Patient characteristics and outcomes by GN subtype in ESRD

Incidence and outcomes of kidney replacement therapy for end-stage kidney disease due to primary glomerular disease in Europe: findings from the ERA Registry

BACKGROUND

Primary glomerular disease (PGD) is a major cause of end-stage kidney disease (ESKD) leading to kidney replacement therapy (KRT). We aimed to describe incidence (trends) in individuals starting KRT for ESKD due to PGD and to examine their survival and causes of death.

METHODS

We used data from the European Renal Association (ERA) Registry on 69 854 patients who started KRT for ESKD due to PGD between 2000 and 2019. ERA primary renal disease codes were used to define six PGD subgroups. We examined age and sex standardized incidence, trend of the incidence and survival.

RESULTS

The standardized incidence of KRT for ESKD due to PGD was 16.6 per million population (pmp), ranging from 8.6 pmp in Serbia to 20.0 pmp in France. Immunoglobulin A nephropathy (IgAN) and focal segmental glomerulosclerosis (FSGS) had the highest incidences, of 4.6 pmp and 2.6 pmp, respectively. Histologically non-examined PGDs represented over 50% of cases in Serbia, Bosnia and Herzegovina, and Romania and were also common in Greece, Estonia, Belgium and Sweden. The incidence declined from 18.6 pmp in 2000 to 14.5 pmp in 2013, after which it stabilized. All PGD subgroups had 5-year survival probabilities above 50%, with crescentic glomerulonephritis having the highest risk of death [adjusted hazard ratio 1.8 (95% confidence interval 1.6-1.9)] compared with IgAN. Cardiovascular disease was the most common cause of death (33.9%).

CONCLUSION

The incidence of KRT for ESKD due to PGD showed large differences between countries and was highest and increasing for IgAN and FSGS. Lack of kidney biopsy facilities in some countries may have affected accurate assignment of the cause of ESKD. The recognition of the incidence and outcomes of KRT among different PGD subgroups may contribute to a more individualized patient care approach.

Clinical Characteristics and Histopathology in Adults With Focal Segmental Glomerulosclerosis

Rationale & Objective

Few data are available regarding histological features at the time of focal segmental glomerulosclerosis (FSGS) diagnosis among diverse real-world populations. This study describes clinical and histological characteristics and correlates of histological disease severity in adults with FSGS who underwent a clinical kidney biopsy.

Study Design

Real-world cohort study with data derived from health records.

Setting & Participants

Adults with FSGS by kidney biopsies from Arkana Laboratories from January 1, 2016 to May 31, 2020.

Exposure

Race, chronic kidney disease stage, nephrotic proteinuria, age, sex, and hypertension.

Outcomes

Severe histological disease, defined as global glomerulosclerosis in >50% of glomeruli and >25% interstitial fibrosis and tubular atrophy (IFTA).

Analytical Approach

Demographic, clinical, and histological characteristics were compared between race groups. Correlates of severe disease were analyzed using multiple logistic regression.

Results

Among 2,011 patients with FSGS, 40.6% were White, and 23.6% Black. White patients were older (52.8 vs 45.5 years, P < 0.001) with a higher estimated glomerular filtration rate (eGFR) than Black patients (53.5 vs 43.1 mL/min/1.73 m2, P < 0.001). A higher proportion of Black patients had global glomerulosclerosis ≥50% (32.1% vs 14.6%, P < 0.001) or IFTA >50% (34.6% vs 14.7%, P < 0.001). Severe histological disease was more likely in Black patients (OR, 2.46; 95% CI, 1.59-3.79; P < 0.001). A higher proportion of patients with nephrotic than nonnephrotic proteinuria exhibited diffuse foot process effacement.

Limitations

Unequal representation across United States regions, missing demographic and clinical data, and lack of data on primary versus secondary FSGS, treatments, or outcomes.

Conclusions

Black patients were more frequently diagnosed at younger age with lower eGFR and more severe histological disease compared with White patients. Timelier identification of FSGS could increase the opportunity for therapeutic intervention, especially for high-risk patients, to mitigate disease progression and complications.

Plain-Language Summary

Focal segmental glomerulosclerosis (FSGS) accounts for around one-quarter of diagnoses derived from clinical kidney biopsies in the United States. Limited data are available regarding the classes and distribution of histological features at FSGS diagnosis among diverse real-world populations. Analyzing data from US patients who underwent kidney biopsy and were diagnosed with FSGS, we showed that up to half of patients had features of severe histological disease. Of this overall population, Black patients were more frequently diagnosed at a younger age but with more severe histological disease than White patients. The work highlights the need for timelier diagnosis of FSGS to enable intervention at an earlier disease stage.

Years of life lost and long-term outcomes due to glomerular disease in a Southeast Asian Cohort

Death and end-stage kidney disease (ESKD) are major outcomes of glomerular disease. (GD) The years of potential life lost (YLL) may provide additional insight into the disease burden beyond death rates. There is limited data on premature mortality in GD. In this retrospective observational cohort study, we evaluated the mortality, ESKD rates, and YLL in Thais with biopsy-proven GD. The mortality and combined outcome rates were determined by log-rank test and ESKD by using a competing risk model. YLL and premature life lost before age 60 were calculated for different GD based on the life expectancy of the Thai population. Patients with GD (n = 949) were followed for 5237 patient years. The death rate and ESKD rates (95%CI) were 4.2 (3.7-4.9) and 3.3 (2.9-3.9) per 100 patient-years, respectively. Paraprotein-related kidney disease had the highest death rate, and diabetic nephropathy had the highest ESKD rate. Despite not having the highest death rate, lupus nephritis (LN) had the highest YLL (41% of all GD) and premature loss of life before age 60. In conclusion, YLL provided a different disease burden assessment compared to mortality rates and identified LN as the major cause of premature death due to GD in a Southeast Asian cohort.

The outcomes of patients with kidney failure due to focal segmental glomerulosclerosis (FSGS) in Australia and New Zealand: A cohort study using the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA)

BACKGROUND

The outcomes of patients with focal segmental glomerulosclerosis (FSGS) on kidney replacement therapy (KRT) have not been well described. This study evaluated the outcomes of patients with kidney failure due to FSGS on KRT including dialysis and kidney transplantation.

METHOD AND MATERIALS

All adult patients with kidney failure who commenced KRT in Australia and New Zealand from 15th of May 1963 to 31st of December 2018 were retrospectively extracted from the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. Outcomes of patients with FSGS were compared to those with other causes of kidney failure (non-FSGS).

RESULTS

85,052 patients commenced KRT during the study period, of whom 2991 (3.5%) were patients with FSGS. Compared to patients with non-FSGS, patients with FSGS experienced similar mortality on dialysis (adjusted hazard ratio [aHR] 0.98, 95% CI 0.90-1.06, p = 0.55) and following kidney transplantation (aHR 0.92, 95% CI 0.73-1.15, p = 0.47). The risk of first kidney allograft loss was higher in patients with FSGS (aHR 1.20, 95% CI 1.04-1.37, p = 0.01). However, when death was analysed as a competing risk, the survival in both groups was similar (sub-hazard ratio [SHR] 1.09, 95% CI 0.94-1.28, p = 0.26). Patients with FSGS had a longer waiting time for kidney transplantation (aHR 0.92, 95% CI 0.86-0.98, p = 0.02) and experienced an increased risk of disease recurrence in the allograft (aHR 1.73, 95% CI 1.35-2.21, p<0.001). Compared to patients with other forms of glomerular disease, patients with FSGS experienced similar dialysis and transplant patient survival and death-censored rate of kidney transplantation and allograft loss but higher rates of primary kidney disease recurrence.

CONCLUSION

FSGS was associated with similar dialysis and transplant patient survival and death-censored first allograft loss compared to non-FSGS and other forms of glomerular disease.

General prognostic models may neglect vulnerable subgroups in ANCA-associated vasculitis

BACKGROUND

ANCA-associated vasculitis is an organ and life-threatening disease with the highest incidence in elderly patients. However, few studies have focussed on characteristics and treatment outcomes in a direct comparison of elderly and younger patients.

METHODS

In a retrospective, single-centre, renal biopsy-cohort, patients were dichotomized by age ≥ 65 years to analyse baseline clinical, histological, laboratory and immunological characteristics and outcome differences in elderly and younger patients as regard to mortality, renal recovery from dialysis and eGFR after two years.

RESULTS

In the biopsy registry, n = 774 patients were identified, of whom 268 were ≥ 65 years old. Among them, ANCA-associated vasculitis was the most prevalent kidney disease (n = 54 ≈ 20%). After a follow-up of 2 years, overall mortality was 13.4%, with 19% and 4% in patients ≥ and < 65 years of age, respectively. While 41% of elderly and 25% of younger patients were dialysis-dependent at the time of biopsy, renal recovery was achieved in 41% and 57% of patients, respectively. The accuracy of prediction differed significantly between the whole cohort and elderly patients as regard to mortality (sensitivity 46% vs. 90%, respectively) and between younger and elderly patients as regard to eGFR (r2 = 0.7 vs. 0.46, respectively). Age-group-wise analysis revealed patients above 80 years of age to have particularly dismal renal outcome and survival.

CONCLUSION

In our cohort, ANCA-associated vasculitis is the single most frequent histopathological diagnosis among the elderly patients in our cohort. Elderly and younger patients have comparable chances of recovering from dialysis-dependent renal failure, with comparable residual independent kidney function after two years. This study suggests (1) relevant predictors differ between age groups and hence (2) models involving all patients with ANCA-associated vasculitis neglect important features of vulnerable subgroups, i.e., patients above 80 years old.

The Long-Term Survival Outcome in Older Patients with Different Pathological Types of Chronic Kidney Disease

INTRODUCTION

Chronic kidney diseases (CKDs) are prevalent in older people, and renal pathological manifestations are important for diagnosis, treatment, and prognosis. However, the long-term survival outcome and risk factors for older CKD patients with different pathological types are not fully understood and need to be further investigated.

METHODS

Medical data were recorded and all-cause mortality was followed up in patients who underwent renal biopsy diagnosed in Guangdong Provincial People's Hospital from 2005 to 2015. Kaplan-Meier analysis was used to identify the incidence of survival outcomes. Multivariate Cox regression models and nomograms were applied to analyze pathological types and other factors for overall survival outcomes.

RESULTS

368 cases were included and the median follow-up was 85 (46.5, 111) months. Overall mortality was 35.6%. The highest mortality was in the mesangioproliferative glomerulonephritis (MPGN) group (88.9%), followed by amyloidosis (AMY) group (84.6%), and the lowest mortality was in the minimal change disease (MCD) group (21.9%). Moreover, multivariate Cox regression model showed that survival times of MPGN {hazard ratio (HR) = 8.215 (95% confidence interval [CI]: 2.735-24.674), p < 0.001} and AMY (HR = 6.130 [95% CI: 2.219-16.94], p < 0.001) were significantly shorter than MCD. In addition, age, lower baseline estimated glomerular filtration rate (eGFR), history of chronic obstructive pulmonary disease (COPD) and cerebrovascular accidents (CVA)/transient ischemic attack (TIA), MPGN, and AMY were independent risk factors for the mortality of older patients with CKD.

CONCLUSION

The long-term survival outcome of older CKD patients showed differences among different pathological types, and MPGN, AMY, age, baseline eGFR, CVA/TIA, and COPD were independent predictors for mortality.

Network Pharmacology and Experimental Validation to Explore That Celastrol Targeting PTEN is the Potential Mechanism of Tripterygium wilfordii (Lév.) Hutch Against IgA Nephropathy

Purpose

Accumulating clinical evidence showed that Tripterygium hypoglaucum (Lév.) Hutch (THH) is effective against IgA nephropathy (IgAN), but the mechanism is still unclear. This study is to evaluate the renal protective effect and molecular mechanism of THH against IgAN via network pharmacology, molecular docking strategy and experimental validation.

Methods

Several databases were used for obtaining the active ingredients of THH, the corresponding targets, as well as the IgAN-related genes. The critical active ingredients, functional pathways, and potential for the combination of the hub genes and their corresponding active components were determined through bioinformatics analysis and molecular docking. The IgAN mouse model was treated with celastrol (1 mg/kg/d) for 21 days, and the aggregated IgA1-induced human mesangial cell (HMC) was treated with various concentrations of celastrol (25, 50 or 75 nM) for 48 h. The immunohistochemistry and Western blot techniques were applied to evaluate the protein expression of the predicted target. The cell counting kit 8 (CCK8) was used to detect HMC proliferation.

Results

A total of 17 active ingredients from THH were screened, covering 165 IgAN-related targets. The PPI network identified ten hub targets, including PTEN. The binding affinity between the celastrol and PTEN was the highest (-8.69 kJ/mol). The immunohistochemistry showed that celastrol promoted the expression of PTEN in the glomerulus of IgAN mice. Furthermore, the Western blot techniques showed that celastrol significantly elevated the expression of PTEN and inhibited PCNA and Cyclin D1 in vitro and in vivo. The CCK8 assay determined that celastrol decreased HMC proliferation in a concentration-dependent manner.

Conclusion

This study suggests that activating PTEN by celastrol may play a pivotal role in THH alleviating IgAN renal injury.

Infection profile and risk factors for mortality in patients with end-stage renal disease attributable to systemic lupus erythematosus: a two-center integrated study

Objective

Renal impairment is a significant complication of systemic lupus erythematosus (SLE). Additionally, infection in patients with end-stage renal disease (ESRD) attributable to SLE is common, and it increases the risk of mortality. This study explored the infection profile and risk factors for mortality in patients with ESRD attributable to SLE.

Methods

In this retrospective, observational study of 125 hospitalized patients, demographic, clinical, laboratory, treatment, and prognosis data were retrieved and analyzed.

Results

The 125 cases included 98 pulmonary infections (78.4%), 14 urinary infections (11.2%), and 13 intestinal infections (10.4%). Twenty-six patients died within 1 month after enrollment. Univariate Cox regression and Kaplan–Meier analyses revealed several possible indicators potentially influencing patient survival. Furthermore, multivariate Cox regression analysis identified a higher SLE Disease Activity Index-2000 score, recent higher-dose glucocorticoid use, hypertension, and catheter indwelling as risk factors for higher mortality.

Conclusions

Infections were common in patients with advanced SLE and ESRD, and several risk factors might increase the risk of mortality. Once infection is identified, empiric antibiotics should be initiated immediately, and subsequent antibiotics should be applied per the results of drug sensitivity testing to clear the infection.

Post-Transplant Cardiovascular Disease

Cardiovascular disease remains a leading cause of death and morbidity in kidney transplant recipients and a common reason for post-transplant hospitalization. Several traditional and nontraditional cardiovascular risk factors exist, and many of them present pretransplant and worsened, in part, due to the addition of immunosuppression post-transplant. We discuss optimal strategies for identification and treatment of these risk factors, including the emerging role of sodium-glucose cotransporter 2 inhibitors in post-transplant diabetes and cardiovascular disease. We present common types of cardiovascular disease observed after kidney transplant, including coronary artery disease, heart failure, pulmonary hypertension, arrhythmia, and valvular disease. We also discuss screening, treatment, and prevention of post-transplant cardiac disease. We highlight areas of future research, including the need for goals and best medications for risk factors, the role of biomarkers, and the role of screening and intervention.

A Retrospective Study of Clinical and Economic Burden of Focal Segmental Glomerulosclerosis (FSGS) in the United States

Introduction

Information on the economic burden of focal segmental glomerulosclerosis (FSGS) is sparse. This study characterized health care resource utilization (HCRU) and costs in patients with FSGS, and evaluated the impact of nephrotic range proteinuria on these outcomes.

Methods

This retrospective, observational cohort study used administrative claims data from the Optum Clinformatics Data Mart Database from October 2015 to December 2019. Patients with FSGS (n = 844; first claim = index event) between April 2016 and December 2018 were matched on index date, age, sex, and race to non-FSGS controls (n = 1688). FSGS nephrotic range (urine protein/creatinine ratio >3000 mg/g or albumin/creatinine ratio >2000 mg/g) and non-nephrotic subpopulations were identified. Baseline comorbidities, 12-month post-index all-cause HCRU and costs (per patient per year [PPPY]), and immunosuppressant prescriptions were compared between matched cohorts and between FSGS subpopulations.

Results

Comorbidity burden was higher in FSGS. Of 308 patients with available urine protein/creatinine ratio/albumin/creatinine ratio results, 36.4% were in nephrotic range. All-cause HCRU was higher in FSGS across resource categories (all P < 0.0001); 50.6% of FSGS and 23.3% of controls were prescribed glucocorticoids (P < 0.0001). Mean total medical costs were higher in FSGS ($59,753 vs. $8431 PPPY; P < 0.0001), driven by outpatient costs. Nephrotic range proteinuria was associated with higher all-cause inpatient, outpatient, and prescription costs versus nonnephrotic patients (all P < 0.0001), resulting in higher total costs ($70,481 vs. $36,099 PPPY; P < 0.0001).

Conclusions

FSGS is associated with significant clinical and economic burdens; the presence of nephrotic range proteinuria increased the economic burden. New treatment modalities are needed to reduce proteinuria, help improve patient outcomes, and reduce HCRU and associated costs.

Peritoneal dialysis in incident patients with primary glomerulonephritis. Results of a 20-year multicenter registry study

BACKGROUND AND OBJECTIVES

Glomerulonephritis (GN) is one of the main causes of chronic terminal kidney disease; however, few studies assess its prognosis in dialysis. We analyze the survival and characteristics of patients on peritoneal dialysis (PD) with primary GN (PGN), and compare their results with other kidney patients.

METHODS

This prospective observational study took place from 1995 to 2014. We included all incident patients who were initiated on the technique in the Levante registry. Data were transferred to an anonymized database in Access. Statistical analysis was performed using SPSS software (version 19.0).

RESULTS

The study included 2243 patients, with GN representing the main cause of primary kidney disease (21,5%). IgA nephropathy was the most frequent histologically confirmed form of PGN. Compared with the rest of the sample, patients with PGN were more often men (65% vs 58%, p = .004), and they were on average younger (48 years vs 55 years, p < .001). They also had fewer comorbidities and a higher rate of inclusion on the waitlist for a kidney transplant (87 vs 63%, p < .001). Patients with PGN also had more transplants (48,9%, p < .001), and this was the most frequent reason for stopping PD; beyond that, their peritonitis mean rate was lower (0,34 vs 0,45 episodes/patient-year, p < .001). Technique survival was 90,6% at one year, 71,7% at 3 years, and 59,0% at 5 years (median 76,8 months); there were no differences between groups. Survival was 94,9% at one year, 80,1% at 3 years, and 63,7% at 5 years (median 90,7 months). Patients with PGN showed better mean survival than patients with other kidney pathologies (153,5 months [95% IC: 137,0-169,9] vs 110,3 months [95% CI: 100,8-119,7], p < .001). In the multivariable analysis, the main negative risk factor influencing technique survival was a higher peritoneal transport (p = .018). Factors with a negative influence on mortality were being older (p < .001) and having any comorbidity, mainly diabetes and liver disease (p < .001). By contrast, protective survival factors were inclusion on the transplant waitlist and a higher baseline residual renal function (p = .001).

CONCLUSIONS

PD has several advantages as a first dialytic treatment, and our results suggest that it is an excellent technique to manage patients with PGN while they await a kidney transplant.

Recurrent Glomerulonephritis after Renal Transplantation: The Clinical Problem

Glomerulonephritis (GN) continues to be one of the main causes of end-stage kidney disease (ESKD) with an incidence rating from 10.5% to 38.2%. Therefore, recurrent GN, previously considered to be a minor contributor to graft loss, is the third most common cause of graft failure 10 years after renal transplantation. However, the incidence, pathogenesis, and natural course of recurrences are still not completely understood. This review focuses on the most frequent diseases that recur after renal transplantation, analyzing rate of recurrence, epidemiology and risk factors, pathogenesis and bimolecular mechanisms, clinical presentation, diagnosis, and therapy, taking into consideration the limited data available in the literature. First of all, the risk for recurrence depends on the type of glomerulonephritis. For example, recipient patients with anti-glomerular basement membrane (GBM) disease present recurrence rarely, but often exhibit rapid graft loss. On the other hand, recipient patients with C3 glomerulonephritis present recurrence in more than 50% of cases, although the disease is generally slowly progressive. It should not be forgotten that every condition that can lead to chronic graft dysfunction should be considered in the differential diagnosis of recurrence. Therefore, a complete workup of renal biopsy, including light, immunofluorescence and electron microscopy study, is essential to provide the diagnosis, excluding alternative diagnosis that may require different treatment. We will examine in detail the biomolecular mechanisms of both native and transplanted kidney diseases, monitoring the risk of recurrence and optimizing the available treatment options.

Peritoneal dialysis in incident patients with primary glomerulonephritis. Results of a 20-year multicenter registry study

BACKGROUND AND OBJECTIVES

Glomerulonephritis (GN) is one of the main causes of chronic terminal kidney disease; however, few studies assess its prognosis in dialysis. We analyze the survival and characteristics of patients on peritoneal dialysis (PD) with primary GN (PGN), and compare their results with other kidney patients.

METHODS

This prospective observational study took place from 1995 to 2014. We included all incident patients who were initiated on the technique in the Levante registry. Data were transferred to an anonymized database in Access. Statistical analysis was performed using SPSS software (version 19.0).

RESULTS

The study included 2,243 patients, with GN representing the main cause of primary kidney disease (21,5%). IgA nephropathy was the most frequent histologically confirmed form of PGN. Compared with the rest of the sample, patients with PGN were more often men (65% vs 58%, P=.004), and they were on average younger (48 years vs 55 years, P<.001). They also had fewer comorbidities and a higher rate of inclusion on the waitlist for a kidney transplant (87 vs 63%, P<.001). Patients with PGN also had more transplants (48,9%, P<.001), and this was the most frequent reason for stopping PD; beyond that, their peritonitis mean rate was lower (0,34 vs 0,45 episodes/patient-year, P<.001). Technique survival was 90,6% at one year, 71,7% at 3 years, and 59,0% at 5 years (median 76,8 months); there were no differences between groups. Survival was 94,9% at one year, 80,1% at 3 years, and 63,7% at 5 years (median 90,7 months). Patients with PGN showed better mean survival than patients with other kidney pathologies (153,5 months [95% IC: 137,0 to 169,9] vs 110,3 months [95% CI: 100,8 to 119,7], P<.001). In the multivariable analysis, the main negative risk factor influencing technique survival was a higher peritoneal transport (P=.018). Factors with a negative influence on mortality were being older (P <.001) and having any comorbidity, mainly diabetes and liver disease (P <.001). By contrast, protective survival factors were inclusion on the transplant waitlist and a higher baseline residual renal function (P=.001).

CONCLUSIONS

PD has several advantages as a first dialytic treatment, and our results suggest that it is an excellent technique to manage patients with PGN while they await a kidney transplant.

Systematic review and meta-analysis of clinical outcomes comparison between different initial dialysis modalities in end-stage renal disease patients due to lupus nephritis prior to renal transplantation

BACKGROUND

Regarding lupus disease activity, morbidity and survival, limited literature concluded conflicting results when comparing hemodialysis versus peritoneal dialysis as initial renal replacement therapies (RRT) prior to transplantation, in lupus nephritis end-stage renal disease (LN-ESRD) patients. This study was aimed to compare the risks of lupus flares, all-cause infections, all-cause cardiovascular events, and mortality, between hemodialysis versus peritoneal dialysis as initial RRT - modality before renal-transplant in LN-ESRD patients, by systematic review and meta-analysis.

METHODS

PubMed, EMBASE, and SCOPUS were searched for observational-studies comparing LN-ESRD -patients undergoing hemodialysis (Group1) versus peritoneal-dialysis (Group 2) prior to renal-transplantation, by their risks of lupus flare, all-cause infections, all-cause cardiovascular events, and mortality as outcome measures. Relative-Risks of outcomes between the groups measured overall effects at a 95% significance level. RevMan 5.3 computer software was used for analysis.

RESULTS

From search, 16 eligible studies reported 15,636 LN-ESRD -patients prior to renal transplantation with 4616 patients on hemodialysis, 2089 on peritoneal dialysis, 280 directly underwent kidney transplantation, 8319 were eliminated with reasons and 332 participants' details were not reported. Hemodialysis group had higher risk of all-cause cardiovascular events, Relative-Risk = 1.44 (Confidence Interval:1.02, 2.04), p-Value< 0.05. With regards to risks for mortality, flare and all-cause infections, there were trends that were not statistically significant (p-Value> 0.05).

CONCLUSION

Except for all-cause cardiovascular events in which peritoneal dialysis is superior to hemodialysis offering better outcomes, both treatment modalities offer more or less similar clinical outcomes as effective initial choices of RRT in LN-ESRD patients prior to renal transplant.

THE PROTOCOL REGISTRATION

PROSPERO 2019 CRD42019131600.

Spatiotemporal trends and prognosis of end-stage renal disease patients with biopsy-proven immunoglobulin A nephropathy in France from 2010 to 2014

Background

Although end-stage renal disease (ESRD) is frequently used as an outcome marker for primary immunoglobulin A nephropathy (IgAN), the clinical course after reaching ESRD is not well documented. This study examined patients’ characteristics and survival in ESRD-related biopsy-proven IgAN in France.

Methods

French Renal Epidemiology and Information Network Registry data from 2010 to 2014 were used to analyse patients’ survival and outcome in incident ESRD patients >16 years of age with biopsy-proven primary IgAN, in comparison with other primary and secondary glomerulonephritis (GN), adult polycystic kidney disease (ADPKD) or diabetes. Multivariable survival analysis was adjusted for age, sex, time on dialysis and comorbidities.

Results

Among 17 138 incident dialysis patients with ESRD, IgAN (242.8/10 000 dialysis initiation) represents the most common GN related to ESRD during 2010. IgAN patients were the youngest, and had the fewest comorbidities and the highest use of peritoneal dialysis (PD) (17%). In comparison with the haemodialysis group, hazard ratios for death were not different in the preemptive transplantation group [0.46, 95% confidence interval (CI) 0.17–1.28] and in the PD group (0.77, 95% CI 0.44–1.33). Mortality rates in IgAN patients with preemptive transplantation and in those receiving dialysis waiting for transplantation were 2.9% (95% CI 0.0–5.6) and 6.7% (95% CI 0.9–12.3). Mortality rates of ADPKD patients receiving dialysis waiting for transplantation were higher (18%, 95% CI 3.1–30.6).

Conclusion

IgAN has the best prognosis among primary and secondary GN. IgAN patients receiving dialysis waiting transplantation seem to have a more favourable prognosis than ADPKD patients, who usually comprise the reference population. The underlying reasons for the difference in access treatment modalities should be investigated to improve survival with respect to renal disease.

Streptococcus may aggravate inflammatory damage in chronic nephritis via the chemotaxis of Th22 cells

BACKGROUND

Infection can induce and aggravate chronic kidney disease (CKD), and the chemotaxis of Th22 cells may aggravate CKD. However, the mechanism underlying group A Streptococcus (GAS) infections in CKD through the chemotaxis of Th22 cells remains unknown.

METHODS

The experiment was divided into a normal control group, an IgAN model group, a GAS-treated normal group, a GAS-treated IgAN group and an anti-CCL intervention group. An IgA nephropathy model was established, and after the success of the IgA nephropathy model was confirmed, Streptococcus haemolyticus A was inoculated intranasally and compared with treatment with anti-CCL to detect changes in Th22 cells, related chemotaxis factors and kidney pathology before and after intervention.

RESULTS

An immunoglobulin A nephropathy model was successfully established. Streptococcus was successfully inoculated into the nasal cavity of the normal group and the IgA nephropathy infection control group. After intervention, pulmonary inflammatory cell infiltration was more obvious in the IgA nephropathy group than in the normal control group after Streptococcus infection. Th22 cells were detected more frequently in IgA nephropathy; after streptococcal infection, the percentage of Th22 cells in the IgAN group was higher than that in the normal group but decreased significantly when chemotaxis was blocked, the expression of CCL27, CCR10 and IL-22 declined simultaneously, and improvements in pathological changes were observed.

CONCLUSION

Streptococcus may cause the chemotaxis of Th22 cells to kidney tissue, leading to or aggravating nephritis injury.

Long-term outcomes of patients with end-stage kidney disease due to membranous nephropathy: A cohort study using the Australia and New Zealand Dialysis and Transplant Registry

Background

Clinical outcomes of patients with end-stage kidney disease (ESKD) secondary to membranous nephropathy (MN) have not been well described. This study aimed to evaluate patient and/or allograft outcomes of dialysis or kidney transplantation in patients with ESKD secondary to MN.

Material and methods

All adult patients with ESKD commencing renal replacement therapy in Australia and New Zealand from January 1998 to December 2010 were extracted retrospectively from ANZDATA registry on 31^st December 2013. Outcomes of MN were compared to other causes of ESKD. In a secondary analysis, outcomes of MN were compared to all patients with ESKD due to other forms of glomerulonephritis.

Results

Of 32,788 included patients, 417 (1.3%) had MN. Compared to other causes of ESKD, MN experienced lower mortality on dialysis (adjusted hazard ratio [aHR] 0.79, 95% CI 0.68–0.92, p = 0.002) and following kidney transplantation (aHR 0.57, 95% CI 0.33–0.97, p = 0.04), had a higher risk of death-censored kidney allograft failure (aHR 1.55, 95% CI: 1.00–2.41, p = 0.05) but comparable risk of overall kidney allograft failure (aHR 1.35, 95% CI 0.91–2.01, p = 0.13). Similar results were obtained using competing-risk regression analyses. MN patients were significantly more likely to receive a kidney transplant (aHR 1.38, 95% CI 1.16–1.63, p<0.001) and to experience primary kidney disease recurrence in the allograft (aHR 4.92, 95% CI 3.02–8.01, p<0.001). Compared to other forms of glomerulonephritis, MN experienced comparable dialysis and transplant patient survival, but higher rates of kidney transplantation, primary renal disease recurrence and death-censored allograft failure.

Conclusion

MN was associated with superior survival on dialysis and following kidney transplantation compared to patients with other causes of ESKD, and comparable patient survival compared to patients with other forms of glomerulonephritis. However, patients with MN exhibited a higher rate of death-censored allograft loss as a result of primary kidney disease recurrence.

Recurrent and de novo Glomerulonephritis After Kidney Transplantation

The prevalence, pathogenesis, predictors, and natural course of patients with recurrent glomerulonephritis (GN) occurring after kidney transplantation remains incompletely understood, including whether there are differences in the outcomes and advances in the treatment options of specific GN subtypes, including those with de novo GN. Consequently, the treatment options and approaches to recurrent disease are largely extrapolated from the general population, with responses to these treatments in those with recurrent or de novo GN post-transplantation poorly described. Given a greater understanding of the pathogenesis of GN and the development of novel treatment options, it is conceivable that these advances will result in an improved structure in the future management of patients with recurrent or de novo GN. This review focuses on the incidence, genetics, characteristics, clinical course, and risk of allograft failure of patients with recurrent or de novo GN after kidney transplantation, ascertaining potential disparities between “high risk” disease subtypes of IgA nephropathy, idiopathic membranous glomerulonephritis, focal segmental glomerulosclerosis, and membranoproliferative glomerulonephritis. We will examine in detail the management of patients with high risk GN, including the pre-transplant assessment, post-transplant monitoring, and the available treatment options for disease recurrence. Given the relative paucity of data of patients with recurrent and de novo GN after kidney transplantation, a global effort in collecting comprehensive in-depth data of patients with recurrent and de novo GN as well as novel trial design to test the efficacy of specific treatment strategy in large scale multicenter randomized controlled trials are essential to address the knowledge deficiency in this disease.

Type 2 diabetes and the kidney: Insights from cardiovascular outcome trials

Diabetic kidney disease (DKD) still remains a progressive condition that is associated with higher risk of end-stage kidney disease and significant cardiovascular morbidity and mortality. Twelve cardiovascular outcome trials in type 2 diabetes (T2D) have been published to date. Most trials with dipeptidyl-peptidase inhibitors (SAVOR-TIMI 53 with saxagliptin, EXAMINE with alogliptin, TECOS with sitagliptin, and CARMELINA with linagliptin) and with glucagon-like peptide-1 receptor agonists (GLP-1RAs) (ELIXA with lixisenatide, LEADER with liraglutide, SUSTAIN-6 with semaglutide, EXCSEL with exenatide once-weekly, and HARMONY with albiglutide) pointed towards reduced albuminuria, which is a surrogate endpoint possibly heralding renal function preservation. The three trials with sodium-glucose co-transporter-2 inhibitors (SGLT-2is) (empagliflozin, canagliflozin and dapagliflozin) also showed a salutary effect on long-term estimated glomerular filtration rate, suggesting that SGLT-2is are more effective at mitigating loss of kidney function than incretin-based therapies; moreover, SGLT-2is also have the advantage of plausible haemodynamic mechanisms for improved renal outcomes. Despite some residual limitations linked to differences in study populations and patient characteristics, the cardiorenal protective actions of SGLT-2is, and to a lesser extent some GLP-1RAs, make them favourable medications for patients with T2D at increased cardiorenal risk. There is room for optimism that their use may change the paradigm of the ineluctable progression of DKD.

SGLT2 Inhibitors: Nephroprotective Efficacy and Side Effects

The burden of diabetic kidney disease (DKD) has increased worldwide in the last two decades. Besides the growth of diabetic population, the main contributors to this phenomenon are the absence of novel nephroprotective drugs and the limited efficacy of those currently available, that is, the inhibitors of renin-angiotensin system. Nephroprotection in DKD therefore remains a major unmet need. Three recent trials testing effectiveness of sodium-glucose cotransporter 2 inhibitors (SGLT2-i) have produced great expectations on this therapy by consistently evidencing positive effects on hyperglycemia control, and more importantly, on the cardiovascular outcome of type 2 diabetes mellitus. Notably, these trials also disclosed nephroprotective effects when renal outcomes (glomerular filtration rate and albuminuria) were analyzed as secondary endpoints. On the other hand, the use of SGLT2-i can be potentially associated with some adverse effects. However, the balance between positive and negative effects is in favor of the former. The recent results of Canagliflozin and Renal Endpoints in Diabetes with Established Nephropathy Clinical Evaluation Study and of other trials specifically testing these drugs in the population with chronic kidney disease, either diabetic or non-diabetic, do contribute to further improving our knowledge of these antihyperglycemic drugs. Here, we review the current state of the art of SGLT2-i by addressing all aspects of therapy, from the pathophysiological basis to clinical effectiveness.

Analysis of Nationwide Data to Determine the Incidence and Diagnosed Prevalence of Autosomal Dominant Polycystic Kidney Disease in the USA: 2013-2015

BACKGROUND

This study addresses an important gap, as it is the first US nationwide, epidemiologic study of ADPKD incidence and prevalence.

SUMMARY

This 3-year, observational study utilized data from Truven Health MarketScan® administrative claims, as well as cross-sectional data from the National Ambulatory Medical Care Survey (NAMCS). We estimated the annual incidence and diagnosed prevalence using population-based data on over 170 million de-identified patients to provide the most current epidemiologic estimates available. The ADPKD-diagnosed prevalence was 4.3 per 10,000 in the NAMCS, which closely corresponded with age-adjusted rates from patients with either commercial insurance or employer-sponsored Medicare supplemental insurance. The annual incidence was 0.62 per 10,000. Both nationwide data sets indicate that approximately 140,000 patients are currently diagnosed in the USA. We also found significant differences by gender and age. Females are nearly twice as likely as males to be diagnosed in early adulthood, while the incidence in males was highest in those aged 65 years or older. ADPKD appears more likely to be diagnosed in men after disease progression or the development of chronic kidney disease.

KEY MESSAGES

Our results revealed striking age and gender differences in the incidence of ADPKD. Young women are diagnosed with ADPKD at nearly twice the rate of young men, perhaps due to the use of ultrasound in women during child-bearing years. This points to a need for increased recognition of ADPKD, with an emphasis on younger men in particular. ADPKD has been inaccurately perceived as a common condition based on misinterpretation of early epidemiologic data (1957) confirmed by our data and recent European data. ADPKD affects approximately 140,000 patients in the USA and meets the criterion for a rare disease. Our results indicate a need for further study of gender and ADPKD diagnosis, progression, management, and outcomes.

Comparing outcomes of biopsy-proven anti-neutrophil cytoplasmic autoantibody-associated glomerulonephritis patients treated with cyclophosphamide in the 20th and 21st centuries: a 23-year study

Background

Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) is a multisystem autoimmune disorder associated with significant morbidity and mortality. Approximately 80–90% of patients have circulating ANCAs. Long-term outcomes appear to be improving. This retrospective study analyses the incidence and patient outcomes over a period of 23 years at a single tertiary centre.

Methods

Outcomes of patients diagnosed with AAV between 1 January 1988 and 31 December 2010 were collected retrospectively. Data including patient demographics, age of diagnosis, dates of starting renal replacement therapy, death and biochemistry results were collected. Patients were divided into two cohorts (1988–99 and 2000–10) and analysed using Stata software (StataCorp, College Station, TX, USA).

Results

A complete dataset was obtained for 273 patients. Of these patients, 101 were diagnosed between 1988 and 1999 while 172 were diagnosed between 2000 and 2010. The number of patients diagnosed with AAV increased from 2.2/million in 1988 to 10.3/million in 2010. A higher proportion of patients (56.4%) in the earlier cohort presented with creatinine >500 μmol/L compared with the later cohort (30.2%; P < 0.001). Overall patient survival improved significantly between the two cohorts. Cohort 1 had a median survival of 59 months compared with 125 months for Cohort 2 (P = 0.003).

Conclusions

This study shows that AAV is being diagnosed at an earlier stage, resulting in improved outcomes. This may be because of improvements in the management of AAV and chronic kidney disease.

Calcineurin Inhibitors With Reduced-Dose Steroids as First-Line Therapy for Focal Segmental Glomerulosclerosis

Introduction

High-dose corticosteroids remain the first-line therapy for focal and segmental glomerulosclerosis (FSGS), whereas calcineurin inhibitors (CNIs) are reserved for those patients resistant to corticosteroid therapy.

Methods

This is a retrospective cohort analysis in patients with primary FSGS diagnosed between 2007 and 2014. According to the administered treatment, patients were segregated into 3 groups: high-dose prednisone, first-line CNIs plus low-dose prednisone, and rescue CNIs. Cumulative corticosteroid doses were compared as well as response to therapy and long-term renal survival by Cox regression analysis.

Results

A total of 66 patients were included (39 treated with high-dose prednisone, 11 treated with first-line CNI, 16 treated with high-dose prednisone followed by rescue CNI). Cumulative doses of prednisone in the high-dose group were 9.3 g (interquartile range [IQR] = 7.5−12.5 g), compared to 2.5 g (IQR = 1.82−3.12 g) in the first-line CNI plus low-dose corticosteroid group and 13.8 g (IQR = 9.2−15.8 g) rescue CNI groups, respectively (P < 0.001). Time under corticosteroid management was also higher in the high-dose prednisone group compared to the first-line CNI group. There was a response to treatment in 76.9%, 72.7%, and 87.5% of high-dose prednisone, first-line CNI and rescue CNI groups, with complete remission in 48.7%, 36.4%, and 31.3% respectively. There was no difference in relapse incidence after treatment (48.4%, 44.4%, and 46.7%) or in 5-year renal survival (87.2%, 81.8%, and 87.5%). Baseline proteinuria, biopsy chronicity score, and response to therapy were independent predictors of renal survival.

Conclusion

An initial CNI plus low-dose corticosteroid approach in primary FSGS reduces corticosteroid exposure with a response-to-therapy rate similar to that of the currently recommended high-dose corticosteroid regimen. These findings justify a randomized trial to formally test this hypothesis.

Glucocorticoids in the treatment of patients with primary focal segmental glomerulosclerosis and moderate proteinuria

BACKGROUND

To compare the efficacy of glucocorticoids in primary focal segmental glomerulosclerosis (pFSGS) patients with moderate proteinuria. Registered at http://www.chictr.org.cn/ , study No. ChiCTR-OPN-17012789.

METHODS

pFSGS patients with urine protein between 1.0 and 3.5 g/24 h were recruited from 2006 to 2016. No decline in urine protein > 50% was observed after 2 months of run-in angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (ACEI/ARB) treatment. Patients were assigned to study group (glucocorticoids with ACEI/ARB) or control group (ACEI/ARB without glucocorticoids). Variables including 24-h urinary protein, serum albumin and serum creatinine during the trial were recorded. Remission was defined as proteinuria < 0.3 g/24 h or declined > 50%, and our composite end point as > 30% decrease of eGFR or eGFR < 30 ml/min.

RESULTS

A total of 102 patients were enrolled (study group N = 52, control group N = 50), and the median follow-up time was 36 (12-117) months without significant difference between groups. During the 12-month follow-up, the remission rate was significantly higher in study group [73.1 vs 50.0% (P = 0.01)], and the initial median response time was 3 months in the study group while 6 in the control group. The end point was reached by 22.2% cases in study group, and 42.0% in control. The medium survival times were study group 72 months and control 57 (P = 0.03). Minor adverse reactions were observed in 10 patients (study group N = 8, control group N = 2).

CONCLUSIONS

Additional glucocorticoids therapy is more efficacious compared to ACEI/ARB alone in the treatment of patients with pFSGS and moderate proteinuria.

Improved survival with renal transplantation for end-stage renal disease due to granulomatosis with polyangiitis: data from the United States Renal Data System

BACKGROUND

Renal transplantation is the optimal treatment for selected patients with end-stage renal disease (ESRD). However, the survival benefit of renal transplantation among patients with ESRD attributed to granulomatosis with polyangiitis (GPA) is unknown.

METHODS

We identified patients from the United States Renal Data System with ESRD due to GPA (ESRD-GPA) between 1995 and 2014. We restricted our analysis to waitlisted subjects to evaluate the impact of transplantation on mortality. We followed patients until death or the end of follow-up. We compared the relative risk (RR) of all-cause and cause-specific mortality in patients who received a transplant versus non-transplanted patients using a pooled logistic regression model with transplantation as a time-varying exposure.

RESULTS

During the study period, 1525 patients were waitlisted and 946 received a renal transplant. Receiving a renal transplant was associated with a 70% reduction in the risk of all-cause mortality in multivariable-adjusted analyses (RR=0.30, 95% CI 0.25 to 0.37), largely attributed to a 90% reduction in the risk of death due to cardiovascular disease (CVD) (RR=0.10, 95% 0.06-0.16).

DISCUSSION

Renal transplantation is associated with a significant decrease in all-cause mortality among patients with ESRD attributed to GPA, largely due to a decrease in the risk of death to CVD. Prompt referral for transplantation is critical to optimise outcomes for this patient population.

End-Stage Renal Disease and Mortality Outcomes Across Different Glomerulonephropathies in a Large Diverse US Population

OBJECTIVE

To compare renal function decline, incident end-stage renal disease (ESRD), and mortality among patients with 5 common glomerular diseases in a large diverse population.

PATIENTS AND METHODS

A retrospective cohort study (between January 1, 2000, and December 31, 2011) of patients with glomerulonephropathy using the electronic health record of an integrated health system was performed. Estimated glomerular filtration rate (eGFR) change, incident ESRD, and mortality were compared among patients with biopsy-proven focal segmental glomerulosclerosis (FSGS), membranous glomerulonephritis (MN), minimal change disease (MCD), immunoglobulin A nephropathy (IgAN), and lupus nephritis (LN). Competing risk models were used to estimate hazard ratios for different glomerulonephropathies for incident ESRD, with mortality as a competing outcome after adjusting for potential confounders.

RESULTS

Of the 2350 patients with glomerulonephropathy (208 patients [9%] younger than 18 years) with a mean follow-up of 4.5±3.6 years, 497 (21%) progressed to ESRD and 195 (8%) died before ESRD. The median eGFR decline was 1.0 mL/min per 1.73 m² per year but varied across different glomerulonephropathies (P<.001). The highest ESRD incidence (per 100 person-years) was observed in FSGS 8.72 (95% CI, 3.93-16.72) followed by IgAN (4.54; 95% CI, 1.37-11.02), LN (2.38; 95% CI, 0.37-7.82), MN (2.15; 95% CI, 0.29-7.46), and MCD (1.67; 95% CI, 0.15-6.69). Compared with MCD, hazard ratios (95% CIs) for incident ESRD were 3.43 (2.32-5.08) and 2.35 (1.46-3.81), 1.28 (0.79-2.07), and 1.02 (0.62-1.68) for FSGS, IgAN, LN, and MN, respectively. No significant association between glomerulonephropathy types and mortality was detected (P=.24).

CONCLUSION

Our findings from a real-world clinical environment revealed significant differences in eGFR decline and ESRD risk among patients with 5 glomerulonephropathies. These variations in presentation and outcomes warrant different management strategies and expectations.

NephCure Accelerating Cures Institute: A Multidisciplinary Consortium to Improve Care for Nephrotic Syndrome

Introduction

NephCure Accelerating Cures Institute (NACI) is a collaborative organization sponsored by NephCure Kidney International and the University of Michigan. The Institute is composed of 7 cores designed to improve treatment options and outcomes for patients with glomerular disease: Clinical Trials Network, Data Warehouse, Patient-Reported Outcomes (PRO) and Endpoints Consortium, Clinical Trials Consulting Team, Quality Initiatives, Education and Engagement, and Data Coordinating Center.

Methods

The Trials Network includes 22 community- and hospital-based nephrology practices, 14 of which are trial-only sites. Eight sites participate in the NACI Registry, and as of October 2017, 1054 patients are enrolled with diagnoses including but not limited to focal segmental glomerulosclerosis, minimal change disease, membranous nephropathy, IgA nephropathy, and childhood-onset nephrotic syndrome. By using electronic health record data extraction, robust and efficient clinical data are captured while minimizing the burden to site-based network staff.

Results

The Data Warehouse includes her-extracted data from registry patients, PRO development data, and data from completed observational studies and clinical trials. The Clinical Trial Consulting Team provides support for trial design in rare diseases leveraging these data. The PRO and Endpoints Consortium develops shorter-term endpoints while capturing the patient-reported significance of interventions under study. The Quality Initiatives and Education/Engagement cores elevate the level of care for patients. The Data Coordinating Center manages the analysis and operations of the Institute.

Conclusion

By engaging with patients, academia, industry, and patient advocate community representatives, including our Patient Advisory Board, NACI strives for better outcomes and treatments using evidence-based support for clinical trial design.

Sex and gender differences in chronic kidney disease: progression to end-stage renal disease and haemodialysis

Sex and gender differences are of fundamental importance in most diseases, including chronic kidney disease (CKD). Men and women with CKD differ with regard to the underlying pathophysiology of the disease and its complications, present different symptoms and signs, respond differently to therapy and tolerate/cope with the disease differently. Yet an approach using gender in the prevention and treatment of CKD, implementation of clinical practice guidelines and in research has been largely neglected. The present review highlights some sex- and gender-specific evidence in the field of CKD, starting with a critical appraisal of the lack of inclusion of women in randomized clinical trials in nephrology, and thereafter revisits sex/gender differences in kidney pathophysiology, kidney disease progression, outcomes and management of haemodialysis care. In each case we critically consider whether apparent discrepancies are likely to be explained by biological or psycho-socioeconomic factors. In some cases (a few), these findings have resulted in the discovery of disease pathways and/or therapeutic opportunities for improvement. In most cases, they have been reported as merely anecdotal findings. The aim of the present review is to expose some of the stimulating hypotheses arising from these observations as a preamble for stricter approaches using gender for the prevention and treatment of CKD and its complications.

Update on Lupus Nephritis

SLE is a chronic inflammatory disease that affects the kidneys in about 50% of patients. Lupus nephritis is a major risk factor for overall morbidity and mortality in SLE, and despite potent anti-inflammatory and immunosuppressive therapies still ends in CKD or ESRD for too many patients. This review highlights recent updates in our understanding of disease epidemiology, genetics, pathogenesis, and treatment in an effort to establish a framework for lupus nephritis management that is patient-specific and oriented toward maintaining long-term kidney function in patients with lupus.

Predicting Post-Transplant Recurrence of IgA Nephropathy: The Importance of Crescents

BACKGROUND

Most studies that have assessed the predictors of recurrent IgA nephropathy (IgAN) in the renal allograft have focused on post-transplant features. Identifying high-risk pre-transplant features of IgAN is useful for counseling patients and may help in tailoring post-transplant immunosuppression.

METHODS

We investigated the pre-transplant clinical and biopsy features of 62 patients with IgAN who received transplants at Columbia University Medical Center from 2001 to 2012 and compared the characteristics and outcomes of patients with IgAN recurrence to those without recurrence. The primary outcome was time to recurrent IgAN. Secondary outcomes were a composite of doubling of creatinine or allograft failure, and recurrent IgAN as a cause of allograft dysfunction.

RESULTS

Of the 62 patients, 14 had recurrent IgAN in the allograft. Mean time to recurrence was 2.75 years. Those with recurrent disease were younger at the time of native kidney biopsy (29 vs. 41 years, p < 0.0009). Black race and Hispanic ethnicity composed a higher proportion of the recurrent disease group. On multivariable analysis, significant predictors of recurrent IgAN included age at diagnosis (hazards ratio (HR) 0.911, 95% CI 0.85-0.98), burden of crescents on native biopsy (HR 1.21 per 10% increase in crescents, 95% CI 1.00-1.47) and allograft rejection (HR 3.59, 95% CI 1.10-11.7).

CONCLUSIONS

Features of native IgAN can help predict the risk of recurrent disease in the renal allograft. In particular, immunologically active disease represented by earlier age of onset and greater burden of crescents on native biopsy is more likely to recur after transplant.

Developing Treatments for Chronic Kidney Disease in the 21st Century

Chronic kidney disease (CKD) is a lethal and rapidly increasing burden on society. Despite this, there are relatively few therapies in development for the treatment of CKD. Several recent costly phase 3 trials have failed to provide improved renal outcomes, diminishing interest in pharmaceutical investment. Furthermore, poor patient, physician, and payer awareness of CKD as a diagnosis has contributed to slow trial enrollment and successful implementation of these trials. Nevertheless, several therapeutics remain in development for the treatment of CKD, including mineralocorticoid-receptor antagonists, sodium/glucose cotransporter 2 inhibitors, anti-inflammatory drugs, and drugs that mitigate oxidative injury. Success of future CKD therapeutic trials will depend not only on improved understanding of disease pathogenesis, but also on improved trial enrollment rates, through increasing awareness of this disease by the public, policy makers, and the greater medical community.

Differences in Initial Hemodialysis Vascular Access Use Among Glomerulonephritis Subtypes in the United States

BACKGROUND

The type of vascular access used for hemodialysis affects patient morbidity and mortality. Whether vascular access types differ by glomerulonephritis (GN) subtype in the US hemodialysis population has not been investigated.

STUDY DESIGN

Cross-sectional observational study.

SETTING & PARTICIPANTS

We identified all adult (aged ≥ 18 years) patients within the US Renal Data System who initiated hemodialysis therapy from July 2005 through December 2011 with a diagnosis of end-stage renal disease attributed to any of 4 primary (focal segmental glomerulosclerosis, immunoglobulin A nephropathy [reference group], membranous nephropathy, and membranoproliferative GN) or 2 secondary (lupus nephritis and vasculitis) GN subtypes.

PREDICTOR

GN subtype.

OUTCOMES

ORs with 95% CIs for arteriovenous fistula versus central venous catheter (CVC) use and for arteriovenous graft versus CVC use were computed using multinomial logistic regression, with adjustment for demographic, socioeconomic, comorbidity, and duration of nephrology care covariates.

RESULTS

Among 29,015 patients, CVC use at initiation of hemodialysis therapy was substantially higher in patients with lupus nephritis (89.2%) or vasculitis (91.2%) compared with patients with primary GN subtypes (72.7%-79.8%). After adjustment and compared with patients with immunoglobulin A nephropathy, patients with lupus nephritis or vasculitis were as likely to have used an arteriovenous graft (ORs of 0.94 [95% CI, 0.70-1.27] and 0.80 [95% CI, 0.56-1.13], respectively) but significantly less likely to have used an arteriovenous fistula (ORs of 0.66 [95% CI, 0.57-0.76] and 0.54 [95% CI, 0.45-0.63], respectively), whereas patients with any comparator primary GN subtype were at least as likely to have used either of these 2 access types.

LIMITATIONS

Potential misclassification of exposure; residual confounding by unmeasured covariates; inability to determine causes of observed associations; lacking longitudinal data for vascular access use.

CONCLUSIONS

Significant differences in vascular access distributions at initiation of hemodialysis therapy are apparent among GN subtypes. The unacceptably high use of CVCs in patients with lupus nephritis and vasculitis is particularly concerning. Further studies are needed to identify any potentially modifiable factors underlying these findings.

Differences in initial treatment modality for end-stage renal disease among glomerulonephritis subtypes in the USA

BACKGROUND

Kidney transplantation is the preferred treatment for end-stage renal disease (ESRD), while peritoneal dialysis affords certain benefits over hemodialysis. Distributions and determinants of first ESRD treatment modality have not been compared across glomerulonephritis (GN) subtypes.

METHODS

We identified all adult (18-75 years) patients with ESRD attributed to any of six GN subtypes [focal segmental glomerulosclerosis (FSGS), IgA nephropathy (IgAN), membranous nephropathy (MN), membranoproliferative GN (MPGN), lupus nephritis (LN) and vasculitis] who were first registered in the US Renal Data System (USRDS) between 1996 and 2011. We used multinomial logistic regression--adjusting for temporal, geographic, demographic, socioeconomic and comorbid factors--to determine odds ratios (ORs) with 95% confidence intervals (CIs) for transplantation versus hemodialysis, and for peritoneal dialysis versus hemodialysis, comparing other GN subtypes to IgAN.

RESULTS

Among the 75 278 patients studied, patients with comparator GN subtypes were significantly less likely than those with IgAN to receive either transplantation or peritoneal dialysis. After adjusting for potentially confounding covariates, patients with comparator primary GN subtypes (FSGS, MN, MPGN) were at least as likely to receive transplantation [FSGS OR 0.98 (95% CI 0.93-1.15), MN OR 1.19 (95% CI 1.01-1.39), MPGN OR 1.08 (95% CI 0.93-1.26)] or peritoneal dialysis [FSGS OR 1.05 (95% CI 0.98-1.12), MN OR 1.30 (95% CI 1.18-1.43), MPGN OR 0.95 (95% CI 0.85-1.06)] as patients with IgAN. Conversely, patients with the secondary GN subtypes LN and vasculitis remained significantly less likely to receive either modality [transplantation OR 0.49 (95% CI 0.43-0.56) for LN and 0.27 (95% CI 0.22-0.34) for vasculitis, peritoneal dialysis OR 0.76 (95% CI 0.70-0.82) for LN and 0.54 (95% CI 0.48-0.60) for vasculitis].

CONCLUSIONS

Significant differences in ESRD treatment practice patterns are apparent among GN subtypes. To ensure equitable care for all patients, regardless of GN subtype, reasons for observed disparities should be elucidated and-if appropriate-eliminated.

Hypertension and Prehypertension and Prediction of Development of Decreased Estimated GFR in the General Population: A Meta-analysis of Cohort Studies

BACKGROUND

Whether blood pressure (BP) plays an independent predictive role in the onset of decreased glomerular filtration rate (GFR) remains ill-defined because existing meta-analyses have incorporated data from studies that included individuals with low GFRs at baseline. This question is critical to optimize chronic kidney disease prevention in the general population.

STUDY DESIGN

Systematic review and meta-analysis of longitudinal cohort studies.

SETTING & POPULATION

Adults from general population.

SELECTION CRITERIA FOR STUDIES

We identified in PubMed, EMBASE, and the Cochrane Library database all cohort studies evaluating the role of BP in the incidence of decreased estimated GFR (eGFR; defined as eGFR<60 mL/min/1.73 m2) in individuals without decreased kidney function at baseline.

PREDICTORS

Hypertension (BP>140/90 mmHg), prehypertension (systolic BP of 120-139 and/or diastolic BP of 80-89 mmHg), and BP as a continuous variable.

OUTCOMES

Risk for decreased eGFR reported as relative risk (RR) and 95% CI. Heterogeneity (I2) was also evaluated.

RESULTS

Data from 16 cohorts (315,321 participants) were analyzed. All studies had a Newcastle-Ottawa score in the range of 6 to 8, denoting high quality. During a mean follow-up of 6.5 years, decreased eGFR occurred in 6.6% of participants. The presence of prehypertension and hypertension increased renal risk (RRs of 1.19 [95% CI, 1.07-1.33; I2=23.8%] and 1.76 [95% CI, 1.58-1.97; I2=37.7%], respectively). Similarly, we found that every 10-mm Hg increase in systolic and diastolic BPs associated with higher risk for decreased eGFR (RRs of 1.08 [95% CI, 1.04-1.11; I2=60.0%] and 1.12 [95% CI, 1.04-1.20; I2=51.4%], respectively). Metaregression analysis showed greater risk with older age (P=0.03), whereas other covariates were not significant.

LIMITATIONS

No individual patient-level data.

CONCLUSIONS

Prehypertension and hypertension, as BP levels, are independent predictors of decreased GFR in the general population, with the effect being more pronounced in the elderly. These findings are important for improving risk stratification in the general population.