic and had been responsive to medical therapy. After appropriate management with hemodialysis, a transfusion of packed red blood cells, and medication adjustment, the patient was scheduled for maintenance dialysis through an arteriovenous fistula. She had no further complaints and her laboratory abnormalities were found normalized at the six-month follow-up. This case report presents the survival and outcome of a patient with stage 5 CKD, who was only initiated on hemodialysis eight years after her diagnosis.

Long-term renal outcomes after elective percutaneous coronary intervention in patients with advanced renal dysfunction

The aim of the present study was to evaluate the renal outcomes, including the time course of renal function, after elective PCI in patients with advanced renal dysfunction and to assess the predictors of renal dysfunction progression. This is a subanalysis of a previous observational multicenter study that investigated long-term clinical outcomes in patients with advanced renal dysfunction (eGFR < 30 mL/min/1.73 m²), focusing on 151 patients who underwent elective PCI and their long-term renal outcomes. Renal dysfunction progression was defined as a 20% relative decrease in eGFR at 1 year from baseline or the initiation of permanent dialysis within 1 year. Progression of renal dysfunction at 1 year occurred in 42 patients (34.1%). Among patients with renal dysfunction progression, the decrease of renal function from baseline was not observed at 1 month but after 6 months of the index PCI. Baseline eGFR and serum albumin level were significant predictors of renal dysfunction progression at 1 year. Among 111 patients who had not been initiated on dialysis within 1 year, those with renal dysfunction progression had a significantly higher incidence of dialysis initiation more than 1 year after the index PCI than those with preserved renal function (p < 0.001). Among patients with advanced renal dysfunction who underwent elective PCI, 34.1% showed renal dysfunction progression at 1 year. The decrease in renal function was not observed at 1 month but after 6 months of the index PCI in patients with renal dysfunction progression. Furthermore, patients with renal dysfunction progression had poorer long-term renal outcomes.

Association Between β-Blocker Use and Mortality/Morbidity in Patients With Heart Failure With Reduced, Midrange, and Preserved Ejection Fraction and Advanced Chronic Kidney Disease

Background:

It is unknown if β-blockers reduce mortality/morbidity in patients with heart failure (HF) and advanced chronic kidney disease (CKD), a population underrepresented in HF trials.

Methods:

Observational cohort of HF patients with advanced CKD (estimated glomerular filtration rate <30 mL/min per 1.73 m 2 ) from the Swedish Heart Failure Registry between 2001 and 2016. We first explored associations between β-blocker use, 5-year death, and the composite of cardiovascular death/HF hospitalization among 3775 patients with HF with reduced ejection fraction (HFrEF) and advanced CKD. We compared observed hazards with those from a control cohort of 15 346 patients with HFrEF and moderate CKD (estimated glomerular filtration rate <60–30 mL/min per 1.73 m 2 ), for whom β-blocker trials demonstrate benefit. Second, we explored outcomes associated to β-blocker among advanced CKD participants with preserved (HFpEF; N=2009) and midrange ejection fraction (HFmrEF; N=1514).

Results:

During a median follow-up of 1.3 years, 2012 patients had a subsequent HF hospitalization, and 2849 died in the HFrEF cohort, of which 2016 died due to cardiovascular causes. Among patients with HFrEF, β-blocker use was associated with lower risk of death (adjusted hazard ratio 0.85 [95% CI, 0.75–0.96]) and cardiovascular mortality/HF hospitalization (0.87 [0.77–0.98]) compared with nonuse. The magnitude of the associations was similar to that observed for HFrEF patients with moderate CKD. Conversely, no significant association was observed for β-blocker users in advanced CKD with HFpEF (death: 0.88 [0.77–1.02], cardiovascular mortality/HF hospitalization: 1.05 [0.90–1.23]) or HFmrEF (death: 0.95 [0.79–1.14], cardiovascular mortality/HF hospitalization: 1.09 [0.90–1.31]).

Conclusions:

In HFrEF patients with advanced CKD, the use of β-blockers was associated with lower morbidity and mortality. Although inconclusive due to limited power, these benefits were not observed in similar patients with HFpEF or HFmrEF.

Association of Volume Overload With Kidney Function Outcomes Among Patients With Heart Failure With Reduced Ejection Fraction

Introduction

In patients with heart failure with reduced ejection fraction (HFrEF), volume overload is associated with mortality. Few studies that have examined the relation between volume and long-term kidney function outcomes in HFrEF.

Methods

Using data from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) trial, we used multivariable Cox regression models to evaluate the association between volume overload as evaluated by B-type natriuretic peptide (BNP) and N-terminal pro B-type natriuretic peptide (NT-proBNP), and a clinical congestion score (scale of 0–12) composed of pedal edema, jugular venous distension, rales, and orthopnea with the occurrence of estimated glomerular filtration rate (eGFR) decline by >40%, and incident chronic kidney disease (CKD) stage ≥4 defined by eGFR of <30 ml/min per 1.73 m², over a median 10-month follow-up.

Results

Among 3718 patients (mean eGFR 59 ± 22 ml/min per 1.73 m²), 340 (9%) reached an eGFR decline >40% and 337 (10%) developed incident CKD stage ≥4. In multivariable models, compared with those in the quartile of lowest NT-proBNP, those within the highest quartile had a significantly higher risk of eGFR decline by >40% (hazard ratio [HR] = 2.62 [95% confidence interval {CI} = 1.62, 4.23]) and incident CKD stage ≥4 (HR = 2.66 [95% CI = 1.49, 4.77]), with similar trends for BNP. Similarly in multivariable models, patients in the quartile of highest congestion score had a 48% increased risk for eGFR decline by >40% (HR = 1.48 [95% CI = 1.07, 2.06]) and a 42% increased risk for CKD stage ≥4 (HR = 1.42 [95% CI = 1.01, 1.99]), compared with the lowest quartile.

Conclusion

Volume overload, as indicated both by elevated natriuretic peptides and clinical signs and symptoms, is associated with increased risk for clinically important kidney function outcomes in HFrEF.

Chronic kidney disease progression and mortality risk profiles in Germany: results from the Chronic Kidney Disease Outcomes and Practice Patterns Study

BACKGROUND

Chronic kidney disease (CKD) progression among German patients in a representative setting has not been described previously. The Verband Deutsche Nierenzentren and Chronic Kidney Disease Outcomes and Practice Patterns Study established a longitudinal observational cohort among German CKD patients to research variations in patient care and outcomes in real-world nephrology practices.

METHODS

A cohort of CKD Stages 3 (25%) and 4 (75%) patients was established from German nephrologist-run CKD clinics in 2013-16. Linear models were used to determine the estimated glomerular filtration rate (eGFR) slope during follow-up and Cox models were used to assess outcomes of end-stage kidney disease (ESKD) and death.

RESULTS

A total of 1834 patients (median age 75 years, 58% male, 42% diabetics, median baseline eGFR 25 mL/min/1.73 m2) were followed for a median of 29 months. More than 50% had slow or no decline and 17% declined ≥5 mL/min/1.73 m2/year. After 4.5 years, the incidence of ESKD was 8% and of deaths without ESKD 16% among patients with eGFR ≥30 mL/min/1.73 m2 and 37% and 19% for eGFR <30 mL/min/1.73 m2. Adjusted models showed higher risks of ESKD or death for patients with worse kidney function at baseline, male sex, diabetes and higher blood pressure; a higher risk of ESKD with higher albuminuria; and a higher risk of death with older age or cardiovascular comorbidity.

CONCLUSIONS

Routine nephrology care of patients in Germany comprises mostly elderly patients, many with slow CKD progression. Identification of risk factors for CKD progression and mortality may help guide resources by closer follow-up of high-risk patients.

Cost-analysis of persistent hyperkalaemia in non-dialysis chronic kidney disease patients under nephrology care in Italy

AIM

In patients with chronic kidney disease (CKD), hyperkalaemia (HK) (potassium level ≥ 5.0 mEq/L) is associated with poor clinical outcomes. This study provides novel insights by comparing management costs of CKD patients with normokalaemia vs those with persistent HK regularly followed in renal clinics in Italy.

METHODS

To this aim, a Markov model over life-time horizon was developed. Time to end-stage renal disease (ESRD) and time to death in CKD patients were derived from an observational multi-centre database including 1665 patients with non-dialysis CKD stage 1-5 under nephrology care in Italy (15 years follow-up). Resource use for CKD and HK management was obtained from the observational database, KDIGO international guidelines, and clinical expert opinion.

RESULTS

Results showed that patients with normokalaemia vs persistent HK brought an average per patient lifetime cost-saving of €16 059 besides delayed onset of ESRD by 2.29 years and increased survival by 1.79 years with increment in total survival and dialysis-free survival in normokalaemia that decreased from early to advanced disease. Cost-saving related to normokalaemia increased at more advanced CKD; however, it was already evident at early stage (3388.97€ at stage 1-3a). OWSA confirmed cost-saving associated with normokalaemia across all parameter variations.

DISCUSSION AND CONCLUSION

This model is the first to simulate the impact of HK in non-dialysis CKD patients on economic and clinical outcomes using real-world data from nephrology clinics. In these patients, persistent HK results into higher lifetime costs, besides poorer clinical outcomes, that are evident since the early stages of CKD. Maintaining normokalaemia should therefore be of main concern in CKD treatment planning to improve long-term economic and clinical outcomes.

The transition clinic in chronic kidney disease care

People with advanced chronic kidney disease and evidence of progression have a high risk of renal replacement therapy. Specialized transition clinics could offer a better option for preparing these patients for dialysis, transplantation or conservative care. This review focuses on the different aspects of such transition clinics. We discuss which patients should be referred to these units and when referral should take place. Patient involvement in the decision-making process is important and requires unbiased patient education. There are many themes, both patient-centred and within the healthcare structure, that will influence the process of shared decision-making and the modality choice. Aspects of placing an access for haemodialysis and peritoneal dialysis are reviewed. Finally, we discuss the importance of pre-emptive transplantation and a planned dialysis start, all with a focus on multidisciplinary collaboration at the transition clinic.

High-normal albuminuria is strongly associated with incident chronic kidney disease in a nondiabetic population with normal range of albuminuria and normal kidney function

BACKGROUND

Albuminuria and estimated glomerular filtration rate (eGFR) are clinically measured to evaluate the severity of chronic kidney disease (CKD). The aim of our study was to clarify the association between clinical parameters, including albuminuria and eGFR, and the risk of incident CKD in a nondiabetic population with normal range of albuminuria and eGFR.

METHODS

A 10-year follow-up, retrospective cohort study involving 317 Japanese men (mean age, 42 years) with eGFR ≥ 90 mL/min/1.73 m² and urine albumin-to-creatinine ratio (UACR) < 30 mg/gCr was performed. Participants were free of diabetes mellitus. Multivariate logistic regression approaches were used to assess independent predictors of the incidence of CKD.

RESULTS

Twenty-nine (9%) participants developed CKD (eGFR < 60 mL/min/1.73 m² and/or UACR ≥ 30 mg/gCr) through 10 years of follow-up. At the baseline examination, age, blood pressure, UACR, and eGFR were higher in participants who developed CKD than in those without CKD. After adjustment for confounders, high-normal albuminuria (P < 0.001) and hypertension (P = 0.045) were associated with an increased incidence of CKD. From receiver-operating characteristic curves, UACR ≥ 7.0 mg/gCr was defined as high-normal albuminuria. Logistic regression analysis also showed that, in addition to presence of hypertension, UACR ≥ 7.0 mg/gCr was identified as an independent risk of incident CKD within 10 years after adjustment for age, body mass index, smoking status, and dyslipidemia [UACR: odds ratio (OR) 17.36 (95% CI 6.16-48.93, P < 0.001)].

CONCLUSION

High-normal albuminuria and hypertension are associated with incident CKD in a nondiabetic population with normal-range UACR and eGFR.

Chronic Kidney Disease Diagnosis and Management: A Review

Importance

Chronic kidney disease (CKD) is the 16th leading cause of years of life lost worldwide. Appropriate screening, diagnosis, and management by primary care clinicians are necessary to prevent adverse CKD-associated outcomes, including cardiovascular disease, end-stage kidney disease, and death.

Observations

Defined as a persistent abnormality in kidney structure or function (eg, glomerular filtration rate [GFR] <60 mL/min/1.73 m2 or albuminuria ≥30 mg per 24 hours) for more than 3 months, CKD affects 8% to 16% of the population worldwide. In developed countries, CKD is most commonly attributed to diabetes and hypertension. However, less than 5% of patients with early CKD report awareness of their disease. Among individuals diagnosed as having CKD, staging and new risk assessment tools that incorporate GFR and albuminuria can help guide treatment, monitoring, and referral strategies. Optimal management of CKD includes cardiovascular risk reduction (eg, statins and blood pressure management), treatment of albuminuria (eg, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers), avoidance of potential nephrotoxins (eg, nonsteroidal anti-inflammatory drugs), and adjustments to drug dosing (eg, many antibiotics and oral hypoglycemic agents). Patients also require monitoring for complications of CKD, such as hyperkalemia, metabolic acidosis, hyperphosphatemia, vitamin D deficiency, secondary hyperparathyroidism, and anemia. Those at high risk of CKD progression (eg, estimated GFR <30 mL/min/1.73 m2, albuminuria ≥300 mg per 24 hours, or rapid decline in estimated GFR) should be promptly referred to a nephrologist.

Conclusions and Relevance

Diagnosis, staging, and appropriate referral of CKD by primary care clinicians are important in reducing the burden of CKD worldwide.