US Renal Data System 2015 Annual Data Report: Epidemiology of Kidney Disease in the United States

Anxiety as a mediator between symptom distress and quality of life in peritoneal dialysis patients: insights from mediation analysis and nonlinear models

OBJECTIVES

This study investigates anxiety's role as a mediator between symptom burden and quality of life in patients undergoing peritoneal dialysis, emphasizing the potential for targeted interventions to enhance patient outcomes.

METHODS

In a cross-sectional design, 320 peritoneal dialysis patients were recruited, with 305 providing valid responses (response rate: 95.31%). Symptom burden (occurrence and distress), anxiety levels, and quality of life were measured using validated tools. Multiple linear regression and restricted cubic spline models assessed associations, using β with a 95% confidence interval (95% CI), while mediation analysis with 1000 bootstrap samples quantified anxiety's mediating effects.

RESULTS

Participants reported an average of 8.2 ± 2.3 concurrent symptoms, with 'worry,', 'tiredness', and 'dry skin' being the most severe. Both symptom number (β = -0.90; 95%CI: -1.26 to -0.55) and distress (β = -1.20; 95%CI: -1.41 to -0.98) negatively correlated with quality of life. Anxiety mediated these relationships significantly, explaining 38.9% (95%CI: 18%-62%) and 33.3% (95%CI: 19%-49%) of the total effects for symptom number and distress, respectively. Restricted cubic spline models revealed an 'L-shaped' relationship between symptom burden and quality of life.

CONCLUSIONS

Anxiety significantly mediates the relationship between symptom burden and quality of life in peritoneal dialysis patients. These findings underline the importance of integrating psychological interventions and routine symptom screening into patient care to enhance quality of life. Future research should explore longitudinal designs and standardized intervention strategies.

Survival and hospitalization in home versus Institutional hemodialysis-nine years of follow up

Increasing interest in home dialysis treatments are driven by better outcomes, less complications, patients desire and economic reasons. We compared 26 prevalent home hemodialysis (HHD) patients with 52 matched institutional hemodialysis patients (IHD) in survival and morbidity. Median age for HHD and IHD patients was 55,7 and 56 years respectively, and 77% were men. HHD patients had significantly better anemia control (Hgb level 12.2 ± 1.7 vs. 10.8 ± 1.3gr/dl; p = 0,001 respectively), and significantly higher albumin and cholesterol levels than IHD (42.5 ± 2 vs. 39 ± 3 g/l, p = 0.001; 5.1 ± 1 vs.4.7 ± 0.8 mmol/l, p = 0.05, respectively). During the nine years of follow up, there was no difference between groups in overall number of hospitalization (3.7 ± 3.3 vs. 3.9 ± 2.8; p = 0.47), nor in annual admission rate for everyone cause (0.5 ± 0.4 vs. 0.6 ± 0.4, p = 0.28), but IHD patients stayed longer in hospital (7.4 ± 9.8 days vs. 9.3 ± 8.7 days; p = 0.05). Cause-specific morbidity showed that IHD patients had more frequent annual admission rate for cardiovascular diseases (CVD) than HHD (0.4 ± 0.3 vs. 0.2 ± 0.1 respectively, p = 0.05), while there were no differences for infections (0.3 ± 0.3 vs. 0.3 ± 0.2 respectively, p = 0.9) nor vascular access (VA) dysfunction (0.4 ± 0.3 vs. 0.3 ± 0.3 respectively, p = 0.3). Also annual in-hospital stay for CVD (3.0 ± 3.1 vs. 4.0 ± 4.5 days; p = 0.5), infection (6,4 ± 7,5 vs. 5,7 ± 7,6 days; p = 0,6) and VA dysfunction (6.0 ± 7.0 vs. 7.7 ± 7.8 days; p = 0,5) did not differ between HHD and IHD group. As revealed by Kaplan Meier curve, survival in HHD and IHD patients were 92.3% vs. 90.4% at 3 years, 84.6% vs. 70.2% at 5 years, and 55.7% vs. 50% at 9 years (log-rank test p = 0,5). HHD provides better anemia and nutrition control; shorter hospitalizations and less frequent hospitalizations for CVD.

Acute Kidney Injury and Chronic Kidney Disease Associated with a Genetic Defect: A Report of Two Cases

Rhabdomyolysis is one of the leading causes of acute kidney injury (AKI) and is infrequently associated with chronic kidney disease (CKD). CKD appears in diabetes mellitus and arterial hypertension, as a result of other systemic diseases and glomerulonephritis. In this study, we present two cases (one with CKD and one with AKI) that are caused by a genetic defect. A genetic examination was performed in both patients, proving that the patient with CKD has a genetic defect in the RYR1 gene, which is observed in patients with malignant hyperthermia. Meanwhile, the patient with AKI has a homozygous pathogenic variant in SLC2A9, which is associated with urinary urate wasting and is characterized by asymptomatic hypouricemia and AKI after exercise. The first case is chronic rhabdomyolysis, as the patient is an athlete and performs heavy daily exercise. The second case is AKI without prior kidney damage or symptoms. Both patients did not undergo a kidney biopsy. In the first case, changes in daily routine without extreme physical exercise led to the recovery of normal kidney function. The second patient recovered from AKI without sequelae. These two cases are an example of "thinking outside the box" with respect to how genetic diseases and defects can cause kidney damage, both chronic and acute.

The Association of Fibrate Use with Kidney Outcomes and Mortality

Key Points

In this large national cohort of United States veterans followed over 14 years, fibrate was associated with a higher risk of incident CKD. Fibrate use was also associated with a lower risk of ESKD and all-cause mortality. Considering the potential long-term benefits, clinicians should not necessarily avoid fibrate use, with careful monitoring of kidney function.

Background

Fibrate use can result in an acute increase in serum creatinine, making assessing kidney outcomes associated with fibrates difficult in studies with short follow-up times. In addition, there is limited research on certain kidney outcomes and mixed results of past studies. The aim of this study was to examine the association of fibrate use with incident CKD, ESKD, and mortality in a large national cohort of United States (US) Veterans.

Methods

A retrospective cohort study was conducted to examine the association of de novo prescription of fibrate medications with incident CKD, ESKD, and mortality over up to 14 years of follow-up. Patients (N =688,382) were selected from the national Department of Veterans Affairs (VA) research database. Associations were examined in Cox proportional hazards model and Fine-Gray model adjusted for demographics, major comorbidities, laboratory measurements including baseline eGFR, albuminuria, and medications.

Results

We identified 58,773 incident new fibrate users. The overall mean (SD) age was 59 (13) years, with 7% female, 18% Black, and 7% Hispanic. Fibrate users were more likely to be male, White, current smokers, and had higher frequencies of comorbidities. In the fully adjusted model, fibrate use (versus nonuse) was associated with a lower risk of death (hazard ratio, 0.91; 95% confidential interval, 0.89 to 0.93) and ESKD (0.80, 0.71 to 0.92) but with a higher risk of incident CKD (1.21, 1.19 to 1.24).

Conclusions

In this large national cohort of US Veterans with long follow-up time, fibrate use was associated with a higher risk of incident CKD but a lower risk of ESKD and mortality. Further studies are needed to corroborate the potential benefits of fibrate on kidney function and survival.

New strategies for enhancing enrollment of underrepresented minorities in lymphoma clinical trials

ABSTRACT

New lymphoma treatments, including chimeric antigen receptor T cells, bispecific antibodies, and immune checkpoint inhibitors, have significantly improved patient outcomes. Despite these therapeutic advances, only 2% to 3% of adult patients with cancer participate in clinical trials. This participation is even lower among certain groups, including ethnic and racial minorities, individuals with low socioeconomic status, rural residents, older adults, and young adults. Underrepresentation of these groups in clinical trials limits the generalizability of trial results and is detrimental to those populations that do not receive equal access to novel therapies. Although racial and ethnic minorities constitute >40% of the US population, they make up only ∼15% of clinical trial participants. The US Food and Drug Administration now requires sponsors seeking regulatory approval for therapies via registrational clinical trials to submit a plan to ensure diversity among trial participants. This article addresses strategies for enhancing enrollment of underrepresented minorities in lymphoma clinical trials.

Nephrotic and Non-Nephrotic Focal Segmental Glomerulosclerosis: Clinical Characteristics, Etiology, and Columbia Classification

Introduction: Focal segmental glomerulosclerosis (FSGS) is a pattern of kidney injury with diverse causes and pathogeneses, resulting in podocyte injury and depletion. It can be classified as primary, genetic, or secondary. Because FSGS classically has a worse prognosis in patients with nephrotic syndrome, most studies have focused on the treatment and evolution of these patients, resulting in a lack of data related to patients without nephrotic syndrome. The objective of this study was to establish the main etiologies, characteristics, and evolution of renal disease in FSGS patients with nephrotic and non-nephrotic proteinuria. Methods: This was a retrospective, single-center study that included 140 patients with a biopsy-confirmed diagnosis of FSGS in the 2009-2017 period. Patients were separated into those with and those without nephrotic syndrome at diagnosis, and these two groups were compared in terms of the clinical characteristics, histological profile, and outcome. Non-nephrotic patients with unfavorable progression were selected for ultrastructural analysis with electron microscopy. Results: During the study period, 32.9% of the patients with FSGS had non-nephrotic proteinuria at diagnosis. This group had a larger proportion of patients with hypertension and a not otherwise specified FSGS variant on histology. The proportion of patients with secondary forms of FSGS was comparable between the two groups, with HIV infection and systemic lupus erythematosus being predominant. Progression to renal replacement therapy occurred in 31.3% of the patients in the nephrotic group and in 26.8% of those in the non-nephrotic group, with no statistical difference between them. All of the non-nephrotic group patients who progressed to renal replacement therapy were analyzed by electron microscopy, the diagnosis of FSGS was confirmed, and there was the finding of high chronicity in these patients. Conclusions: Among patients with FSGS, those without nephrotic syndrome had a poor renal outcome at a frequency similar to that of those with nephrotic syndrome. Factors related to better renal survival were having had a complete response to treatment in the case of those with nephrotic syndrome and having achieved proteinuria values of less than 1.5 g/day in the case of those without nephrotic syndrome.

A critical review of a hidden epidemic: examining the occupational and environmental risk factors of chronic kidney disease of unknown etiology (CKDu)

A form of chronic kidney disease has been described in people without any known risk factors. These cases are referred to as chronic kidney disease of an unknown etiology (CKDu).

Outcomes Following Arteriovenous Fistula Creation in Medicare Beneficiaries With End-Stage Kidney Disease

The objective of this study was to measure the contemporary patency rates and frequency of interventions required for arteriovenous fistula (AVF) care in a representative US population of patients with end-stage kidney disease, including by age, race, and gender. All Medicare beneficiaries aged >20 years who underwent AVF graft creation for end-stage kidney disease between 2017 and 2019 were included for analysis. The primary end points included primary patency, primary assisted patency, postintervention patency, and fistula functionality up to 1 year after AVF placement. The secondary end point included admission for an associated adverse event after AVF creation. Multivariate analysis of patency rates was also assessed. Of 43,457 patients included in the analysis, the cumulative primary patency at 90 days was 68.4% and at 1 year, 31.5%. At 1 year, the primary assisted patency rate, postintervention patency, and fistula use were 70.4%, 30.2%, and 59.1%, respectively. There was no difference in primary patency rates when comparing age groups (age 40 to 59 years: hazard ratio [HR] 1.01, 95% confidence interval [CI] 0.95 to 1.06, p = 0.84 or age ≥60 years: HR 0.99, 95% CI 0.93 to 1.04, p = 0.61) with the reference of age group 20 to 39 years. Women were at greater risk of experiencing primary patency failure than were men (HR 1.16, 95% CI 1.14 to 1.20, p <0.001), and Black patients were at greater risk of experiencing primary patency failure than were White patients (HR 1.34, 95% CI 1.31 to 1.38, p <0.001). The cumulative incidence of admissions for adverse events was 32.6% at 1 year. In conclusion, our findings suggest that the real-world AVF patency rates remain low, with disproportionately low rates in women and Black patients.

Morphological data of the superior vena cava predicted by multiple linear regression equations

This study explores the main surface markers in the hemodialysis puncture catheterization pathway and the relative spatial position of venous vessels in the puncture results, providing data support for venous puncture. Seventy cadavers were studied; angles of vertical axis with superior vena cava, left and right brachiocephalic vein at the confluence and circumference of superior vena cava were the primary parameters. Bivariate correlation analysis was used to determine in relation to other body parameters, and a regression equation was also obtained. The angle of the vertical axis with the superior vena cava at the confluence was linearly correlated with the distances between the coracoid processes and the jugular notch to coracoid processes. The angle of the vertical axis with left brachiocephalic vein was linearly correlated with the thickness of thorax and the length from the upper pericardial margin to the confluence. The angle of the vertical axis with right brachiocephalic vein was correlated with clavicular midline length, acromial distance, intersection point of clavicle to clavicular midline, confluence to clavicular midline, superior edge of the blood vessels to superior edge of clavicle at the right intersection, and superior edge of pericardium to confluence. There is a linear relationship between the superior vena cava circumference and the distance from the superior vena cava to the aorta. A number of parameters influence angles of the vertical axis with superior vena cava, left and right brachiocephalic veins and the superior vena cava circumference which can provide guidance for intubation.

Machine learning model and nomogram to predict the risk of heart failure hospitalization in peritoneal dialysis patients

INTRODUCTION

The study presented here aimed to establish a predictive model for heart failure (HF) and all-cause mortality in peritoneal dialysis (PD) patients with machine learning (ML) algorithm.

METHODS

We retrospectively included 1006 patients who initiated PD from 2010 to 2016. XGBoost, random forest (RF), and AdaBoost were used to train models for assessing risk for 1-year and 5-year HF hospitalization and mortality. The performance was validated using fivefold cross-validation. The optimal ML algorithm was used to construct the models to predictive the risk of the HF and all-cause mortality. The prediction performance of ML methods and Cox regression was compared.

RESULTS

Over a median follow-up of 49 months. Two hundred and ninety-eight patients developed HF required hospitalization; 199 patients died during the follow-up. The RF model (AUC = 0.853) was the best performing model for predicting HF, and the XGBoost model (AUC = 0.871) was the best model for predicting mortality. Baseline moderate or severe renal disease, systolic blood pressure (SBP), body mass index (BMI), age, Charlson Comorbidity Index (CCI) score were strongly associated with HF hospitalization, whereas age, CCI score, creatinine, age, high-density lipoprotein cholesterol (HDL-C), total cholesterol, baseline estimated glomerular filtration rate (eGFR) were the most significant predictors of mortality. For all the above endpoints, the ML models demonstrated better discrimination than Cox regression.

CONCLUSIONS

We developed and validated a novel method to predict the risk factors of HF and all-cause mortality that integrates readily available clinical, laboratory, and electrocardiographic variables to predict the risk of HF among PD patients.

"Predicting diabetic kidney disease in youth with type 1 diabetes: Insights from genetic risk assessment"

OBJECTIVE

Diabetic kidney disease (DKD) is influenced by multiple factors, yet its precise progression mechanisms remain largely unclear. This study aimed to create a clinical risk-scoring system based on genetic polymorphisms in the AFF3, CARS, CERS2, ERBB4, GLRA3, RAET1L, TMPO, and ZMIZ1 genes.

METHODS

The study included a DKD group diagnosed with diabetic kidney disease before age 18 and a WDC group matched by age, gender, and age at diabetes diagnosis. Genetic data and clinical data from diabetes diagnosis to moderately increased albuminuria (MIA) detection were compared between the groups.

RESULTS

Among 43 DKD cases, 22 were girls and 21 were boys. At MIA diagnosis, mean body weight SDS was -0.24 ± 0.94, height SDS was 0.34 ± 1.15, and BMI SDS was -0.26 ± 0.94. Systolic blood pressure was at the 72nd percentile (2-99), and diastolic blood pressure was at the 74th percentile (33-99). Significant differences in rs267734, rs267738, and rs942263 polymorphisms were found between DKD and non-complication diabetic groups (13[30.2 %] vs 5[11.6 %], p = 0.034; 14[32.6 %] vs 5[11.6 %], p = 0.019; 26[60.5 %] vs 40[93 %], p < 0.001).

CONCLUSION

Several factors were identified as significant in DKD onset, including low follow-up weight SDS, elevated diastolic blood pressure, presence of rs267734, and absence of rs942263 polymorphisms. The model demonstrated a specificity of 81.4 % and a sensitivity of 74.4 %.

Acute Kidney Disease in Oncology: A New Concept to Enhance the Understanding of the Impact of Kidney Injury in Patients with Cancer

BACKGROUND

Cancer patients are prone to developing acute kidney disease (AKD), yet this phenomenon remains understudied compared to acute kidney injury (AKI). AKD, which often develops insidiously, can cause treatment interruptions, extended hospital stays, and increased mortality.

SUMMARY

This perspective article explores the intricate relationship between AKD and cancer, focusing on prevalence, risk factors, implications for anticancer therapy, and long-term outcomes, including chronic kidney disease progression.

KEY MESSAGES

To emphasize the importance of early detection and intervention, this work advocates for increased research and awareness among clinicians to improve patient outcomes and manage healthcare burdens associated with AKD in cancer patients.

Effect of trace elements and nutrients on diabetes and its complications: a Mendelian randomization study

Background

Multiple clinical studies have observed a close relationship between serum trace elements and nutrients and diabetes and its complications, but it remains unclear whether there is a genetic causal effect between serum trace elements and nutrients and diabetes and its complications.

Objective

This study aims to investigate the causal effects of serum trace elements and nutrients on diabetes and its complications using Mendelian randomization methods.

Methods

The single nucleotide polymorphisms of serum trace elements and vitamins, as exposure factors, were sourced from the published UK Biobank database and public databases of genome-wide association studies. The genome-wide association study data of diabetes and its complications, as outcome events, were sourced from the FinnGen Biobank database. Mendelian randomization methods were employed to explore the causal relationships between 9 trace elements and 6 nutrients and diabetes and its complications. The causal relationships were inferred using inverse variance weighting, MR Egger, weighted median, simple model, and weighted model methods. Sensitivity analyses, including heterogeneity tests, horizontal pleiotropy tests, MR-PRESSO tests, and leave-one-out analysis, were conducted to evaluate the robustness of the study results. Finally, trace elements and nutrients with statistical significance in the IVW method and consistent Beta and OR directions in the five methods were selected as exposure factors with causal relationships with diabetes and its complications. This study also used multivariable Mendelian randomization methods to assess the combined effects of multiple exposure factors on the risk of diabetes and its complications.

Results

Mendelian randomization analysis revealed that selenium was linked to an elevated risk of T2D.Vitamin B6 was correlated with an increased risk of neurological complications in type 2 diabetes. Magnesium exhibited a negative causal relationship with the risk of T1D.Carotene was linked to a higher risk of renal complications in T1D.Vitamin B12 showed a negative causal relationship with renal complications in T1D.Carotene was connected to a higher risk of neurological complications in T1D.Potassium and vitamin B6 exhibited negative causal relationships with neurological complications in T1D.Vitamin E showed a negative causal relationship with peripheral circulation complications in T2D.Multivariable Mendelian randomization analysis suggested that vitamin B6 could independently influence neurological complications in both T1D and T2D, apart from other exposure factors. Vitamin B6 could also independently influence renal complications in T1D.Vitamin E could independently influence peripheral circulation complications in T1D, apart from other exposure factors.

Conclusion

The findings from univariable and multivariable Mendelian randomization studies substantiate the causal relationships between trace elements and nutrients and different subtypes of diabetes and their complications. These findings hold significant clinical implications for developing targeted prevention and treatment strategies for diabetes and its complications.

Impact of chronic kidney disease and end-stage renal disease on the mid-term adverse outcomes in diabetic patients with cardiovascular diseases

The evidence for the impact of renal dysfunction in patients with diabetes mellitus (DM) and first cardiovascular diseases on mid-term adverse outcomes remain scarce. This study included the data of patients with DM having first atherosclerotic cardiovascular disease (ASCVD) or congestive heart failure (CHF) from the Taipei Medical University Clinical Research Database. A Cox proportional hazards regression model was used to assess the impact of chronic kidney disease (CKD) or end-stage renal disease (ESRD) on the 1-year mortality and recurrent ASCVD/CHF outcomes. We enrolled 21,320 patients with DM hospitalized for ASCVD or CHF; of them, 18,185, 2639, and 496 were assigned to the non-CKD, CKD, and ESRD groups, respectively. After propensity score matching, compared with the non-CKD group, the CKD and ESRD groups had higher mid-term all-cause mortality (adjusted hazard ratio 1.72 [95% confidence interval 1.48-1.99] and 2.77 [2.05-3.73], respectively), cardiovascular death (1.84 [1.44-2.35] and 1.87 [1.08-3.24], respectively), and recurrent hospitalization for ASCVD (1.44 [1.24-1.68] and 2.33 [1.69-3.23], respectively) and CHF (2.08 [1.75-2.47] and 1.50 [1.04-2.17], respectively). The advancing age was associated with mortality in CKD/ESRD groups. In CKD group, male sex was associated with all-cause mortality and recurrent ASCVD risk; the diuretics usage was associated with mortality and recurrent CHF risks. Our findings suggest that CKD and ESRD are significant risk factors for mid-term adverse outcomes in patients with DM and established cardiovascular diseases. Additionally, old age, male sex and diuretics usage requires attention. Further good quality studies are needed in the future.

Beta-blocker efficacy for intra- and interdialytic hypertension patients: a systematic review and meta-analysis

PURPOSE

Intradialytic hypertension affects 5-15% of hemodialysis patients, yet relevant studies are relatively scarce. It is also associated with higher interdialytic blood pressure. Beta-blockers can be preferred as antihypertensive drugs due to their superior blood pressure control, decreased risk of cardiovascular events, improved endothelial cell function, and decreased noradrenaline levels. Through this study, beta-blocker antihypertensive effects in intra- and interdialytic hypertension were analyzed.

METHODS

Systematic review and meta-analysis were performed following PRISMA guidelines. We registered our PROSPERO protocol (Registration ID: CRD42023446184) and included relevant full-text clinical trials or RCTs from 2008 to 2023 with predetermined keywords and criteria from multiple databases including PUBMED, COCHRANE, SCOPUS, and citation searching. Seven eligible articles were included in this review study.

RESULTS

Four studies with 82 participants for intradialytic hypertension evaluation were included. Meta-analysis showed a decrease in SBP in intradialytic hypertensive patients after beta-blocker intervention, with a significant estimated mean difference of - 15.19 mmHg (P < 0.00001; 95% CI - 19.47 to - 10.91). Supporting previous data, SBP remains constant between pre- and post-dialysis with beta-blocker therapy, with an insignificant estimated mean difference of - 2.72 mmHg (P = 0.29; 95% CI - 7.80 to 2.36). Whereas five studies with 142 participants were included for interdialytic hypertension evaluation. Meta-analysis shows a significant decrease in SBP before to after therapy, with an estimated mean difference of - 10.92 (P < 0.0001; 95% CI - 16.33 to - 5.51).

CONCLUSION

Beta-blocker treatment resulted in significant reductions in post-hemodialysis systolic blood pressure among intra- and interdialytic hypertensive patients.

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.

Proneurotensin/Neuromedin N and Risk of Incident CKD and Other Kidney Outcomes in Community-Living Individuals: The REGARDS Study

Rationale & Objective

Plasma proneurotensin/neuromedin N (pro-NT/NMN) is a precursor of neurotensin, a tridecapeptide linked with type 2 diabetes mellitus and other comorbid conditions associated with kidney disease. Whether pro-NT/NMN is directly associated with incident chronic kidney disease (CKD), and whether that association differs by race, is uncertain. We evaluated whether pro-NT/NMN levels were associated with increased risk of kidney outcomes.

Study Design

Prospective cohort.

Setting & Participants

Participants in Biomarker Mediators of Racial Disparities in Risk Factors, a nested cohort from the REasons for Geographic And Racial Differences in Stroke study, with available stored serum and urine samples from baseline and second visits for biomarker measurement.

Exposure

Baseline log-transformed pro-NT/NMN.

Outcomes

Incident CKD, progressive estimated glomerular filtration rate (eGFR) decline, incident albuminuria, and incident kidney failure within median follow-up time of 9.4 years.

Analytical Approach

Logistic regression.

Results

Among 3,914 participants, the mean ± SD age was 64 ± 8 (SD) years, 48% were women, and 51% were Black. Median baseline eGFR was 90 (IQR, 77-102) mL/min/1.73 m2. Each SD higher of pro-NT/NMN was associated with 9% higher odds of progressive eGFR decline (OR, 1.09; 95% CI, 1.00-1.20). There was no association observed with incident CKD (OR, 1.10; 95% CI, 0.96-1.27), incident albuminuria (OR, 1.08; 95% CI, 0.96-1.22), or incident kidney failure (OR, 1.10; 95% CI, 0.83-1.46). There were no differences in results by race or sex.

Limitations

Single measurement of pro-NT/NMN and limited generalizability.

Conclusions

Higher pro-NT/NMN was associated with progressive eGFR decline but no other manifestations of kidney disease incidence.

Cardioprotective effect of intradialytic exercise on left atrial mechanics

Left atrial (LA) function plays a pivotal role in cardiac performance by modulating left ventricular (LV) function. Impairments in LV function are commonly reported during hemodialysis (HD), but available data describing changes in LA function are limited. There is growing evidence of the cardioprotective effect of intradialytic exercise (IDE) on LV function, but studies analyzing its effect on LA function are scarce. Our aim was to evaluate whether IDE can limit the severity of HD-induced impairment in LA myocardial function. In this prospective, open-label, two-center randomized crossover trial, 56 stable individuals receiving HD participated in 2 HD sessions in random order: standard HD and a session incorporating 30 min of aerobic exercise. LA and LV global longitudinal strains (GLSs) were obtained before and at peak stress of HD (i.e., 30 min before the HD ending). IDE totally eradicated the decline in LA reservoir strain observed during HD (estimated difference: 3.1%, 95% confidence interval: 0.4/5.8, P = 0.02), whereas it did not affect the other components of LA mechanics. A similar result favoring IDE intervention was also demonstrated on GLS changes over the HD procedure (P < 0.001). Between-session differences of changes in GLS and LA reservoir strain were correlated (r = -0.32, P = 0.03). The cardioprotective effect of IDE disappeared in patients with LA enlargement (i.e., LA volume index >34 mL/m2). In conclusion, even a short duration of IDE at moderate intensity is effective in preventing HD-associated decline in LA reservoir function. Further research is needed to explore the long-term benefits of IDE on LA function.NEW & NOTEWORTHY A single bout of intradialytic exercise (IDE) at moderate intensity can prevent the hemodialysis-associated decline in left atrial (LA) function. This was partially explained by the relative preservation of left ventricular systolic function with IDE. Benefits of IDE on LA function were lost in patients with LA dilation. Further studies are needed to explore the mechanisms behind IDE-induced cardioprotection and evaluate the clinical impacts of the repetitive cardioprotective effects of IDE on LA function.

A clustering approach to improve our understanding of the genetic and phenotypic complexity of chronic kidney disease

Chronic kidney disease (CKD) is a complex disorder that causes a gradual loss of kidney function, affecting approximately 9.1% of the world's population. Here, we use a soft-clustering algorithm to deconstruct its genetic heterogeneity. First, we selected 322 CKD-associated independent genetic variants from published genome-wide association studies (GWAS) and added association results for 229 traits from the GWAS catalog. We then applied nonnegative matrix factorization (NMF) to discover overlapping clusters of related traits and variants. We computed cluster-specific polygenic scores and validated each cluster with a phenome-wide association study (PheWAS) on the BioMe biobank (n = 31,701). NMF identified nine clusters that reflect different aspects of CKD, with the top-weighted traits signifying areas such as kidney function, type 2 diabetes (T2D), and body weight. For most clusters, the top-weighted traits were confirmed in the PheWAS analysis. Results were found to be more significant in the cross-ancestry analysis, although significant ancestry-specific associations were also identified. While all alleles were associated with a decreased kidney function, associations with CKD-related diseases (e.g., T2D) were found only for a smaller subset of variants and differed across genetic ancestry groups. Our findings leverage genetics to gain insights into the underlying biology of CKD and investigate population-specific associations.

Show Me CKDintercept Initiative: A Collective Impact Approach to Improve Population Health in Missouri

Ninety percent of people with chronic kidney disease (CKD) remain undiagnosed, most people at risk do not receive guideline-concordant testing, and disparities of care and outcomes exist across all stages of the disease. To improve CKD diagnosis and management across primary care, the National Kidney Foundation launched a collective impact (CI) initiative known as Show Me CKDintercept. The initiative was implemented in Missouri, USA from January 2021 to June 2022, using a data strategy, stakeholder engagement and relationship mapping, learning in action working groups (LAWG), and a virtual leadership summit. The Reach, Effectiveness, Adoption, Implementation, and Maintenance framework was used to evaluate success. The initiative united 159 stakeholders from 81 organizations (Reach) to create an urgency for change and engage new CKD champions (Effectiveness). The adoption resulted in 53% of participants committed to advancing the roadmap (Adoption). Short-term results reported success in laying a foundation for CI across Missouri. The long-term success of the CI initiative in addressing the public health burden of kidney disease remains to be determined. The project reported the potential use of a CI initiative to build leadership consensus to drive measurable public health improvements nationwide.

A pragmatic approach to selective genetic testing in kidney transplant candidates

Introduction

Advances in the field of genetic testing have spurred its use in transplantation. Potential benefits of genetic testing in transplant nephrology include diagnosis, treatment, risk stratification of recurrent disease, and risk stratification in potential donors. However, it is unclear how to best apply genetic testing in this population to maximize its yield. We describe our transplant center's approach to selective genetic testing as part of kidney transplant candidate and donor evaluation.

Methods

Transplant recipient candidates were tested if they had a history of ESRD at age <50, primary FSGS, complement-mediated or unknown etiology of kidney disease, or had a family history of kidney disease. Donors were tested if age <35, were related to their potential recipients with known genetic susceptibility or had a first-degree relative with a history of kidney disease of unknown etiology. A targeted NGS gene panel of 385 genes was used. Clinical implications and downstream effects were monitored.

Results

Over 30% of recipients tested within the established criteria were positive for a pathogenic variant. The most common pathogenic variants were APOL1 high-risk genotypes as well as collagen 4-alpha-3, -4 and -5. Donor testing done according to our inclusion criteria resulted in about 12% yield. Positive test results in recipients helped with stratification of the risk of recurrent disease. Positive test results in potential donors guided informed decisions on when not to move forward with a donation.

Discussion

Integrating targeted panel genetic testing into a kidney transplant clinic in conjunction with a selective criteria for testing donors and recipients ensured a reasonable diagnostic yield. The results had implications on clinical management, risk stratification and in some cases were instrumental in directing downstream changes including when to stop the evaluation process. Given the impact on management and transplant decisions, we advocate for the widespread use of genetic testing in selected individuals undergoing transplant evaluation and donation who meet pre-defined criteria.

Kidney Biopsy and Immuno-Rheumatological Diseases: A Retrospective and Observational Study

Renal involvement is a common occurrence in patients with immuno-rheumatological diseases (IRDs). Several instances of glomerulonephritis (GN) occur in the setting of IRD and complicate the clinical course of an underlying condition. The aim of this study was to observe the spectrum of nephropathies according to age, kidney function, history of IRD at the time of biopsy, and histopathological kidney diagnosis. We evaluated data relating to 699 consecutive kidney native biopsies (female 52.1%) with a median age of 48 years (IQR 34-62) performed in adult patients collected over 15 years. The study population was divided into three groups: patients with kidney histological findings correlated to underlying IRD (Group 1), patients with kidney histological findings not correlated to underlying IRD (Group 2), and patients with kidney histological findings compatible with "de novo" IRD (absent in personal medical history) (Group 3). Kidney involvement related to IRD was found in 25.2% of patients. Group 1 was mostly represented by lupus nephritis (76.6%), with a younger age than Group 3 (p < 0.001) and by a higher percentage of females than other groups (p < 0.001). Group 3 was the most represented by microscopic polyangiitis (50.8%) when compared with the other two groups (p < 0.001). Acute nephritic syndrome (p < 0.001), acute kidney injury (AKI), and abnormal urinalysis (p < 0.001) were more represented in Group 3 than the other groups. In conclusion, IRDs are characterized by different clinical presentations and heterogeneous histological findings. Kidney biopsy remains fundamental to achieving the correct diagnosis and starting targeted therapy.

Comparative analysis of hospitalizations among patients treated with hemodialysis and peritoneal dialysis in European pediatric nephrology centers: results from a prospective EPDWG/ESPN Dialysis Working Group study

Background and hypothesis

Hospital admissions in pediatric dialysis patients need to be better studied, and most existing studies are retrospective and based on registry data. This study aimed to analyse and compare hospital admission rates, causes, length of stay (LOS), and outcomes in children treated with peritoneal dialysis (PD) and hemodialysis (HD).

Methods

Data from 236 maintenance PD and 138 HD patients across 16 European dialysis centers were collected between 1 July 2017 and 30 June 2018. A total of 178 hospitalized patients (103 PD, 75 HD) were included for further analyses.

Results

There were 465 hospitalization events (268 PD, 197 HD) with a rate of 0.39 admissions per 100 patient-days at risk (PDAR) and 2.4 hospital days per 100 PDAR. The admission rates were not significantly different between HD and PD patients. The most common causes of hospitalization were access-related infections (ARI) (17%), non-infectious complications of access (NIAC) (14%), and infections unrelated to access (12%). ARI was the leading cause in PD patients (24%), while NIAC was more common in HD patients (19%). PD patients had more ARIs, diagnostic procedures, and treatment adjustments (P < .05), while HD patients had more NIACs, infections unrelated to access, access placement procedures, and interventional/surgical procedures (P < .001). LOS was longer with acute admissions than non-acute admissions (P < .001). Overall LOS and LOS in the intensive care unit were similar between HD and PD patients. High serum uric acid and low albumin levels were significant predictors of longer LOS (P = .022 and P = .045, respectively). Young age, more significant height deficit, and older age at the start of dialysis were predictors of longer cumulative hospital days (P = .002, P = .001, and P = .031, respectively).

Conclusion

Access-related complications are the main drivers of hospitalization in pediatric dialysis patients, and growth and nutrition parameters are significant predictors of more extended hospital stays.

Complex central venous catheter for dialysis: interventional radiology experience in insertion and management of their complications

BACKGROUND

CVCs are defined 'complex' when they are inserted through non-conventional accesses or positioned in non-usual sites or substituted by IR endovascular procedures. We report our experience in using diagnostic and interventional radiology techniques for complex CVC insertion and management; we recommend some precautions and techniques that could lead to long-term availability of central venous access and to avoid non-conventional sites CVC insertion.

METHODS

We retrospectively evaluated 617 patients, between January 2010 and December 2019, (mean age 71 ± 13; male 448/617), treated in our department for insertion of tunnelled CVC for haemodialysis.

RESULTS

Among 617 patients, 241 cases (39%) are considered 'complex' because they required either a PTA with or without stenting to restore/maintain venous access or had an unusual positioning site or required unconventional access. A direct correlation between CT angiography and PTA (r = 0.95; p-value <0.001) and an inverse correlation between CT angiography and unconventional 'rescue' access (r = -0.92; p-value <0.001) were found.

CONCLUSIONS

Precise pre-operative planning of treatment in a multidisciplinary setting and diagnostic and interventional radiology procedures knowledge allows reducing complex catheterisms in haemodialysis patient.

MAPK1 Mediates MAM Disruption and Mitochondrial Dysfunction in Diabetic Kidney Disease via the PACS-2-Dependent Mechanism

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease (ESRD). Mitochondrial dysfunction in renal tubules, occurring early in the disease, is linked to the development of DKD, although the underlying pathways remain unclear. Here, we examine diabetic human and mouse kidneys, and HK-2 cells exposed to high glucose, to show that high glucose disrupts mitochondria-associated endoplasmic reticulum membrane (MAM) and causes mitochondrial fragmentation. We find that high glucose conditions increase mitogen-activated protein kinase 1(MAPK1), a member of the MAP kinase signal transduction pathway, which in turn lowers the level of phosphofurin acidic cluster sorting protein 2 (PACS-2), a key component of MAM that tethers mitochondria to the ER. MAPK1-induced disruption of MAM leads to mitochondrial fragmentation but this can be rescued in HK-2 cells by increasing PACS-2 levels. Functional studies in diabetic mice show that inhibition of MAPK1 increases PACS-2 and protects against the loss of MAM and the mitochondrial fragmentation. Taken together, these results identify the MAPK1-PACS-2 axis as a key pathway to therapeutically target as well as provide new insights into the pathogenesis of DKD.

Association of oral iron replacement therapy with kidney failure and mortality in CKD patients

Background

Oral iron is the predominant route of iron replacement (IRT) but its benefits and safety are unclear in patients with chronic kidney disease (CKD).

Methods

We examined the association of oral IRT vs no IRT with end-stage kidney disease (ESKD) and mortality in a national cohort of US Veterans. We identified 17 413 incident new users of oral IRT with estimated glomerular filtration rates <60 mL/min/1.73 m2 and 32 530 controls who did not receive any IRT during 2004-18. We used propensity score-overlap weighting to account for differences in key baseline characteristics associated with the use of oral IRT. We examined associations using competing risk regression and Cox models.

Results

In the cohort of 49 943 patients, 1616 (3.2%) patients experienced ESKD and 28 711 (57%) patients died during a median follow-up of 1.9 years. Oral IRT was not associated with ESKD [subhazard ratio (HR) (95% confidence interval, CI) 1.00 (0.84-1.19), P = .9] and was associated with higher risk of all-cause mortality [HR (95% CI) 1.06 (1.01-1.11), P = .01]. There was significant heterogeneity of treatment effect for mortality, with oral IRT associated with higher mortality in the subgroups of patients without congestive heart failure (CHF), anemia or iron deficiency. In patient with blood hemoglobin <10 g/dL oral IRT was associated with significantly lower mortality.

Conclusion

Oral IRT was associated with lower mortality only in patients with anemia. In patients without anemia, iron deficiency or CHF, the risk-benefit ratio of oral IRT should be further examined.

Comparison of focal segmental glomerulosclerosis and other primary glomerulonephrites in terms of parameters of hepatic steatosis and metabolic syndrome

PURPOSE

The increasing frequency of coexistence of focal segmental glomerulosclerosis (FSGS) and obesity-associated glomerulopathy and the relationship between metabolic syndrome components and chronic kidney disease have been demonstrated in studies. Based on this information, in this study, we aimed to compare FSGS and other primary glomerulonephritis diagnoses in terms of parameters of metabolic syndrome and hepatic steatosis.

MATERIALS AND METHODS

In our study, the data of 44 patients who were diagnosed FSGS through kidney biopsy and 38 patients with any other primary glomerulonephritis diagnoses in our nephrology clinic were retrospectively analyzed. Patients were divided into two groups: FSGS and other primary glomerulonephritis diagnoses, and they were examined in terms of their demographic data, laboratory parameters, body composition measurements, and the presence of hepatic steatosis, as shown using liver ultrasonography.

RESULTS

In the comparative analysis of patients with FSGS and other primary glomerulonephritis diagnoses, with the increase in age increased the risk of FSGS by 1.12 times, the increase in BMI ​​increased the risk of FSGS by 1.67 times, while with the decrease in waist circumference decreased the risk of FSGS by ​​0.88 times, the decrease in HbA1c decreased the risk of FSGS by ​​0.12 times, and the presence of hepatic steatosis increased the risk of FSGS by 20.24 times.

CONCLUSION

The presence of hepatic steatosis, an increase in waist circumference and BMI values, which are body components favoring obesity, and an increase in HbA1c, which is a marker for hyperglycemia and insulin resistance, are greater risk factors for the development of FSGS compared with other primary glomerulonephritis diagnoses.

Diagnosis of Kidney Diseases of Unknown Etiology Through Biopsy-Genetic Analysis

Introduction

Previous studies have suggested that genetic kidney diseases in adults are often overlooked, representing up to 10% of all cases of chronic kidney disease (CKD). We present data obtained from exome sequencing (ES) analysis of patients with biopsy-proven undetermined kidney disease (UKD).

Methods

ES was proposed during routine clinical care in patients with UKD from January 2020 to December 2021. We used in silico custom kidney genes panel analysis to detect pathological variations using American College of Medical Genetics guidelines in 52 patients with biopsy-proven UKD with histological finding reassessment.

Results

We detected 12 monogenic renal disorders in 21 (40.4%) patients. The most common diagnoses were collagenopathies (8/21,38.1%), COL4A3 and COL4A4 accounting for 80% of these diagnoses, and ciliopathies (5/21, 23.8%). The diagnostic yield of ES was higher in female patients and patients with a family history of kidney disease (57.1% and 71%, respectively). Clinical nephropathy categories matched with the final genetic diagnoses in 72.7% of cases, whereas histological renal lesions matched with the final diagnoses in 92.3% of cases. The genetics diagnoses and histopathological findings were in complete agreement for both glomerular and tubulointerstitial cases. Interstitial inflammation without tubulitis was only observed in tubulopathies or ciliopathies. Isolated CKD, CKD with proteinuria or hematuria, and isolated proteinuria or hematuria yielded the highest diagnostic yields (54.6%, 52.6%, and 42.9%, respectively).

Conclusion

ES done in patients with biopsy-proven UKD should be considered as a first-line tool for CKD patients with a family history of kidney disease. Combination of ES and kidney biopsy may have major impacts on kidney disease ontology.

Assessment of dysfunctional tunneled hemodialysis catheters and outcome of endovascular salvage techniques: a simple solution to a complex problem

Objective

The aim of this study was to evaluate the causes of the dysfunctional tunneled cuffed catheters (TCCs) using multi-spiral computed tomography venography (MSCTV), and to analyze the outcomes of endovascular salvage techniques.

Material and methods

This retrospective review data from 27 patients who experienced TCC dysfunction between July 1, 2016 and January 31, 2021 was conducted. Patients' demographic data, clinical signs and symptoms, and imaging data were collected from interventional radiology database.

Results

MSCTV showed a range of abnormalities in the hemodialysis (HD) patients, including central venous occlusion (n = 4), fibrin sheath formation (n = 3), malposition of the catheter tips (n = 4), central venous perforation (n = 1), thrombus formation (n = 12), regular catheter exchange without determined lesions (n = 3). Interventional catheter salvage procedures were performed, such as catheter exchange, balloon disruption of a fibrin sheath, angioplasty for central vein stenosis, and stent deployment. The technical success rate for catheter insertions was 100%, and no procedure-related severe complications were observed. The 30-day catheter patency for all assessable catheters was 85.2%.

Conclusion

The use of MSCTV showed abnormal findings in almost 88.9% of cases concerning dysfunctional TCC. In this study, the examined appropriate endovascular techniques were found to be safe and technically successful, with a low incidence of procedure-related complications.

Renal, but not platelet or skin, extracellular vesicles decrease oxidative stress, enhance nascent peptide synthesis, and protect from ischemic renal injury

Acute kidney injury (AKI) is deadly and expensive, and specific, effective therapy remains a large unmet need. We have demonstrated the beneficial effects of transplanted adult tubular cells and extracellular vesicles (EVs; exosomes) derived from those renal cells on experimental ischemic AKI, even when administered after renal failure is established. To further examine the mechanisms of benefit with renal EVs, we tested the hypothesis that EVs from other epithelia or platelets (a rich source of EVs) might be protective, using a well-characterized ischemia-reperfusion model. When given after renal failure was present, renal EVs, but not those from skin or platelets, markedly improved renal function and histology. The differential effects allowed us to examine the mechanisms of benefit with renal EVs. We found significant decreases in oxidative stress postischemia in the renal EV-treated group with preservation of renal superoxide dismutase and catalase as well as increases in anti-inflammatory interleukin-10. In addition, we propose a novel mechanism of benefit: renal EVs enhanced nascent peptide synthesis following hypoxia in cells and in postischemic kidneys. Although EVs have been used therapeutically, these results serve as "proof of principle" to examine the mechanisms of injury and protection.NEW & NOTEWORTHY Acute kidney injury is common and deadly, yet the only approved treatment is dialysis. Thus, a better understanding of injury mechanisms and potential therapies is needed. We found that organ-specific, but not extrarenal, extracellular vesicles improved renal function and structure postischemia when given after renal failure occurred. Oxidative stress was decreased and anti-inflammatory interleukin-10 increased with renal, but not skin or platelet, exosomes. We also propose enhanced nascent peptide synthesis as a novel protective mechanism.

Electronic Phenotype for Advanced Chronic Kidney Disease in a Veteran Health Care System Clinical Database: Systems-Based Strategy for Model Development and Evaluation

BACKGROUND

Identifying advanced (stages 4 and 5) chronic kidney disease (CKD) cohorts in clinical databases is complicated and often unreliable. Accurately identifying these patients can allow targeting this population for their specialized clinical and research needs.

OBJECTIVE

This study was conducted as a system-based strategy to identify all prevalent Veterans with advanced CKD for subsequent enrollment in a clinical trial. We aimed to examine the prevalence and accuracy of conventionally used diagnosis codes and estimated glomerular filtration rate (eGFR)-based phenotypes for advanced CKD in an electronic health record (EHR) database. We sought to develop a pragmatic EHR phenotype capable of improving the real-time identification of advanced CKD cohorts in a regional Veterans health care system.

METHODS

Using the Veterans Affairs Informatics and Computing Infrastructure services, we extracted the source cohort of Veterans with advanced CKD based on a combination of the latest eGFR value ≤30 ml·min-1·1.73 m-2 or existing International Classification of Diseases (ICD)-10 diagnosis codes for advanced CKD (N18.4 and N18.5) in the last 12 months. We estimated the prevalence of advanced CKD using various prior published EHR phenotypes (ie, advanced CKD diagnosis codes, using the latest single eGFR <30 ml·min-1·1.73 m-2, utilizing two eGFR values) and our operational EHR phenotypes of a high-, intermediate-, and low-risk advanced CKD cohort. We evaluated the accuracy of these phenotypes by examining the likelihood of a sustained reduction of eGFR <30 ml·min-1·1.73 m-2 over a 6-month follow-up period.

RESULTS

Of the 133,756 active Veteran enrollees at North Florida/South Georgia Veterans Health System (NF/SG VHS), we identified a source cohort of 1759 Veterans with advanced nondialysis CKD. Among these, 1102 (62.9%) Veterans had diagnosis codes for advanced CKD; 1391(79.1%) had the index eGFR <30 ml·min-1·1.73 m-2; and 928 (52.7%), 480 (27.2%), and 315 (17.9%) Veterans had high-, intermediate-, and low-risk advanced CKD, respectively. The prevalence of advanced CKD among Veterans at NF/SG VHS varied between 1% and 1.5% depending on the EHR phenotype. At the 6-month follow-up, the probability of Veterans remaining in the advanced CKD stage was 65.3% in the group defined by the ICD-10 codes and 90% in the groups defined by eGFR values. Based on our phenotype, 94.2% of high-risk, 71% of intermediate-risk, and 16.1% of low-risk groups remained in the advanced CKD category.

CONCLUSIONS

While the prevalence of advanced CKD has limited variation between different EHR phenotypes, the accuracy can be improved by utilizing two eGFR values in a stratified manner. We report the development of a pragmatic EHR-based model to identify advanced CKD within a regional Veterans health care system in real time with a tiered approach that allows targeting the needs of the groups at risk of progression to end-stage kidney disease.

Role of the CD40-CD40 Ligand Pathway in Cardiovascular Events, Neurological Alterations, and Other Clinical Complications of Chronic Hemodialysis Patients: Protective Role of Adsorptive Membranes

Despite the recent advances in dialysis technology, mortality rate of chronic uremic patients still remains excessively high: of note, in comparison to age- and sex-matched healthy controls, this frail population shows a higher incidence of infections, cancer, cognitive decline, and, in particular, major adverse cardiovascular events (MACE) that represent nowadays the first cause of mortality. Several traditional and nontraditional factors contribute to this increased risk for MACE and accelerated cellular senescence: among these, inflammation has been shown to play a key role. The costimulatory pathway CD40-CD40 Ligand (CD40L) is harmfully activated during inflammation and uremia-associated clinical complications: in particular, the soluble form of CD40L (sCD40L) can bind to the CD40 receptor triggering a cascade of detrimental pathways in immune and nonimmune cells. In this narrative review, we summarize the current concepts of the biological role of the CD40-CD40L pathway in uremia-associated organ dysfunction, focusing on the above-described main causes of mortality. Moreover, we discuss the interaction of the CD40-CD40L pathway with extracellular vesicles, microparticles recently identified as new uremic toxins. The biological effects of sCD40L in MACE, cognitive decline, infections, and cancer will be also briefly commented. Last, based on recent studies and ongoing clinical trials, we herein describe the modulatory activity of adsorptive dialysis membranes in polymethylmethacrylate on CD40-CD40L detrimental activation.

Association of Intradialytic Hypertension with Future Cardiovascular Events and Mortality in Hemodialysis Patients: Effects of Ambulatory Blood Pressure

INTRODUCTION

Intradialytic hypertension (IDHTN) is associated with increased risk of adverse outcomes. Patients with IDHTN have higher 44-h blood pressure (BP) than patients without this condition. Whether the excess risk in these patients is due to the BP rise during dialysis per se or on elevated 44-h BP or other comorbid conditions is uncertain. This study evaluated the association of IDHTN with cardiovascular events and mortality and the influence of ambulatory BP and other cardiovascular risk factors on these associations.

METHODS

242 hemodialysis patients with valid 48-h ABPM (Mobil-O-Graph-NG) were followed for a median of 45.7 months. IDHTN was defined as: systolic BP (SBP) rise ≥10 mm Hg from pre- to post-dialysis and post-dialysis SBP ≥150 mm Hg. The primary endpoint was all-cause mortality; the secondary endpoint was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, resuscitation after cardiac arrest, heart failure hospitalization, coronary or peripheral revascularization.

RESULTS

Cumulative freedom from both the primary and secondary endpoint was significantly lower for IDHTN patients (logrank-p = 0.048 and 0.022, respectively), corresponding to higher risks for all-cause mortality (hazard ratio (HR) = 1.566; 95% confidence interval (CI) [1.001, 2.450]) and the composite cardiovascular outcome (HR = 1.675; 95% CI [1.071, 2.620]) in these individuals. However, the observed associations lost statistical significance after adjustment for 44-h SBP (HR = 1.529; 95% CI [0.952, 2.457] and HR = 1.388; 95% CI [0.866, 2.225], respectively). In the final model after additional adjustment for 44-h SBP, interdialytic weight gain, age, history of coronary artery disease, heart failure, diabetes, and 44-h pulse wave velocity, the association of IDHTN with the outcomes was also not significant and the respective HRs were 1.377 (95% CI [0.836, 2.268]) and 1.451 (95% CI [0.891, 2.364]).

CONCLUSIONS

IDHTN patients had higher risk for mortality and cardiovascular outcomes but this risk is at least partly confounded by the elevated BP levels during the interdialytic period.

Current and Novel Biomarkers of Progression Risk in Children with Chronic Kidney Disease

BACKGROUND

Due to the complexity of chronic kidney disease (CKD) pathophysiology, biomarkers representing different mechanistic pathways have been targeted for the study and development of novel biomarkers. The discovery of clinically useful CKD biomarkers would allow for the identification of those children at the highest risk of kidney function decline for timely interventions and enrollment in clinical trials.

SUMMARY

Glomerular filtration rate and proteinuria are traditional biomarkers to classify and prognosticate CKD progression in clinical practice but have several limitations. Over the recent decades, novel biomarkers have been identified from blood or urine with metabolomic screening studies, proteomic screening studies, and an improved knowledge of CKD pathophysiology. This review highlights promising biomarkers associated with the progression of CKD that could potentially serve as future prognostic markers in children with CKD.

KEY MESSAGES

Further studies are needed in children with CKD to validate putative biomarkers, particularly candidate proteins and metabolites, for improving clinical management.

Management of concomitant central venous disease

Symptomatic central venous disease (CVD) is a significant common problem in patients with end-stage renal disease given its adverse impact on hemodialysis (HD) vascular access (VA). The current mainstay management is percutaneous transluminal angioplasty (PTA) with or without stenting which is typically reserved for unsatisfactory angioplasty or more challenging lesions. Despite factors such as target vein diameters and lengths and vessel tortuosity that may determine the choice of bare-metal versus covered stents (CS), current scientific literature is pointing out the superiority of the latter one. Alternative management options such as hemodialysis reliable outflow (HeRO) graft showed favorable results in terms of high patency rates and fewer infections, however, complications such as a steal syndrome and, to a lesser extent, graft migration and separation are major concerns. The surgical reconstruction approaches such as bypass, patch venoplasty, or chest wall arteriovenous graft with or without endovascular interventions as a hybrid procedure are still viable options and may be considered. However, further long-term investigations are needed to highlight the comparative outcomes of these approaches. Open surgery might be an alternative before proceeding to more unfavorable approaches such as lower extremity vascular access (LEVA). The appropriate therapy should be selected based upon a patient-centered interdisciplinary discussion utilizing the locally available expertise in the area of VA creation and maintenance.

Does anybody really know what (the kidney median waiting) time is?

The median waiting time (MWT) to deceased donor kidney transplant is of interest to patients, clinicians, and the media but remains elusive due to both methodological and philosophical challenges. We used Organ Procurement and Transplantation Network data from January 2003 to March 2022 to estimate MWTs using various methods and timescales, applied overall, by era, and by candidate demographics. After rising for a decade, the overall MWT fell to 5.19 years between 2015 and 2018 and declined again to 4.05 years (April 2021 to March 2022), based on the Kaplan-Meier method applied to period-prevalent cohorts. MWTs differed markedly by blood type, donor service area, and pediatric vs adult status, but to a lesser degree by race/ethnicity. Choice of methodology affected the magnitude of these differences. Instead of waiting years for an answer, reliable kidney MWT estimates can be obtained shortly after a policy is implemented using the period-prevalent Kaplan-Meier approach, a theoretical but useful construct for which we found no evidence of bias compared with using incident cohorts. We recommend this method be used complementary to the competing risks approach, under which MWT is often inestimable, to fill the present information void concerning the seemingly simple question of how long it takes to get a kidney transplant in the United States.

Elderly Patients and Management in Intensive Care Units (ICU): Clinical Challenges

There is a growing population of older adults requiring admission to the intensive care unit (ICU). This population outpaces the ability of clinicians with geriatric training to assist in their management. Specific training and education for intensivists in the care of older patients is valuable to help understand and inform clinical care, as physiologic changes of aging affect each organ system. This review highlights some of these aging processes and discusses clinical implications in the vulnerable older population. Other considerations when caring for these older patients in the ICU include functional outcomes and morbidity, as opposed to merely a focus on mortality. An overall holistic approach incorporating physiology of aging, applying current evidence, and including the patient and their family in care should be used when caring for older adults in the ICU.

Prevalence and incidence of chronic kidney disease stage 3-5 - results from KidDiCo

BACKGROUND

Chronic kidney disease (CKD) is a global challenge. CKD prevalence estimation is central to management strategies and prevention. It is necessary to predict end stage kidney disease (ESKD) and, subsequently, the burden for healthcare systems. In this study we characterize CKD stage 3-5 prevalence and incidence in a cohort covering the majority of the Region of Southern Denmark and investigate individuals' demographic, socioeconomic, and comorbidity status.

METHODS

We used data from the Kidney Disease Cohort (KidDiCo) combining laboratory data from Southern Denmark with Danish national databases. Chronic kidney disease was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

RESULTS

The prevalence varied between 4.83 and 4.98% and incidence rate of CKD was 0.49%/year. The median age was 76.4 years. The proportion of individuals with CKD stage 3-5 in the entire population increased consistently with age. The percentage of women in the CKD 3-5 group was higher than in the background population. Diabetes mellitus, hypertension and cardiovascular disease were more prominent in patients with CKD. CKD stage 5 and ESKD were more frequent as incident CKD stages in the 18-49 year olds when compared to older individuals. CKD patients tended to have a lower socioeconomic status.

CONCLUSION

Chronic kidney disease stage 3-5 is common, especially in the elderly. Patients with CKD stage 3-5 are predominantly female. The KidDiCo data suggests an association between lower socioeconomic status and prevalence of CKD.

Hedgehog interacting protein activates sodium-glucose cotransporter 2 expression and promotes renal tubular epithelial cell senescence in a mouse model of type 1 diabetes

AIMS/HYPOTHESIS

Senescent renal tubular cells may be linked to diabetic kidney disease (DKD)-related tubulopathy. We studied mice with or without diabetes in which hedgehog interacting protein (HHIP) was present or specifically knocked out in renal tubules (Hhip^RT-KO), hypothesising that local deficiency of HHIP in the renal tubules would attenuate tubular cell senescence, thereby preventing DKD tubulopathy.

METHODS

Low-dose streptozotocin was employed to induce diabetes in both Hhip^RT-KO and control (Hhip^fl/fl) mice. Transgenic mice overexpressing Hhip in renal proximal tubular cells (RPTC) (Hhip^RPTC-Tg) were used for validation, and primary RPTCs and human RPTCs (HK2) were used for in vitro studies. Kidney morphology/function, tubular senescence and the relevant molecular measurements were assessed.

RESULTS

Compared with Hhip^fl/fl mice with diabetes, Hhip^RT-KO mice with diabetes displayed lower blood glucose levels, normalised GFR, ameliorated urinary albumin/creatinine ratio and less severe DKD, including tubulopathy. Sodium-glucose cotransporter 2 (SGLT2) expression was attenuated in RPTCs of Hhip^RT-KO mice with diabetes compared with Hhip^fl/fl mice with diabetes. In parallel, an increased tubular senescence-associated secretory phenotype involving release of inflammatory cytokines (IL-1β, IL-6 and monocyte chemoattractant protein-1) and activation of senescence markers (p16, p21, p53) in Hhip^fl/fl mice with diabetes was attenuated in Hhip^RT-KO mice with diabetes. In contrast, Hhip^RPTC-Tg mice had increased tubular senescence, which was inhibited by canagliflozin in primary RPTCs. In HK2 cells, HHIP overexpression or recombinant HHIP increased SGLT2 protein expression and promoted cellular senescence by targeting both ataxia-telangiectasia mutated and ataxia-telangiectasia and Rad3-related-mediated cell arrest.

CONCLUSIONS/INTERPRETATION

Tubular HHIP deficiency prevented DKD-related tubulopathy, possibly via the inhibition of SGLT2 expression and cellular senescence.

Utility of ultrasonography for predicting indications for tolvaptan in patients with autosomal dominant polycystic kidney disease

PURPOSE

Tolvaptan is the first approved treatment for autosomal dominant polycystic kidney disease (ADPKD) that targets a mechanism directly contributing to the development and growth of renal cysts. We investigated the ability of ultrasonography to predict total kidney volume (TKV) of 750 mL or more, which is an indication for tolvaptan therapy in patients with ADPKD.

METHODS

A total of 46 patients with ADPKD were evaluated. The most statistically appropriate measurement based on ultrasonography for predicting TKV determined by computed tomography (CT) was assessed.

RESULTS

TKV determined by CT was 796.8 (508.8-1,560.3) mL. The median length, anteroposterior distance, and mediolateral distance determined using ultrasonography were 15.7 cm, 7.6 cm, and 7.6 cm in the left kidney, and 13.4 cm, 6.9 cm, and 7.2 cm in the right kidney, respectively. Multivariate regression analysis showed that total kidney length (left and right) [variance inflation factor (VIF), 9.349] and total mediolateral distance (left and right) (VIF, 3.988) were independently associated with TKV. The correlation (r) between the logarithm of TKV determined by CT and total mediolateral distance determined using ultrasonography was 0.915 (p < 0.001). The linear regression equation was log (total kidney volume) = 1.833 + 0.075 × total mediolateral distance (left and right) based on ultrasonography. The area under the receiver operating characteristic curve for total mediolateral distance determined using ultrasonography to predict TKV of 750 mL or more was 0.989. Using the total mediolateral distance cut-off value of 14.2 cm, the sensitivity and specificity were 96.0% and 100.0%, respectively.

CONCLUSION

Total mediolateral distance determined using ultrasonography can predict TKV in patients with ADPKD.

Prostate Cancer in Renal Transplant Recipients: Results from a Large Contemporary Cohort

Objectives: The aim of this study was to assess the natural history of prostate cancer (PCa) in renal transplant recipients (RTRs) and to clarify the controversy over whether RTRs have a higher risk of PCa and poorer outcomes than non-RTRs, due to factors such as immunosuppression. Patients and Methods: We performed a retrospective multicenter study of RTRs diagnosed with cM0 PCa between 2001 and 2019. Primary outcomes were overall (OS) and cancer-specific survival (CSS). Secondary outcomes included biochemical recurrence and/or progression after active surveillance (AS) and evaluation of variables possibly influencing PCa aggressiveness and outcomes. Management modalities included surgery, radiation, cryotherapy, HIFU, AS, and watchful waiting. Results: We included 166 men from nine institutions. Median age and eGFR at diagnosis were 67 (IQR 60−73) and 45.9 mL/min (IQR 31.5−63.4). ASA score was >2 in 58.4% of cases. Median time from transplant to PCa diagnosis was 117 months (IQR 48−191.5), and median PSA at diagnosis was 6.5 ng/mL (IQR 5.02−10). The biopsy Gleason score was ≥8 in 12.8%; 11.6% and 6.1% patients had suspicion of ≥cT3 > cT2 and cN+ disease. The most frequent management method was radical prostatectomy (65.6%), followed by radiation therapy (16.9%) and AS (10.2%). At a median follow-up of 60.5 months (IQR 31−106) 22.9% of men (n = 38) died, with only n = 4 (2.4%) deaths due to PCa. Local and systemic progression rates were 4.2% and 3.0%. On univariable analysis, no major influence of immunosuppression type was noted, with the exception of a protective effect of antiproliferative agents (HR 0.39, 95% CI 0.16−0.97, p = 0.04) associated with a decreased risk of biochemical recurrence (BCR) or progression after AS. Conclusion: PCa diagnosed in RTRs is mainly of low to intermediate risk and organ-confined at diagnosis, with good cancer control and low PCa death at intermediate follow-up. RTRs have a non-negligible risk of death from causes other than PCa. Aggressive upfront management of the majority of RTRs with PCa may, therefore, be avoided.

Optimal Frequency of Urinary Albumin Screening in Type 1 Diabetes

OBJECTIVE

Kidney disease screening recommendations include annual urine testing for albuminuria after 5 years' duration of type 1 diabetes. We aimed to determine a simple, risk factor-based screening schedule that optimizes early detection and testing frequency.

RESEARCH DESIGN AND METHODS

Urinary albumin excretion measurements from 1,343 participants in the Diabetes Control and Complications Trial and its long-term follow-up were used to create piecewise-exponential incidence models assuming 6-month constant hazards. Likelihood of the onset of moderately or severely elevated albuminuria (confirmed albumin excretion rate AER ≥30 or ≥300 mg/24 h, respectively) and its risk factors were used to identify individualized screening schedules. Time with undetected albuminuria and number of tests were compared with annual screening.

RESULTS

The 3-year cumulative incidence of elevated albuminuria following normoalbuminuria at any time during the study was 3.2%, which was strongly associated with higher glycated hemoglobin (HbA1c) and AER. Personalized screening in 2 years for those with current AER ≤10 mg/24 h and HbA1c ≤8% (low risk [0.6% three-year cumulative incidence]), in 6 months for those with AER 21-30 mg/24 h or HbA1c ≥9% (high risk [8.9% three-year cumulative incidence]), and in 1 year for all others (average risk [2.4% three-year cumulative incidence]) was associated with 34.9% reduction in time with undetected albuminuria and 20.4% reduction in testing frequency as compared with annual screening. Stratification by categories of HbA1c or AER alone was associated with reductions of lesser magnitude.

CONCLUSIONS

A personalized alternative to annual screening in type 1 diabetes can substantially reduce both the time with undetected kidney disease and the frequency of urine testing.

ARTICLE HIGHLIGHTS

Kidney disease screening recommendations include annual urine testing for albuminuria after 5 years' duration of type 1 diabetes. We investigated simple screening schedules that optimize early detection and testing frequency. Personalized screening in 2 years for those with current AER ≤10 mg/24 h and HbA1c ≤8%, in 6 months for those with AER 21-30 mg/24 h or HbA1c ≥9%, and in 1 year for all others yielded 34.9% reduction in time with undetected albuminuria and 20.4% fewer evaluations compared with annual screening. A personalized alternative to annual screening in type 1 diabetes can substantially reduce both the time with undetected kidney disease and the frequency of urine testing.

Patient-Reported Outcome Dashboards Within the Electronic Health Record to Support Shared Decision-making: Protocol for Co-design and Clinical Evaluation With Patients With Advanced Cancer and Chronic Kidney Disease

BACKGROUND

Patient-reported outcomes-symptoms, treatment side effects, and health-related quality of life-are important to consider in chronic illness care. The increasing availability of health IT to collect patient-reported outcomes and integrate results within the electronic health record provides an unprecedented opportunity to support patients' symptom monitoring, shared decision-making, and effective use of the health care system.

OBJECTIVE

The objectives of this study are to co-design a dashboard that displays patient-reported outcomes along with other clinical data (eg, laboratory tests, medications, and appointments) within an electronic health record and conduct a longitudinal demonstration trial to evaluate whether the dashboard is associated with improved shared decision-making and disease management outcomes.

METHODS

Co-design teams comprising study investigators, patients with advanced cancer or chronic kidney disease, their care partners, and their clinicians will collaborate to develop the dashboard. Investigators will work with clinic staff to implement the co-designed dashboard for clinical testing during a demonstration trial. The primary outcome of the demonstration trial is whether the quality of shared decision-making increases from baseline to the 3-month follow-up. Secondary outcomes include longitudinal changes in satisfaction with care, self-efficacy in managing treatments and symptoms, health-related quality of life, and use of costly and potentially avoidable health care services. Implementation outcomes (ie, fidelity, appropriateness, acceptability, feasibility, reach, adoption, and sustainability) during the co-design process and demonstration trial will also be collected and summarized.

RESULTS

The dashboard co-design process was completed in May 2020, and data collection for the demonstration trial is anticipated to be completed by the end of July 2022. The results will be disseminated in at least one manuscript per study objective.

CONCLUSIONS

This protocol combines stakeholder engagement, health care coproduction frameworks, and health IT to develop a clinically feasible model of person-centered care delivery. The results will inform our current understanding of how best to integrate patient-reported outcome measures into clinical workflows to improve outcomes and reduce the burden of chronic disease on patients and health care systems.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/38461.

Accuracy, Reproducibility and User Experience With Standardized Instructions for Measurement of Total Kidney Volume in Autosomal Dominant Polycystic Kidney Disease

PURPOSE

Total kidney volume (TKV) measurement is integral in clinical management of autosomal dominant polycystic kidney disease (ADPKD) but the gold standard of measurement via stereology/manual planimetry is time-consuming and not readily available to clinicians. This study assessed whether standardized measurement instructions based on an ellipsoid equation enhanced TKV assessment on computed tomographic (CT) images of the kidneys as determined by accuracy, reproducibility, efficiency and/or user acceptability.

METHODS

Participating radiologists were randomized to perform TKV measurements with or without standardized instructions. All participants measured the same 3 non-contrast, low-dose CT scans. Accuracy was assessed as variation from TKV measurements obtained by planimetry. Intraclass correlation coefficients and time to complete the measurements were assessed. Surveys assessed prior experience with TKV measurement and user acceptability of the instructions.

RESULTS

49 radiologists participated. There was no difference in accuracy or measurement time between instructed and non-instructed participants. There was a trend towards greater reproducibility with standardized instructions (ICC .8 vs .6). 92% of respondents indicated the instructions were easy to use, 86% agreed the instructions would enhance their comfort with TKV measurement and 75% agreed they would recommend these instructions to colleagues.

CONCLUSIONS

Instructed and non-instructed participants demonstrated similar accuracy and time required for TKV measurement, but instructed participants had a trend towards greater reproducibility. There was high acceptability including enhanced user confidence with the instructions. Standardized instructions may be of value for radiologists seeking to improve their confidence in providing clinicians with TKV measurements necessary to appropriately manage this patient population.

Kidney Retransplantation after Graft Failure: Variables Influencing Long-Term Survival

Background

There is an increasing demand for kidney retransplantation. Most studies report inferior outcomes compared to primary transplantation, consequently feeding an ethical dilemma in the context of chronic organ shortage.

Objective

To assess variables influencing long-term graft survival after kidney retransplantation. Material and Methods. All patients transplanted at our center between 2000 and 2016 were analyzed retrospectively. Survival was estimated with the Kaplan–Meier method, and risk factors were identified using multiple Cox regression.

Results

We performed 1,376 primary kidney transplantations and 222 retransplantations. The rate of retransplantation was 67.8% after the first graft loss, with a comparable 10-year graft survival compared to primary transplantation (67% vs. 64%, p=0.104) but an inferior graft survival thereafter (log-rank p=0.026). Independent risk factors for graft survival in retransplantation were age ≥ 50 years, time on dialysis ≥1 year, previous graft survival <2 years, ≥1 mild comorbidity in the Charlson–Deyo index, active smoking, and life-threatening complications (Clavien–Dindo grade IV) at first transplantation.

Conclusion

Graft survival is comparable for first and second kidney transplantation within the first 10 years. Risk factors for poor outcomes after retransplantation are previous graft survival, dialysis time after graft failure, recipient age, comorbidities, and smoking. Patients with transplant failure should have access to retransplantation as early as possible.

Robotic Radical Prostatectomy for Prostate Cancer in Renal Transplant Recipients: Results from a Multicenter Series

BACKGROUND

Despite an expected increase in prostate cancer (PCa) incidence in the renal transplant recipient (RTR) population in the near future, robot-assisted radical prostatectomy (RARP) in these patients has been poorly detailed. It is not well understood whether results are comparable to RARP in the non-RTR setting.

OBJECTIVE

To describe the surgical technique for RARP in RTR and report results from our multi-institutional experience.

DESIGN, SETTING, AND PARTICIPANTS

This was a retrospective review of the experience of four referral centers.

SURGICAL PROCEDURE

Transperitoneal RARP with pelvic lymph node dissection in selected patients.

MEASUREMENTS

We measured patient, PCa, and graft baseline features; intraoperative and postoperative parameters; complications, (Clavien classification); and oncological and functional outcomes.

RESULTS AND LIMITATIONS

We included 41 men. The median age, American Society of Anesthesiologists score, preoperative renal function, and prostate-specific antigen were 60 yr (interquartile range [IQR] 57-64), 2 points (IQR 2-3), 45 ml/min (IQR 30-62), and 6.5 ng/ml (IQR 5.2-10.2), respectively. Four men (9.8%) had a biopsy Gleason score >7. The majority of the patients (70.7%) did not undergo lymphadenectomy. The median operating time, hospital stay, and catheterization time were 201 min (IQR 170-250), 4 d (IQR 2-6), and 10 d (IQR 7-13), respectively. At final pathology, 11 men had extraprostatic extension and seven had positive surgical margins. At median follow-up of 42 mo (IQR 24-65), four men had biochemical recurrence, including one case of local PCa persistence and one local recurrence. No metastases were recorded while two patients died from non-PCa-related causes. Continence was preserved in 86.1% (p not applicable) and erections in 64.7% (p = 0.0633) of those who were continent/potent before the procedure. Renal function remained unchanged (p = 0.08). No intraoperative complications and one major (Clavien 3a) complication were recorded.

CONCLUSIONS

RARP in RTR is safe and feasible. Overall, operative, oncological, and functional outcomes are comparable to those described for the non-RTR setting, with graft injury remaining undescribed. Further research is needed to confirm our findings.

PATIENT SUMMARY

Robot-assisted removal of the prostate is safe and feasible in patients who have a kidney transplant. Cancer control, urinary and sexual function results, and surgical complications seem to be similar to those for patients without a transplant, but further research is needed.

Use of Guideline-Based Therapy for Diabetes, Coronary Artery Disease, and Chronic Kidney Disease After Acute Kidney Injury: A Retrospective Observational Study

Background

Survivors of acute kidney injury (AKI) are at a high risk for cardiovascular complications. An underrecognition of this risk may contribute to the low utilization of relevant guideline-based therapies in this population.

Objective

We sought to assess accordance with guideline-based recommendations for survivors of AKI with diabetes, coronary artery disease (CAD), and preexisting chronic kidney disease (CKD) in a post-AKI clinic, and identify factors that may be associated with guideline accordance.

Design

Retrospective cohort study.

Setting

Post-AKI clinics at 2 tertiary care centers in Ontario, Canada.

Patients

We included adult patients seen in both post-AKI clinics between 2013 and 2019 who had at least 2 clinic visits within 24 months of an index AKI hospitalization.

Measurements

We assessed accordance to recommendations from the most recent North American and international guidelines available at the time of study completion for diabetes, CAD, and CKD.

Methods

We compared guideline accordance between visits using the Cochran Mantel Haenszel test. We used multivariable Poisson regression to identify prespecified factors associated with accordance.

Results

Of 213 eligible patients, 192 (90%) had Kidney Disease Improving Global Outcomes Stage 2-3 AKI, 91 (43%) had diabetes, 76 (36%) had CAD, and 88 (41%) had preexisting CKD. From the first clinic visit to the second, there was an increase in angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACE-I/ARB) use across all disease groups-from 33% to 46% (P = .028) in patients with diabetes, from 30% to 57% (P = .002) in patients with CAD, and from 16% to 35% (P < .001) in patients with preexisting CKD. Statin use increased in patients with preexisting CKD from 64% to 71% (P = .034). Every 25 μmol/L rise in the discharge serum creatinine was associated with a 19% (95% confidence interval [CI], 8%-28%) and 12% (95% CI, 2%-21%) lower likelihood of being on an ACE-I/ARB in patients with diabetes and preexisting CKD, respectively.

Limitations

The study lacked a comparison group that received usual care. The small sample and multiple comparisons make false positives possible.

Conclusion

There is room to improve guideline-based cardiovascular risk factor management in survivors of AKI, particularly ACE-I/ARB use in patients with an elevated discharge serum creatinine.

Association of Uric Acid-Lowering Therapy With Incident Chronic Kidney Disease

IMPORTANCE

Uric acid is a waste metabolite produced from the breakdown of purines, and elevated serum uric acid levels are associated with higher risk of hypertension, cardiovascular disease, and mortality and progression of chronic kidney disease (CKD). Treatment of hyperuricemia in patients with preexisting CKD has not been shown to improve kidney outcomes, but the associations of uric acid-lowering therapies with the development of new-onset kidney disease in patients with estimated glomerular filtration rate (eGFR) within reference range and no albuminuria is unclear.

OBJECTIVE

To examine the association of initiating uric acid-lowering therapy with the incidence of CKD.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included patients with eGFR of 60 mL/min/1.73 m2 or greater and no albuminuria treated at US Department of Veterans Affairs health care facilities from 2004 to 2019. Clinical trial emulation methods, including propensity score weighting, were used to minimize confounding. Data were analyzed from 2020 to 2022.

EXPOSURE

Newly started uric acid-lowering therapy.

MAIN OUTCOMES AND MEASURES

The main outcomes were incidences of eGFR less than 60 mL/min/1.73 m2, new-onset albuminuria, and end-stage kidney disease.

RESULTS

A total of 269 651 patients were assessed (mean [SD] age, 57.4 [12.5] years; 252 171 [94%] men). Among these, 29 501 patients (10.9%) started uric acid-lowering therapy, and 240 150 patients (89.1%) did not. Baseline characteristics, including serum uric acid level, were similar among treated and untreated patients after propensity score weighting. In the overall cohort, uric acid-lowering therapy was associated with higher risk of both incident eGFR less than 60 mL/min/1.73 m2 (weighted subhazard ratio [SHR], 1.15 [95% CI, 1.10-1.20; P < .001) and incident albuminuria (SHR, 1.05 [95% CI, 1.01-1.09; P < .001) but was not associated with the risk of end-stage kidney disease (SHR, 0.96 [95% CI, 0.62-1.50]; P = .87). In subgroup analyses, the association of uric acid-lowering therapy with worse kidney outcomes was limited to patients with baseline serum uric acid levels of 8 mg/dL or less.

CONCLUSIONS AND RELEVANCE

These findings suggest that in patients with kidney function within reference range, uric acid-lowering therapy was not associated with beneficial kidney outcomes and may be associated with potential harm in patients with less severely elevated serum uric acid levels.