Biomarkers of renal injury and function: diagnostic, prognostic and therapeutic implications in heart failure

Clustering Based on Laboratory Data in Patients With Heart Failure Admitted to the Intensive Care Unit

BACKGROUND

Heart failure (HF) is a common condition that imposes a significant burden on healthcare systems. We aimed to identify subgroups of patients with heart failure admitted to the ICU using routinely measured laboratory biomarkers.

METHODS

A large dataset (N = 1176) of patients with heart failure admitted to the ICU at the Beth Israel Deaconess Medical Center in Boston, USA, between June 1, 2001, and October 31, 2012, was analyzed. We clustered patients to identify laboratory phenotypes. Cluster profiling was then performed to characterize each cluster, using a binary logistic model.

RESULTS

Two distinct clusters of patients were identified (N = 679 and 497). There was a significant difference in the mortality rate between Clusters 1 and 2 (50 [7.4%] vs. 109 [21.9%], respectively, p < 0.001). Patients in the Cluster 2 were significantly older (mean [SD] age = 72.35 [14.40] and 76.37 [11.61] years, p < 0.001) with a higher percentage of chronic kidney disease (167 [24.6%] vs. 262 [52.7%], respectively, p < 0.001). The logistic model was significant (Log-likelihood ratio p < 0.001, pseudo R2 = 0.746) with an area under the curve of 0.905. The odds ratio for leucocyte count, mean corpuscular volume (MCV), red blood cell (RBC) distribution width, hematocrit (HcT), lactic acid, blood urea nitrogen (BUN), serum potassium, magnesium, and sodium were significant (all p < 0.05).

CONCLUSION

Laboratory data revealed two phenotypes of ICU-admitted patients with heart failure. The two phenotypes are of prognostic importance in terms of mortality rate. They can be differentiated using blood cell count, kidney function status, and serum electrolyte concentrations.

Preclinical evaluation of 225Ac-labeled minigastrin analog DOTA-CCK-66 for Targeted Alpha Therapy

The recently developed metabolically more stable minigastrin derivative, DOTA-CCK-66, displayed promising preclinical data when labeled either with 68Ga or 177Lu. First positron emission tomography/computed tomography (PET/CT) imaging using [68Ga]Ga-DOTA-CCK-66 in two patients suffering from medullary thyroid carcinoma (MTC) displayed a favorable biodistribution profile. Here, we aim to investigate the therapeutic potential of [225Ac]Ac-DOTA-CCK-66 as a targeted α-therapy (TAT) agent in a comparative treatment study of [177Lu]Lu- versus [225Ac]Ac-DOTA-CCK-66.

METHODS

Treatment studies were performed (3 groups, n = 5, AR42J tumor-bearing 394-NOD SCID mice). Control group animals were injected with [68Ga]Ga-DOTA-CCK-66 (1.1 MBq, PET/CT imaging), while treatment group animals received a single dose of either [177Lu]Lu-DOTA-CCK-66 (37 MBq, radioligand therapy (RLT)) or [225Ac]Ac-DOTA-CCK-66 (37 kBq, TAT). All animals' tumor volume and body weight were monitored twice a week until end-point criteria were reached. Blood samples were evaluated (VetScan VS2, Abaxis) once mice were sacrificed.

RESULTS

Upon treatment, an initial decline in tumor volume, followed by a significantly delayed tumor growth of treated cohorts, was observed. Mean survival of 177Lu- as well as 225Ac-treated animals was increased by 3- (37 ± 3 d) and 4.5-fold (54 ± 6 d), respectively, when compared to non-treated animals (12 ± 3 d). Blood sample analysis did not indicate toxic side effects to the liver, kidney, or stomach upon 177Lu and 225Ac-treatment.

CONCLUSION

We demonstrated a substantial therapeutic efficacy of 177Lu- and 225Ac-labeled DOTA-CCK-66. As expected, treatment with the latter resulted in the highest mean survival rates. These results indicate a high therapeutic potential of 225Ac-labeled DOTA-CCK-66 for TAT in MTC patient management.

Sildenafil and furosemide nanoparticles as a novel pharmacological treatment for acute renal failure in rats

Hospitalized patients often develop acute renal failure (ARF), which causes severe morbidity and death. This research investigates the potential renoprotective benefits of sildenafil and furosemide in glycerol-induced ARF, and measures kidney function metrics in response to nanoparticle versions of these medications. Inducing ARF is commonly done by injecting 50% glycerol intramuscularly. Rats underwent a 24-h period of dehydration and starvation before slaughter for renal function testing. We investigated urine analysis, markers of oxidative stress, histology of kidney tissue, immunohistochemistry analysis of caspase-3 and interleukin-1 beta (IL-1 β), kidney injury molecule-1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL), which are specific indicators of kidney tissue damage. The results of our study showed that the combination of sildenafil and furosemide, using both traditional and nanoparticle formulations, had a greater protective effect on the kidneys compared to using either drug alone. The recovery of renal tissue indicators, serum markers, and urine markers, which are indicative of organ damage, provides evidence of improvement. This was also indicated by the reduction in KIM-1 and NGAL tubular expression. The immunohistochemistry tests showed that the combination therapy, especially with the nanoforms, greatly improved the damaged cellular changes in the kidneys, as shown by higher levels of caspase-3 and IL-1β. According to the findings, a glycerol-induced rat model demonstrates that sildenafil and furosemide, either alone or in combination, in conventional or nanoparticulate forms, improve ARF dysfunction. The synergistic nanoparticulate compositions show remarkable effectiveness. This observation highlights the possible therapeutic implications for ARF treatment.

Logistic regression model for predicting risk factors and contribution of cerebral microbleeds using renal function indicators

Background

The brain and kidneys share similar low-resistance microvascular structures, receiving blood at consistently high flow rates and thus, are vulnerable to blood pressure fluctuations. This study investigates the causative factors of cerebral microbleeds (CMBs), aiming to quantify the contribution of each risk factor by constructing a multivariate model via stepwise regression.

Methods

A total of 164 hospitalized patients were enrolled from January 2022 to March 2023 in this study, employing magnetic susceptibility-weighted imaging (SWI) to assess the presence of CMBs. The presence of CMBs in patients was determined by SWI, and history, renal function related to CMBs were analyzed.

Results

Out of 164 participants in the safety analysis, 36 (21.96%) exhibited CMBs and 128 (78.04%) did not exhibit CMBs, and the median age of the patients was 66 years (range: 49-86 years). Multivariate logistic regression identified hypertension (OR = 13.95%, 95% CI: 4.52, 50.07%), blood urea nitrogen (BUN) (OR = 1.57, 95% CI: 1.06-2.40), cystatin C (CyC) (OR = 4.90, 95% CI: 1.20-22.16), and urinary β-2 microglobulin, (OR = 2.11, 95% CI: 1.45-3.49) as significant risk factors for CMBs. The marginal R-square (R M 2 ) was 0.25. Among all determinants, hypertension (47.81%) had the highest weight, followed by UN (11.42%). Quasi-curves plotted using the bootstrap method (999 times) showed good agreement between the predictive model and actual observations.

Conclusion

Hypertension, BUN, urinary β-2 microglobulin, CyC were risk factors for CMBs morbidity, and controlling the above indicators within a reasonable range will help to reduce the incidence of CMBs.

Role of Noninvasive Urinary Prothrombin Fragment 1 + 2 to Measure Blood Coagulation Indices and Dose of Acenocoumarol

PF1 + 2 plasma levels are a crucial indicator for assessing anticoagulant action in individuals receiving anticoagulant treatment. Urine also has PF1 + 2 levels due to its molecular size. Hence, the present study aims to measure urinary prothrombin fragment 1 + 2 (uPF1 + 2) in patients taking anticoagulants in order to divulge a noninvasive surrogate marker of PT-INR of blood coagulopathy. A total of 205 people participated in the study: 104 patients on acenocoumarol (AC) and 101 healthy controls (HC). Clinical parameters, including PT-INR, urinary creatinine, etc., were measured in all subjects. To evaluate uPF1 + 2 in samples, MALDI-TOF-MS, Western blot analysis, and ELISA tests were used. The MALDI-TOF-MS results showed the presence of uPF1 + 2 in both AC and HC urine samples. The Western blot, ELISA experiment, and unpaired t test results displayed that the patients with AC had significantly increased levels of uPF1 + 2 compared to HC. A regression study showed a strong positive relation between blood-based PT-INR and uPF1 + 2. ROC validation also revealed the clinical efficacy of uPF1 + 2. For the goal to monitor anticoagulant medication, the present study highlights PF1 + 2, which describes the overall hemostatic capacity and might be utilized in addition to or instead of PT-INR.

Renal ultrasonography predicts worsening renal function in patients with heart failure under tolvaptan administration

AIMS

Renal dysfunction in patients with chronic heart failure predicts a poor prognosis. Tolvaptan has a diuretic effect in patients with chronic kidney disease and heart failure without adverse effects on renal function. We aimed to determine the effects of tolvaptan and predictors of worsening renal function in patients with heart failure.

METHODS AND RESULTS

This post hoc analysis was a sub-analysis of a single-centre prospectively randomized trial on the early and short-term tolvaptan administration. We enrolled 201 participants with decompensated heart failure between January 2014 and March 2019 (early group, n = 104; age: 79.0 ± 12.8 years; late group, n = 97; age: 80.3 ± 10.8 years). Renal ultrasonography was performed before and after the administration of tolvaptan. Urine output and oral water intake significantly increased during tolvaptan administration. The difference between water intake and urine volume increased during tolvaptan administration. Changes in body weight, blood pressure, heart rate, and estimated glomerular filtration rate (eGFR) in both groups were comparable. The changes in peak-systolic velocity (PSV), acceleration time (AT) of the renal arteries, and resistance index were comparable. The changes in PSV and end-diastolic velocity (EDV) of the interlobar arteries increased following tolvaptan administration (Δmax PSV: 0.0 ± 14.8 cm/s before tolvaptan vs. 5.6 ± 15.7 cm/s after tolvaptan, P = 0.002; Δmean PSV: 0.4 ± 12.3 vs. 4.9 ± 12.7 cm/s, P = 0.002; Δmax EDV: -0.2 ± 3.5 vs. 1.4 ± 4.0 cm/s, P = 0.001; Δmean EDV: -0.0 ± 3.1 vs. 1.1 ± 3.4 cm/s, P = 0.003). The renal artery AT was negatively correlated with the eGFR (Δmax AT: beta = -0.2354, P = 0.044; Δmean AT: beta = -0.2477, P = 0.035).

CONCLUSIONS

Tolvaptan increased the PSV and EDV of the interlobar artery, which may mean tolvaptan increased renal blood flow. The renal artery AT may be a surrogate for worsening renal function.

The long-term effects of blood urea nitrogen levels on cardiovascular disease and all-cause mortality in diabetes: a prospective cohort study

BACKGROUND

The long-term effects of blood urea nitrogen(BUN) in patients with diabetes remain unknown. Current studies reporting the target BUN level in patients with diabetes are also limited. Hence, this prospective study aimed to explore the relationship of BUN with all-cause and cardiovascular mortalities in patients with diabetes.

METHODS

In total, 10,507 participants with diabetes from the National Health and Nutrition Examination Survey (1999-2018) were enrolled. The causes and numbers of deaths were determined based on the National Death Index mortality data from the date of NHANES interview until follow-up (December 31, 2019). Multivariate Cox proportional hazard regression models were used to calculate the hazard ratios (HRs) and 95% confidence interval (CIs) of mortality.

RESULTS

Of the adult participants with diabetes, 4963 (47.2%) were female. The median (interquartile range) BUN level of participants was 5 (3.93-6.43) mmol/L. After 86,601 person-years of follow-up, 2,441 deaths were documented. After adjusting for variables, the HRs of cardiovascular disease (CVD) and all-cause mortality in the highest BUN level group were 1.52 and 1.35, respectively, compared with those in the lowest BUN level group. With a one-unit increment in BUN levels, the HRs of all-cause and CVD mortality rates were 1.07 and 1.08, respectively. The results remained robust when several sensitivity and stratified analyses were performed. Moreover, BUN showed a nonlinear association with all-cause and CVD mortality. Their curves all showed that the inflection points were close to the BUN level of 5 mmol/L.

CONCLUSION

BUN had a nonlinear association with all-cause and CVD mortality in patients with diabetes. The inflection point was at 5 mmol/L.

Urinary Marker Profiles in Heart Failure with Reduced Versus Preserved Ejection Fraction

BACKGROUND

Recent data suggest different causes of renal dysfunction between heart failure with reduced (HFrEF) versus preserved ejection fraction (HFpEF). We therefore studied a wide range of urinary markers reflecting different nephron segments in heart failure patients.

METHODS

In 2070, in chronic heart failure patients, we measured several established and upcoming urinary markers reflecting different nephron segments.

RESULTS

Mean age was 70 ± 12 years, 74% was male and 81% (n = 1677) had HFrEF. Mean estimated glomerular filtration rate (eGFR) was lower in patients with HFpEF (56 ± 23 versus 63 ± 23 ml/min/1.73 m2, P = 0.001). Patients with HFpEF had significantly higher values of NGAL (58.1 [24.0-124.8] versus 28.1 [14.6-66.9] μg/gCr, P < 0.001) and KIM-1 (2.28 [1.49-4.37] versus 1.79 [0.85-3.49] μg/gCr, P = 0.001). These differences were more pronounced in patients with an eGFR > 60 ml/min/1.73m2.

CONCLUSIONS

HFpEF patients showed more evidence of tubular damage and/or dysfunction compared with HFrEF patients, in particular when glomerular function was preserved.

Research-based Analytical Procedures to Evaluate Diabetic Biomarkers and Related Parameters: In Vitro and In Vivo Methods

BACKGROUND

The degenerative tendency of diabetes leads to micro- and macrovascular complications due to abnormal levels of biochemicals, particularly in patients with poor diabetic control. Diabetes is supposed to be treated by reducing blood glucose levels, scavenging free radicals, and maintaining other relevant parameters close to normal ranges. In preclinical studies, numerous in vivo trials on animals as well as in vitro tests are used to assess the antidiabetic and antioxidant effects of the test substances. Since a substance that performs poorly in vitro won't perform better in vivo, the outcomes of in vitro studies can be utilized as a direct indicator of in vivo activities.

OBJECTIVE

The objective of the present study is to provide research scholars with a comprehensive overview of laboratory methods and procedures for a few selected diabetic biomarkers and related parameters.

METHOD

The search was conducted on scientific database portals such as ScienceDirect, PubMed, Google Scholar, BASE, DOAJ, etc. Conclusion: The development of new biomarkers is greatly facilitated by modern technology such as cell culture research, lipidomics study, microRNA biomarkers, machine learning techniques, and improved electron microscopies. These biomarkers do, however, have some usage restrictions. There is a critical need to find more accurate and sensitive biomarkers. With a few modifications, these biomarkers can be used with or even replace conventional markers of diabetes.

Design and development of opto-electrochemical biosensing devices for diagnosing chronic kidney disease

Chronic kidney disease (CKD) is emerging as one of the major causes of the increase in mortality rate and is expected to become 5th major cause by 2050. Many studies have shown that it is majorly related to various risk factors, and thus becoming one of the major health issues around the globe. Early detection of renal disease lowers the overall burden of disease by preventing individuals from developing kidney impairment. Therefore, diagnosis and prevention of CKD are becoming the major challenges, and in this situation, biosensors have emerged as one of the best possible solutions. Biosensors are becoming one of the preferred choices for various diseases diagnosis as they provide simpler, cost-effective and precise methods for onsite detection. In this review, we have tried to discuss the globally developed biosensors for the detection of CKD, focusing on their design, pattern, and applicability in real samples. Two major classifications of biosensors based on transduction systems, that is, optical and electrochemical, for kidney disease have been discussed in detail. Also, the major focus is given to clinical biomarkers such as albumin, creatinine, and others related to kidney dysfunction. Furthermore, the globally developed sensors for the detection of CKD are discussed in tabulated form comparing their analytical performance, response time, specificity as well as performance in biological fluids.

Biomarkers in Heart Failure: From Research to Clinical Practice

The aim of this narrative review is to summarize contemporary evidence on the use of circulating cardiac biomarkers of heart failure (HF) and to identify a promising biomarker model for clinical use in personalized point-of-care HF management. We discuss the reported biomarkers of HF classified into clusters, including myocardial stretch and biomechanical stress; cardiac myocyte injury; systemic, adipocyte tissue, and microvascular inflammation; cardiac fibrosis and matrix remodeling; neurohumoral activation and oxidative stress; impaired endothelial function and integrity; and renal and skeletal muscle dysfunction. We focus on the benefits and drawbacks of biomarker-guided assistance in daily clinical management of patients with HF. In addition, we provide clear information on the role of alternative biomarkers and future directions with the aim of improving the predictive ability and reproducibility of multiple biomarker models and advancing genomic, transcriptomic, proteomic, and metabolomic evaluations.

Development and validation of a survival prediction model in elder patients with community-acquired pneumonia: a MIMIC-population-based study

BACKGROUND

To develop a prediction model predicting in-hospital mortality of elder patients with community-acquired pneumonia (CAP) admitted to the intensive care unit (ICU).

METHODS

In this cohort study, data of 619 patients with CAP aged ≥ 65 years were obtained from the Medical Information Mart for Intensive Care III (MIMIC III) 2001-2012 database. To establish the robustness of predictor variables, the sample dataset was randomly partitioned into a training set group and a testing set group (ratio: 6.5:3.5). The predictive factors were evaluated using multivariable logistic regression, and then a prediction model was constructed. The prediction model was compared with the widely used assessments: Sequential Organ Failure Assessment (SOFA), Pneumonia Severity Index (PSI), systolic blood pressure, oxygenation, age and respiratory rate (SOAR), CURB-65 scores using positive predictive value (PPV), negative predictive value (NPV), accuracy (ACC), area under the curve (AUC) and 95% confidence interval (CI). The decision curve analysis (DCA) was used to assess the net benefit of the prediction model. Subgroup analysis based on the pathogen was developed.

RESULTS

Among 402 patients in the training set, 90 (24.63%) elderly CAP patients suffered from 30-day in-hospital mortality, with the median follow-up being 8 days. Hemoglobin/platelets ratio, age, respiratory rate, international normalized ratio, ventilation use, vasopressor use, red cell distribution width/blood urea nitrogen ratio, and Glasgow coma scales were identified as the predictive factors that affect the 30-day in-hospital mortality. The AUC values of the prediction model, the SOFA, SOAR, PSI and CURB-65 scores, were 0.751 (95% CI 0.749-0.752), 0.672 (95% CI 0.670-0.674), 0.607 (95% CI 0.605-0.609), 0.538 (95% CI 0.536-0.540), and 0.645 (95% CI 0.643-0.646), respectively. DCA result demonstrated that the prediction model could provide greater clinical net benefits to CAP patients admitted to the ICU. Concerning the pathogen, the prediction model also reported better predictive performance.

CONCLUSION

Our prediction model could predict the 30-day hospital mortality in elder patients with CAP and guide clinicians to identify the high-risk population.

Resolvin D5 (RvD5) Reduces Renal Damage Caused by LPS Endotoxemia in Female Mice

In self-revolving gram-negative Escherichia coli infection, Resolvin D5 (RvD5) was found to enhance bacteria phagocytosis and reduce the production of inflammatory mediators, contributing to the resolution of infection. LPS (lipopolysaccharide) is a gram-negative bacterial structure product which activates the immune system and, at high doses, leads to endotoxemia. To our knowledge, the effect of RvD5 against LPS endotoxemia has not been investigated to date. Female Swiss mice received an i.p. treatment with RvD5 (0.1, 1 or 10 ng/animal). After 1 h, they were stimulated with LPS (10 mg/kg, i.v.), and samples were collected after additional 6 h. The resulting data demonstrated that RvD5 protected the kidneys (urea and creatinine serum levels) from tissue injury. These effects were related to an improvement in histopathological parameters and a reduction of enzymatic markers of leukocyte infiltration, pro-inflammatory cytokine (IL-1β, TNF-α, and IL-6) production, and oxidative stress. Antioxidant markers were also increased by RvD5, but IL-10 (an anti-inflammatory cytokine) levels were unaltered. We also observed that RvD5 reduced the infiltration of CD45⁺ hematopoietic cells into the kidneys, reduced the activation of NFκB and promoted the Nrf2 pathway by reducing Keap-1 levels. Our data indicate that RvD5 may be a therapeutic possibility to reduce kidney lesions in LPS endotoxemia.

Short-term exposure to fine particulate matter and its constituents may affect renal function via oxidative stress: A longitudinal panel study

Exposure to fine particulate matter (PM_2.5) has been reported to increase the risks of chronic kidney disease. However, limited research has assessed the effect of PM_2.5 and its constituents on renal function, and the underlying mechanism has not been well characterized. We aimed to evaluate the association of PM_2.5 and its constituents with kidney indicators and to explore the roles of systematic oxidative stress and inflammation in the association. We conducted a longitudinal panel study among 35 healthy adults before-, intra- and after-the 2019 Wuhan Military World Games. We repeatedly measured 6 renal function parameters and 5 circulating biomarkers of oxidative stress and inflammation at 6 rounds of follow-ups. We monitored hourly personal PM_2.5 concentrations with 3 consecutive days and measured 10 metals (metalloids) and 16 polycyclic aromatic hydrocarbons (PAHs) components. The linear mixed-effect models were applied to examine the association between PM_2.5 and renal function parameters, and the mediation analysis was performed to explore potential bio-pathways. PM_2.5 concentrations across Wuhan showed a slight decrease during the Military Games. We observed significant associations between elevated blood urea nitrogen (BUN) levels and PM_2.5 and its several metals and PAHs components. For an interquartile range (IQR) increase of PM_2.5, BUN increased 0.42 mmol/L (95% CI: 0.14 to 0.69). On average, an IQR higher of lead (Pb), cadmium (Cd), arsenic (As), selenium (Se), thallium (Tl) and Indeno (1,2,3-cd) pyrene (IPY) were associated with 0.90, 0.65, 0.29, 0.27, 0.26 and 0.90 mmol/L increment of BUN, respectively. Moreover, superoxide dismutase was positively associated with PM_2.5 and mediated 18.24% association. Our research indicated that exposure to PM_2.5 might affect renal function by activating oxidative stress pathways, in which the constituents of Pb, Cd, As, Se, Tl and IPY might contribute to the associations.

The blood urea nitrogen/creatinine (BUN/cre) ratio was U-shaped associated with all-cause mortality in general population

Objectives

This study aimed to explore the relationship between the blood urea nitrogen/creatinine (BUN/Cre) ratio and all-cause or cause-specific mortality in the general population.

Methods

Participants were enrolled from the National Health and Nutrition Examination Survey (NHANES) during 1999 to 2014. Baseline variables were acquired from questionnaires and examinations. Death status were ascertained from National Death Index records. Cox proportional hazards models with cubic spines were used to estimate hazard ratios (HRs) and 95% confidence interval (CI) of all-cause mortality, cardiovascular and cancer mortality.

Results

A total of 42038 participants were enrolled in the study with a median 8.13 years of follow-up. Older people and women tend to have a higher BUN/Cre ratio. After multivariable adjustment, BUN/Cre ratio between 11.43 and 14.64 was associated with the lowest all-cause mortality compared with the participants with the lowest quartile (HR 0.83 [0.76, 0.91]; p < 0.001). The highest quartile of BUN/Cre ratio was associated with the lowest risk of cancer mortality (HR 0.64 [0.53, 0.78]; p < 0.001). Restricted cubic splines showed BUN/Cre was nonlinearly associated with all-cause mortality and linearly associated with cancer mortality.

Conclusions

This study confirmed a U-shape relationship between BUN/Cre ratio and all-cause mortality in the general population.

Blood urea nitrogen to serum albumin ratio as a new prognostic indicator in critical patients with chronic heart failure

Aims

Chronic heart failure (CHF) is often a common comorbidity in critically ill patients admitted to the intensive care unit (ICU) and carries an extremely poor prognosis. The study aimed to investigate the relationship between the blood urea nitrogen to serum albumin ratio (BAR) and the prognosis of patients with CHF admitted to the ICU.

Methods and results

This retrospective cohort study included 1545 critically ill patients with CHF as a diagnosed comorbidity admitted to the ICU deposited in the MIMIC‐III database, of whom 90 day all‐cause mortality was 27.6% (n = 427) and in‐hospital mortality was 17.3% (n = 267). The results of multiple logistic regression analysis indicated that BAR is an independent risk factor for in‐hospital mortality in critically ill patients with CHF [compared with BAR ≤ 0.83; 0.83 < BAR ≤ 1.24: odds ratio (OR) 2.647, 95% confidence interval (CI) 1.797–3.900, P < 0.001; BAR ≥ 1.24: OR 3.628, 95% CI 2.604–5.057, P < 0.001]. Multiple COX regression analysis found a relationship between BAR and all‐cause mortality at 90 day follow‐up (0.83 < BAR ≤ 1.24: OR 1.948, 95% CI 1.259–3.014, P < 0.003; BAR ≥ 1.24: OR 1.807, 95% CI 1.154–2.830, P < 0.01; BAR ≤ 0.83 as a reference). Kaplan–Meier curves also showed similar results as well (P < 0.001). The areas under the receiver operating characteristic curves for predicting in‐hospital mortality and 90 day all‐cause mortality were 0.622 and 0.647, respectively.

Conclusions

BAR is an independent risk factor for in‐hospital mortality and 90 day mortality in critically ill patients with CHF admitted to the ICU.

Cause of Death in Heart Failure Based on Etiology: Long-Term Cohort Study of All-Cause and Cardiovascular Mortality

We assessed differences in long-term all-cause and cardiovascular (CV) mortality in heart failure (HF) outpatients based on the etiology of HF. Consecutive patients admitted to the HF Clinic from August 2001 to September 2019 (N = 2587) were considered for inclusion. HF etiology was divided into ischemic heart disease (IHD), dilated cardiomyopathy (DCM), hypertensive heart disease, alcoholic cardiomyopathy, drug-induced cardiomyopathy (DICM), valvular heart disease, and hypertrophic cardiomyopathy. All-cause death and CV death were the primary end points. Among 2387 patients included in the analysis (mean age 66.5 ± 12.5 years, 71.3% men), 1317 deaths were recorded (731 from CV cause) over a maximum follow-up of 18 years (median 4.1 years, interquartile range (IQR) 2–7.8). Considering IHD as the reference, only DCM had a lower risk of all-cause death (adjusted hazard ratio (aHR) 0.68, 95% confidence interval (CI) 0.56–0.83, p < 0.001), and only DICM had a higher risk of all-cause death (aHR 1.47, 95% CI 1.02–2.11, p = 0.04). However, almost all etiologies had a significantly lower risk of CV death than IHD. Among the studied HF etiologies, DCM and DICM have the lowest and highest risk of all-cause death, respectively, whereas IHD has the highest adjusted risk of CV death.

Dehydration Status Aggravates Early Renal Impairment in Children: A Longitudinal Study

Dehydration is common in children for physiological and behavioral reasons. The objective of this study was to assess changes in hydration status and renal impairment across school weekdays. We conducted a longitudinal study of three repeated measures of urinalysis within one week in November 2019 in a child cohort in Beijing, China. We measured urine specific gravity (USG) to determine the dehydration status, and the concentration of β₂-microglobulin (β₂-MG) and microalbumin (MA) to assess renal function impairment among 1885 children with a mean age of 7.7 years old. The prevalence of dehydration was 61.9%, which was significantly higher in boys (64.3%). Using chi-square tests and linear mixed-effects regression models, we documented the trends of the renal indicators’ change over time among different hydration statuses. Compared to Mondays, there were apparent increases of β₂-MG concentrations on Wednesdays (β = 0.029, p < 0.001) and Fridays (β = 0.035, p < 0.001) in the dehydrated group, but not in the euhydrated group. As for the MA concentrations, only the decrease on Fridays (β = −1.822, p = 0.01) was significant in the euhydrated group. An increased trend of elevated β₂-MG concentration was shown in both the euhydrated group (Z = −3.33, p < 0.001) and the dehydrated group (Z = −8.82, p < 0.001). By contrast, there was a decreased trend of elevated MA concentrations in the euhydrated group (Z = 3.59, p < 0.001) but not in the dehydrated group. A new indicator ratio, β₂-MG/MA, validated the consistent trends of renal function impairment in children with dehydration. Renal impairment trends worsened as a function of school days during the week and the dehydration status aggravated renal impairment during childhood across school weekdays, especially tubular abnormalities in children.

Urinary liver-type fatty acid-binding protein as a prognostic marker in patients with acute heart failure

Aims

Urinary liver‐type fatty acid‐binding protein (L‐FABP) is expressed in proximal tubular epithelial cells and excreted into the urine during tubular injury. We hypothesized that high urinary L‐FABP is associated with poor prognosis in patients with acute heart failure (AHF).

Methods and results

We analysed 623 patients (74 ± 13 years old; 60.0% male patients) with AHF. Urinary L‐FABP levels were measured at the time of admission and adjusted for the urinary creatinine concentration. The primary endpoint was all‐cause mortality. The median value and interquartile range of urinary L‐FABP levels were 6.66 and 3.37–21.1 μg/gCr, respectively. Urinary L‐FABP levels were significantly correlated with both beta‐2 microglobulin and cystatin C levels; the correlation with the former was higher than that with the latter. During the follow‐up of 631 (interquartile range: 387–875) days, 142 deaths occurred. A high tertile of urinary L‐FABP level was associated with high mortality; this association was retained after adjusting for other covariates (second tertile hazard ratio 1.40, P = 0.152 vs. first tertile; third tertile hazard ratio 1.94, P = 0.005 vs. first tertile).

Conclusions

Urinary L‐FABP is more closely associated with tubular dysfunction than with glomerular dysfunction. Tubular dysfunction, which was evaluated based on urinary L‐FABP levels, in patients with AHF is associated with all‐cause mortality and is independent of pre‐existing risk factors. L‐FABP should be considered for use in the prognosis of AHF.

Proenkephalin and the risk of new-onset heart failure: data from prevention of renal and vascular end-stage disease

Background

Enkephalins of the opioid system exert several cardiorenal effects. Proenkephalin (PENK), a stable surrogate, is associated with heart failure (HF) development after myocardial infarction and worse cardiorenal function and prognosis in patients with HF. The association between plasma PENK concentrations and new‐onset HF in the general population remains to be established.

Hypothesis

We hypothesized that plasma PENK concentrations are associated with new‐onset HF in the general population.

Methods

We included 6677 participants from the prevention of renal and vascular end‐stage disease study and investigated determinants of PENK concentrations and their association with new‐onset HF (both reduced [HFrEF] and preserved ejection fraction [HFpEF]).

Results

Median PENK concentrations were 52.7 (45.1–61.9) pmol/L. Higher PENK concentrations were associated with poorer renal function and higher NT‐proBNP concentrations. The main determinants of higher PENK concentrations were lower estimated glomerular filtration rate (eGFR), lower urinary creatinine excretion, and lower body mass index (all p < .001). After a median 8.3 (7.8–8.8) years follow‐up, 221 participants developed HF; 127 HFrEF and 94 HFpEF. PENK concentrations were higher in subjects who developed HF compared with those who did not, 56.2 (45.2–67.6) versus 52.7 (45.1–61.6) pmol/L, respectively (p = .003). In competing‐risk analyses, higher PENK concentrations were associated with higher risk of new‐onset HF (hazard ratio [HR] = 2.09[1.47–2.97], p < .001), including both HFrEF (HR = 2.31[1.48–3.61], p < .001) and HFpEF (HR = 1.74[1.02–2.96], p = .042). These associations were, however, lost after adjustment for eGFR.

Conclusions

In the general population, higher PENK concentrations were associated with lower eGFR and higher NT‐proBNP concentrations. Higher PENK concentrations were not independently associated with new‐onset HFrEF and HFpEF and mainly confounded by eGFR.

Impact of glomerular filtration rate estimation on cardiovascular events in elderly patients undergoing coronary angiography

BACKGROUND

Estimation of kidney function by glomerular filtration rate (eGFR) is affected by age and is important for decision making regarding treatment and prognosis of patients with cardiovascular disease. We investigated the impact of eGFR on long-term cardiovascular outcomes in an elderly population undergoing coronary angiography for evaluation or treatment of coronary artery disease.

METHODS

GFR was estimated according to Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation in 3690 elderly patients (aged 70-100 years) undergoing coronary angiography. Patients receiving maintenance dialysis were excluded. The association between eGFR and major adverse cardiovascular events (MACE) including myocardial infarction, ischemic stroke or death, was investigated. GFR was further calculated according to modification of diet in renal disease (MDRD) and the Cockcroft-Gault equations, and compatibility between estimations was analyzed.

RESULTS

Cardiovascular comorbidities were more prevalent with the reduction in kidney function as was the proportion of patients presenting with acute coronary syndromes. The adjusted hazard ratio (95% confidence interval) for MACE during a mean follow-up of 5 years was 0.95 (0.77-1.16), 1.04 (0.84-1.29), 1.56 (1.16-1.84), 2.22 (1.65-2.97) and 3.74 (2.20-6.38) in patients with eGFR 60-89, 45-59, 30-44, 15-29 and <15 ml/min/1.73m2, respectively, compared to >90 ml/min/1.73m2. Reclassification of eGFR stages by MDRD (upward 23.8%, downward 0.4%) and Cockcroft-Gault (upward 4.3%, downward 28.1%) compared to CKD-EPI estimation, was noted. However, the association between eGFR stages and MACE was similar between equations.

CONCLUSIONS

Kidney function, as manifested by eGFR, has a graded inverse association with the burden of cardiovascular comorbidities and long-term adverse events in elderly patients undergoing coronary angiography.

Urinary FABP1 is a biomarker for impaired proximal tubular protein reabsorption and is synergistically enhanced by concurrent liver injury

Urinary fatty acid binding protein 1 (FABP1, also known as liver‐type FABP) has been implicated as a biomarker of acute kidney injury (AKI) in humans. However, the precise biological mechanisms underlying its elevation remain elusive. Here, we show that urinary FABP1 primarily reflects impaired protein reabsorption in proximal tubule epithelial cells (PTECs). Bilateral nephrectomy resulted in a marked increase in serum FABP1 levels, suggesting that the kidney is an essential organ for removing serum FABP1. Injected recombinant FABP1 was filtered through the glomeruli and robustly reabsorbed via the apical membrane of PTECs. Urinary FABP1 was significantly elevated in mice devoid of megalin, a giant endocytic receptor for protein reabsorption. Elevation of urinary FABP1 was also observed in patients with Dent disease, a rare genetic disease characterized by defective megalin function in PTECs. Urinary FABP1 levels were exponentially increased following acetaminophen overdose, with both nephrotoxicity and hepatotoxicity observed. FABP1‐deficient mice with liver‐specific overexpression of FABP1 showed a massive increase in urinary FABP1 levels upon acetaminophen injection, indicating that urinary FABP1 is liver‐derived. Lastly, we employed transgenic mice expressing diphtheria toxin receptor (DT‐R) either in a hepatocyte‐ or in a PTEC‐specific manner, or both. Upon administration of diphtheria toxin (DT), massive excretion of urinary FABP1 was induced in mice with both kidney and liver injury, while mice with either injury type showed marginal excretion. Collectively, our data demonstrated that intact PTECs have a considerable capacity to reabsorb liver‐derived FABP1 through a megalin‐mediated mechanism. Thus, urinary FABP1, which is synergistically enhanced by concurrent liver injury, is a biomarker for impaired protein reabsorption in AKI. These findings address the use of urinary FABP1 as a biomarker of histologically injured PTECs that secrete FABP1 into primary urine, and suggest the use of this biomarker to simultaneously monitor impaired tubular reabsorption and liver function. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Therapeutic Potential of Extracellular Vesicles for Sepsis Treatment

Sepsis is a deadly condition lacking a specific treatment despite decades of research. This has prompted the exploration of new approaches, with extracellular vesicles (EVs) emerging as a focal area. EVs are nanosized, cell-derived particles that transport bioactive components (i.e., proteins, DNA, and RNA) between cells, enabling both normal physiological functions and disease progression depending on context. In particular, EVs have been identified as critical mediators of sepsis pathophysiology. However, EVs are also thought to constitute the biologically active component of cell-based therapies and have demonstrated anti-inflammatory, anti-apoptotic, and immunomodulatory effects in sepsis models. The dual nature of EVs in sepsis is explored here, discussing their endogenous roles and highlighting their therapeutic properties and potential. Related to the latter component, prior studies involving EVs from mesenchymal stem/stromal cells (MSCs) and other sources are discussed and emerging producer cells that could play important roles in future EV-based sepsis therapies are identified. Further, how methodologies could impact therapeutic development toward sepsis treatment to enhance and control EV potency is described.

Association between early worsening of kidney function and poor outcomes in patients treated with renin angiotensin system inhibitors: A meta-analysis

AIM

As renin angiotensin system inhibitors (RASi) are widely used in the clinic, early worsening of kidney function (EWKF) after RASi therapy deserves attention, as its clinical significance is unknown. The aim was to evaluate the relationship between EWKF and long-term outcomes including all-cause mortality, kidney and cardiovascular events, in all the patients treated with RASi.

METHODS

We searched PubMed, Embase, and the Cochrane databases for controlled trials that compared the outcomes of patients with and without EWKF after RASi treatment. Our primary outcome was all-cause mortality, and secondary outcomes were kidney and cardiovascular events. We pooled data using a random effects model.

RESULTS

A total of ten studies were enrolled, of which eight were randomized trials (including 33 454 patients) and two were observational studies (including 148 144 patients). Of the eight randomized trials, 4996 patients with type 2 diabetes, 19 118 with heart failure (HF), and 9340 with atherosclerotic vascular disease and diabetes with end-organ damage. Both observational studies investigated all kinds of patients with initial RASi treatment. In patients with RASi, the EWKF group had a higher risk of all-cause mortality than the no-EWKF group in the randomized studies (n =  13 581; RR, 1.22; 95% CI, 1.04-1.42; P = .02) and in observational studies (n = 148 144; OR, 1.70; 95% CI, 1.43-2.01; P < .00001). In patients who experienced EWKF, no statistically significant difference was found between the efficacy of RASi and placebo in all-cause mortality (n = 1762; RR, 0.85; 95% CI, 0.68-1.06; P = .14).

CONCLUSION

RASi treatment led to an increased incidence of EWKF which was associated with poorer long-term outcomes. As the benefit of RAS blockade to patients with EWKF was limited, we suggest clinicians use RASi with caution when EWKF occurs.

Nomenclature for Kidney Function from KDIGO: Shortcomings of Terminology Oversimplification

The recent Kidney Disease: Improving Global Outcomes (KDIGO) consensus conference proposed a universal nomenclature calling for "Kidney Disease" (KD) to be applied to every form of kidney dysfunction, regardless of etiology. We recognize that the estimated glomerular filtration rate and urine albumin:creatinine ratio are limited in their application to the broad spectrum of KD. However, there are additional in vitro and advanced diagnostic options that can help identify the underlying cause of KD and inform about prognosis and management. While the overarching benefit of generalizing KD as a medical problem lies with screening and detection, the downsides attributable to a nonexact diagnosis (i.e., unclear prognosis and management strategy) are considerable. Finally, the terms "acute kidney injury" and "worsening renal function" are currently used interchangeably by nephrologists and cardiologists alike, and a universal adoption of one term will likely be a sizeable challenge. To be of greater benefit, we propose KD be used as a starting point and that the etiology and other epigenetic determinants of illness continue to be evaluated and characterized.

Age- and sex-specific reference intervals for blood urea nitrogen in Chinese general population

Blood urea nitrogen (BUN) is a nitrogenous end product of protein metabolism. This study aims to explore the age- and sex-specific distribution of BUN among healthy Chinese adults. A total of 24,006 BUN values from healthy adults (14,148 males and 9858 females) were included in the cross-sectional study. Males had a higher median BUN value compared to females (4.6 mmol/L vs. 4.1 mmol/L). BUN values showed a positive correlation with body mass index (BMI), cholesterol, and blood sugar (P < 0.0001). However, eGFR showed a negative correlation with the BUN reference value (P < 0.0001) in both sexes. Multiple linear regression analysis confirmed that the positive associations of BUN levels and age were statistically significant after adjusting confounding factors (P < 0.001). Thus, the serum BUN values increased by 0.21 mmol/L for males and 0.282 mmol/L for females per 10 years. The BUN values corresponding to the 1st, 2.5th, 50th, 97.5th, and 99th percentiles for any specific age in both sex were also calculated. These results indicate that the serum BUN reference value is significantly affected by age and gender, and thus, its interpretation is age- and sex-dependent.

Potential Utility of Cardiorenal Biomarkers for Prediction and Prognostication of Worsening Renal Function in Acute Heart Failure

BACKGROUND

Multiple different pathophysiologic processes can contribute to worsening renal function (WRF) in acute heart failure.

METHODS AND RESULTS

We retrospectively analyzed 787 patients with acute heart failure for the relationship between changes in serum creatinine and biomarkers including brain natriuretic peptide, high sensitivity cardiac troponin I, galectin 3, serum neutrophil gelatinase-associated lipocalin, and urine neutrophil gelatinase-associated lipocalin. WRF was defined as an increase of greater than or equal to 0.3 mg/dL or 50% in creatinine within first 5 days of hospitalization. WRF was observed in 25% of patients. Changes in biomarkers and creatinine were poorly correlated (r ≤ 0.21) and no biomarker predicted WRF better than creatinine. In the multivariable Cox analysis, brain natriuretic peptide and high sensitivity cardiac troponin I, but not WRF, were significantly associated with the 1-year composite of death or heart failure hospitalization. WRF with an increasing urine neutrophil gelatinase-associated lipocalin predicted an increased risk of heart failure hospitalization.

CONCLUSIONS

Biomarkers were not able to predict WRF better than creatinine. The 1-year outcomes were associated with biomarkers of cardiac stress and injury but not with WRF, whereas a kidney injury biomarker may prognosticate WRF for heart failure hospitalization.

Kidney Function Following Left Ventricular Assist Device Implantation: An Observational Cohort Study

Rationale & Objective

Nearly half the patients with heart failure have chronic kidney disease. Implantation of a left ventricular assist device (LVAD) improves kidney function in some but not all patients, and lack of improvement is associated with worse outcomes. Preimplantation factors that predict change in kidney function after LVAD placement are not well described.

Study Design

Single-center observational study.

Setting & Participants

Consecutive patients undergoing LVAD implantation.

Predictors

48 diverse preimplantation variables including demographic, clinical, laboratory, hemodynamic, and echocardiographic variables.

Outcomes

The primary outcome was change in estimated glomerular filtration rate (eGFR) at 1 month after implantation. Secondary outcomes included eGFR changes at 3, 6, and 12 months.

Analytic Approach

Univariable and multivariable linear regression.

Results

Among 131 patients, average age was 60 ± 13 years, 83% were men, 47% had pre-existing chronic kidney disease, and mean preimplantation eGFR was 57 ± 23 mL/min/1.73 m². At 1-month following LVAD implantation, eGFR improved in 98 (75%) patients. Variables associated with 1-month increases in eGFR were younger age, absence of diabetes mellitus (DM), use of inotropes, lower implantation eGFR, and higher implantation serum urea nitrogen, alanine aminotransferase, bilirubin, and creatinine levels. In multivariable models, younger age (β = 7.14 mL/min/1.73 m² per SD; 95% CI, 3.17-11.10), lower eGFR (β = 7.72 mL/min/1.73 m² per SD; 95% CI, 3.10-12.34), and absence of DM (β = 10.36 mL/min/1.73 m²; 95% CI, 2.99-17.74) were each independently associated with 1-month improvement in eGFR. Only younger age and lower eGFR were associated with improvements in eGFR at later months.

Limitations

Single-center study. Loss to follow-up from heart transplantation and death over duration of study.

Conclusions

Only younger age, lower eGFR, and absence of DM were associated with improvement in eGFR at 1 month. Thus, prediction of eGFR change at 1 month and beyond is limited by using preimplantation variables.

Chlorogenic acid abates oxido-inflammatory and apoptotic responses in the liver and kidney of Tamoxifen-treated rats

Plant-derived phenolics are utilized as chemopreventive agents to abate adverse toxic responses associated with drug-induced damages. Tamoxifen (TAM)-a chemotherapeutic agent-is used in managing all stages of hormone-dependent breast cancer. Notwithstanding TAM's clinical side effect-including hepatic toxicity-its use is commonplace. The present study investigates the effect of Chlorogenic acid (CGA: 25 and 50 mg kg-1; per os (p.o)) reported to exhibit various beneficial properties, including antioxidative effect against TAM (50 mg/kg; p.o.)-induced hepatorenal toxicities in rats treated as follows: Control, CGA, or TAM alone, and rats co-treated with CGA and TAM for 2 weeks. Biomarkers of hepatorenal function, oxido-inflammatory stress, and hepatorenal histopathology were performed. We observed that TAM alone decreased relative organ weights (ROW), marginally impacted rat's survivability, and significantly (P < 0.05) increased hepatorenal toxicities and reactive oxygen and nitrogen species (RONS). TAM decreased (P < 0.05) antioxidant, anti-inflammatory cytokine (IL-10), besides increase in (P < 0.05) lipid peroxidation (LPO), pro-inflammatory cytokines (IL-1β, TNF-α), nitric oxide (NO), xanthine oxidase (XO), myeloperoxidase (MPO), and apoptotic caspases (Casp-3 and -9) levels. These biochemical alterations were accompanied by morphological lesions in experimental rats' liver and kidney. Conversely, that CGA dose-dependently relieved TAM-mediated toxic responses, restored antioxidants capacities, reduced oxidative stress, pro-inflammatory cytokines levels, and Casp-3 and -9 activities in experimental rats. Furthermore, CGA protected against lesions observed in the liver and kidney of rats treated with TAM alone. Overall, CGA blocked TAM-mediated hepatorenal injuries associated with pro-oxidative, inflammatory, and apoptotic mechanisms. CGA may serve as a chemoprotective agent boosting patients prognosis undergoing TAM chemotherapy.

Effects of Sodium-Glucose Co-transporter 2 Inhibition with Empaglifozin on Renal Structure and Function in Non-diabetic Rats with Left Ventricular Dysfunction After Myocardial Infarction

Background

The use of sodium–glucose co-transporter 2 inhibitors (SGLT2i) is currently expanding to cardiovascular risk reduction in non-diabetic subjects, but renal (side-)effects are less well studied in this setting.

Methods

Male non-diabetic Sprague Dawley rats underwent permanent coronary artery ligation to induce MI, or sham surgery. Rats received chow containing empagliflozin (EMPA) (30 mg/kg/day) or control chow. Renal function and electrolyte balance were measured in metabolic cages. Histological and molecular markers of kidney injury, parameters of phosphate homeostasis and bone resorption were also assessed.

Results

EMPA resulted in a twofold increase in diuresis, without evidence for plasma volume contraction or impediments in renal function in both sham and MI animals. EMPA increased plasma magnesium levels, while the levels of glucose and other major electrolytes were comparable among the groups. Urinary protein excretion was similar in all treatment groups and no histomorphological alterations were identified in the kidney. Accordingly, molecular markers for cellular injury, fibrosis, inflammation and oxidative stress in renal tissue were comparable between groups. EMPA resulted in a slight increase in circulating phosphate and PTH levels without activating FGF23–Klotho axis in the kidney and bone mineral resorption, measured with CTX-1, was not increased.

Conclusions

EMPA exerts profound diuretic effects without compromising renal structure and function or causing significant electrolyte imbalance in a non-diabetic setting. The slight increase in circulating phosphate and PTH after EMPA treatment was not associated with evidence for increased bone mineral resorption suggesting that EMPA does not affect bone health.

Electronic supplementary material

The online version of this article (10.1007/s10557-020-06954-6) contains supplementary material, which is available to authorized users.

Serum Creatinine as a Potential Biomarker for the Diagnosis of Tuberculous Pleural Effusion

BACKGROUND

Previous studies have revealed the disadvantages of traditional methods for the diagnosis of tuberculous pleural effusions (TPEs) and have created interest in exploring other effective biomarkers. Many studies have focused on the correlation between pulmonary diseases and serum creatinine (Cr), a representative biomarker of renal function, but little is known about the direct relationship between Cr and TPE. Our study aimed to explore whether Cr can act as a biomarker for the diagnosis of TPE and to evaluate the correlation between Cr and TPE.

MATERIALS AND METHODS

Patients with pleural effusions (PEs) were enrolled in this study. By comparing the concentrations of Cr and adenosine deaminase (ADA) in patients with TPEs and non-TPEs, we determined the sensitivity, specificity, Youden index, and area under the curve for these biomarkers. We generated receiver operating characteristic curves and quantifications to evaluate the diagnostic accuracy.

RESULTS

In total, 86 patients (44 with TPE, 25 with malignant pleural effusion (MPE) and 17 with non-tuberculosis infectious PE (NTIPE)) were enrolled in the study. The concentrations of Cr in TPE were significantly higher than those in non-TPE. However, a similar trend was not observed for NTIPE and MPE. The levels of ADA in TPE were significantly higher than those in NTIPE and MPE.

CONCLUSION

Cr has the potential for the diagnosis of TPE to some extent though its accuracy is not as good as that of ADA. Further studies are necessary for Cr to be applied in clinical practice for the diagnosis of TPE.

Clinical importance of urinary sodium excretion in acute heart failure

Aims

Urinary sodium assessment has recently been proposed as a target for loop diuretic therapy in acute heart failure (AHF). We aimed to investigate the time course, clinical correlates and prognostic importance of urinary sodium excretion in AHF.

Methods and results

In a prospective cohort of 175 consecutive patients with an admission for AHF we evaluated urinary sodium excretion 6 h after initiation of loop diuretic therapy. Clinical outcome was all‐cause mortality or heart failure rehospitalization. Mean age was 71 ± 14 years, and 44% were female. Median urinary sodium excretion was 130 (67–229) mmol at 6 h, 347 (211–526) mmol at 24 h, and decreased from day 2 to day 4. Lower urinary sodium excretion was independently associated with male gender, younger age, renal dysfunction and pre‐admission loop diuretic use. There was a strong association between urinary sodium excretion at 6 h and 24 h urine volume (beta = 0.702, P < 0.001). Urinary sodium excretion after 6 h was a strong predictor of all‐cause mortality after a median follow‐up of 257 days (hazard ratio 3.81, 95% confidence interval 1.92–7.57; P < 0.001 for the lowest vs. the highest tertile of urinary sodium excretion) independent of established risk factors and urinary volume. Urinary sodium excretion was not associated with heart failure rehospitalization.

Conclusion

In a modern, unselected, contemporary AHF population, low urinary sodium excretion during the first 6 h after initiation of loop diuretic therapy is associated with lower urine output in the first day and independently associated with all‐cause mortality.

Intravascular Volume Modulates the Outcome Predictive Capacity of Clinical Renal Function Biomarkers in Clinically "Euvolemic" Chronic Heart Failure Patients

BACKGROUND

Cardiorenal interconnections are complex and may in part be mediated by the extent of intravascular volume expansion. The impact of subclinical volume excess on outcomes in heart failure (HF) patients with chronic kidney disease (CKD) has not been examined previously.

OBJECTIVES

To assess the impact of volume-kidney interactions on outcomes in clinically "euvolemic" chronic HF patients (NYHA class II) with coexisting CKD.

METHODS

Plasma volume (PV) was prospectively measured in 110 stable HF patients with different degrees of renal function using a standardized radiolabeled albumin indicator-dilution technique. To examine the interactive roles of volume expansion and biomarkers of CKD, the cohort was dichotomized by median PV and then further stratified by cohort median serum creatinine, eGFR, and BUN, and analyzed for outcomes of HF-related mortality and 1st hospitalization.

RESULTS

PV was expanded above normal in 76% of the cohort. Over 1.5 years of follow-up, sCr and BUN above and eGFR below cohort median stratified higher risks for the composite endpoint only in ambulatory HF patients with a severe degree of PV expansion (median PV expansion ≥+26%; p = 0.02). With less expansion (<+26% expansion), these biomarkers reflecting worse renal function did not discriminate risk (p = 0.578). The percentage of subjects experiencing composite outcome events was, however, comparable for both greater and lesser degrees of PV expansion in HF patients with stable clinical status.

CONCLUSIONS

In clinically stable chronic HF patients with coexisting CKD, substantial subclinical PV expansion is common even when patients are considered clinically to be euvolemic, and, importantly, the extent of PV expansion impacts outcomes including early HF mortality. Better kidney function appears to mitigate the effects of excess PV expansion, while less volume expansion appears to limit the risk of worse renal function as reflected by clinical biomarkers of renal function. Thus, the extent of volume expansion impacts the capacity of standard clinical biomarkers of CKD to differentiate outcome risk in ambulatory chronic (NYHA class II) HF patients.

B-type natriuretic peptide trend predicts clinical significance of worsening renal function in acute heart failure

AIMS

In acute heart failure (AHF), relationships between changes in B-type natriuretic peptide (BNP) and worsening renal function (WRF) and its prognostic implications have not been fully determined. We investigated the relationship between WRF and a decrease in BNP with in-hospital and 1-year mortality in AHF.

METHODS AND RESULTS

The Acute Kidney Injury NGAL Evaluation of Symptomatic heart faIlure Study (AKINESIS) was a prospective, international, multicentre study of AHF patients. Severe WRF (sWRF) was a sustained increase of ≥44.2 μmol/L (0.5 mg/dL) or ≥50% in creatinine, non-severe WRF (nsWRF) was a non-sustained increase of ≥26.5 μmol/L (0.3 mg/dL) or ≥50% in creatinine, and WRF with clinical deterioration was nsWRF with renal replacement therapy, inotrope use, or mechanical ventilation. Decreased BNP was defined as a ≥30% reduction in the last measured BNP compared to admission BNP. Among 814 patients, the incidence of WRF was not different between patients with or without decreased BNP (nsWRF: 33% vs. 31%, P = 0.549; sWRF: 11% vs. 9%, P = 0.551; WRF with clinical deterioration: 8% vs. 10%, P = 0.425). Decreased BNP was associated with better in-hospital and 1-year mortality regardless of WRF, while WRF was associated with worse outcomes only in patients without decreased BNP. In multivariate Cox regression analysis, decreased BNP, sWRF, and WRF with clinical deterioration were significantly associated with 1-year mortality.

CONCLUSIONS

Decreased BNP was associated with better in-hospital and long-term outcomes. WRF was only associated with adverse outcomes in patients without decreased BNP.

Interleukin-34 Levels Were Associated with Prognosis in Patients with Acute Myocardial Infarction

Inflammatory factors have specific value in acute myocardial infarction (AMI). Our previous studies have identified the prognostic value of interleukin (IL)-34 during chronic heart failure. However, the potential impact of IL-34 on AMI remains unknown.Serum IL-34 was measured in 287 AMI patients, and they were followed up for the composite endpoint, including cardiovascular death, heart failure hospitalization, recurrent nonfatal myocardial infarction (MI), and nonfatal stroke.IL-34 levels were significantly associated with the presence of heart failure at baseline and its aggravation after a year. During the five-year follow-up, there was a significant increase in the risk of the composite endpoint (hazard ratio [HR] 1.38 [95% confidence intervals (CI) 1.12-1.70], P < 0.01) and cardiovascular death (HR 1.48 [95%CI 1.03-2.27], P = 0.03) after full adjustment as IL-34 levels increased.Higher IL-34 levels in the acute phase were associated with an increased risk of heart failure after MI and poor prognosis.

The endless story of markers of renal function and cardiovascular risk

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Implication of Acute Kidney Injury in Heart Failure

Patients with acute or chronic decompensated heart failure (ADHF) present with various degrees of heart and kidney dysfunction characterizing cardiorenal syndrome (CRS). CRS can be generally defined as a pathophysiologic disorder of the heart and kidneys whereby acute or chronic dysfunction of 1 organ may induce acute or chronic dysfunction of the other. ADHF is a challenge in the management of heart failure. This review provides an overview the pathophysiology of type 1 CRS together with new approaches to treatment in patients with heart failure with worsening renal function or acute kidney disease.

Conus striatus venom exhibits non-hepatotoxic and non-nephrotoxic potent analgesic activity in mice

Constant research into the pharmaceutical properties of marine natural products has led to the discovery of many potentially active agents considered worthy of medical applications. Genus Conus, which approximately comprises 700 species, is currently under every researcher's interest because of the conopeptides in their crude venom. Conopeptides have a wide range of pharmacological classes and properties. This research focused on the crude venom of Conus striatus to assess its analgesic activity, mutagenicity, nephrotoxicity, and hepatotoxicity in mice. The crude venom was extracted from the conus snails and the protein concentration was determined using Bradford's method. The analgesic activity of the venom was determined using the hot-plate method and standard IFCC method was used to determine the alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Evaluation of mutagenicity was done using micronucleus assay and the nephrotoxicity of the venom was determined using Kidney Coefficient and serum creatinine concentration. The maximum tolerable dose (MTD) of the crude venom was found to be 75 ppm. The venom exhibited potent analgesic activity even higher than the positive control (Ibuprofen). Most of the analgesic drugs can usually impact damage in the liver and kidneys. However, AST and ALT results revealed that the venom has no adverse effects on the liver. Although the venom increased the incidence of micronucleated polychromatic erythrocytes, making it mutagenic, with MTD concentration's mutagenicity comparable to the positive control methyl methanesulfonate (MMS). The kidney coefficients, on the other hand, showed no significant difference between the treated groups and that of the untreated group. The serum creatinine also showed a concentration-dependent increase; with MTD treated mice got the highest creatinine concentration. However, MTD/2 and MTD/4 showed no significant difference in creatinine levels with respect to the untreated groups. Hence, the nephrotoxicity of the venom was only evident when used at higher concentration. The venom exhibited potent analgesic activity indicated that the C. striatus crude venom extract could have a potential therapeutic component as analgesic drugs that displayed no hepatic damage. This study also suggests that for this venom to be utilized for future medical applications, their usage must be regulated and properly monitored to avoid nephrotoxic effect.

Passive sweat collection and colorimetric analysis of biomarkers relevant to kidney disorders using a soft microfluidic system

The rich range of biomarkers in sweat and the ability to collect sweat in a non-invasive manner create interest in the use of this biofluid for assessments of health and physiological status, with potential applications that range from sports and fitness to clinical medicine. This paper introduces two important advances in recently reported classes of soft, skin-interfaced microfluidic systems for sweat capture and analysis: (1) a simple, broadly applicable means for collection of sweat that bypasses requirements for physical/mental exertion or pharmacological stimulation and (2) a set of enzymatic chemistries and colorimetric readout approaches for determining the concentrations of creatinine and urea in sweat, throughout ranges that are physiologically relevant. The results allow for routine, non-pharmacological capture of sweat for patient populations, such as infants and the elderly, that cannot be expected to sweat through exercise, and they create potential opportunities in the use of sweat for kidney disease screening/monitoring. Studies on human subjects demonstrate these essential capabilities, with quantitative comparisons to standard methods. The results expand the range of options available in microfluidic sampling and sensing of sweat for disease diagnostics and health monitoring.

[Not Available]

Actuality. Impaired kidney function adversely influences both immediate and remote prognosis for patients with chronic heart failure (CHF). However, early detection and prediction of acute kidney injury (AKI) are understudied.The aim of study was to investigate hypoxia-inducible factor 1 (HIF-1) as a biomarker for early diagnosis of AKI and determining prognosis in patients with acute decompensated CHF (ADCHF).

MATERIALS AND METHODS

84 patients admitted for ADCHF (18 women; mean age, 61.4±7.1) were evaluated. ADCHF was diagnosed in accordance with SEHF guidelines for diagnosis and treatment of chronic heart failure (RCS, 2016). AKI was diagnosed according to KDIGO criteria (2012). HIF-1, N-terminal pro B-type natriuretic peptide (NТ-proBNP), and erythropoietin were measured in blood serum. The follow-up period lasted for 12 months.

RESULTS

AKI was diagnosed in 27 (32.1 %) patients. Level of HIF-1 was 1.27±0.63 ng / ml; NТ-proBNP - 2469.6 (interquartile range (IQR), 1312.2; 3300.0) pg / ml; eryhthropoietin - 56.0 mIU / ml (IQR, 13.2; 68.1). No correlation was found between HIF-1 and glomerular filtration rate, NТ-proBNP, or erythropoietin. Differences in biomarker levels were not observed between patients with and without AKI; however, HIF-1 was higher in the group of deceased patients than in the group of survived patients (1.64±0.9 vs. 1.17±0.44 ng / ml, р=0.004), which was not observed for NТ-proBNP and erythropoietin.

CONCLUSION

AKI was observed in every third patient with ADCHF. In ADCHF, HIF-1 was not correlated with the kidney function; however, a relationship was found between the HIF-1 level and prediction for patients with CHF.

Relation of Serum and Urine Renal Biomarkers to Cardiovascular Risk in Patients with Type 2 Diabetes Mellitus and Recent Acute Coronary Syndromes (From the EXAMINE Trial)

A deeper understanding of the interplay between the renal axis and cardiovascular (CV) disease is needed in type 2 diabetes mellitus (T2DM). We aimed to explore the prognostic value of a comprehensive panel of renal biomarkers in patients with T2DM at high CV risk. We evaluated the prognostic performance of both serum (Cystatin C) and urine renal biomarkers (neutrophil gelatinase-associated lipocalin, kidney injury molecule-1 protein, and indices of urinary protein excretion) in 5,380 patients with T2DM and recent acute coronary syndromes in the EXAMINE trial. Patients requiring dialysis within 14 days were excluded. Single- and multimarker covariate-adjusted Cox proportional hazards models were developed to predict times to events. Primary endpoint was composite nonfatal myocardial infarction, nonfatal stroke, or CV death. Median age was 61 years, 68% were men, and mean baseline estimated glomerular filtration rate (eGFR) was 74 mL/min/1.73 m². During median follow-up of 18 months, 621 (11.5%) experienced the primary endpoint and 326 (6.1%) patients had died. All renal biomarkers were robustly associated with adverse CV events in step-wise fashion, independent of baseline eGFR. However, in the multimarker prediction model, only Cystatin C (per 1 SD) was associated with the primary endpoint (hazard ratio [HR] 1.28 [1.14 to 1.45]; p ≤ 0.001), death (HR 1.51 [1.30 to 1.74]; p ≤ 0.001), and heart failure hospitalization (HR 1.20 [0.96 to 1.49]; p = 0.11). Association between Cystatin C and the primary endpoint was similar in baseline eGFR above and below 60 mL/min/1.73 m² (P_interaction > 0.05). In conclusion, serum and urine renal biomarkers, when tested alone, independently predict long-term adverse CV events in high-risk patients with T2DM. In an integrative panel of renal biomarkers, only serum Cystatin C remained independently associated with subsequent CV risk. Renal biomarkers informing various aspects of kidney function may further our understanding of the complex interplay between diabetic kidney disease and CV disease.

Redefining biomarkers in heart failure

Heart failure (HF) is the end result of many different cardiac and non-cardiac abnormalities leading to a complex clinical entity. In this view, the use of biomarkers in HF should be deeply reconsidered; indeed, the same biomarker may carry a different significance in patients with preserved or reduced EF. The aim of this review is to reconsider the role of biomarkers in HF, based on the different clinical characteristics of this syndrome. The role of cardiac and non-cardiac biomarkers will be reviewed with respect of the different clinical manifestations of this syndrome.

PROGNOSTIC VALUE OF KIDNEY FUNCTION PARAMETERS IN PATIENTS WITH CHRONIC HEART FAILURE AND LEFT VENTRICULAR REDUCED EJECTION FRACTION

Chronic heart failure (CHF) is a complex clinical syndrome characterized by progressive course, unsatisfactory quality of life, poor prognosis and high incidence of concomitant renal dysfunction (RD). The aim of our work was to study the prognostic value of a number of renal function indicators in patients with CHF and a reduced left ventricular ejection fraction (LVEF). Materials and methods. 134 patients with stable CHF and reduced (<40 %) LVEF, II-IVNYHA class were examined. Patients were divided into two groups according to the level of GFR: the first group of GFR<60 ml/min./1.73 m², the second – GFR≥60 ml/min./1.73 m². The average follow-up period was 13.4 months, the maximum was 27.5 months. Results. In 53 patients RD was detected (glomerular filtration rate was ˂60 ml/min/1.73 m²), which was 39.5 %. Patients of both groups did not differ in their main hemodynamic parameters, left ventricular ejection fraction, and pharmacotherapy structure, but were older in age and heavier clinically. After the analysis of survival curves of patients depending on GFR, a group of patients with RD had a significantly worse survival prognosis compared to a group without RD. After adjusting the groups by age and NYHA class, the indicated difference was maintained. The subjects were divided according to median levels: blood urea nitrogen, blood urea nitrogen / creatinine ratio, microalbuminuria, albumin / creatinine ratio in urine. The long-term survival of the formed groups was analyzed. The level of blood urea nitrogen did not significantly influence the prognosis of patients with CHF and reduced LVEF. At the same time, when the groups were divided, depending on the median value of the blood urea nitrogen / creatinine ratio, there was a significantly higher risk of fatal outcome in the group with lower indices. The level of MAU did not significantly affect the survival of patients. In addition, a comparison of the survival of patients with higher and lower values of the albumin / creatinine ratio in the urine revealed a significantly higher risk of death in patients with higher values. Conclusions: 1. The presence of RD (GFR˂60 ml/min/1.73 m²) is observed in 39.5 % of patients with CHF and reduced LVEF and is associated with their worst long-term survival. 2. The BUN and MAU do not have sufficient predictive information about the forecast of long-term survival of the above category of patients. 3. At the same time, the values of the BUN/ Сreatinine ratio ˂24.5 and the ACR ˃12.7 indicate patients with CHF who have a higher long-term risk of death.