Hyperkalemia Incidence in Patients With Non-Dialysis Chronic Kidney Disease: A Large Retrospective Cohort Study From United States Clinical Care.

Rationale & Objective: Estimates of the incidence of hyperkalemia in patients with chronic kidney disease (CKD) vary widely. Our objective was to estimate hyperkalemia incidence in patients with CKD from routine clinical care, including by level of kidney damage or function and among important patient subgroups. Study Design: Retrospective cohort study. Setting & Participants: 1,771,900 patients with stage 1-4 CKD identified from the US Optum De-Identified electronic health records database. Exposures or Predictors: Impaired kidney damage or function level at baseline based on urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR), respectively, and selected patient subgroups. Outcomes: Hyperkalemia: 2 elevated serum potassium values (≥5.5 mmol/L) from the inpatient setting (2-24 hours apart) or outpatient setting (maximum 7 days apart), or 1 elevated serum potassium value plus pharmacotherapy initiation or hyperkalemia diagnosis (maximum 3 days apart). Analytical Approach: Incidence rates of hyperkalemia were calculated. Estimates were stratified by UACR and eGFR level at baseline and patient subgroups. Results: Over a mean follow-up of 3.9 years, the incidence of hyperkalemia was 3.37 events/100 person-years (95% confidence intervals, 3.36-3.38). Higher incidence rates were observed with increased UACR and lower eGFR. Highest rates were observed with UACR ≥3,500 (up to 19.1/100 person-years) irrespective of decreased eGFR level. High rates also occurred in patients with type 2 diabetes mellitus (T2DM, 5.43/100 person-years), heart failure (8.7/100 person-years), and those prescribed steroidal mineralocorticoid receptor antagonists (sMRAs, 7.7/100 person-years). Limitations: Potential misclassification of variables from possible medical coding errors; potential data incompleteness issues if patients received care at institutions not included in Optum. Conclusions: Hyperkalemia is a frequent occurrence in CKD, particularly in patients with T2DM, heart failure, or prescribed sMRAs, indicating the need for regular serum potassium and UACR monitoring in this patient population to help mitigate risk.

People with chronic kidney disease (CKD) have a higher risk of illness, hospitalization, and death than those without CKD. Medicines that are commonly used to slow down CKD progression can sometimes lead to hyperkalemia, where levels of potassium in the blood are higher than normal and which can be potentially dangerous. Concerns about hyperkalemia have led some people with CKD to stop taking their medication. Our study of 1.7 million patients from the United States found that patients with severe kidney damage, as well as those with type 2 diabetes mellitus or heart failure, have a higher risk of hyperkalemia than other patients, indicating they are priority groups for having their potassium levels and level of kidney damage checked regularly.

Prevalence and associated factors of glomerular hyperfiltration among adult stable sickle cells in Kinshasa, DR Congo.

INTRODUCTION: Glomerular hyperfiltration is highly frequent, theoretically dependent on cardiac output, low systemic vascular resistance and hemolysis markers. In sickle cell disease (SCD), hyperfiltration is an extremely common phenomenon and occurred in young and early adult patients. Despite the fact that the glomerular hyperfiltration is known as the early manifestations of sickle cell nephropathy, its burden among adult sickle cell disease in sub-Saharan is poor studied. This study aimed to determine the prevalence and associated factors of hyperfiltration. METHODS: This was an analytical multicentric cross-sectional study involving stable adult sickle cell patients in Kinshasa, recruited between March and October 2023. Parameters of interest encompasses demographic, clinical, biological, echocardiographic and pulse wave measurement data. Hyperfiltration was defined using the CDK-EPI equation based on cystatin C; eGFR >130 for women and >140 ml/min/1.73m2 for men. We used multivariate logistic regression analysis to search determinants of glomerular hyperfiltration. RESULTS: Two hundred and fourty six (246) patients with SCD were enrolled. The prevalence of hyperfiltration was 20.7%. In multiple logistic regression analysis, hyperfiltration status was independently associated with age (< 25 years) [3.57 (1.78-7.49); p = 0.027)], female sex [4.36 (2.55-5.62); p = 0.031), CRP (< 6 mg/l) [0.77 (0.61-0.97); p = 0.028)], central systolic pressure (< 100 mmHg) and central diastolic pressure (< 60 mmHg) [0.86(0.74-0.98), p = 0.028)], [(0.83 (0.71-0.98); p = 0.032)]. CONCLUSION: One out of five SS adults exhibits hyperfiltration, which is associated with young age and female sex, whereas low CRP and blood pressure were negative risk factors.

"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 %.

Risk factors for lower renal compensation after nephrectomy: an analysis of living kidney donors in an Amazonian cohort / Fatores de risco para menor compensação renal pós-nefrectomia: análise de doadores de rim vivo em uma coorte amazônica

Abstract Introduction: Living donor kidney transplantation is considered the ideal renal replacement therapy because it has a lower complication rate and allows an efficient response to the high demand for grafts in the healthcare system. Careful selection and adequate monitoring of donors is a key element in transplantation. Individuals at greater risk of developing kidney dysfunction after nephrectomy must be identified. Objective: To identify risk factors associated with a renal compensation rate (CR) below 70% 12 months after nephrectomy. Methods: This observational retrospective longitudinal study included living kidney donors followed up at the Lower Amazon Regional Hospital between 2016 and 2022. Data related to sociodemographic variables, comorbid conditions and kidney function parameters were collected. Results: The study enrolled 32 patients. Fourteen (43.75%) had a CR < 70% 12 months after kidney donation. Logistic regression found obesity (Odds Ratio [95%CI]: 10.6 [1.7-65.2]), albuminuria (Odds Ratio [95%CI]: 2.41 [1.2-4.84]) and proteinuria (Odds Ratio [95%CI]: 1.14 [1.03-1.25]) as risk factors. Glomerular filtration rate was a protective factor (Odds Ratio [95% CI]: 0.92 [0.85-0.99]). Conclusion: Obesity, albuminuria and proteinuria adversely affected short-term renal compensation rate. Further studies are needed to uncover the prognostic implications tied to these risk factors. Our findings also supported the need for careful individualized assessment of potential donors and closer monitoring of individuals at higher risk.

Resumo Introdução: O transplante de rim de doador vivo é considerado a terapia renal substitutiva ideal por oferecer menor taxa de complicações e possibilitar uma resposta eficiente à grande demanda por enxertos no sistema de saúde. A seleção criteriosa e o acompanhamento adequado dos doadores constituem um pilar fundamental dessa modalidade terapêutica, sendo essencial a identificação dos indivíduos em maior risco de disfunção renal pós-nefrectomia. Objetivo: Identificar fatores de risco para uma Taxa de Compensação (TC) da função renal inferior a 70% 12 meses após a nefrectomia. Métodos: Estudo observacional, retrospectivo e longitudinal conduzido com doadores de rim vivo acompanhados no Hospital Regional do Baixo Amazonas entre 2016 e 2022. Foram coletados dados correspondentes a variáveis sociodemográficas, comorbidades e parâmetros de função renal. Resultados: Foram incluídos 32 pacientes na amostra final. Destes, 14 (43,75%) obtiveram TC < 70% 12 meses após a doação. A regressão logística identificou a obesidade (Odds Ratio [IC95%]: 10.6 [1.7-65.2]), albuminúria (Odds Ratio [IC95%]: 2.41 [1.2-4.84]) e proteinúria (Odds Ratio [IC95%]: 1.14 [1.03-1.25]) como fatores de risco. A taxa de filtração glomerular atuou como fator de proteção (Odds Ratio [IC95%]: 0.92 [0.85-0.99]). Conclusão: Obesidade, albuminúria e proteinúria demonstraram impacto negativo na taxa de compensação renal em curto prazo, o que reitera a necessidade de estudos acerca das implicações prognósticas desses fatores. Além disso, reforça-se a necessidade de avaliação cuidadosa e individualizada dos possíveis doadores, com acompanhamento rigoroso, especialmente para indivíduos de maior risco.

Lessons learned from the FinnDiane Study: Epidemiology and metabolic risk factors for diabetic kidney disease in type 1 diabetes.

AIMS: Across its operational span of more than 25 years, the observational, nationwide, multicentre Finnish Diabetic Nephropathy (FinnDiane) Study has aimed to unravel mechanisms underlying diabetic kidney disease, with a special focus on its metabolic risk factors. We sought to compile key findings relating to this topic and to offer a current perspective on the natural course of diabetic kidney disease among individuals with type 1 diabetes. METHODS: In this narrative review, articles relevant to the subject published by the FinnDiane Study were identified and summarized together with work published by others, when relevant. RESULTS: The FinnDiane Study has underscored the significance of dysglycaemia and insulin resistance, increased visceral fat mass, hypertension and dyslipidaemia-particularly high triglycerides and remnant cholesterol-as risk factors for diabetic kidney disease. Factors like abdominal obesity seem to influence the early stages of the disease, while the presence of the metabolic syndrome becomes implicated at later stages. Epidemiological reports have revealed that after an initial decline, the cumulative incidence of albuminuria plateaued post-1980s, with the progression rate to kidney failure remaining high. Fortunately, 23% of the FinnDiane cohort regressed to less advanced stages of albuminuria, improving their overall prognosis. CONCLUSION: A substantial burden of albuminuria associated with type 1 diabetes persists, and therefore, novel kidney-protecting therapies are highly awaited. In addition, given that metabolic factors influence the progression of diabetic kidney disease both in its early and advanced stages, emphasis should be placed on ensuring that their treatment targets are met.

Association between the lipid accumulation product and chronic kidney disease among adults in the United States.

The objective of this research was to explore the potential association between lipid accumulation product (LAP) and chronic kidney disease (CKD) among adult population of United States (US). Using cross-sectional data from the 2013 to 2018 National Health and Nutrition Examination Survey (NHANES), we explored the association of LAP with CKD, low estimated glomerular filtration rate (eGFR), and albuminuria. This analysis encompassed multivariate logistic regression analyses, smoothed curve fitting, subgroup analyses, and interaction tests. We found a significant positive association between higher ln-transformed LAP (LAP was transformed using a natural logarithm) and the prevalence of CKD, low-eGFR and albuminuria. Notably, this association of ln-transformed LAP with CKD and albuminuria was significantly influenced by diabetes status and sex (P for interaction < 0.05), while no significant interaction was observed regarding the association with low-eGFR (P for interaction > 0.05). Additionally, in model 3 (adjusted for all included covariates except eGFR and urinary albumin-creatinine ratio (UACR)), a nonlinear relationship was identified between ln-transformed LAP and the presence of both CKD and albuminuria, with inflection points of 4.57 and 4.49, respectively. This indicates that this correlation is more pronounced on the right of the inflection point. In conclusion, the findings indicate a significant association between LAP and the prevalence of CKD in US adults.

Impact of Dapagliflozin Adjunctive Therapy on the Progression of Chronic Kidney Disease in Patients with Type 2 Diabetes and Chronic Kidney Disease Stages 2-5: A systematic review and meta-analysis.

This meta-analysis investigated efficacy of dapagliflozin as adjunctive therapy for patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) stages 2-5. A systematic search was conducted of selected databases for randomised controlled trials that reported the mean change in estimated glomerular filtration rate (eGFR) and urine albumin-creatinine ratio (UACR) from baseline. Out of 1,682 identified studies, 9 trials comprising 13,057 patients were included. A pooled estimate of 5 studies indicated that dapagliflozin did not affect eGFR; however, in 2 studies, it significantly reduced chronic eGFR decline compared to placebo (mean difference [MD] ± 2.74; 95% confidence interval [CI]: 1.55, 3.92; P <0.00001). Additionally, a pooled estimate of 4 studies showed that dapagliflozin significantly reduced UACR (MD -23.99%; 95% CI: -34.82--13.15; P <0.0001; I2 = 0%). Therefore, long-term use of dapagliflozin significantly attenuates eGFR decline and reduces albuminuria in patients with T2DM and CKD.

U-shaped association between hemoglobin levels and albuminuria in US adults: a cross-sectional study.

PURPOSE: This study aimed to explore the correlation between hemoglobin levels and albuminuria in US adults. METHODS: This cross-sectional investigation analyzed the National Health and Nutrition Examination Survey (NHANES) information from 2011 to 2020. Data on hemoglobin, albuminuria, and other variables were collected from all participants. The logistic-regression analyses and smoothed curves were used to substantiate the research objectives. RESULTS: The average age of the 8,868 participants was 49.5 ± 17.3 years, and 49.3% were men. The prevalence of albuminuria was 12.1%. After adjusting for potential variables in the logistic-regression analysis models, hemoglobin (per 1 g/dL increase) was inversely associated with the presence of albuminuria (odds ratio [OR], 0.92; 95% confidence interval [95%CI], 0.87-0.97). Compared with participants in quartile 3 (Q3, 14.1-15.0 g/dL) for hemoglobin levels, those in the lowest quartile 1 (Q1, 6.1-13.0 g/dL) and highest quartile 4 (Q4, 15.1-19.6 g/dL) had adjusted ORs for albuminuria of 1.48 (95% CI, 1.19-1.85) and 1.11 (95% CI, 0.9-1.38), respectively. Our observations indicated a U-shaped association between hemoglobin levels and albuminuria, with a point of inflection at approximately 15.5 g/dL. The effect sizes and CIs below and above this point were 0.853 (95% CI, 0.798-0.912) and 1.377 (95% CI, 1.055-1.797), respectively. CONCLUSION: This study indicates that the presence of albuminuria is linked to both low and high hemoglobin levels in US adults. The management of hemoglobin may benefit kidney health.

Association of biomarkers of endothelial function, coagulation activation and kidney injury with persistent albuminuria in sickle cell anaemia.

Persistent albuminuria (PA) is common in sickle cell anaemia (SCA). With the association of chronic kidney disease (CKD) with increased mortality, biomarkers that predict its development or progression are needed. We evaluated the association of select biomarkers with PA in adults with SCA using Kruskal-Wallis rank-sum test and logistic regression models, with adjustment for multiple testing. Of 280 subjects, 100 (35.7%) had PA. Median plasma levels of soluble vascular cell adhesion molecule-1 (VCAM-1) (1176.3 vs. 953.4 ng/mL, false discovery rate [FDR] q-value <0.003), thrombin-antithrombin complex (5.5 vs. 4.7 ng/mL, FDR q-value = 0.04), and urinary angiotensinogen (AGT) (12.2 vs. 5.3 ng/mg, FDR q-value <0.003), urinary nephrin (30.6 vs. 27.2 ng/mg, FDR q-value = 0.04), and urinary kidney injury molecule-1 (KIM-1) (0.8 vs. 0.5 ng/mg, FDR q-value <0.003), normalized to urine creatinine, were significantly higher in subjects with PA. In multivariable analysis, only urinary AGT (odds ratio = 1.058, FDR q-value <0.0001) remained a significant predictor of PA. In addition, soluble VCAM-1 (FDR q-value <0.0001), D-dimer (FDR q-value <0.0001), urinary AGT (FDR q-value <0.0001), KIM-1 (FDR q-value <0.0001), and nephrin (FDR q-value <0.0001) were significantly associated with urine albumin-creatinine ratio in multivariable analyses. Longitudinal studies to evaluate the predictive capacity of biomarkers for the development and progression of CKD in SCA are warranted.

Effectiveness and safety of finerenone in diabetic kidney disease patients: a real-world observational study from China.

AIMS: Finerenone has been approved for treating diabetic kidney disease (DKD) with reducing cardiorenal risk. Real-world data on finerenone treatment for the management of DKD are presently lacking. This study aimed to investigate the effect of finerenone on the renal parameters of the Chinese DKD population in the real-world medical setting for the first time, especially in combination with renin-angiotensin system inhibitors (RASi) and sodium-glucose cotransporter 2 inhibitors (SGLT2i). METHODS: Forty-two DKD patients were selected and completed a 6-month finerenone treatment. Renal parameters and adverse effects were collected at every visit. RESULTS: The median urine albumin-to-creatinine ratio (UACR) was 1426.11 (755.42, 3638.23) mg/g. Among them, the proportion of patients with a UACR of 300-5000 mg/g was 76.2%, and the proportion of patients with a UACR of >5000 mg/g was 14.3%. The median estimated glomerular filtration rate (eGFR) was 54.50 (34.16, 81.73) mL/min/1.73 m2. Finerenone decreased the UACR significantly throughout the study period (p < .05). The maximal decline of UACR at month 6 was 73%. Moreover, the proportion of patients with a 30% or greater reduction in UACR was 68.42% in month 6. There was a smaller decline (9-11%) in the eGFR after initiating finerenone (p > .05). One patient each discontinued finerenone due to hyperkalemia (2.4%) and acute kidney injury (2.4%). No patient reported hypotension, breast pain, and gynecomastia. CONCLUSIONS: This study from China first demonstrated finerenone decreased UACR with manageable safety in real-world DKD treatment. A triple regimen of RASi, SGLT2i, and finerenone may be a promising treatment strategy for lowering albuminuria and reducing hyperkalemia risk in advanced DKD patients.

Glucagon receptor activation contributes to the development of kidney injury.

The underlying causes of diabetic kidney disease are still largely unknown. New insights into the contributing causes of diabetic nephropathy are important in order to prevent this complication. Hyperglycemia and hypertension are some of the risk factors for diabetic nephropathy. However, the incidence of diabetic nephropathy is increasing despite efforts to normalize blood-glucose levels and blood pressure. Therefore, other factors should be investigated as causes of diabetic nephropathy. We investigated whether long-term increased plasma levels of glucagon contribute to the development of pathophysiological changes in kidney function as seen in patients with diabetic nephropathy. Using mouse models of chronic activation and inactivation of glucagon receptor signaling, we investigated whether glucagon is involved in changes in renal function, renal structural and transcriptional changes. We found several histopathological changes in the kidney, such as thickening of the parietal layer of Bowman's capsule, glomerular mesangial cell expansion, and significant albuminuria in the mice with activated glucagon receptor signaling. Opposite effects on mesangial area expansion and the development of albuminuria were demonstrated in mice with glucagon receptor inactivation. RNA sequencing data revealed that transcription of genes related to fatty acid metabolism, podocytes, Na+/K+-ATPase, and sodium/glucose transport were significantly changed in mice with activated glucagon receptor signaling. These data implicate that the glucagon receptor signaling is involved in the development of kidney injury, as seen in type 2 diabetes and that glucagon receptor is a potential therapeutic target in the treatment of diabetes.

Urine Protein to Creatinine Ratio for the Assessment of Bevacizumab-Associated Proteinuria in Patients with Gynecologic Cancers: A Diagnostic and Quality Improvement Study.

Proteinuria is a common adverse event arising from treatment with bevacizumab, requiring diagnostic testing via 24-h urine collection. However, this method is cumbersome. We assessed urine screenings in gynecologic cancer patients from February 2021 to May 2022. Along with a simple urine dipstick (UD), the urine microalbumin, total protein, and creatinine were measured and calculated as the urine albumin to creatinine ratio (UACR) and the urine protein to creatinine ratio (UPCR), which were further adjusted through the Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration equations to be estimated and correlated with 24-h urine total protein content. The incremental cost-effectiveness ratio was used for cost analysis. There were 129 urine samples from 36 patients. The sensitivity and specificity for the UACR were 0.56 and 0.97, and for the UPCR, 0.71 and 0.88, respectively. The 24-h TP correlated strongly with the UACR (r = 0.75; p < 0.001) and UPCR (r = 0.79; p < 0.001) and fair for the simple UD (r = 0.35; p < 0.001). The UPCR saves one unnecessary 24-h urine test for less than a dollar compared to a simple UD. The results indicate that using the UPCR could enhance diagnostic accuracy, lower costs, and reduce unnecessary 24-h urine sampling.

Proteinuria Assessment and Therapeutic Implementation in Chronic Kidney Disease Patients-A Clinical Audit on KDIGO ("Kidney Disease: Improving Global Outcomes") Guidelines.

Background/Objectives: Chronic kidney disease (CKD) is a major health problem with a rising prevalence due to comorbidities like diabetes and hypertension. The aim of this research was to audit the assessment and therapeutic management of proteinuria in CKD patients at the Cantonal Hospital Baselland (KSBL) in Switzerland and determine associations between patient comorbidities, rehospitalisation, death, and the quality of therapeutic management. Methods: We analysed data from 427 adults with CKD (eGFR < 45 mL/min/1.73 m2) hospitalised on the internal medicine ward in 2022. Results: The mean age was 85 years (range: 79-89), 45.9% were female, and the median eGFR was 32.8 mL/min/1.73 m2 (range: 25-40). Proteinuria assessment was performed in 120 (28.1%) patients (the ProtU group), and a corresponding treatment was prescribed in 59%. The ProtU group had a higher quota of patients with diabetes (44.1% vs. 33%, p = 0.048) and obesity (21.2% vs. 12.5%, p = 0.039) when compared to the group without proteinuria assessment (the Ustix group). Twelve-month survival was not significantly different between the groups (HR: 0.75; 95% CI: 0.488-1.154; p-value = 0.191). However, survival was significantly better in patients who received an antiproteinuric treatment compared to those who did not (HR: 0.30; 95% CI: 0.121-0.0761; p = 0.011). Conclusions: Improvements need to be made in managing CKD at the KSBL in accordance with the guidelines.

Summary of Research: Dapagliflozin Utilization in Chronic Kidney Disease and Its Real-World Effectiveness Among Patients with Lower Levels of Albuminuria in the USA and Japan.

This is a summary of the original article 'Dapagliflozin Utilization in Chronic Kidney Disease and Its Real-World Effectiveness Among Patients with Lower Levels of Albuminuria in the USA and Japan'. The slowing down of kidney function decline is important for managing chronic kidney disease (CKD) and preventing its complications. Clinical trials of dapagliflozin, a sodium-glucose cotransporter-2 inhibitor (SGLT-2i), have shown reductions in disease progression and death in patients with CKD and elevated levels of albuminuria. This summary of research provides an overview of a previously published article that aimed to find out whether dapagliflozin is also effective in patients with lower levels of albuminuria [urinary albumin-to-creatinine ratio (UACR) below 200 mg/g]. Starting dapagliflozin was associated with slower kidney function decline in patients with CKD and UACR below 200 mg/g compared with not starting. This effect was also observed in a subgroup analysis of patients without type 2 diabetes. These results suggest that the established benefits of SGLT-2is may extend to patients with lower levels of albuminuria.

Inter-laboratory variation for urine albumin among laboratories in a Swedish external quality assessment scheme 2005-2023.

INTRODUCTION: Increased albuminuria is associated with elevated mortality. Urine albumin (U-ALB) above 20 mg/L or albumin-to-creatinine ratio (U-ACR) of 3 g/mol are indicative of moderately increased albuminuria. Due to limited standardization among U-ALB methods, diagnosis of increased albuminuria might prove difficult. MATERIALS AND METHODS: Data from Equalis's external quality assessment scheme for low U-ALB levels during 2005-2023 were categorized according to manufacturer and divided into central laboratory (CLAB) and point-of-care testing (POCT) methods. Manufacturer median values were compared to total group mean consensus values and manufacturer CV% was compared at different U-ALB levels. RESULTS: CLAB was generally closer to consensus values and had lower CV% than POCT at U-ALB levels around 20 mg/L. For CLAB, Roche methods were approximately equal to consensus U-ALB, Abbott 4 % above, and Siemens 5 % below. For POCT, HemoCue was 1 % below, Siemens 7 % above, and Abbott 8 % below. For U-Creatinine, all manufacturers generally had a good agreement differing on average by 1-4 % from consensus. CONCLUSIONS: Although U-ALB methods generally meet The National Kidney Disease Education Program (NKDEP) recommendations of method bias less than 13 % and imprecision less than 30 %, differences among manufacturers have increased over the last years, with 2023 showing the largest differences between methods. This highlights the need for guidelines for albuminuria and ACR to take method differences into consideration, but also for implementation of suitable urine reference materials.

Urinary extracellular vesicles as a monitoring tool for renal damage in patients not meeting criteria for chronic kidney disease.

Background: Current definition of chronic kidney disease (CKD) identifies only advanced stages, but effective management demands early detection. Urinary albumin-to-creatinine ratio (ACR) 30 mg/g is a cut-off point for CKD clinical diagnosis. Patients with lower values (normoalbuminuria) and eGFR > 60 mL/min/1.73 m2 are considered at no increased cardiorenal risk. However, higher incidence of renal function decline and cardiovascular events have been shown within the normoalbuminuria range. Novel subclinical indicators may help to identify higher-risk patients. Urinary extracellular vesicles (uEVs) are sentinels of renal function non-invasively. Here we aimed to approach the early assessment of cardiorenal risk by investigating the protein cargo of uEVs. Methods: Hypertensive patients were classified in control group (C) with ACR < 10 mg/g, and high-normal group (HN) with ACR 10-30 mg/g. Isolated uEVs were characterized by western blotting and electron microscopy and the protein cargo was analyzed by untargeted proteomics (LC-MS/MS) in a first discovery cohort. Protein confirmation was performed in a different cohort by ExoView. Immunohistochemistry of human kidney biopsies was also performed to evaluate the potential of uEVs to reflect renal damage. Results: HN albuminuria does not affect the uEVs concentration, size, or tetraspanin profile. Among >6200 uEVs proteins identified, 43 define a panel significantly altered in HN patients without variation in urine, mostly annotated in the tubule (39 out of 43). The tubular transporter long-chain fatty acid transport protein 2 (SLC27A2) and the apical membrane protein amnionless (AMN) confirmed their alteration in HN patients evidencing impaired tubular reabsorption. SLC27A2 showed tubular expression and significantly reduced levels in patients with diagnostic criteria for CKD. Conclusions: Alterations in the EV-mediated molecular profile are evident before pathological ACR levels are reached. Direct quantitation of SLC27A2 and AMN in uEVs helps identifying normoalbuminuric subjects with higher cardiorenal risk in early monitoring of CKD.

Impact of inhibition of the renin-angiotensin system on early cardiac and renal abnormalities in Sprague Dawley rats fed short-term high fructose plus high salt diet.

Introduction: The combination of a high fructose and high salt diet typical of western diet induces high blood pressure, aortic stiffening, left ventricular (LV) diastolic dysfunction and impaired renal function in rodents. Despite an activated renin-angiotensin system (RAS) in rats fed high fructose and high salt, acute inhibition of the RAS pathway does not improve cardiac and vascular parameters. It may well be that longer term treatment is required to permit remodeling and improve cardiovascular function. Thus, we hypothesized that chronic RAS inhibition fructose+high salt-fed rats to restore blood pressure (BP) to levels similar to glucose plus normal salt-fed controls will improve cardiorenal function and histopathology. Methods: Male and female Sprague Dawley rats monitored by hemodynamic telemetry were fed 0.4% NaCl chow during baseline, then changed to chow containing either 20% glucose+0.4% NaCl (G) or 20% fructose+4% NaCl (F) and treated with vehicle, enalapril (Enal, 4 mg/kg/d) or losartan (Los, 8 mg/kg/d) by osmotic minipump for 25-26 days. Results: BP was elevated in the fructose+high salt groups of both sexes (P < 0.05) and restored to control levels by Enal or Los. Pulse wave velocity (PWV) was lower in female F+Los rats and cardiac output higher in female F+Enal rats. GFR was not changed by diet or treatment. Fructose+high salt groups of both sexes displayed higher albuminuria that was decreased by Enal in male rats. Cardiac fibrosis and mesangial hypercellularity were greater in fructose+high salt-fed rats of both sexes and improved with either Los or Enal. Discussion: Thus, inhibition of the RAS improves early changes in cardiac and renal histopathology in both sexes and albuminuria in male rats fed high fructose and high salt diet. Functional improvements in cardiorenal parameters may require longer treatment.

Proteomic Analysis Identifies Dysregulated Proteins in Albuminuria: A South African Pilot Study.

Albuminuria may precede decreases in the glomerular filtration rate (GFR) and both tests are insensitive predictors of early stages of kidney disease. Our aim was to characterise the urinary proteome in black African individuals with albuminuria and well-preserved GFR from South Africa. This case-controlled study compared the urinary proteomes of 52 normoalbuminuric (urine albumin: creatinine ratio (uACR) < 3 mg/mmol) and 56 albuminuric (uACR ≥ 3 mg/mmol) adults of black African ethnicity. Urine proteins were precipitated, reduced, alkylated, digested, and analysed using an Evosep One LC (Evosep Biosystems, Odense, Denmark) coupled to a Sciex 5600 Triple-TOF (Sciex, Framingham, MA, USA) in data-independent acquisition mode. The data were searched on SpectronautTM 15. Differentially abundant proteins (DAPs) were filtered to include those with a ≥2.25-fold change and a false discovery rate ≤ 1%. Receiver-operating characteristic curves were used to assess the discriminating abilities of proteins of interest. Pathway analysis was performed using Enrichr software. As expected, the albuminuric group had higher uACR (7.9 vs. 0.55 mg/mmol, p < 0.001). The median eGFR (mL/min/1.73 m2) showed no difference between the groups (111 vs. 114, p = 0.707). We identified 80 DAPs in the albuminuria group compared to the normoalbuminuria group, of which 59 proteins were increased while 21 proteins were decreased in abundance. We found 12 urinary proteins with an AUC > 0.8 and a p < 0.001 in the multivariate analysis. Furthermore, an 80-protein model was developed that showed a high AUC ˃ 0.907 and a predictive accuracy of 91.3% between the two groups. Pathway analysis found that the DAPs were involved in insulin growth factor (IGF) functions, innate immunity, platelet degranulation, and extracellular matrix organization. In albuminuric individuals with a well-preserved eGFR, pathways involved in preventing the release and uptake of IGF by insulin growth factor binding protein were significantly enriched. These proteins are indicative of a homeostatic imbalance in a variety of cellular processes underlying renal dysfunction and are implicated in chronic kidney disease.

Heart Failure Risk Prediction in a Population With a High Burden of Diabetes: Evidence From the Strong Heart Study.

BACKGROUND: Despite the high burden of diabetes and cardiovascular risk factors in American Indian communities in the United States, prospective studies of heart failure (HF) in this population group are scarce, and the generalizability of previous HF risk scales may be limited. We developed a parsimonious HF risk prediction equation that accounts for relevant risk factors affecting American Indian communities, focusing on diabetes and kidney damage. METHODS AND RESULTS: A total of 3059 participants from the SHS (Strong Heart Study) (56±8 years of age, 58% women) were included. Five hundred seven developed HF. Progressively adjusted Cox proportional hazards models were used to identify risk factors for HF and HF subtypes. Predictors of risk at 5 and 10 years included older age (hazard ratio [HR], 1.79 [95% CI, 1.43-2.25]; HR, 1.68 [95% CI, 1.44-1.95]), smoking (HR, 2.26 [95% CI, 1.23-4.13]; HR, 2.08 [95% CI, 1.41-3.06]), macroalbuminuria (HR, 8.38 [95% CI, 4.44-15.83]; HR, 5.20 [95% CI, 3.42-7.9]), microalbuminuria (HR, 2.72 [95% CI, 1.51-4.90]; HR, 1.92 [95% CI, 1.33, 2.78]), and previous myocardial infarction (HR, 6.58 [95% CI, 2.54-17.03]; HR, 3.87 [95% CI, 2.29-6.54]), respectively. These predictors, together with diabetes diagnosis and glycated hemoglobin were significant at 10 and 28 years. High discrimination performance was achieved (C index, 0.81 [95% CI, 0.76-0.84]; C index, 0.78 [95% CI, 0.75-0.81]; and C index, 0.77 [95% CI, 0.74-0.78] at 5, 10, and up to 28 years of follow up, respectively). Some associations varied across HF subtypes, although diabetes, albuminuria, and previous myocardial infarction were associated with all subtypes. CONCLUSIONS: This prospective study of HF risk factors in American Indian communities identifies that smoking, body mass index, and indicators of diabetes control and kidney damage (glycated hemoglobin and albuminuria) are major determinants of HF. Our findings can improve HF risk assessment in populations with a high burden of diabetes.