International comparison of the relationship of chronic kidney disease prevalence and ESRD risk

Cardiovascular Risk in Pediatric Renal Transplant Recipients

BACKGROUND

The survival of pediatric chronic kidney disease (CKD) patients has improved in recent decades due to advances in dialysis and transplantation. However, cardiovascular disease (CVD) emerges as the main cause of mortality in patients with CKD.

OBJECTIVES

To estimate cardiovascular risk in children with CKD at least 1 year after kidney transplantation. In addition, the possible association of cardiovascular risk with classic biochemical markers and potential new markers of this outcome was investigated.

METHODS

An observational ambidirectional (retrospective capture of risk factors and prospective study of outcomes) research including 75 patients who underwent renal transplant between 2003 and 2013 with postoperative follow-up of at least 1 year was conducted. The outcome variables adopted were the LV mass Z-score and the presence of coronary calcification on computed tomography using calcium Agatston score.

RESULT

Only one patient had an elevated calcium score, and three children (4%) had an LV mass Z-score ≥ 2.0. After multivariable analysis, only gender, serum triglyceride, and serum renalase concentration remained significantly associated with LV mass.

CONCLUSION

The low incidence of cardiovascular changes in the population studied confirms the benefit of transplantation for the cardiovascular health of children. Nevertheless, long-term follow-up of these patients is recommended, given the limited duration of kidney function provided by transplantation and the high likelihood of further dialysis and kidney transplants being required in these children.

Association of eGFR with stages of diabetic retinopathy and age-related macular degeneration in Indian population

PURPOSE

To investigate the influence of glomerular filtration rate in renal disease decline and its association with diabetic retinopathy (DR) and age-related macular degeneration (ARMD) in patients in South India.

METHODS

A population-based cross-sectional study was conducted including participants with DR and ARMD recruited from urban and rural populations. The data collection included medical history, anthropometric measurements, and ophthalmic work-up. The estimated glomerular filtration rate (eGFR) was calculated using the equation of chronic kidney disease-epidemiology collaboration (CKD-EPI). The grading of AMD was done by a single experienced (more than 5 years) vitreoretinal surgeon as per the International ARM Epidemiological Study Group and it was staged based on grading in the worsened eye.

RESULTS

A decline in eGFR was observed as the severity of DR increased ( P < 0.001). Baseline characteristics such as age ( P < 0.001), duration of diabetes ( P < 0.001), gender ( P < 0.001), creatinine ( P < 0.001), albumin to creatinine ratio (ACR; P < 0.001), albuminuria ( P = 0.023), blood urea ( P < 0.001), and high-density lipoprotein (HDL; P = 0.003) were found to be statistically significant. The risk for developing DR with CKD was found to be 5 times higher in male patients compared to female patients. Age and high blood urea level, diastolic blood pressure, mild and moderate DR were the risk factors associated with CKD. A decline in eGFR was observed as the severity of ARMD increased ( P < 0.001). The risk factors associated with CKD were age, gender, smoking, alcohol consumed, presence of hypertension, duration of diabetes, systolic and diastolic blood pressure, history of diabetes, body mass index (BMI), serum triglycerides, and serum HDL cholesterol.

CONCLUSION

Reduced eGFR values were associated with an increase in the severity of DR and ARMD.

Mendelian Randomization Analysis of Systemic Iron Status and Risk of Different Types of Kidney Disease

With rapid increases in incidence, diverse subtypes, and complicated etiologies, kidney disease remains a global public health problem. Iron, as an essential trace element, has pleiotropic effects on renal function and the progression of kidney diseases. A two-sample Mendelian randomization (MR) analysis was implemented to determine the potential causal effects between systemic iron status on different kidney diseases. Systemic iron status was represented by four iron-related biomarkers: serum iron, ferritin, transferrin saturation (TfSat), and total iron binding capacity (TIBC). For systemic iron status, 163,511, 246,139, 131,471, and 135,430 individuals were included in the genome-wide association study (GWAS) of serum iron, ferritin, TfSat, and TIBC, respectively. For kidney diseases, 653,143 individuals (15,658 cases and 637,485 controls), 657,076 individuals (8160 cases and 648,916 controls), and 659,320 individuals (10,404 cases and 648,916 controls) were included for immunoglobulin A nephropathy (IgAN), acute kidney disease (AKD), and chronic kidney disease (CKD), respectively. Our MR results showed that increased serum iron [odds ratio (OR): 1.10; 95% confidence interval (95% CI): 1.04, 1.16; p < 0.0042], ferritin (OR: 1.30; 95% CI: 1.14, 1.48; p < 0.0042), and TfSat (OR: 1.07; 95% CI: 1.04, 1.11; p < 0.0042)] and decreased TIBC (OR: 0.92; 95% CI: 0.88, 0.97; p < 0.0042) were associated with elevated IgAN risk. However, no significant associations were found between systemic iron status and AKD or CKD. In our MR study, the genetic evidence supports elevated systemic iron status as a causal effect on IgAN, which suggests a potential protective effect of iron chelation on IgAN patients.

Chronic Kidney Disease in Brazil: Current Status and Recommended Improvements

Background

Over the last 3 decades, over 700 million individuals worldwide have been diagnosed with chronic kidney disease (CKD). In a 2017 survey in southern Brazil, 11.4% of those surveyed had CKD. Early identification and effective therapy in Brazil may reduce CKD's impact. This panel discusses the early diagnosis and treatment of CKD and the barriers and actions needed to improve the management of CKD in Brazil. A panel of Brazilian nephrologists was provided with relevant questions to address before a multiday conference. During this meeting, each narrative was discussed and edited through several rounds until agreement on the relevant topics and recommendations was achieved.

Summary

Panelists highlighted hurdles to early diagnosis and treatment of CKD. These include, but are not limited to, a lack of public and patient education, updated recommendations, multidisciplinary CKD treatment, and a national CKD database. People-centered, physician-centered, and healthcare institution-centered actions can be taken to improve outcomes. Patient empowerment is needed via multiple channels of CKD education and access to health-monitoring wearables and apps. Primary care clinicians and nonspecialists must be trained to screen and manage CKD-causing illnesses, including diabetes and hypertension. The healthcare system may implement a national health data gathering system, more screening tests, automated test result reporting, and telehealth.

Key Messages

Increasing access to early diagnosis can provide a path to improving care for patients with CKD. Concerted efforts from all stakeholders are needed to overcome the barriers.

Temporal trends in prevalence and disability of chronic kidney disease caused by specific etiologies: an analysis of the Global Burden of Disease Study 2019

BACKGROUND

The prevalence of disability in CKD is high. In this context the aim of the present study was to assess the  temporal trends of prevalence and disability progression for chronic kidney disease (CKD) caused by specific etiologies.

METHODS

Using data from the Global Burden of Diseases Study (GBD) 2019, we examined the age-standardized rates of CKD prevalence and disability-adjusted life-years for different etiologies, including Type 1/2 diabetes mellitus (T1DM/T2DM), glomerulonephritis, and hypertension. We also calculated the average annual percentage changes to assess trends. Additionally, we utilized the joinpoint regression model to identify significant shifts over time.

RESULTS

From 1990 to 2019, the global prevalence of CKD due to various etiologies exhibited an overall increasing trend, albeit with fluctuations. Notably, CKD due to T1DM, glomerulonephritis, and hypertension consistently demonstrated a significant upward trend across all continents, while the prevalence of CKD due to T2DM varied across continents. In terms of disability-adjusted life-years, CKD due to T2DM and hypertension exhibited a significant rising trend over the past 30 years. However, changes in age standardized disability-adjusted life-years for CKD due to different etiologies were not consistent across continents, with an upward trend observed in The Americas and a contrasting trend in Asia. Furthermore, both age-standardized prevalence rate and age standardized disability-adjusted life-year trends for CKD varied significantly across 204 countries and territories. Additionally, a negative association was observed between the Socio-demographic Index and the disability progression of CKD.

CONCLUSION

The prevalence and disability burden of CKD caused by specific etiologies show substantial heterogeneity worldwide, highlighting significant disparities in the distribution of CKD. It is crucial to implement geographic and personalized strategies in different regions to alleviate the burden of CKD effectively.

[Chronic kidney disease in geriatrics]

Chronic kidney disease (CKD) affects almost 10% of the world's population, and over 30% of people aged over 70 [1,2]. The overall incidence of treated CKD is stable in France, but continues to rise sharply in people aged over 85 [3]. In its advanced stages, CKD is associated with numerous complications linked to disturbances in water, acid-base and phosphocalcium balance, as well as anemia and increased cardiovascular risk. A better understanding of risk factors, improved practices to promote nephroprotection, and progress in therapeutic education and preparation for suppletive techniques would help reduce this risk.

Presence and Onset of Chronic Kidney Disease as a Factor Involved in the Poor Prognosis of Patients with Essential Thrombocythemia

Chronic kidney disease (CKD) is an important risk factor for cardiovascular disease, thrombosis, and all-cause death. However, few studies have examined the association between CKD and the prognosis of patients with essential thrombocythemia (ET). We collected ET patients who met the WHO classification 2017 and performed a retrospective clinical study to clarify the association between the presence and onset of CKD and prognosis. Of 73 patients who met the diagnostic criteria, 21 (28.8%) had CKD at the time of ET diagnosis. The age of patients with CKD was significantly higher, and a high proportion of these patients had the JAK2V617F gene mutation. The presence of CKD was a risk factor for the prognosis (hazard ratio (HR): 3.750, 95% confidence interval (CI): 1.196-11.760, P=0.023), and the survival curve was significantly poorer. Furthermore, we analyzed patients without CKD at the time of ET diagnosis using the onset of CKD as a time-dependent variable and identified the onset of CKD as a risk factor for the prognosis (HR: 9.155, 95% CI: 1.542-54.370, P=0.005). In patients with renal hypofunction at the time of ET diagnosis or those with a reduction in the kidney function during follow-up, strict renal function monitoring at regular intervals is necessary.

BMAL1 inhibits renal fibrosis and renal interstitial inflammation by targeting the ERK1/2/ELK-1/Egr-1 axis

RATIONALE

Renal fibrosis and renal interstitial inflammation due to hydronephrosis are associated with progressive chronic kidney disease (CKD). The clock gene BMAL1 is thought to be involved in various diseases, including hypertension, diabetes, etc. However, little is known about how BMAL1 regulates renal fibrosis and renal interstitial inflammation in obstructed kidneys.

METHODS

The expression level of BMAL1 in UUO was examined using the GEO database. Lentivirus, siRNA and adeno-associated virus were used to modulate BMAL1 levels in HK-2 cells and mouse kidney. qRT-PCR, immunofluorescence staining, histological analysis, ELISA and Western blot were used to determine the level of fibrin deposition and the release of inflammatory factors. Immunofluorescence staining and western blotting were used to examine the interaction between BMAL1 and the ERK1/2/ELK-1/Egr-1 axis.

RESULTS

Bioinformatics analysis and in vivo experiments in this study showed that the expression level of BMAL1 in UUO model kidneys was higher than that in normal kidneys. We then found that downregulation of BMAL1 promoted the production of extracellular matrix (ECM) proteins and proinflammatory factors in vivo and in vitro, whereas upregulation inhibited this process. In addition, we demonstrated that the ERK1/2/ELK-1/Egr-1 axis is an important pathway for BMAL1 to play a regulatory role, and the use of PD98059 abolished the promoting effect of down-regulation of BMAL1 on fibrosis and inflammation.

CONCLUSIONS

Our findings suggest that BAML1 can target the ERK1/2/ELK-1/Egr-1 axis to suppress fibrotic progression and inflammatory events in obstructed kidneys, thereby inhibiting the development of CKD.

Causes of kidney failure among patients undergoing maintenance hemodialysis in Somalia: a multi-center study

BACKGROUND

Kidney failure is one of the leading causes of morbidity and mortality worldwide. The incidence of kidney failure in Somalia has been increasing in recent years. There is no data available on the causes of chronic kidney disease (CKD) leading to kidney failure in Somalia.

METHODS

This is a multicentre, descriptive cross-sectional study designed to determine the aetiology of kidney failure among patients receiving haemodialysis in four major demographic areas of Somalia. The study was conducted over a one-year period, from June 2021 to June 2022. Participants were eligible for inclusion if they had been diagnosed with kidney failure, were on regular haemodialysis, and were over 18 years of age.

RESULTS

A total of 127 patients were evaluated, 84 (66.1%) were males and 43 (33.9%) were female. The mean age of kidney failure patients was 49.3 ± 12.2 years. They originated from various regions, 5.6% from the south, 29.9% from the north-eastern, and 64.5% from the northwest. The mean duration of haemodialysis was 4.4 ± 2.2 years. The most common cause of kidney failure in our study was hypertension (33.1%), followed by diabetes mellitus (27.6%), uncertain aetiology (24.4%), glomerulonephritis (7.1%), obstructive uropathy (3.8%), renovascular hypertension (1.6%), neurogenic bladder, polycystic kidney disease, congenital and hereditary diseases (0.8%).

CONCLUSIONS

Our study showed the leading cause of kidney failure among maintenance haemodialysis patients was hypertension, followed by diabetes mellitus. To reduce the burden of kidney failure in Somalia, primary prevention of hypertension and diabetes and early detection and prompt management of chronic kidney disease (CKD) in high-risk populations should be a fundamental focus.

Catheter-Related Bloodstream Infections among patients on maintenance haemodialysis: a cross-sectional study at a tertiary hospital in Ghana

BACKGROUND

Catheter-Related Bloodstream Infections (CRBSIs) are notable complications among patients receiving maintenance haemodialysis. However, data on the prevalence of CRBSIs is lacking. This study was conducted to determine the prevalence and factors associated with CRBSIs among patients receiving haemodialysis in the renal unit of the largest tertiary hospital in Ghana.

METHODS

A hospital-based cross-sectional study was conducted on patients receiving maintenance haemodialysis via central venous catheters (CVC) between September 2021 and April 2022. Multivariate analysis using logistic regression was used to determine the risk factors that were predictive of CRBSI. Analysis was performed using SPSS version 23 and a p-value<0.05 was statistically significant.

RESULTS

The prevalence of CRBSI was 34.2% (52/152). Of these, more than half of them (53.9%(28/52)) had Possible CRBSI while 11.5% (6/52) had Definite CRBSI. Among the positive cultures, 62% (21/34) were from catheter sites whilst the rest were from peripheral blood. Gram-negative cultures made up 53% (18/34) of positive cultures with the rest being Gram positive cultures. Acinetobacter baumannii (33.3% (6/18)) was the commonest organism isolated among Gram-negative cultures whilst Coagulase negative Staphylococci (43.7% (7/16)) was the commonest organism isolated among Gram-positve cultures. Gram-negative bacilli were more predominant in this study making up 52.9% of the total bacteria cultured. Sex, duration of maintenance dialysis, underlying cause of End-stage kidney disease, mean corpuscular haemoglobin (MCH), neutrophil count and lymphocyte count were significantly predictive of CRBSI status (p<0.05).

CONCLUSION

There was a high prevalence of CRBSI among patients undergoing haemodialysis. The commonest causative agent was Coagulase negative Staphylococci, however there was a predominance of Gram-negative bacilli as compared to Gram positive cocci. There is a need to set up infection surveillance unit in the renal unit to track CRBSI and put in place measures to reduce these CRBSI.

Kidney fibrosis: Emerging diagnostic and therapeutic strategies

An increasing number of patients worldwide suffers from chronic kidney disease (CKD). CKD is accompanied by kidney fibrosis, which affects all compartments of the kidney, i.e., the glomeruli, tubulointerstitium, and vasculature. Fibrosis is the best predictor of progression of kidney diseases. Currently, there is no specific anti-fibrotic therapy for kidney patients and invasive renal biopsy remains the only option for specific detection and quantification of kidney fibrosis. Here we review emerging diagnostic approaches and potential therapeutic options for fibrosis. We discuss how translational research could help to establish fibrosis-specific endpoints for clinical trials, leading to improved patient stratification and potentially companion diagnostics, and facilitating and optimizing development of novel anti-fibrotic therapies for kidney patients.

Comparison of the Charlson comorbidity index, the modified Charlson comorbidity index, and the recipient risk score in prediction of the graft and patient survival among renal graft recipients: historical cohort in a single center

OBJECTIVE

To compare the predictive values of Charlson comorbidity index (CCI), modified Charlson comorbidity index kidney transplant (mCCI-KT) and recipient risk score (RRS) indices in prediction of patient and graft survival in kidney transplant patients.

METHODS

In this retrospective study, all patients who underwent a live-donor KT from 2006 to 2010, were included. Demographic data, comorbidities and survival time after KT were extracted and the association between above indices with patient and graft survival were compared.

RESULTS

In ROC curve analysis of 715 included patients, all three indicators were weak in predicting graft rejection with the area under curve (AUC) less than 0.6. The best models for predicting the overall survival were mCCI-KT and CCI with AUC of 0.827 and 0.780, respectively. Sensitivity and specificity of mCCI-KT at cut point of 1 were 87.2 and 75.6. Sensitivity and specificity of CCI at cut point of 3 were 84.6 and 68.3 and for RRS at cut point of 3 were 51.3 and 81.2, respectively.

CONCLUSION

The mCCI-KT index followed by the CCI index provided the best model in predicting the 10-year patient survival; however, they were poor in predicting graft survival and this model can be used for better stratifying transplant candidates prior to surgery.

Prevalence and Risk Factors of Chronic Kidney Disease in the General Population in Abidjan, Côte d'Ivoire: A Cross-sectional Study

Chronic kidney disease (CKD) is a major cause of morbidity and mortality worldwide, but few studies are available on CKD in Cote d'Ivoire. We aimed to assess the prevalence of CKD and identify its associated factors in the general population in Abidjan in 2016 in a cross-sectional study that included 1418 subjects. We did not receive laboratory data for 38 subjects, including serum creatinine data. Of the 1380 remaining subjects, 138 cases of CKD were included in the study (10% prevalence). We observed a female predominance (sex ratio = 0.81), and the mean age was 43.7 ± 14.5 years. Histories of hypertension (HTN) (29.7%) and diabetes (10.1%) were reported. The main clinical signs were high blood pressure (51.4%), obesity (21%), proteinuria (37.9%), and hematuria (37.4%). The glomerular filtration rate (GFR) was <60 mL/min in 8.2% of cases according to the Modification of Diet in Renal Disease equation, in 8.6% according to the CKD Epidemiology Collaboration equation, and in 12.6% according to the Cockroft-Gault (CG) equation. The other laboratory signs were hyperglycemia (51.4%), hypercholesterolemia (34.1%), and hyperlipidemia (21%). In the multivariate analysis, factors such as female sex (P = 0.013), age >55 years (P = 0.02), a history of HTN (P = 0.001), hypercholesterolemia (P = 0.010), and hyperlipidemia (P = 0.009) were associated with the risk of CKD. The prevalence of CKD was high in our study. The CG equation should not be used to estimate the GFR in the general population. Prevention involves managing modifiable risk factors.

Risk of End-Stage Renal Disease in Patients With Systemic Lupus Erythematosus and Diabetes Mellitus: A Danish Nationwide Cohort Study

OBJECTIVE

The risk of end-stage renal disease (ESRD) is increased in patients with systemic lupus erythematosus (SLE). This study was undertaken to determine whether diabetes mellitus (DM) increases ESRD risk in a large inception cohort of SLE patients.

METHODS

By means of the Danish National Patient Registry, we identified 3,178 adult patients diagnosed as having SLE between January 1, 1996, and July 31, 2018. DM was defined as the date of first hospital contact for DM or date of a first prescription of an antidiabetic drug. ESRD was defined as first registration of dialysis, renal transplant, or terminal renal insufficiency in the Danish National Patient Registry. ESRD incidence was compared between SLE patients with DM (SLE-DM) and those without DM (SLE-non-DM). Hazard ratios (HRs), adjusted for sex, age, educational level, and occupational status at baseline were calculated for sex, age, educational level, and hypertension (at baseline or during follow-up) strata. The overall hazard ratio (HR) was also adjusted for hypertension.

RESULTS

The SLE-DM group included 290 patients, of whom 77% were female, compared with 85% of the 2,859 patients in the SLE-non-DM group. SLE-DM patients had a 3 times higher risk of ESRD compared with SLE-non-DM patients (multivariable-adjusted HR 3.3 [95% confidence interval 1.8-6.1]). In stratified multivariable-adjusted analyses, DM increased the rate of ESRD in women and men, patients ≥50 years old at baseline, those with low educational level at baseline, and those with concomitant hypertension.

CONCLUSION

Our findings indicate that SLE patients with DM have a markedly higher risk of developing ESRD compared with SLE patients without DM.

Relationship between peritoneal solute transport and dialysate inflammatory markers in peritoneal dialysis patients: A cross-sectional study

BACKGROUND

The associated factors of peritoneal small solute transport was not fully understood. This research aimed to investigate the connection between dialysate inflammatory markers (e.g. macrophage migration inhibitory factor, MIF) in peritoneal dialysis (PD) effluent and peritoneal solute transport rate (PSTR) properties.

SUBJECTS AND DESIGN

A total of 80 stable PD patients in the First ShaoYang Hospital were enrolled in present study. Overnight PD effluent and serum inflammatory markers including MIF, MCP-1, VEGF, IL-6, TNFα and TGFβ were detected. Pearson correlation analysis and Logistic regression was performed to determine the risk factors for the increased PSTR.

RESULTS

A trend toward increased values of MIF, MCP-1 and IL-6 in PD effluent was observed in subjects with high PSTR when compared with those with low PSTR. The Pearson correlation test showed that D/P Cr exhibited positive correlations with dialysis effluent MIF (r=0.32, p=0.01), MCP-1 (r=0.47, p=0.01), IL-6 (r=0.48, p=0.01). Conversely, no significant correlation was found between D/P Cr and TGF-β (r=0.04, p=0.70), TNF-ɑ (r=0.22, p=0.05), VEGF (r=0.02, p=0.86) and serum inflammatory markers. In the unadjusted regression analysis, dialysis effluent MIF (OR 2.41), MCP-1 (OR 1.72), IL-6 (OR 1.55) were associated with high PSTR condition. Multivariate logistic regression analysis showed that the adjusted odds ratios (OR) of dialysis effluent MIF for high PSTR were 2.47 in all subjects (p=0.03).

CONCLUSION

Elevated MIF, MCP-1 and IL-6 levels in PD effluent were associated with increased PSTR. Elevated dialysis effluent MIF levels was an independent risk factor for high PSTR in subjects with PD treatment.

Interventions for improving health literacy in people with chronic kidney disease

BACKGROUND

Low health literacy affects 25% of people with chronic kidney disease (CKD) and is associated with increased morbidity and death. Improving health literacy is a recognised priority, but effective interventions are not clear.

OBJECTIVES

This review looked the benefits and harms of interventions for improving health literacy in people with CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 12 July 2022 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. We also searched MEDLINE (OVID) and EMBASE (OVID) for non-randomised studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and non-randomised studies that assessed interventions aimed at improving health literacy in people with CKD.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and performed risk of bias analysis. We classified studies as either interventions aimed at improving aspects of health literacy or interventions targeting a population of people with poor health literacy. The interventions were further sub-classified in terms of the type of intervention (educational, self-management training, or educational with self-management training). Results were expressed as mean difference (MD) or standardised mean difference (SMD) with 95% confidence intervals (CI) for continuous outcomes and risk ratios (RR) with 95% CI for dichotomous outcomes.

MAIN RESULTS

We identified 120 studies (21,149 participants) which aimed to improve health literacy. There were 107 RCTs and 13 non-randomised studies. No studies targeted low literacy populations. For the RCTs, selection bias was low or unclear in 94% of studies, performance bias was high in 86% of studies, detection bias was high in 86% of studies reporting subjective outcomes and low in 93% of studies reporting objective outcomes. Attrition and other biases were low or unclear in 86% and 78% of studies, respectively. Compared to usual care, low certainty evidence showed educational interventions may increase kidney-related knowledge (14 RCTs, 2632 participants: SMD 0.99, 95% CI 0.69 to 1.32; I² = 94%). Data for self-care, self-efficacy, quality of life (QoL), death, estimated glomerular filtration rate (eGFR) and hospitalisations could not be pooled or was not reported. Compared to usual care, low-certainty evidence showed self-management interventions may improve self-efficacy (5 RCTs, 417 participants: SMD 0.58, 95% CI 0.13 to 1.03; I² = 74%) and QoL physical component score (3 RCTs, 131 participants: MD 4.02, 95% CI 1.09 to 6.94; I² = 0%). There was moderate-certainty evidence that self-management interventions probably did not slow the decline in eGFR after one year (3 RCTs, 855 participants: MD 1.53 mL/min/1.73 m², 95% CI -1.41 to 4.46; I² = 33%). Data for knowledge, self-care behaviour, death and hospitalisations could not be pooled or was not reported. Compared to usual care, low-certainty evidence showed educational with self-management interventions may increase knowledge (15 RCTs, 2185 participants: SMD 0.65, 95% CI 0.36 to 0.93; I² = 90%), improve self-care behaviour scores (4 RCTs, 913 participants: SMD 0.91, 95% CI 0.00 to 1.82; I² =97%), self-efficacy (8 RCTs, 687 participants: SMD 0.50, 95% CI 0.10 to 0.89; I² = 82%), improve QoL physical component score (3 RCTs, 2771 participants: MD 2.56, 95% CI 1.73 to 3.38; I² = 0%) and may make little or no difference to slowing the decline of eGFR (4 RCTs, 618 participants: MD 4.28 mL/min/1.73 m², 95% CI -0.03 to 8.85; I² = 43%). Moderate-certainty evidence shows educational with self-management interventions probably decreases the risk of death (any cause) (4 RCTs, 2801 participants: RR 0.73, 95% CI 0.53 to 1.02; I² = 0%). Data for hospitalisation could not be pooled.

AUTHORS' CONCLUSIONS

Interventions to improve aspects of health literacy are a very broad category, including educational interventions, self-management interventions and educational with self-management interventions. Overall, this type of health literacy intervention is probably beneficial in this cohort however, due to methodological limitations and high heterogeneity in interventions and outcomes, the evidence is of low certainty.

Estimated glomerular filtration rate trajectories in south Asians: Findings from the cardiometabolic risk reduction in south Asia study

Background

Few longitudinal data characterize kidney function decline among South Asians, one of the world's largest population groups. We aimed to identify estimated glomerular filtration rate (eGFR) trajectories in a population-based cohort from India and assess predictors of rapid kidney function decline.

Methods

We used 6-year longitudinal data from participants of a population-representative study from Delhi and Chennai, India who had at least two serum creatinine measures and baseline CKD-EPI eGFR> 60 ml/min/1.73m² (n=7779). We used latent class trajectory modeling to identify patterns of kidney function trajectory (CKD-EPI eGFR) over time. In models accounting for age, sex, education, and city, we tested the association between 15 hypothesized risk factors and rapid kidney function decline.

Findings

Baseline mean eGFR was 108 (SD 16); median eGFR was 110 [IQR: 99-119] ml/min/1.73m². Latent class trajectory modeling and functional characterization identified three distinct patterns of eGFR: class-1 (no decline; 58%) annual eGFR change 0.2 [0.1, 0.3]; class-2 (slow decline; 40%) annual eGFR change -0.2 [-0.4, -0.1], and class-3 (rapid decline; 2%) annual eGFR change -2.7 [-3.4, -2.0] ml/min/1.73m². Albuminuria (>30 mg/g) was associated with rapid eGFR decline (OR for class-3 vs class-1: 5.1 [95% CI: 3.2; 7.9]; class-3 vs. class-2: 4.3 [95% CI:2.7; 6.6]). Other risk factors including self-reported diabetes, cardiovascular disease, peripheral arterial disease, and metabolic biomarkers such as HbA1c and systolic blood pressure were associated with rapid eGFR decline phenotype but potential 'non-traditional' risk factors such as manual labor or household water sources were not.

Interpretation

Although mean and median eGFRs in our population-based cohort were higher than those reported in European cohorts, we found that a sizeable number of adults residing in urban India are experiencing rapid kidney function decline. Early and aggressive risk modification among persons with albuminuria could improve kidney health among South Asians.

Funding

The CARRS study has been funded with federal funds from the National Heart, Lung, and Blood Institute, National Institutes of Health, under Contract No. HHSN2682009900026C and P01HL154996. Dr. Anand was supported by NIDDK K23DK101826 and R01DK127138.

Cost-Effectiveness of Dapagliflozin for Non-diabetic Chronic Kidney Disease

BACKGROUND

In the USA, chronic kidney disease (CKD) affects 1 in 7 adults and costs $100 billion annually. The DAPA-CKD trial found dapagliflozin, a sodium glucose co-transporter 2 (SGLT2) inhibitor, to be effective in reducing CKD progression and mortality in patients with diabetic and non-diabetic CKD. Currently, SGLT2 inhibitors are not considered standard of care for patients with non-diabetic CKD.

OBJECTIVE

Determine the cost-effectiveness of adding dapagliflozin to standard management of patients with non-diabetic CKD.

DESIGN

Markov model with lifetime time horizon and US healthcare sector perspective.

PATIENTS

Patients with non-diabetic CKD INTERVENTION: Dapagliflozin plus standard care versus standard care only.

MAIN MEASURES

Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs), all discounted at 3% annually; total incidence of kidney failure on kidney replacement therapy; average years on kidney replacement therapy.

KEY RESULTS

Adding dapagliflozin to standard care improved life expectancy by 2 years, increased discounted QALYS (from 6.75 to 8.06), and reduced the total incidence of kidney failure on kidney replacement therapy (KRT) (from 17.4 to 11.0%) and average years on KRT (from 0.77 to 0.43) over the lifetime of the cohort. Dapagliflozin plus standard care was more effective than standard care alone while increasing lifetime costs (from $245,900 to $324,8900, or $60,000 per QALY gained). Results were robust to variations in assumptions about dapagliflozin's efficacy over time and by CKD stage, added costs of kidney replacement therapy, and expected population annual CKD progression rates and sensitive to the cost of dapagliflozin. The net 1-year budgetary implication of treating all US patients with non-diabetic CKD could be up to $21 billion.

CONCLUSIONS

Dapagliflozin improved life expectancy and reduced progression of CKD, the proportion of patients requiring kidney replacement therapy, and time on kidney replacement therapy in patients with non-diabetic CKD. Use of dapagliflozin meets conventional criteria for cost-effectiveness.

Clinical and Prognostic Implications of Estimating Glomerular Filtration Rate by Three Different Creatinine-Based Equations in Older Nursing Home Residents

Background

According to the international literature, the percentage of nursing home (NH) residents with renal insufficiency is very high, ranging between 22 and 78%. Diminished kidney function represents a risk factor for drug overdosage, adverse drug reactions, end-stage renal disease, disability, morbidity, and mortality. Several studies suggested that screening for chronic kidney disease (CKD) in high-risk and older populations may represent a cost-effective approach to reducing progression to renal failure and CKD mortality.

Objective

This study aimed (i) to investigate to what extent CKD may be staged interchangeably by three different creatinine-based estimated glomerular filtration rate (eGFR) equations in a sample of older adults living in long-term care facilities; (ii) to investigate factors explaining differences among eGFR equations; and (iii) to compare the predictivity of different creatinine-based eGFR equations with respect to all-cause mortality.

Methods

A total of 522 residents aged 65 years and older participated in a prospective cohort study of 9 long-term care facilities in Calabria. eGFR was calculated by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Berlin initiative study (BIS), and full age spectrum (FAS) equations. Disability in at least one activity of daily living (ADL), depression, cognitive impairment, comorbidity, and malnutrition was considered in the analysis. Statistical analysis was carried out by Bland-Altman analysis, and 2-year mortality was investigated by Kaplan-Meier curves and Cox regression analysis.

Results

Depending on the adopted equation, the prevalence of NH residents with impaired renal function (eGFR < 60 ml/min/1.73 m²) ranged between 58.2% for the CKD-EPI and 79.1% for the BIS1 equation. The average difference between BIS and FAS was nearly negligible (0.45 ml/min/1.73 m²), while a significant bias was detected between CKD-EPI and BIS and also between CKD-EPI and FAS (6.21 ml/min/1.73 m² and 6.65 ml/min/1.73 m², respectively). Although the eGFR study equations had comparable prognostic accuracy in terms of mortality risk, BIS and FAS were able to reclassify NH residents pertaining to a low-risk group with CKD-EPI, and this reclassification improves the discriminative capacity of CKD-EPI with respect to overall mortality.

Conclusion

Despite the relatively good correlation between eGFRs calculated using all adopted equations, the findings in this study reported clearly demonstrated that CKD-EPI and BIS/FAS equations are not interchangeable to assess eGFR among older people and particularly in institutionalized and frail older subjects.

Identification of Important Modules and Hub Gene in Chronic Kidney Disease Based on WGCNA

Chronic kidney disease (CKD) is an ongoing deterioration of renal function that often progresses to end-stage renal disease. In this study, we aimed to screen and identify potential key genes for CKD using the weighted gene coexpression network (WGCNA) analysis tool. Gene expression data related to CKD were screened from GEO database, and expression datasets of GSE66494 and GSE62792 were obtained. After discrete analysis of samples, WGCNA analysis was performed to construct gene coexpression module, and the correlation between the module and disease was calculated. The modules with a significant correlation with the disease were selected for Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Then, the interaction network of related molecules was constructed, and the high score subnetwork was selected, and the candidate key molecules were identified. A total of 882 DEGs were identified in the screening datasets. A subnetwork containing 6 nodes was found with a high score of 12.08, including CEBPZ, IFI16, LYAR, BRIX1, BMS1, and DDX18. DEGs could significantly differentiate CKD and healthy individuals in principal component analysis. In addition, the MEturquiose, MEred, and MEblue in group were significantly correlated with disease in WGCNA. These 6 hub genes were found to significantly discriminate between CKD and healthy controls in the validation dataset, suggesting that they could use these molecules as candidate markers to distinguish CKD from healthy people. Overall, our study indicated that 6 hub genes may play key roles in the occurrence and development of CKD.

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.

Comparing prevalence of chronic kidney disease and its risk factors between population-based surveys in Russia and Norway

Background

Little data exists on the prevalence of chronic kidney disease (CKD) in the Russian population. We aimed to estimate the prevalence of CKD in a population-based study in Russia, compare with a similar study in Norway, and investigate whether differences in risk factors explained between-study differences in CKD.

Methods

We compared age- and sex-standardised prevalence of reduced eGFR (< 60 ml/min/1.73m² CKD-EPI creatinine equation), albuminuria and or a composite indicator of CKD (one measure of either reduced eGFR or albuminuria) between participants aged 40–69 in the population-based Know Your Heart (KYH) study, Russia (2015–2018 N = 4607) and the seventh Tromsø Study (Tromsø7), Norway (2015–2016 N = 17,646). We assessed the contribution of established CKD risk factors (low education, diabetes, hypertension, antihypertensive use, smoking, obesity) to between-study differences using logistic regression.

Results

Prevalence of reduced eGFR or albuminuria was 6.5% (95% Confidence Interval (CI) 5.4, 7.7) in KYH and 4.6% (95% CI 4.0, 5.2) in Tromsø7 standardised for sex and age. Odds of both clinical outcomes were higher in KYH than Tromsø7 (reduced eGFR OR 2.06 95% CI 1.67, 2.54; albuminuria OR 1.54 95% CI 1.16, 2.03) adjusted for sex and age. Risk factor adjustment explained the observed between-study difference in albuminuria (OR 0.92 95% CI 0.68, 1.25) but only partially reduced eGFR (OR 1.42 95% CI 1.11, 1.82). The strongest explanatory factors for the between-study difference was higher use of antihypertensives (Russian sample) for reduced eGFR and mean diastolic blood pressure for albuminuria.

Conclusions

We found evidence of a higher burden of CKD within the sample from the population in Arkhangelsk and Novosibirsk compared to Tromsø, partly explained by between-study population differences in established risk factors. In particular hypertension defined by medication use was an important factor associated with the higher CKD prevalence in the Russian sample.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02738-2.

Factors associated with quitting status of smoking in Korean men with and without chronic kidney disease: A national population-based study

INTRODUCTION

Adverse effects of smoking on kidney function have been demonstrated in both general populations and in populations with chronic kidney disease (CKD). Therefore, quitting smoking can have a significant impact on the mortality and disease progression of CKD. This study examined and compared factors associated with quitting status of smoking, in patients with and without CKD, among Korean adult male smokers, using the Korea National Health and Nutrition Examination Survey from 2008 to 2019, excluding 2013.

METHODS

Wald test with multiple logistic regression was performed to investigate factors associated with quitting smoking in both CKD and non-CKD groups, along with the interaction effects between groups.

RESULTS

Of the 15747 eligible individuals, 909 had CKD, of whom 703 (weighted percentage: 74.4%) were quitters. In the non-CKD group, 8393 (weighted percentage: 50.4%) succeeded in quitting. Regular exercise was the only factor associated with quitting in both groups. The adjusted odd ratios with confidence intervals were 1.29 (95% CI: 1.17–1.42) and 2.84 (95% CI: 1.52–5.31) in the non-CKD and CKD groups, respectively (interaction p=0.0153). Unlike in the CKD group, marriage and higher systolic blood pressure were also associated with quitting, and lifetime smoking amount and secondhand smoke exposure at home were negatively associated with smoking cessation in the non-CKD group.

CONCLUSIONS

Exercise was the only factor associated with quitting smoking in the CKD group.

Direction- and Angle-Assisted Buttonhole Cannulation of Arteriovenous Fistula in Hemodialysis Patients: A Multicenter Randomized Controlled Trial

RATIONALE & OBJECTIVE

Arteriovenous fistula cannulation with the buttonhole technique is often preferred by patients but has been associated with an increased infection risk. Guidelines disagree on whether it should be abandoned, thus we assessed a technologically simple method to facilitate gentler arteriovenous fistula cannulation with potentially less discomfort and damage to the epithelial lining of the buttonhole tract.

STUDY DESIGN

8-week, prospective, open-label, randomized controlled trial.

SETTING & PARTICIPANTS

Patients with buttonhole tracts receiving hemodialysis at 7 dialysis centers in Norway were randomized to the intervention group (43 patients, 658 cannulations) or control group (40 patients, 611 cannulations).

INTERVENTION

Direction and angle of the established buttonhole tract were marked on the forearm skin in the intervention group, whereas the control group had no structured cannulation information system.

OUTCOMES

The primary outcome was successful cannulation, defined as correct placement of both blunt needles at the first attempt without needing to change needles, perform extra perforations, or reposition the needle. The secondary outcomes were patient-reported difficulty of cannulation (verbal rating scale: 1 = very easy, 6 = impossible) and intensity of pain (numeric rating scale: 0 = no pain, 10 = unbearable pain).

RESULTS

After a 2-week run-in period, successful cannulation was achieved in 73.9% and 74.8% of the patients in the intervention and control groups, respectively (relative risk [RR], 0.99; 95% CI, 0.87-1.12; P = 0.85). However, the probability of a difficult arterial cannulation (verbal rating scale, 3-6) was significantly lower in the intervention group (RR, 0.69; 95% CI, 0.55-0.85; P = 0.001). There were no improvements for venous cannulations. Furthermore, the probability of a painful cannulation (numeric rating scale, 3-10) was lower in the intervention group (RR, 0.72; 95% CI, 0.51-1.02; P = 0.06).

LIMITATIONS

Unable to evaluate hard end points such as infections and thrombosis owing to the small sample size.

CONCLUSIONS

Marking direction and angle of cannulation did not improve cannulation success rates; however, patients more often reported an unproblematic procedure and less pain.

FUNDING

None.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01536548).

[Prevalence of chronic kidney disease in Antananarivo, Madagascar]

INTRODUCTION

Chronic kidney disease is defined as an inability of the kidney to perform its normal functions and which persists beyond three months. Nowadays, the estimated glomerular filtration rate based on plasmatic creatinine level remains the gold standard to assess renal function. In Madagascar, we miss national data concerning the epidemiology of chronic kidney disease probably due to the complexity of carrying out the serum creatinine assays. The recent availability of creatinometer using a creatinine strip test with capillary creatinine facilitated the determination of the creatinine level in epidemiological study.

PATIENTS AND METHODS

This simple technique allowed us to plan a pilot study in Antananarivo, the capital of Madagascar. The main objective was to assess the prevalence of chronic kidney disease determined from capillary creatinine level. The secondary objective was to determine the factors associated with chronic kidney disease in Madagascar. It is an analytical cross-sectional study over a period of three months. Chronic kidney disease is defined as a decrease of the glomerular filtration rate of capillary creatinine less than 60mL/min/1.73m² and calculated with Chronic Kidney Disease Epidemiology formula (CKD-EPI). The minimum number of studied population has been assessed and settled at 210 people. Cluster sampling was performed for randomization of participants.

RESULTS

At the end of the study, 210 people were randomized for screening. The average age was 40 years old with 14.9 as standard deviation. The sex ratio (male/female) was 1.76. The prevalence of chronic kidney disease was 13.8% with extreme values of 9,1 and 18.5. With chronic kidney disease, high blood pressure (hypertension) and diabetes were found respectively in 41.3 and 17.2%. Chronic kidney disease affected mainly in 72.4% of population aged 25 to 54 years old.

CONCLUSION

This is the first study in Africa to screen chronic kidney disease using a creatinine strip test. This prevalence is relatively different compared to other African countries. The limits of the study are the absence of a subsequent control and/or double control of the creatinine, which definitively confirms the chronicity of kidney disease, the absence evaluation of the urinary sediments to determine proteinuria. Nevertheless, the results of our study can be used as data awaiting the results of a multicenter studies. To determine the national prevalence of chronic kidney disease, screening in the six provinces is currently in progress.

Sex Differences in Fecal Microbiota Correlation With Physiological and Biochemical Indices Associated With End-Stage Renal Disease Caused by Immunoglobulin a Nephropathy or Diabetes

This study investigated the sex-specific differences in the correlation between intestinal microbiota and end-stage renal disease. Here, we compared the differences in the gut microbiota of male and female healthy controls (HC) and patients with end-stage renal disease (ESRD) caused by immunoglobulin A (IgA) nephropathy (ESRD-IgAN) or type-2 diabetes mellitus (ESRD-T2DM) using high-throughput sequencing of the 16S rRNA gene. We also analyzed the correlation between gut microbiota and clinical immune indicators. We assigned 8, 10, 5, 7, 11, and 20 volunteers to female HC, ESRD-IgAN, and ESRD-T2DM, and male HC, ESRD-IgAN, and ESRD-T2DM, respectively. The results showed sex-specific differences in both physiological and biochemical indices and intestinal microbiota composition, as well as the correlation between them. The correlations between physiological and biochemical indices in men were significantly lower than those in women, especially for indices related to immunity, blood glucose, and cardiac color sonography. Urine output, lymphocyte ratio, serum albumin, blood calcium, dialysis status, serum urea nitrogen, urine protein, and diabetes significantly correlated with male fecal microbiota composition, whereas only creatinine and 2-h post-prandial blood glucose significantly correlated with female fecal microbiota composition. The top 50 dominant operational taxonomic units showed a stronger correlation with physiological and biochemical indices in samples obtained from females than from males. These differences highlight sex-specific differences in the effectiveness of ESRD prevention and treatments via regulating intestinal microbiota.

Prognostic value of beta-2 microglobulin on mortality in chronic kidney disease patients: A systematic review and meta-analysis

The aim of this study was to delve into whether beta-2 microglobulin could assess all-cause mortality in patients with chronic kidney disease. PubMed and Embase were systematically searched. Hazard risk and 95% CI were pooled using random-effect models. A total of eight studies were involved according to the inclusion and exclusion criterions. By meta-analysis, each 1 mg/L increase in beta-2 microglobulin displayed positive relationships to the risk of all-cause mortality (hazard risk 1.03, 95% CI = 1.02-1.03) and cardiovascular events (hazard risk 1.04, 95% CI = 1.00-1.08) in patients with dialysis. However, the relationship between elevated level of serum beta-2 microglobulin as a categorical variable and mortality was not significant. The prognostic value of elevated beta-2 microglobulin might be significant in ESRD patients with dialysis and a proper cutoff value to predict mortality should be determined in the future.

Specific alterations in gut microbiota in patients with chronic kidney disease: an updated systematic review

BACKGROUND

Emerging evidence demonstrates that gut dysbiosis is implicated in the pathogenesis of chronic kidney disease (CKD) with underlying mechanisms involving mucosal and/or systematic immunity or metabolic disorders. However, the profile of gut microbiota in patients with CKD has not been completely explored.

METHODS

Databases from their date of inception to 31 March 2020 were systematically searched for case-control or cross-sectional studies comparing the gut microbial profiles in adult patients with CKD or end-stage renal disease (ESRD) with those in healthy controls. Quantitative analysis of alterations in gut microbial profiles was conducted.

RESULTS

Twenty-five studies with a total of 1436 CKD patients and 918 healthy controls were included. The present study supports the increased abundance of, phylum Proteobacteria and Fusobacteria, genus Escherichia_Shigella, Desulfovibrio, and Streptococcus, while lower abundance of genus Roseburia, Faecalibacterium, Pyramidobacter, Prevotellaceae_UCG-001, and Prevotella_9 in patients with CKD; and increased abundance of phylum Proteobacteria, and genus Streptococcus and Fusobacterium, while lower abundance of Prevotella, Coprococcus, Megamonas, and Faecalibacterium in patients with ESRD. Moreover, higher concentrations of trimethylamine-N-oxide and p-cresyl sulfate and lower concentrations of short-chain fatty acids were observed. Gut permeability in patients with CKD was not determined due to the heterogeneity of selected parameters.

CONCLUSIONS

Specific alterations of gut microbial parameters in patients with CKD were identified. However, a full picture of the gut microbiota could not be drawn from the data due to the differences in methodology, and qualitative and incomplete reporting of different studies.

Uraemic Cardiomyopathy in Different Mouse Models

Uraemic cardiomyopathy (UCM) is one of the most common complications in chronic kidney disease (CKD). Our aim was to compare characteristics of various UCM mouse models. Mice were assigned to the following groups: the pole ligation group, 5/6 nephrectomy group (5/6Nx), uninephrectomy plus contralateral ischemia followed by reperfusion group (IR), adenine group, and sham group. Mice were sacrificed at 4, 8, and 16 weeks after surgery in the pole ligation, 5/6Nx, and IR groups, respectively. In the adenine group, mice were sacrificed at 16 weeks after the adenine diet. The structure and function of the heart and the expression of fibroblast growth factor 23 (FGF-23) and growth differentiation factor 15 (GDF-15) in hearts were assessed. The mortality in the 5/6 Nx group was significantly higher than that in the pole ligation, IR, and adenine groups. Echocardiogram and histological examination showed cardiac hypertrophy in the adenine,5/6Nx, ligation group, and IR group. In addition, cardiac fibrosis occurred in all CKD modeling groups. Interestingly, cardiac fibrosis was more serious in the IR and adenine groups. FGF-23 expression in sham mice was similar to that in modeling groups; however, the GDF-15 level was decreased in modeling groups. Our results suggest that the four models of UCM show different phenotypical features, molding time and mortality. GDF-15 expression in the hearts of UCM mice was downregulated compared with sham group mice.

Estimated Glomerular Filtration Rate (eGFR) based on cystatin C was associated with increased risk of hip and proximal humerus fractures in women and decreased risk of hip fracture in men, whereas eGFR based on creatinine was not associated with fracture risk in both sexes: The Tromsø Study

PURPOSE

Patients with end-stage kidney disease have an increased fracture risk. Whether mild to moderate reductions in kidney function is associated with increased fracture risk is uncertain. Results from previous studies may be confounded by muscle mass because of the use of creatinine-based estimates of the glomerular filtration rate (eGFRcre). We tested the hypothesis that lower eGFR within the normal range of kidney function based on serum cystatin C (eGFRcys) or both cystatin C and creatinine (eGFRcrecys) predict fractures better than eGFR based on creatinine (eGFRcre).

METHODS

In the Tromsø Study 1994-95, a cohort of 3016 women and 2836 men aged 50-84 years had eGFRcre, eGFRcys and eGFRcrecys estimated using the Chronic Kidney Disease Epidemiology Collaboration equations. Hazard ratios (HRs) (95% confidence intervals) for fracture were calculated in Cox's proportional hazards models and adjusted for age, height, body mass index, bone mineral density, diastolic blood pressure, smoking, physical activity, previous fracture, diabetes and cardiovascular disease.

RESULTS

During a median of 14.6 years follow-up, 232, 135 and 394 women and 118, 35 and 65 men suffered incident hip, proximal humerus and wrist fractures. In women, lower eGFRcre did not predict fracture, but the risk for hip and proximal humerus fracture increased per standard deviation (SD) lower eGFRcys (HRs 1.36 (1.16-1.60) and 1.33 (1.08-1.63)) and per SD lower eGFRcrecys (HRs 1.25 (1.08-1.45) and 1.30 (1.07-1.57)). In men, none of the eGFR estimates were related to increased fracture risk. In contrast, eGFRcys and eGFRcrecys were inversely associated with hip fracture risk (HRs 0.85 (0.73-0.99) and 0.82 (0.68-0.98)).

CONCLUSIONS

In women, each SD lower eGFRcys and eGFRcrecys increased the risk of hip and proximal humerus fracture by 25-36%, whereas eGFRcre did not. In men, none of the estimates of eGFR were related to increased fracture risk, and each SD lower eGFRcys and eGFRcrecys decreased the risk of hip fracture by 15-18%. The findings particularly apply to a cohort of generally healthy individuals with a normal kidney function. In future studies, the association of measured GFR using the gold standard method of iohexol clearance with fractures risk should be examined for causal inference. More clinical research is needed before robust clinical inferences can be made.

Analysis of chronic kidney disease among national hospitalization data with 14 million children

BACKGROUND

The main purpose was to determine basic epidemiological data on CKD among hospitalized pediatric patients in China.

METHODS

Data from pediatric inpatients with CKD hospitalized from June 1, 2013 to May 31, 2017 were extracted from the electronic records of HQMS database, which includes over 14 million inpatients. Codes from the 10th revision of the International Classification of Diseases (ICD-10) were used to search the database.

RESULTS

A total of 524 primary diseases of CKD were included in this study. In all, there were 278 231 pediatric inpatients with CKD, which accounted for 1.95 % of the 14 250 594 pediatric inpatients registered in the HQMS database. The number of pediatric inpatients with CKD was 67 498 in 2013, 76 810 in 2014, 81 665 in 2015 and 82 649 in 2016, which accounted for 1.93 %, 1.93 %, 1.99 and 2.09 %, respectively, of the total population of pediatric inpatients. The etiology of CKD was secondary nephrosis in 37.95 % of cases, which ranked first and followed by CAKUT with a percentage of 24.61 %. Glomerular diseases and cystic kidney disease accounted for 21.18 and 5.07 %, respectively. Among all 278 231 patients, 6 581 (2.37 %) had a primary discharge diagnosis of CKD. The renal pathology findings of CKD showed that IgA accounted for 51.17 %.

CONCLUSIONS

This study provides a descriptive analysis of the hospitalized population of pediatric CKD patients. Our study provides important, fundamental data for policy making and legislation, registry implementation and the diagnosis, treatment and prevention of CKD in China.

Efficacy of statins on renal function in patients with chronic kidney disease: a systematic review and meta-analysis

Background

Studies have shown that the use of statins could significantly improve lipid profiles; however, it remains controversial whether the use of statins could improve renal function in patients with chronic kidney disease (CKD). Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of statins on renal function in patients with CKD.

Methods

We systematically searched PubMed, EMBASE, and the Cochrane Library databases for eligible RCTs from inception to October 2020. Pooled effect estimates were assigned as weighted mean differences (WMDs) with 95% confidence intervals (CIs) using the random-effects model.

Results

We selected 33 RCTs that recruited 37,391 patients with CKD patients. The summary results suggested that statin use significantly reduced urinary albumin (WMD: −2.04; 95%CI: −3.53 to −0.56; p = .007) and protein (WMD: −0.58; 95%CI: −0.95 to −0.21; p = .002) excretions and increased creatinine clearance (WMD: 0.86; 95%CI: 0.32–1.41; p = .002). However, there were no significant differences between statin and control groups in terms of changes in estimated glomerular filtration rate (WMD: 0.38; 95%CI: −0.04 to 0.79; p = .075), and serum creatinine levels (WMD: −0.07; 95%CI: −0.25, 0.12; p = .475).

Conclusions

We found that statin use in patients with CKD may slow CKD progression by lowering urinary albumin and protein excretions or increasing creatinine clearance. Further large-scale RCTs should be conducted to evaluate the long-term effects of statins on renal outcomes. Abbreviations: CKD: chronic kidney disease; RCT: randomized controlled trials; WMD: weighted mean differences; CI: confidence intervals; ACEI: angiotensin-converting enzyme inhibitors; eGFR: estimated glomerular filtration rate

Identifying Clinical and Genomic Features Associated With Chronic Kidney Disease

We apply a pattern-based classification method to identify clinical and genomic features associated with the progression of Chronic Kidney disease (CKD). We analyze the African-American Study of Chronic Kidney disease with Hypertension dataset and construct a decision-tree classification model, consisting 15 combinatorial patterns of clinical features and single nucleotide polymorphisms (SNPs), seven of which are associated with slow progression and eight with rapid progression of renal disease among African-American Study of Chronic Kidney patients. We identify four clinical features and two SNPs that can accurately predict CKD progression. Clinical and genomic features identified in our experiments may be used in a future study to develop new therapeutic interventions for CKD patients.

Ensuring the need is met: A 50-year simulation study of the National Kidney Registry's family voucher program

The National Kidney Registry (NKR) Advanced Donation Program enables living donors the opportunity to donate altruistically, or in advance of a potential recipient's transplant, and to receive a voucher that can be redeemed for a future transplant facilitated by the NKR. Family vouchers allow a donor to identify multiple individuals within their immediate family, with the first person in that group in need of a transplant being prioritized to receive a kidney. An increase in vouchers introduces concerns that demand for future voucher redemptions could exceed the supply of available donors and kidneys. A Monte Carlo simulation model was constructed to estimate the annual number of voucher redemptions relative to the number of kidneys available over a 50-year time horizon under several projected scenarios for growth of the program. In all simulated scenarios, the number of available kidneys exceeded voucher redemptions every year. While not able to account for all real-life scenarios, this simulation study found that the NKR should be able to satisfy the likely redemption of increasing numbers of vouchers under a range of possible scenarios over a 50-year time horizon. This modeling exercise suggests that a donor family's future needs can be satisfied through the voucher program.

The novel fibrosis index at diagnosis may predict all-cause mortality in patients with antineutrophil cytoplasmic antibody-associated vasculitis without substantial liver diseases

OBJECTIVES

Antineutrophil cyto plasmic antibody-associated vasculitis (AAV) is a fatal disease. Currently, predictors of mortality due to AAV are based on the distribution of organ involvement. The novel fibrosis index (NFI) is an index composed of laboratory results that reflect the degree of liver fibrosis. This study aimed to evaluate whether NFI can predict poor outcomes in patients with AAV without substantial liver disease.

METHODS

A total of 210 patients with immunosuppressive drug-naïve AAV were retrospectively reviewed. NFI was calculated as follows: NFI=(serum bilirubin × (alkaline phosphatase)2)/(platelet count×(serum albumin)2). NFI cut-off was set at 1.24 (the highest quartile). Poor outcomes were defined as all-cause mortality, relapse, and end-stage renal disease (ESRD).

RESULTS

During the median 34.5 months of follow-up, 21 patients (10%) died, 72 patients (34.3%) relapsed, and 38 patients (18.1%) had ESRD due to AAV progression. The median calculated NFI was 0.61, and it was higher in AAV patients with all-cause mortality than in those without mortality, but the difference was not statistically significant (1.26 vs. 0.59). AAV patients with NFI at diagnosis ≥1.24 exhibited a significantly lower cumulative patient survival rate than those with NFI at diagnosis <1.24 (p=0.002). Multivariate Cox hazard model analysis showed that NFI at diagnosis ≥1.24 was an independent predictor of all-cause mortality in AAV (hazard ratios [HR] 2.850, 95% confidence interval [CI] 1.026, 7.910).

CONCLUSIONS

NFI ≥1.24, which may be an independent predictive marker for all-cause mortality in AAV patients without substantial liver disease.

Hypertensive nephrosclerosis: wider kidney biopsy indications may be needed to improve diagnostics

BACKGROUND

Hypertensive nephrosclerosis is the presumed underlying cause in many end-stage kidney disease (ESKD) patients, but the diagnosis is disputed and based on clinical criteria with low diagnostic accuracy.

OBJECTIVE

To evaluate and improve the diagnostic process for nephrosclerosis patients.

METHODS

We included adults from the population-based HUNT study (n = 50 552), Norwegian CKD patients referred for kidney biopsy 1988-2012 (n = 7261), and unselected nephrology clinic patients (n = 193) used for matching. Decision tree analysis and ROC curve-based methods of optimal cut-offs were used to improve clinical nephrosclerosis criteria.

RESULTS

Nephrosclerosis prevalence was 2.7% in the general population, and eGFR decline and risk for kidney-related hospital admissions and ESKD were comparable to patients with diabetic kidney disease. In the biopsy cohort, current clinical criteria had very low sensitivity (0.13) but high specificity (0.94) for biopsy-verified arterionephrosclerosis. A new optimized diagnostic algorithm based on proteinuria (<0.75 g d^-1 ), systolic blood pressure (>155 mm Hg) and age (>75 years) only marginally improved diagnostic accuracy (sensitivity 0.19, specificity 0.96). Likewise, there were still false-positive cases with treatable diagnoses like glomerulonephritis, interstitial nephritis and others (40% of all test positive). Decision curve analysis showed that the new criteria can lead to higher clinical utility, especially for patients considering the potential harms to be close to the potential benefits, while the more risk-tolerant ones (harm:benefit ratio < 1:4) should consider kidney biopsy.

CONCLUSION

Further improvements of the current clinical criteria seem difficult, so risks and benefits of kidney biopsy could be more actively discussed with selected patients to reduce misclassification and direct treatment.

Worldwide Disparity in the Relation Between CKD Prevalence and Kidney Failure Risk

Introduction

The incidence of kidney replacement therapy (KRT) for kidney failure varies internationally much more than chronic kidney disease (CKD) prevalence. This ecologic study investigated the relation of CKD prevalence to KRT and mortality risks by world region.

Methods

We used data from Global Burden of Disease and KRT registries worldwide with linear models to estimate the percentages of variance in KRT incidence and all-cause mortality explained by age-adjusted prevalence of CKD stages 3 to 5, overall and by gender, in 61 countries classified in 3 regions: high income (n = 28), Eastern and Central Europe (n = 15), and other (n = 18).

Results

The incidence of KRT ranged from 89 to 378 per million population in high-income regions, 32 to 222 per million population in Central and Eastern Europe, and 22 to 493 per million population in the other region; age-adjusted CKD prevalence ranged from 5.5% to 10.4%, 7.6% to 13.7%, and 7.4% to 13.1%, respectively. The relation between these indicators was positive in high-income countries, negative in Central and Eastern Europe, and null in the other region. Age-adjusted CKD prevalence explained 40% of the variance in KRT incidence (P < 0.001) in high-income countries. The explained variance of age-adjusted mortality was close to 0 in high-income countries and positive at 19% (P = 0.10) in Central and Eastern Europe and at 11% (P = 0.17) in the other region. Results were consistent by gender.

Conclusion

This study raises awareness on the significant part of the gaps in KRT incidence across countries not explained by the number of individuals with CKD, even in high-income countries where access to KRT is not limited.

Prevalence of chronic kidney disease in an admixed population of patients with type 1 diabetes. A multicenter study in Brazil

AIMS

To evaluate diagnosis, prevalence and associated factors of CKD in Brazilian patients with type 1 diabetes.

METHODS

This cross-sectional, multicenter study was conducted in 14 public clinics in 10 Brazilian cities. From 1760 patients, 1736 were included (98.6%): 977 females (56.3%), 932 (54%) Caucasians, aged 29.9 ± 11.9 years, age at diagnosis 14.7 ± 8.9 years, diabetes duration 15.5 ± 9.3 years and 12.2 ± 3.8 years of school attendance. CKD was determined by using estimated glomerular filtration rate and by the presence of albuminuria in two out of three morning urine samples.

RESULTS

The prevalence of CKD was 33.7%. Overall, 28.1% of the patients could not be classified due to insufficient number of urine samples for albuminuria determination. Multivariable analysis showed that female gender, diabetes duration, high levels of HbA1c and uric acid, use of renin-angiotensin system inhibitors, retinopathy, high systolic blood pressure, and economic status (medium, low and very low) were associated with CKD.

CONCLUSIONS

Although a high prevalence of CKD, associated comorbidities and retinopathy was observed in our study, a large number of patients are still undiagnosed, making CKD a challenge in routine clinical practice in admixed populations with T1D in a developing country like Brazil.

Serum lipoprotein (a) associates with a higher risk of reduced renal function: a prospective investigation

Lipoprotein (a) [Lp(a)] is a well-known risk factor for cardiovascular disease, but analysis on Lp(a) and renal dysfunction is scarce. We aimed to investigate prospectively the association of serum Lp(a) with the risk of reduced renal function, and further investigated whether diabetic or hypertensive status modified such association. Six thousand two hundred and fifty-seven Chinese adults aged ≤40 years and free of reduced renal function at baseline were included in the study. Reduced renal function was defined as estimated glomerular filtration rate <60 ml/min/1.73 m2 During a mean follow-up of 4.4 years, 158 participants developed reduced renal function. Each one-unit increase in log10-Lp(a) (milligrams per deciliter) was associated with a 1.99-fold (95% CI 1.15-3.43) increased risk of incident reduced renal function; the multivariable-adjusted odds ratio (OR) for the highest tertile of Lp(a) was 1.61 (95% CI 1.03-2.52) compared with the lowest tertile (P for trend = 0.03). The stratified analysis showed the association of serum Lp(a) and incident reduced renal function was more prominent in participants with prevalent diabetes [OR 4.04, 95% CI (1.42-11.54)] or hypertension [OR 2.18, 95% CI (1.22-3.89)]. A stronger association was observed in the group with diabetes and high Lp(a) (>25 mg/dl), indicating a combined effect of diabetes and high Lp(a) on the reduced renal function risk. An elevated Lp(a) level was independently associated with risk of incident reduced renal function, especially in diabetic or hypertensive patients.

Intrauterine Growth Restriction and Risk of Diverse Forms of Kidney Disease during the First 50 Years of Life

BACKGROUND AND OBJECTIVES

Previous studies have shown that individuals with low birth weight (LBW) or small for gestational age (SGA) have higher risk of kidney failure. This study investigates birth-related exposures and risk of CKD and other kidney diagnoses.

DESIGN, SETTING, PARTICIPANT, & MEASUREMENTS

The Medical Birth Registry of Norway has registered extensive medical data on all births in Norway since 1967. The Norwegian Patient Registry has registered diagnostic codes for all admissions and outpatient visits to Norwegian hospitals since 2008. Data from these registries were linked, and risk of CKD and other groups of kidney disease were analyzed using logistic regression statistics. LBW (below the tenth percentile), SGA (birth weight below the tenth percentile for gestational age), and preterm birth (<37 weeks) were analyzed as exposures.

RESULTS

A total of 2,663,010 individuals were included. After a mean follow-up of 26 years (maximum 50 years), 4495 had been diagnosed with CKD and 12,818 had been diagnosed with other groups of kidney disease. LBW was associated with an odds ratio (OR) for CKD of 1.72 (95% confidence interval [95% CI], 1.60 to 1.90), SGA with an OR of 1.79 (95% CI, 1.65 to 1.94), and preterm birth with an OR of 1.48 (95% CI, 1.33 to 1.66). Analyses using diagnosis of CKD at stages 3-5 as end point showed similar results. Results were similar for men and women. We analyzed adjusted ORs for other groups of kidney disease and found that LBW was associated with an adjusted OR of 1.44 (95% CI, 1.33 to 1.56) for acute kidney disease, 1.24 (95% CI, 1.14 to 1.36) for GN, 1.35 (95% CI, 1.17 to 1.56) for cystic kidney disease, and 1.15 (95% CI, 1.06 to 1.25) for kidney disease resulting from kidney or urinary tract malformations.

CONCLUSIONS

LBW, SGA, and preterm birth are associated with higher risk of CKD in the first 50 years of life. Risk of other groups of kidney disease was less pronounced.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_08_17_CJN04080320.mp3.

Nutritional support for patients with chronic kidney disease at pre-dialysis stages

Chronic kidney disease (CKD) is characterized by poor outcomes, an increasing frequency of new cases, the need for expensive method of renal replacement therapy at the terminal stage. The main task facing the doctor is slowing the progression of CKD and delay the start of dialysis by applying the nephroprotective strategy, of which diet therapy is an essential part. The key components of the diet for CKD patients are reducing sodium intake to 2.3 g per day in order to improve control of blood pressure (BP), dietary protein restriction adequate to renal function from 0.8 to 0.3 g/kg of body weight per day combined with the prescribing of ketoanalogues of essential amino acids, hyperglycemia control. With the progression of CKD, the main objectives of the diet therapy are the prevention/correction of complications: protein-energy waisting, metabolic acidosis, ensuring sufficient calories, corresponding to the bodys energy expenditures (3035 kcal/kg of body weight per day), limiting phosphate intake to 0.81 g a day, restriction of food potassium. Low-protein diet in combination with ketoanalogues of amino acids, regular monitoring and correction of the nutritional status of patients at the pre-dialysis stages of CKD is an effective and safe method of nephroprotection, which allows delaying the start of dialysis.

TicagRelor Or Clopidogrel in severe or terminal chronic kidney patients Undergoing PERcutaneous coronary intervention for acute coronary syndrome: The TROUPER trial

Chronic kidney disease (CKD) is associated with an increased risk of acute coronary syndrome (ACS) and cardiovascular death. CKD patients suffering from ACS are exposed to an increased risk of thrombotic recurrences and a higher bleeding rate than patients with normal renal function. However, CKD patients are excluded or underrepresented in clinical trials. Therefore, determining the optimal antiplatelet strategy in this population is of utmost importance. We designed the TicagRelor Or Clopidogrel in severe or terminal chronic kidney patients Undergoing PERcutaneous coronary intervention for acute coronary syndrome (TROUPER) trial: a prospective, controlled, multicenter, randomized trial to investigate the optimal P2Y12 antagonist in CKD patients with ACS. Patients with stage ≥3b CKD are eligible if the diagnosis of ACS is made and invasive strategy scheduled. Patients are randomized 1:1 between a control group with a 600-mg loading dose of clopidogrel followed by a 75-mg/d maintenance dose for 1 year and an experimental group with a 180-mg loading dose of ticagrelor followed by a 90-mg twice daily maintenance dose for the same duration. The primary end point is defined by the rate of major adverse cardiovascular events, including death, myocardial infarction, urgent revascularization, and stroke at 1 year. Safety will be evaluated by the bleeding rate (Bleeding Academic Research Consortium). To demonstrate the superiority of ticagrelor on major adverse cardiovascular events, we calculated that 508 patients are required. The aim of the TROUPER trial is to compare the efficacy of ticagrelor and clopidogrel in stage >3b CKD patients presenting with ACS and scheduled for an invasive strategy. RCT# NCT03357874.

Metabolomics window into the role of acute kidney injury after coronary artery bypass grafting in diabetic nephropathy progression

Introduction

Metabolomics has emerged as a valuable tool to discover novel biomarkers and study the pathophysiology of diabetic nephropathy (DN). However, the effect of postoperative acute kidney injury (AKI) on diabetes mellitus (DM) to chronic DN progression has not been evaluated from the perspective of metabolomics.

Methods

A group of type 2 diabetes mellitus (T2DM) inpatients, who underwent off-pump coronary artery bypass grafting (CABG), were enrolled in our study. According to whether postoperative AKI occurred, patients were grouped in either the AKI group (AKI, n = 44) or the non-AKI group (NAKI, n = 44). Urine samples were collected from these patients before and 24 h after operation. Six patients from the AKI group and six patients from the NAKI group were chosen as the pilot cohort for untargeted metabolomics analysis, with the goal of identifying postoperative AKI-related metabolites. To understand the possible role of these metabolites in the chronic development of renal injury among T2DM patients, trans-4-hydroxy-L-proline and azelaic acid were quantified by targeted metabolomics analysis among 38 NAKI patients, 38 AKI patients, 46 early DN patients (DN-micro group), and 34 overt DN patients (DN-macro group).

Results

Untargeted metabolomics screened 61 statistically distinguishable metabolites in postoperative urine samples, compared with preoperative urine samples. Via Venn diagram analysis, nine of 61 were postoperative AKI-related metabolites, including trans-4-hydroxy-L-proline, uridine triphosphate, p-aminobenzoate, caffeic acid, adrenochrome, δ-valerolactam, L-norleucine, 5′-deoxy-5′-(methylthio) adenosine, and azelaic acid. By targeted metabolomics analysis, the level of trans-4-hydroxy-L-proline increased gradually from the NAKI group to the AKI, DN-micro, and DN-macro groups. For azelaic acid, the highest level was found in the NAKI and DN-micro groups, followed by the DN-macro group. The AKI group exhibited the lowest level of azelaic acid.

Conclusions

The detection of urinary trans-4-hydroxy-L-proline after AKI could be treated as an early warning of chronic DN progression and might be linked to renal fibrosis. Urinary azelaic acid can be used to monitor renal function noninvasively in DM and DN patients. Our results identified markers of AKI on DM and the chronic progression of DN. In addition, the progression of DN was associated with AKI-like episodes occurring in DM.

Longitudinal trends in the prevalence of hyperuricaemia and chronic kidney disease in hypertensive and normotensive adults

The purpose: To evaluate longitudinal trends in the prevalence of hyperuricaemia and chronic kidney disease (CKD) in Czech adults with and without arterial hypertension (HT).Materials and methods: Two independent cross-sectional surveys were performed in 2006-2009 and 2015-2018, each screening involving 1% population random sample of the general population of nine districts of the Czech Republic aged 25-64 years, stratified by age and gender. Hyperuricaemia was defined as serum uric acid ≥ 420 μmol/l in men, and ≥ 360 μmol/l in women. CKD was defined as estimated glomerular filtration rate < 60 ml/min/1.73 m² and/or albumin/creatinine ratio ≥ 3 mg/mmol.Results: Final analyses included 3504 individuals examined in 2006-2009, and 2309 in 2015-2018. The overall prevalence of hyperuricaemia increased from 16.4% to 25.2% in men (p < 0.001), and from 7.6% to 10.9% in women (p < 0.001), whereas the overall prevalence of CKD declined from 6.8% to 3.6% in men (p = 0.001), and from 7.6% to 4.8% in women (p < 0.001). There was no interaction between HT and hyperuricaemia in either gender; the increase in hyperuricaemia prevalence was observed both in hypertensive and normotensive adults and was accompanied by the increased prevalence of abdominal obesity. Contrarily, there was an interaction between HT and CKD in both men (p < 0.001) and women (p = 0.011); the CKD prevalence declined only in hypertensive individuals, specifically in those using antihypertensive medication and was accompanied by the increased use of renin-angiotensin-aldosterone system (RAS) inhibitors and calcium channel blockers (CCBs).Conclusions: Over the period of 10 years, the overall prevalence of hyperuricaemia increased, while the prevalence of CKD decreased. An increase in the prevalence of hyperuricaemia was observed both in hypertensive and normotensive individuals and was accompanied by an increase in the prevalence of abdominal obesity. A decline in the prevalence of CKD was only observed in hypertensive individuals and was accompanied by the increased use of RAS inhibitors and CCBs.

Isoliquiritigenin Attenuates UUO-Induced Renal Inflammation and Fibrosis by Inhibiting Mincle/Syk/NF-Kappa B Signaling Pathway

Purpose

Chronic kidney disease (CKD) is a global nephrotic syndrome characterized by chronic inflammation, oxidative stress and fibrosis in the kidney. Isoliquiritigenin (ISL), a flavonoid from licorice, has historically been reported to inhibit innate immune responses to inflammation and fibrosis in vivo. However, the effect of ISL on CKD progression is largely unknown.

Materials and Methods

In this study, we employed the inflammatory and fibrotic models of LPS/TGF-β-induced bone marrow-derived macrophages (BMDM) in vitro and unilateral ureteral obstruction (UUO) model in vivo to explore the potential effects and mechanism of ISL on renal inflammation and fibrosis.

Results

Our results manifest that ISL improved UUO-induced renal dysfunction and reduced tubular damage with a significantly downregulated mRNA expression and secretion of IL-1β, IL-6, TNF-α and MCP-1 in vitro and in vivo. It is worth noting that ISL can strongly inhibit the mRNA and protein expression of Mincle (macrophage-induced c-type lectin) in BMDM and UUO. ISL inhibited the phosphorylation of Syk and NF-kappa B and simultaneously reduced the expression of α-SMA and Col III in vivo and in vitro. More interestingly, when dealing with TDB, a ligand of Mincle, it revealed significant reversal of protein expression levels as that observed with ISL. The expressions of IL-1β, IL-6, TNF-α, iNOS, p-Syk, p-NF-kappa B, α-SMA and FN in BMDM inflammatory model were significantly upregulated with TDB treatment. This confirms that ISL inhibits inflammation and fibrosis of macrophage by suppressing Mincle/Syk/NF-kappa B signaling pathway.

Conclusion

To conclude, ISL protects UUO-induced CKD by inhibiting Mincle-induced inflammation and suppressing renal fibrosis, which might be a specific renal protective mechanism of ISL, making it a novel drug to ameliorate CKD.