Cardiovascular Disease in Chronic Kidney Disease: Pathophysiological Insights and Therapeutic Options

Inflammation in Children with CKD Linked to Gut Dysbiosis and Metabolite Imbalance

BACKGROUND

CKD is characterized by a sustained proinflammatory response of the immune system, promoting hypertension and cardiovascular disease. The underlying mechanisms are incompletely understood but may be linked to gut dysbiosis. Dysbiosis has been described in adults with CKD; however, comorbidities limit CKD-specific conclusions.

METHODS

We analyzed the fecal microbiome, metabolites, and immune phenotypes in 48 children (with normal kidney function, CKD stage G3-G4, G5 treated by hemodialysis [HD], or kidney transplantation) with a mean±SD age of 10.6±3.8 years.

RESULTS

Serum TNF-α and sCD14 were stage-dependently elevated, indicating inflammation, gut barrier dysfunction, and endotoxemia. We observed compositional and functional alterations of the microbiome, including diminished production of short-chain fatty acids. Plasma metabolite analysis revealed a stage-dependent increase of tryptophan metabolites of bacterial origin. Serum from patients on HD activated the aryl hydrocarbon receptor and stimulated TNF-α production in monocytes, corresponding to a proinflammatory shift from classic to nonclassic and intermediate monocytes. Unsupervised analysis of T cells revealed a loss of mucosa-associated invariant T (MAIT) cells and regulatory T cell subtypes in patients on HD.

CONCLUSIONS

Gut barrier dysfunction and microbial metabolite imbalance apparently mediate the proinflammatory immune phenotype, thereby driving the susceptibility to cardiovascular disease. The data highlight the importance of the microbiota-immune axis in CKD, irrespective of confounding comorbidities.

Is Adynamic Bone Always a Disease? Lessons from Patients with Chronic Kidney Disease

Renal osteodystrophy (ROD) is a common complication of end-stage kidney disease that often starts early with loss of kidney function, and it is considered an integral part in management of patients with chronic kidney disease (CKD). Adynamic bone (ADB) is characterized by suppressed bone formation, low cellularity, and thin osteoid seams. There is accumulating evidence supporting increasing prevalence of ADB, particularly in early CKD. Contemporarily, it is not very clear whether it represents a true disease, an adaptive mechanism to prevent bone resorption, or just a transitional stage. Several co-players are incriminated in its pathogenesis, such as age, diabetes mellitus, malnutrition, uremic milieu, and iatrogenic factors. In the present review, we will discuss the up-to-date knowledge of the ADB and focus on its impact on bone health, fracture risk, vascular calcification, and long-term survival. Moreover, we will emphasize the proper preventive and management strategies of ADB that are pivotal issues in managing patients with CKD. It is still unclear whether ADB is always a pathologic condition or whether it can represent an adaptive process to suppress bone resorption and further bone loss. In this article, we tried to discuss this hard topic based on the available limited information in patients with CKD. More studies are needed to be able to clearly address this frequent ROD finding.

Long-Term Evaluation of Changes in Kidney Function after Switching from Tenofovir Disoproxil Fumarate to Tenofovir Alafenamide in Patients Living with HIV

Tenofovir is one of the most widely used medications for HIV treatment and is administered as either tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF). Use of TAF is preferred as it is associated with fewer negative impacts on renal function; however, long-term follow-up beyond 96 weeks is limited. A retrospective chart review of patients ≥18 years who received TDF-containing anti-retroviral therapy (ART) for ≥6 months and then switched to a TAF-containing regimen between 1 December 2015 and 1 January 2020 is presented. The primary objective was to evaluate changes in kidney function as measured by eGFR and Scr. The secondary objective was to evaluate changes in lipids. Among the 142 patients identified, the median age was 66 years old with a median follow-up of 3.6 years. The change in kidney function was a median increase in Scr of 0.1 mg/dL and a decrease in eGFR of -8 mL/min/1.73 m². The change in lipid panels at the end of the medication use evaluation endpoint was a decrease in total cholesterol, LDL, HDL, and triglycerides of -2.5, -0.1, -0.6, and -9 mmol/L, respectively. There was no clinically meaningful difference in kidney function as measured by eGFR or Scr, nor was there any clinically meaningful difference in lipid panels in patients switched from TDF to TAF-containing ART. Our observations suggest that the favorable impact of TAF on kidney function is sustained for at least 44 months after conversion from TDF.

MCP1 Could Mediate FGF23 and Omega 6/Omega 3 Correlation Inversion in CKD

Fibroblast growth factor 23 (FGF23) concentrations rise after the early stages of chronic kidney disease (CKD). FGF23 is involved in inflammatory reactions closely associated with an incremented risk of cardiovascular disease (CVD). There is growing evidence that omega-6 (n-6) and n-3 polyunsaturated fatty acids (PUFA) can modulate inflammation through several mediators producing an opposite effect on cardiovascular (CV) risks. In this study, we explore whether there is any correlation between PUFA, FGF23, and inflammation in CKD patients. We evaluated, cross-sectionally, 56 patients at different stages of CKD. Monocyte chemoattractant protein 1 (MCP1), and intact and c-terminal FGF23 (iFGF23, cFGF23) were quantified by the ELISA, and the fatty acids (FA) profile was analyzed by gas chromatography. Concurrently with an eGFR decrease (p < 0.01) and an MCP1 increase (p = 0.031), we observed an inversion of the correlation between FGF23 and the n-6/n-3 ratio. This last correlation was inversed in CKD stage 3 (r2 (−) 0.502 p = 0.029) and direct in stage 5 (r2 0.657 p = 0.020). The increase in MCP1 seems to trigger events in the inversion of the correlation between FGF23 and the n-6/n-3 PUFA ratio. This result strongly encourages future studies on basal pathways, on possible pharmacological interventions, and on managing kidney transplant patients treated with immunosuppressive therapy.

Assessment of Health-Related Quality of Life, Medication Adherence, and Prevalence of Depression in Kidney Failure Patients

BACKGROUND

Kidney failure is a global health problem with a worldwide mean prevalence rate of 13.4%. Kidney failure remains symptomless during most of the early stages until symptoms appear in the advanced stages. Kidney failure is associated with a decrease in health-related quality of life (HRQOL), deterioration in physical and mental health, and an increased risk of cardiovascular morbidity and mortality. This study aimed to evaluate the factors associated with decreased HRQOL and other factors affecting the overall health of patients. Another objective was to measure how medication adherence and depression could affect the overall HRQOL in patients with kidney failure.

METHODOLOGY

The study used a prospective follow-up mix methodology approach with six-month follow-ups of patients. The participants included in the study population were those with chronic kidney disease grade 4 and kidney failure. Pre-validated and translated questionnaires (Kidney Disease Quality of Life-Short Form, Hamilton Depression Rating Scale Urdu Version, and Morisky Lewis Greens Adherence Scale) and assessment tools were used to collect data.

RESULTS

This study recruited 314 patients after an initial assessment based on inclusion criteria. The mean age of the study population was 54.64 ± 15.33 years. There was a 47.6% male and a 52.4% female population. Hypertension and diabetes mellitus remained the most predominant comorbid condition, affecting 64.2% and 74.6% of the population, respectively. The study suggested a significant (p < 0.05) deterioration in the mental health composite score with worsening laboratory variables, particularly hematological and iron studies. Demographic variables significantly impact medication adherence. HRQOL was found to be deteriorating with a significant impact on mental health compared to physical health.

CONCLUSIONS

Patients on maintenance dialysis for kidney failure have a significant burden of physical and mental symptoms, depression, and low HRQOL. Given the substantial and well-known declines in physical and psychological well-being among kidney failure patients receiving hemodialysis, the findings of this research imply that these areas related to health should receive special attention in the growing and expanding population of kidney failure patients.

Interleukin-6 and Outcome of Chronic Hemodialysis Patients with SARS-CoV-2 Pneumonia

Background and Objectives: Chronic hemodialysis (CHD) patients are at increased risk of SARS-CoV-2 infection and the related complications and mortality of COVID-19 due to the high rate of comorbidities combined with advanced age. This observational study investigated the clinical manifestations of SARS-CoV-2 infection in CHD and the risk factors for patients′ death. Materials and Methods: The study included 26 CHD patients with SARS-CoV-2 pneumonia detected by positive RT-PCR on nasopharyngeal swabs and high-resolution computed tomography at hospital admission, aged 71 + 5.9 years, 14 of which (53.8%) were male, 20 (77%) under hemodiafiltration, and 6 (23%) on standard hemodialysis, with a median follow-up of 30 days. Results: Simple logistic regression analysis revealed that the factors associated with a higher risk of death were older age (OR: 1.133; 95%CI: 1.028−1.326, p = 0.0057), IL-6 levels at admission (OR: 1.014; 95%CI: 1.004−1.028, p = 0.0053), and C-reactive protein (OR: 1.424; 95%CI: 1.158−2.044, p < 0.0001). In the multiple logistic regression model, circulating IL-6 values at admission remained the only significant prognosticator of death. The ROC curve indicated the discriminatory cut-off value of 38.20 pg/mL of blood IL-6 for predicting death in chronic hemodialysis patients with SARS-CoV-2 pneumonia (sensitivity: 100%; specificity: 78%; AUC: 0.8750; p = 0.0027). Conclusions: This study identified a threshold of IL-6 levels at hospital admission for death risk in CHD patients with SARS-CoV-2 pneumonia. This might represent a valuable outcome predictor, feasibly better than other clinical, radiological, or laboratory parameters and preceding the IL-6 peak, which is unpredictable.

Serum Biomarkers of Renal Fibrosis: A Systematic Review

Chronic kidney disease (CKD) is a widely diffuse pathological condition which deeply impacts upon an affected patient's quality of life and its worldwide rate is predicted to further rise. The main biological mechanism underlying CKD is renal fibrosis, a non-reversible process representing, for the affected system, a point of no return of tissue damage and dysfunction, deeply reducing the possible therapeutic strategies at the disposal of physicians. The best tool clinicians can use to address the extent of renal fibrosis at any level (glomeruli, tubule-interstitium, vasculature) is kidney biopsy that, despite its overall safety, remains an invasive procedure showing some shortcomings. Thus, the identification of novel non-invasive renal fibrosis biomarkers would be of fundamental importance. Here, when systematically reviewing the available evidence on serological biomarkers associated with renal fibrosis evaluated in patients suffering from CKD in the last five years, we found that despite the presence of several promising biomarkers, the level of observed evidence is still very scattered. Probably, the use of multiple measures capable of addressing different aspects involved in this condition would be the most suitable way to capture the high complexity characterizing the renal fibrotic process, having consequently a great impact on clinical practice by maximizing prevention, diagnosis, and management.

Personalised cooler dialysate for patients receiving maintenance haemodialysis (MyTEMP): a pragmatic, cluster-randomised trial

BACKGROUND

Haemodialysis centres have conventionally provided maintenance haemodialysis using a standard dialysate temperature (eg, 36·5°C) for all patients. Many centres now use cooler dialysate (eg, 36·0°C or lower) for potential cardiovascular benefits. We aimed to assess whether personalised cooler dialysate, implemented as centre-wide policy, reduced the risk of cardiovascular-related death or hospital admission compared with standard temperature dialysate.

METHODS

MyTEMP was a pragmatic, two-arm, parallel-group, registry-based, open-label, cluster-randomised, superiority trial done at haemodialysis centres in Ontario, Canada. Eligible centres provided maintenance haemodialysis to at least 15 patients a week, and the medical director of each centre had to confirm that their centre would deliver the assigned intervention. Using covariate-constrained randomisation, we allocated 84 centres (1:1) to use either personalised cooler dialysate (nurses set the dialysate temperature 0·5-0·9°C below each patient's measured pre-dialysis body temperature, with a lowest recommended dialysate temperature of 35·5°C), or standard temperature dialysate (36·5°C for all patients and treatments). Patients and health-care providers were not masked to the group assignment; however, the primary outcome was recorded in provincial databases by medical coders who were unaware of the trial or the centres' group assignment. The primary composite outcome was cardiovascular-related death or hospital admission with myocardial infarction, ischaemic stroke, or congestive heart failure during the 4-year trial period. Analysis was by intention to treat. The study is registered at ClinicalTrials.gov, NCT02628366.

FINDINGS

We assessed all of Ontario's 97 centres for inclusion into the study. Nine centres had less than 15 patients and one director requested that four of their seven centres not participate. 84 centres were recruited and on Feb 1, 2017, these centres were randomly assigned to administer personalised cooler dialysate (42 centres) or standard temperature dialysate (42 centres). The intervention period was from April 3, 2017, to March 31, 2021, and during this time the trial centres provided outpatient maintenance haemodialysis to 15 413 patients (about 4·3 million haemodialysis treatments). The mean dialysate temperature was 35·8°C in the cooler dialysate group and 36·4°C in the standard temperature group. The primary outcome occurred in 1711 (21·4%) of 8000 patients in the cooler dialysate group versus 1658 (22·4%) of 7413 patients in the standard temperature group (adjusted hazard ratio 1·00, 96% CI 0·89 to 1·11; p=0·93). The mean drop in intradialytic systolic blood pressure was 26·6 mm Hg in the cooler dialysate group and 27·1 mm Hg in the standard temperature group (mean difference -0·5 mm Hg, 99% CI -1·4 to 0·4; p=0·14).

INTERPRETATION

Centre-wide delivery of personalised cooler dialysate did not significantly reduce the risk of major cardiovascular events compared with standard temperature dialysate. The rising popularity of cooler dialysate is called into question by this study, and the risks and benefits of cooler dialysate in some patient populations should be clarified in future trials.

FUNDING

Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Renal Network, Ontario Strategy for Patient-Oriented Research Support Unit, Dialysis Clinic, Inc., ICES (formerly known as the Institute for Clinical Evaluative Sciences), Lawson Health Research Institute, and Western University.

Rate and Risk Factors of Acute Myocardial Infarction after Debut of Chronic Kidney Disease-Results from the KidDiCo

Chronic kidney disease (CKD) is a known risk factor for cardiovascular disease, including acute myocardial infarction. However, whether this risk is only associated with severe kidney disease or is also related to mildly impaired kidney function is still under debate. The incidence rate and risk factors of incident acute myocardial infarction (AMI) in patients with CKD are sparse. Potential differences in risk factor profiles between CKD patients with incident AMI and CKD patients with a prior AMI have not been sufficiently investigated. Furthermore, important factors such as albuminuria and socio-economic factors are often not included. The primary aim of this study was to establish the incidence rate of AMI after CKD debut. Secondly, to evaluate the importance of different CKD stages and the risk of having an AMI. Finally, to identify individuals at risk for AMI after CKD debut adjusted for prevalent AMI. Based on data from the kidney disease cohort of Southern Denmark (KidDiCo), including 66,486 CKD patients, we established incidence rates and characteristics of incident AMI among patients within a 5-year follow-up period after CKD debut. A Cox regression was performed to compute the cause-specific hazard ratios for the different risk factors. The incidence rate for CKD stage G3−5 patients suffering acute myocardial infarction is 2.5 cases/1000 people/year. In patients without a previous myocardial infarction, the risk of suffering a myocardial infarction after CKD debut was only significant in CKD stage G4 (HR = 1.402; (95% CI: 1.08−1.81); p-value = 0.010) and stage G5 (HR = 1.491; (95% CI: 1.01−2.19); p-value = 0.042). This was not the case in patients who had suffered an acute myocardial infarction prior to their CKD debut. In this group, a previous myocardial infarction was the most critical risk factor for an additional myocardial infarction after CKD debut (HR = 2.615; (95% CI: 2.241−3.05); p-value < 0.001). Irrespective of a previous myocardial infarction, age, male sex, hypertension, and a low educational level were significant risk factors associated with an acute myocardial infarction after CKD debut. The incidence rate of AMI in patients with CKD stage G3−5 was 2.5 cases/1000 people/year. Risk factors associated with incident AMI in CKD stage G3−5 patients were CKD stage, age, and hypertension. Female sex and higher educational levels were associated with a lower risk for AMI. Prior AMI was the most significant risk factor in patients with and without previous AMI before fulfilling CKD stage G3−5 criteria. Only age, sex, and a medium-long educational level were significant risk factors in this group.

Sarcopenia and cardiovascular disease in patients with and without kidney disease: what do we know?

Cardiovascular disease (CVD) incidence is high in patients with chronic kidney disease (CKD) and is the most frequent cause of mortality in this population. Advanced age, hypertension, uremic toxins, endothelial dysfunction, atherosclerosis, hyperhomocysteinemia, oxidative stress, and inflammation are among the leading causes of increased CVD in advanced stages of CKD. Although defined as a decrease in muscle strength associated with aging, sarcopenia is also prevalent in CKD patients. Sarcopenia causes physical disability, low quality of life, and mortality. Regular exercise and nutritional supplementation may slow the progression of sarcopenia. Recent studies have shown that sarcopenia increases the risk of CVD and mortality in people with or without kidney disease. This review discusses the relationship between sarcopenia and CVD in light of the current literature.

Management of Patients With Kidney Disease in Need of Cardiovascular Catheterization: A Scientific Workshop Cosponsored by the National Kidney Foundation and the Society for Cardiovascular Angiography and Interventions

Patients with chronic kidney disease (CKD) are at an increased risk of developing cardiovascular disease (CVD), whereas those with established CVD are at risk of incident or progressive CKD. Compared with individuals with normal or near normal kidney function, there are fewer data to guide the management of patients with CVD and CKD. As a joint effort between the National Kidney Foundation and the Society for Cardiovascular Angiography and Interventions, a workshop and subsequent review of the published literature was held. The present document summarizes the best practice recommendations of the working group and highlights areas for further investigation.

South Asian ethnicity: What can we do to make this risk enhancer a risk equivalent?

South Asians account for around 25% of the global population and are the fastest-growing ethnicity in the US. This population has an increasing burden of atherosclerotic cardiovascular disease (ASCVD) which is also seen in the diaspora. Current risk prediction equations underestimate this risk and consider the South Asian ethnicity as a risk-enhancer among those with borderline-intermediate risk. In this review, we discuss why the South Asian population is at a higher risk of ASCVD and strategies to mitigate this increased risk.

Uremic toxins in chronic kidney disease highlight a fundamental gap in understanding their detrimental effects on cardiac electrophysiology and arrhythmogenesis

Chronic kidney disease (CKD) and cardiovascular disease (CVD) have an estimated 700-800 and 523 million cases worldwide, respectively, with CVD being the leading cause of death in CKD patients. The pathophysiological interplay between the heart and kidneys is defined as the cardiorenal syndrome (CRS), in which worsening of kidney function is represented by increased plasma concentrations of uremic toxins (UTs), culminating in dialysis patients. As there is a high incidence of CVD in CKD patients, accompanied by arrhythmias and sudden cardiac death, knowledge on electrophysiological remodeling would be instrumental for understanding the CRS. While the interplay between both organs is clearly of importance in CRS, the involvement of UTs in pro-arrhythmic remodeling is only poorly investigated, especially regarding the mechanistic background. Currently, the clinical approach against potential arrhythmic events is mainly restricted to symptom treatment, stressing the need for fundamental research on UT in relation to electrophysiology. This review addresses the existing knowledge of UTs and cardiac electrophysiology, and the experimental research gap between fundamental research and clinical research of the CRS. Clinically, mainly absorbents like ibuprofen and AST-120 are studied, which show limited safe and efficient usability. Experimental research shows disturbances in cardiac electrical activation and conduction after inducing CKD or exposure to UTs, but are scarcely present or focus solely on already well-investigated UTs. Based on UTs data derived from CKD patient cohort studies, a clinically relevant overview of physiological and pathological UTs concentrations is created. Using this, future experimental research is stimulated to involve electrophysiologically translatable animals, such as rabbits, or in vitro engineered heart tissues.

The renal system and associated disorders

Disorders of the renal system, including the kidneys and urinary tract, are increasingly recognised as a public health concern, accounting for 830 000 deaths worldwide. Patients often have comorbidities, with many presenting with other diseases. Health professionals require good knowledge of the renal system and associated disorders to create holistic care plans to meet individual patients' needs. This article covers the pathophysiology of some of the most common problems, patient assessment and investigations, and considerations in helping patients with self-management.

Finerenone efficacy in patients with chronic kidney disease, type 2 diabetes and atherosclerotic cardiovascular disease

AIMS

Finerenone, a selective, non-steroidal mineralocorticoid receptor antagonist, improves cardiovascular (CV) and kidney outcomes in patients with type 2 diabetes (T2D) and chronic kidney disease (CKD). This subgroup analysis of FIDELITY, a pre-specified, pooled, individual patient-data analysis of FIDELIO-DKD (NCT02540993) and FIGARO-DKD (NCT02545049), compared finerenone vs. placebo in patients with and without baseline history of atherosclerotic CV disease (ASCVD).

METHODS AND RESULTS

Outcomes included a composite CV outcome [CV death, non-fatal myocardial infarction, non-fatal stroke, or hospitalization for heart failure (HHF)]; CV death or HHF; a composite kidney outcome (kidney failure, sustained estimated glomerular filtration rate decrease ≥57%, or kidney-related death); all-cause mortality; and safety by baseline history of ASCVD.Of 13 026 patients, 5935 (45.6%) had a history of ASCVD. The incidence of the composite CV outcome, CV death or HHF, and all-cause mortality was higher in patients with ASCVD vs. those without, with no difference between groups in the composite kidney outcome. Finerenone consistently reduced outcomes vs. placebo in patients with and without ASCVD (P-interaction for the composite CV outcome, CV death or HHF, the composite kidney outcome, and all-cause mortality 0.38, 0.68, 0.33, and 0.38, respectively). Investigator-reported treatment-emergent adverse events were consistent between treatment arms across ASCVD subgroups.

CONCLUSION

Finerenone reduced the risk of CV and kidney outcomes consistently across the spectrum of CKD in patients with T2D, irrespective of prevalent ASCVD.

Mineral Bone Disorders in Kidney Disease Patients: The Ever-Current Topic

Chronic kidney disease (CKD) is a complex and multifactorial disease, and one of the most prevalent worldwide. Chronic kidney disease-mineral bone disorders (CKD-MBD) with biochemical and hormonal alterations are part of the complications associated with the progression of CKD. Pathophysiology of CKD-MBD focused on abnormalities in serum levels of several biomarkers (such as FGF-23, klotho, phosphate, calcium, vitamin D, and PTH) which are discussed in this review. We therefore examine the prognostic association between CKD-MBD and the increased risk for cardiovascular events, mortality, and CKD progression to end-stage kidney disease (ESKD). Lastly, we present specific treatments acting on CKD to prevent and treat the complications associated with secondary hyperparathyroidism (SHPT): control of hyperphosphatemia (with dietary restriction, intestinal phosphate binders, and adequate dialysis), the use of calcimimetic agents, vitamin D, and analogues, and the use of bisphosphonates or denosumab in patients with osteoporosis.

Prognostic Impact of Coronary Flow Reserve in Patients With CKD

Introduction

Both coronary flow reserve (CFR) and chronic kidney disease (CKD) are known to be associated with adverse cardiac events. However, it is unclear how these prognostic factors are interrelated. This study evaluated the association between intracoronary physiologic indexes and CKD and their prognostic implications.

Methods

A total of 351 patients without left ventricular systolic dysfunction (ejection fraction ≥ 40%) and not on dialysis whose revascularization was deferred based on fractional flow reserve (FFR) > 0.80 were analyzed. Depressed CFR was defined as CFR ≤ 2.0. The primary outcome was a composite of cardiac death or hospitalization for heart failure at 3 years.

Results

Patients with CKD showed lower CFR than the non-CKD population (3.28 ± 1.77 vs. 2.60 ± 1.09, P < 0.001), mainly driven by increased resting coronary flow. There was no significant difference in hyperemic coronary flow, FFR, and index of microvascular resistance between the 2 groups. CFR was significantly associated with estimated glomerular filtration rate (eGFR) (P = 0.045), and the proportion of depressed CFR was significantly increased with higher CKD stages (P = 0.011). The risk of cardiac death or hospitalization for heart failure was the lowest in the non-CKD and preserved CFR group (11.9%) and the highest in the CKD and depressed CFR group (60.0%, overall log rank P < 0.001). Both CKD (adjusted hazard ratio [HR_adj] 2.614, 95% confidence interval [CI] 1.505-4.539, P < 0.001) and depressed CFR (HR_adj 3.237, 95% CI 2.015-5.199, P < 0.001) were independently associated with the risk of the primary outcome.

Conclusion

There was a significant association between severity of CKD and CFR. Both CKD and depressed CFR showed independent association with higher risk of cardiac death or hospitalization for heart failure.

Arteriovenous Fistulae in Chronic Kidney Disease and the Heart: Physiological, Histological, and Transcriptomic Characterization of a Novel Rat Model

Background Arteriovenous fistulae (AVFs) are the gold standard for vascular access in those requiring hemodialysis but may put an extra hemodynamic stress on the cardiovascular system. The complex interactions between the heart, kidney, and AVFs remain incompletely understood. Methods and Results We characterized a novel rat model of five-sixths partial nephrectomy (NX) and AVFs. NX induced increases in urea, creatinine, and hippuric acid. The addition of an AVF (AVF+NX) further increased urea and a number of uremic toxins such as trimethylamine N-oxide and led to increases in cardiac index, left and right ventricular volumes, and right ventricular mass. Plasma levels of uremic toxins correlated well with ventricular morphology and function. Heart transcriptomes identified altered expression of 8 genes following NX and 894 genes following AVF+NX, whereas 290 and 1431 genes were altered in the kidney transcriptomes, respectively. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed gene expression changes related to cell division and immune activation in both organs, suppression of ribosomes and transcriptional activity in the heart, and altered renin-angiotensin signaling as well as chronodisruption in the kidney. All except the latter were worsened in AVF+NX compared with NX. Conclusions Inflammation and organ dysfunction in chronic kidney disease are exacerbated following AVF creation. Furthermore, our study provides important information for the discovery of novel biomarkers and therapeutic targets in the management of cardiorenal syndrome.

Long-Term Excessive Dietary Phosphate Intake Increases Arterial Blood Pressure, Activates the Renin-Angiotensin-Aldosterone System, and Stimulates Sympathetic Tone in Mice

Increased dietary phosphate intake has been associated with severity of coronary artery disease, increased carotid intima–media thickness, left ventricular hypertrophy (LVH), and increased cardiovascular mortality and morbidity in individuals with normal renal function as well as in patients suffering from chronic kidney disease. However, the underlying mechanisms are still unclear. To further elucidate the cardiovascular sequelae of long-term elevated phosphate intake, we maintained male C57BL/6 mice on a calcium, phosphate, and lactose-enriched diet (CPD, 2% Ca, 1.25% P, 20% lactose) after weaning them for 14 months and compared them with age-matched male mice fed a normal mouse diet (ND, 1.0% Ca, 0.7% P). Notably, the CPD has a balanced calcium/phosphate ratio, allowing the effects of elevated dietary phosphate intake largely independent of changes in parathyroid hormone (PTH) to be investigated. In agreement with the rationale of this experiment, mice maintained on CPD for 14 months were characterized by unchanged serum PTH but showed elevated concentrations of circulating intact fibroblast growth factor-23 (FGF23) compared with mice on ND. Cardiovascular phenotyping did not provide evidence for LVH, as evidenced by unchanged LV chamber size, normal cardiomyocyte area, lack of fibrosis, and unchanged molecular markers of hypertrophy (Bnp) between the two groups. However, intra-arterial catheterization revealed increases in systolic pressure, mean arterial pressure, and pulse pressure in mice fed the CPD. Interestingly, chronically elevated dietary phosphate intake stimulated the renin–angiotensin–aldosterone system (RAAS) as evidenced by increased urinary aldosterone in animals fed the CPD, relative to the ND controls. Furthermore, the catecholamines epinephrine, norepinephrine, and dopamine as well as the catecholamine metabolites metanephrine. normetanephrine and methoxytyramine as measured by mass spectrometry were elevated in the urine of mice on CPD, relative to mice on the ND. These changes were partially reversed by switching 14-month-old mice on CPD back to ND for 2 weeks. In conclusion, our data suggest that excess dietary phosphate induces a rise in blood pressure independent of secondary hyperparathyroidism, and that this effect may be mediated through activation of the RAAS and stimulation of the sympathetic tone.

The Anti-inflammatory Effect of Chitosan Oligosaccharide on Heart Failure in Mice

Heart failure is currently one of the leading causes of death worldwide, and the inflammatory factors play an important role in its development. Chitosan oligosaccharide (COS), a low-molecular-weight form of chitosan, has many specific biological activities. In this study, COS effects on heart failure were studied for the first time by performing transverse arch constriction (TAC) surgery in mice, as an animal model of heart failure. Our findings revealed that COS administration (in both 40 mg/kg and 80 mg/kg doses) significantly ameliorated TCA-induced left ventricular (LV) hypertrophy as well as the increase in lung and heart weight in mice, while improving TAC-induced LV dysfunction. Both doses effectively attenuated LV cardiomyocyte hypertrophy, while decreasing heart inflammation after heart failure in mice. In conclusion, our results indicated that the supplementation of COS in normal diet might be an effective way to prevent further myocardial tissue damage in patients suffering from heart failure.

Incidence and Outcomes of Advanced Heart Failure in Adults With Congenital Heart Disease

BACKGROUND

There are limited data about the stage D heart failure (advanced HF) in adults with congenital heart disease. Our study objectives were (1) to determine the incidence of new-onset advanced HF in patients and the relationship between advanced HF and all-cause mortality and (2) to determine the relationship between therapies for advanced HF and all-cause mortality.

METHODS

Retrospective cohort study of adults with congenital heart disease at Mayo Clinic (2003-2019). We defined advanced HF using the European Society of Cardiology diagnostic criteria for advanced HF. Therapies received by the patients with advanced HF were classified into 3 mutually exclusive groups (treatment pathways): (1) conventional cardiac intervention, (2) transplant listing, and (3) palliative care.

RESULTS

Of 5309 patients without advanced HF at baseline assessment, 432 (8%) developed advanced HF during follow-up (1.1%/y), and the incidence of advanced HF was higher in patients with severe or complex congenital heart disease. Onset of advanced HF was associated with 6-fold increase in the risk of mortality. Conventional cardiac intervention was associated with significantly higher risk of mortality as compared to transplant listing. The longer the interval from the initial onset of advanced HF to transplant evaluation, the lower the odds of being listed for transplant.

CONCLUSIONS

Based on these data, we postulate that early identification of patients with advanced HF, and a timely referral for transplant evaluation (instead of conventional cardiac intervention) may offer the best chance of survival for these critically ill patients. Further studies are required to validate this postulation.

Cardiac micro-RNA and transcriptomic profile of a novel swine model of chronic kidney disease and left ventricular diastolic dysfunction

Chronic kidney disease (CKD) is an independent risk factor for the development of heart failure, but the underlying mechanisms remain unknown. Using a novel translational swine model of CKD and cardiac dysfunction, we hypothesize that CKD alters the cardiac miRNA and transcriptomic profile that associate with cardiac remodeling and metabolic processes implicated in the development of left ventricular diastolic dysfunction (CKD-LVDD). CKD-LVDD and normal control pigs (n = 6 each) were studied for 14 wk. Renal and cardiac hemodynamics were quantified by multidetector CT and echocardiography. In randomly selected pigs (n = 3/group), cardiac miRNA- and mRNA-sequencing (seq) was performed, validated (qPCR), and followed by confirmatory ex vivo studies. Differential expression analysis identified nine miRNAs and 125 mRNAs upregulated and 17 miRNAs and 172 mRNAs downregulated [fold-change ≥ 2, and false discovery rate (FDR) ≤ 0.05] in CKD-LVDD versus normal controls. Integrated miRNA-/mRNA-seq analysis identified 71 overlappings downregulated mRNA targets of miRNAs upregulated, and 39 overlappings upregulated mRNA targets of miRNAs downregulated in CKD-LVDD versus controls. Functional analysis showed that these genes were primarily implicated in processes associated with cardiac remodeling, including ubiquitination, ATP and fatty acid synthesis, and extracellular matrix remodeling. In agreement, hearts of CKD-LVDD pigs exhibited abnormal diastolic relaxation, mitochondrial injury, moderate LV fibrosis, and myocardial lipid accumulation. Our work comprehensively characterizes the cardiac micro-RNA and transcriptomic profile of a translational model of CKD-LVDD. Our data may set the foundation for new targeted studies to further elucidate LVDD pathophysiology and assist to develop therapeutic interventions.NEW & NOTEWORTHY Chronic kidney disease (CKD) is a progressive disorder in which more than 50% of deaths are attributed to cardiovascular disease. Using a swine model of CKD that develops left ventricular dysfunction (CKD-LVDD), we characterize the cardiac micro-RNA and transcriptomic profile, identifying dysregulated genes associated with cardiac remodeling and fatty acid metabolism that might be post-transcriptionally regulated early in the disease. These findings pinpointed pathological pathways that may open new avenues toward therapeutic research to reduce cardiovascular morbidity in CKD.

Statin uses in adults with non-dialysis advanced chronic kidney disease: Focus on clinical outcomes of infectious and cardiovascular diseases

Background: Statins are commonly used for cardiovascular disease (CVD) prevention. Observational studies reported the effects on sepsis prevention and mortality improvement. Patients with chronic kidney disease (CKD) are at high risk for CVD and infectious diseases. Limited information is available for statin use in patients with non-dialysis CKD stage V.

Method: The retrospective observational study included patients with non-dialysis CKD stage V, with either de novo statin use or none. Patients who were prior statin users and had prior cardiovascular events were excluded. The key outcomes were infection-related hospitalization, major adverse cardiovascular events (MACE) (non-fatal myocardial infarction, hospitalization for heart failure, or non-fatal stroke), and all-cause mortality. The data were retrieved from the Chang Gung Research Database (CGRD) from January 2001 to December 2019. Analyses were conducted with Cox proportional hazard regression models in the propensity score matching (PSM) cohort.

Result: A total of 20,352 patients with CKD stage V were included (1,431 patients were defined as de novo statin users). After PSM, 1,318 statin users were compared with 1,318 statin non-users. The infection-related hospitalization (IRH) rate was 79.3 versus 94.3 per 1,000 person-years in statin users and statin non-users, respectively [hazard ratio (HR) 0.83, 95% confidence interval (CI) 0.74–0.93, p = 0.002]. The incidence of MACE was 38.9 versus 55.9 per 1,000 person-years in statin users and non-users, respectively (HR, 0.72; 95% CI 0.62–0.83, p < 0.001). The all-cause mortality did not differ between statin users and non-users, but statin users had lower infection-related mortality than non-users (HR, 0.59; 95% CI 0.38–0.92, p = 0.019).

Conclusion:De novo use of statin in patients with non-dialysis CKD stage V reduced the incidence of cardiovascular events, hospitalization, and mortality for infectious disease. The study results reinforced the benefits of statin in a wide range of patients with renal impairment before maintenance dialysis.

Use of Glucose-Lowering Agents in Diabetes and CKD

Diabetes is the most common cause of kidney failure worldwide. Patients with diabetes and chronic kidney disease (CKD) are also at markedly higher risk of cardiovascular disease, particularly heart failure (HF), and death. Through the processes of gluconeogenesis and glucose reabsorption, the kidney plays a central role in glucose homeostasis. Insulin resistance is an early alteration observed in CKD, worsened by the frequent presence of hypertension, obesity, and ongoing chronic inflammation, and oxidative stress. Management of diabetes in moderate to severe CKD warrants special consideration because of changes in glucose and insulin homeostasis and altered metabolism of glucose-lowering therapies. Kidney failure and initiation of kidney replacement therapy by dialysis adds to management complexity by further limiting therapeutic options, and predisposing individuals to hypoglycemia and hyperglycemia. Glycemic goals should be individualized, considering CKD severity, presence of macrovascular and microvascular complications, and life expectancy. A general hemoglobin A1c (HbA1c) goal of approximately 7% may be appropriate in earlier stages of CKD, with more relaxed targets often appropriate in later stages. Use of sodium glucose cotransporter2 (SGLT2) inhibitors and glucagon like peptide-1 receptor agonists (GLP-1RAs) meaningfully improves kidney and heart outcomes for patients with diabetes and CKD, irrespective of HbA1c targets, and are now part of guideline-directed medical therapy in this high-risk population. Delivery of optimal care for patients with diabetes and CKD will require collaboration across health care specialties and disciplines.

Chronic Kidney Disease as a Cardiovascular Disorder-Tonometry Data Analyses

Tonometry is commonly used to provide efficient and good diagnostics for cardiovascular disease (CVD). There are many advantages of this method, including low cost, non-invasiveness and little time to perform. In this study, the effort was undertaken to check whether tonometry data hides valuable information associated with different stages of chronic kidney disease (CKD) and end-stage renal disease (ESRD) treatment. For this purpose, six groups containing patients at different stages of CKD following different ways of dialysis treatment, as well as patients without CKD but with CVD and healthy volunteers were assessed. It was revealed that each of the studied groups had a unique profile. Only the type of dialysis was indistinguishable a from tonometric perspective (hemodialysis vs. peritoneal dialysis). Several techniques were used to build profiles that independently gave the same outcome: analysis of variance, network correlation structure analysis, multinomial logistic regression, and discrimination analysis. Moreover, to evaluate the classification potential of the discriminatory model, all mentioned techniques were later compared and treated as feature selection methods. Although the results are promising, it could be difficult to express differences as simple mathematical relations. This study shows that artificial intelligence can differentiate between different stages of CKD and patients without CKD. Potential future machine learning models will be able to determine kidney health with high accuracy and thereby classify patients. ClinicalTrials.gov Identifier: NCT05214872.

Effect of Statins on All-Cause Mortality in Adults: A Systematic Review and Meta-Analysis of Propensity Score-Matched Studies

Statins are lipid-lowering medications used for the prevention of cardiovascular disease (CVD), but the pleiotropic effects of statins might be beneficial in other chronic diseases. This meta-analysis investigated the association between statin use and mortality in different chronic conditions. Eligible studies were real-world studies that compared all-cause mortality over at least 12 months between propensity score-matched statin users and non-users. Overall, 54 studies were included: 21 in CVD, 6 in chronic kidney disease, 6 in chronic inflammatory diseases, 3 in cancer, and 18 in other diseases. The risk of all-cause mortality was significantly reduced in statin users (hazard ratio: 0.72, 95% confidence interval: 0.66−0.76). The reduction in mortality risk was similar in CVD studies (0.73, 0.66−0.76) and non-CVD studies (0.70, 0.67−0.79). There were no significant differences in the risk reduction between cohorts with different diseases (p = 0.179). The greatest mortality reduction was seen in studies from Asia (0.61, 0.61−0.73) and the lowest in studies from North America (0.78, 0.73−0.83) and Australia (0.78, 0.62−0.97). There was a significant heterogeneity (I2 = 95%, tau2 = 0.029, p < 0.01). In conclusion, statin use was associated with a significantly reduced risk of all-cause mortality in real-world cohorts with CVD and non-CVD.

Demographic and clinical profile of black patients with chronic kidney disease attending a tertiary hospital in Johannesburg, South Africa

Background

The prevalence of chronic kidney disease (CKD) is increasing worldwide; black patients have an increased risk of developing CKD and end stage kidney disease (ESKD) at significantly higher rates than other races.

Methods

A cross sectional study was carried out on black patients with CKD attending the kidney outpatient clinic at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in South Africa, between September 2019 to March 2020. Demographic and clinical data were extracted from the ongoing kidney outpatient clinic records and interviews, and were filled in a questionnaire. Patients provided blood and urine for laboratory investigations as standard of care, and data were descriptively and inferentially entered into REDcap and analysed using STATA version 17. Multivariable logistic regression analysis was used to identify demographic and clinical variables associated with advanced CKD.

Results

A total of 312 black patients with CKD were enrolled in the study with a median age of 58 (IQR 46–67) years; 58% patients had advanced CKD, 31.5% of whom had grossly increased proteinuria, 96.7% had hypertension, 38.7% had diabetes mellitus and 38.1% had both hypertension and diabetes mellitus. In patients with advanced CKD, the median age was 61 (IQR 51–69) years, eGFR 33 (30–39) mL/min/1.73 m2, serum bicarbonate 22 (IQR 20–24), haemoglobin 12.9 (IQR 11.5–14.0) g/dl and serum uric acid 0.43 (IQR 0.37–0.53). The prevalence of metabolic acidosis was 62.4%, anemia 46.4% and gout 30.9% among those with advanced CKD, while the prevalence of metabolic acidosis and anaemia was 46.6% and 25.9% respectively in those with early CKD. Variables with higher odds for advanced CKD after multivariable logistic regression analysis were hypertension (OR 3.3, 95% CI 1.2–9.2, P = 0.020), diabetes mellitus (OR 1.8, 95% CI 1.1–3.3, P = 0.024), severe proteinuria (OR 3.5, 95% CI 1.9–6.5, P = 0.001), angina (OR 2.5, 95% CI 1.2–5.1, P = 0.008), anaemia (OR 2.9, 95% CI 1.7–4.9, P = 0.001), hyperuricemia (OR 2.4, 95% CI 1.4–4.1, P = 0.001), and metabolic acidosis (OR 2.0, 95% CI 1.2–3.1, P = 0.005). Other associations with advanced CKD were loss of spouse (widow/widower) (OR 3.2, 95% CI 1.4–7.4, P = 0.006), low transferrin (OR 2.4, 95% CI 1.1–5.1, P = 0.028), hyperkalemia (OR 5.4, 95% CI 1.2–24.1, P = 0.029), use of allopurinol (OR 2.4, 95% CI 1.4–4.3, P = 0.005) and doxazosin (OR 1.9, 95% CI 1.2–3.1, P = 0.006).

Conclusion

Hypertension and diabetes mellitus were strongly associated with advanced CKD, suggesting a need for primary and secondary population-based prevention measures. Metabolic acidosis, anemia with low transferrin levels, hyperuricemia and hyperkalemia were highly prevalent in our patients, including those with early CKD, and they were strongly associated with advanced CKD, requiring clinicians and dietitians to be proactive in supporting the needs of CKD patients in meeting their daily dietary requirements towards preventing and slowing the progression of CKD.

Prognostic Impact of Renal Dysfunction at 1-Year Follow-Up on Clinical Outcomes After Percutaneous Coronary Intervention

AIMS

Renal dysfunction is an independent predictor of adverse outcomes in patients with coronary artery disease (CAD). However, the prognostic impact of mid-term changes in renal dysfunction status remains unclear. This study aimed to investigate the impact of mid-term changes in renal dysfunction status on long-term clinical outcomes in CAD patients who underwent percutaneous coronary intervention (PCI).

METHODS

We enrolled 382 consecutive patients with CAD who underwent PCI. Renal dysfunction was defined as a reduced estimated glomerular filtration rate (eGFR) of ＜60 mL/min/1.73m ². Renal dysfunction status was evaluated at baseline and 1-year follow-up after PCI. We divided the study population into three groups: persistent renal dysfunction, new-onset renal dysfunction, and no or improved renal dysfunction at 1-year follow-up as compared with on baseline. The endpoints of this study were composite events, including all-cause death, acute coronary syndrome, target vessel revascularization, and stroke.

RESULTS

At baseline, renal dysfunction was observed in 77 patients (20%). At the 1-year follow-up, new-onset renal dysfunction was observed in 46 patients (12%), and 59 patients (15%) had persistent renal dysfunction. Kaplan-Meier analysis revealed a significantly higher event rate in patients with persistent renal dysfunction and new-onset renal dysfunction (log-rank test, P=0.0003). In the multivariate Cox proportional hazards analysis, persistent renal dysfunction and new-onset renal dysfunction were independently associated with composite events after adjusting for confounding factors (adjusted hazard ratios 4.08 and 2.64, 95% confidence intervals 1.72-9.57 and 1.03-6.31, P=0.0016, P=0.0045, respectively).

CONCLUSION

Persistent and new-onset renal dysfunction at 1-year follow-up were associated with unfavorable outcomes in patients with CAD who underwent PCI.

Prevalence and Clinical Impact of Electrocardiographic Abnormalities in Patients with Chronic Kidney Disease

Chronic kidney disease (CKD) is a strong risk factor for cardiovascular disease. An electrocardiogram (ECG) is a basic test for screening cardiovascular disease. However, the impact of ECG abnormalities on cardiovascular prognosis in patients with CKD is largely unknown. A total of 2442 patients with CKD (stages 3−5) who underwent ECG between 2013 and 2015 were selected from the electronic health record database of the Korea University Anam Hospital. ECG abnormalities were defined using the Minnesota classification. The five-year major adverse cerebrocardiovascular event (MACCE), the composite of death, myocardial infarction (MI), and stroke were analyzed. The five-year incidences for MACCE were 27.7%, 20.8%, and 17.2% in patients with no, minor, and major ECG abnormality (p < 0.01). Kaplan−Meier curves also showed the highest incidence of MI, death, and MACCE in patients with major ECG abnormality. Multivariable Cox regression analysis revealed age, sex, diabetes, CKD stage, hsCRP, antipsychotic use, and major ECG abnormality as independent risk predictors for MACCE (adjusted HR of major ECG abnormality: 1.39, 95% CI: 1.09−1.76, p < 01). Among the detailed ECG diagnoses, sinus tachycardia, myocardial ischemia, atrial premature complex, and right axis deviation were proposed as important ECG diagnoses. The accuracy of cardiovascular risk stratification was improved when the ECG results were added to the conventional SCORE model (net reclassification index 0.07). ECG helps to predict future cerebrocardiovascular events in CKD patients. ECG diagnosis can be useful for cardiovascular risk evaluation in CKD patients when applied in addition to the conventional risk stratification model.

Non-High-Density Lipoprotein Cholesterol and Cardiovascular Outcomes in Chronic Kidney Disease: Results from KNOW-CKD Study

As non-high-density lipoprotein cholesterol (non-HDL-C) levels account for all atherogenic lipoproteins, serum non-HDL-C level has been suggested to be a marker for cardiovascular (CV) risk stratification. Therefore, to unveil the association of serum non-HDL-C levels with CV outcomes in patients with non-dialysis chronic kidney disease (ND-CKD), the patients at stages 1 to 5 (n = 2152) from the Korean Cohort Study for Outcomes in Patients with Chronic Kidney Disease (KNOW-CKD) were prospectively analyzed. The subjects were divided into quintiles by serum non-HDL-C level. The primary outcome was a composite of all-cause death or non-fatal CV events. The median duration of follow-up was 6.940 years. The analysis using the Cox proportional hazard model unveiled that the composite CV event was significantly increased in the 5th quintile (adjusted hazard ratio 2.162, 95% confidence interval 1.174 to 3.981), compared to that of the 3rd quintile. A fully adjusted cubic spline model depicted a non-linear, J-shaped association between non-HDL-C and the risk of a composite CV event. The association remained robust in a series of sensitivity analyses, including the analysis of a cause-specific hazard model. Subgroup analyses reveled that the association is not significantly altered by clinical conditions, including age, gender, body mass index, estimated glomerular filtration rate, and albuminuria. In conclusion, high serum non-HDL-C level increased the risk of adverse CV outcomes among the patients with ND-CKD. Further studies are warranted to define the optimal target range of non-HDL-C levels in this population.

Association between homocysteinemia and mortality in CKD: A propensity-score matched analysis using NHANES-National Death Index

Hyperhomocysteinemia (HHcy) is considered a risk factor for cardiovascular disease (CVD), including chronic kidney disease (CKD). In this study, we investigated the association between levels of serum homocysteine (Hcy) and mortality, inferred from the presence of CKD. Our study included data of 9895 participants from the 1999 to 2016 National Health and Nutrition Examination Surveys (NHANES). Multivariable-adjusted Cox proportional hazard models using propensity-score, were used to examine dose-response associations between Hcy level and mortality. A total of 9895 participants, 1025 (10.3%) participants were diagnosed with CKD. In a multivariate Cox regression analysis including all participants, Hcy level was significantly associated with all-cause mortality in the nonCKD group, compared to the 1st quartile in the fully adjusted model (2nd quartile: hazard ratio (HR) 1.75, 95% confidence interval (CI) 1.348-2.274, P < .001; 3rd quartile: HR 2.22, 95% CI 1.726-2.855, P < .001; 4th quartile: HR 3.77, 95% CI 2.952-4.830, P < .001). However, this finding was not observed in the CKD group. The observed pattern was similar after propensity score matching. In the nonCKD group, overall mortality increased in proportion to Hcy concentration (2nd quartile: HR 2.19, 95% CI 1.299-3.709, P = .003; 3rd quartile: HR 2.60, 95% CI 1.570-4.332, P < .001; 4th quartile: HR 3.72, 95% CI 2.254-6.139, P < .001). However, the risk of all-cause mortality according to the quartile of Hcy level, did not increase in the CKD group. This study found a correlation between the Hcy level and mortality rate only in the nonCKD group. These altered risk factor patterns may be attributed to protein-energy wasting or chronic inflammation status, that is accompanied by CKD.

Role of predictable biomarkers in early detection of cardiovascular events in Chronic Kidney Disease III and IV

This comes about because of a lack of predicted biomarkers in the risk analysis of CVD events in chronic kidney disease (CKD) patients. The present study aimed to determine the clinical utility of independent, predictable biomarkers such as serum creatinine, estimated Glomerular Filtration Rate (eGFR), high sensitive C-Reactive protein (hsCRP), fibrinogen and lipid profile as early predictors of CVD in CKD at stage III/IV.

Methods. This is a case-control study that includes a sample size of 100 patients of cases and 100 patients of controls who were recruited from November 2020 to April 2021, from the Nephrology department of the Visakhapatnam tertiary care teaching hospital, and present with chronic kidney disease – stage III/IV. The subjects’ general conditions (age, gender, height, weight, systolic blood pressure, diastolic blood pressure, and smoking history); underlying diseases (coronary heart disease and diabetes mellitus) were recorded. Fasting venous blood samples were collected under aseptic conditions from the study group after taking informed consent. The measurement of serum creatinine was performed by modification of kinetic Jaffe reaction. The Cockcroft-Gault equation was used to calculate eGFR in both cases and controls. CRP testing was done with a Cobas C311 analyzer, using immunoturbidimetric assay. The Fibroquant kit from Tulip was employed to measure fibrinogen levels in blood samples, and enzymatic methods were applied for lipid profile analysis.

Results. In this study, higher mean values of hsCRP (34.28 mg/dl), increased serum creatinine levels (2.876 mg/dl), reduced eGFR (28.37 mls/min), high levels of serum fibrinogen (291.6 mg/dl), and cholesterol (214.5 mg/dl), HDL (28.34 mg/dl), TG (162.1 mg/dl), VLDL (32.41 mg/dl) and LDL (153.77 mg/dl) were found to be independent predictors of assessment of CV events in patients with CKD stages III and IV as determined by Chi-square test.

Conclusion. A prompt and accurate assessment of cardiovascular risk in CKD patients would enable more aggressive and focused treatment of the individuals who are most in need of preventive interventions to decrease incident rates.

Effects of Short-Term Potassium Chloride Supplementation in Patients with CKD

BACKGROUND

Observational studies suggest that adequate dietary potassium intake (90-120 mmol/day) may be renoprotective, but the effects of increasing dietary potassium and the risk of hyperkalemia are unknown.

METHODS

This is a prespecified analysis of the run-in phase of a clinical trial in which 191 patients (age 68±11 years, 74% males, 86% European ancestry, eGFR 31±9 ml/min per 1.73 m2, 83% renin-angiotensin system inhibitors, 38% diabetes) were treated with 40 mmol potassium chloride (KCl) per day for 2 weeks.

RESULTS

KCl supplementation significantly increased urinary potassium excretion (72±24 to 107±29 mmol/day), plasma potassium (4.3±0.5 to 4.7±0.6 mmol/L), and plasma aldosterone (281 [198-431] to 351 [241-494] ng/L), but had no significant effect on urinary sodium excretion, plasma renin, BP, eGFR, or albuminuria. Furthermore, KCl supplementation increased plasma chloride (104±3 to 105±4 mmol/L) and reduced plasma bicarbonate (24.5±3.4 to 23.7±3.5 mmol/L) and urine pH (all P<0.001), but did not change urinary ammonium excretion. In total, 21 participants (11%) developed hyperkalemia (plasma potassium 5.9±0.4 mmol/L). They were older and had higher baseline plasma potassium.

CONCLUSIONS

In patients with CKD stage G3b-4, increasing dietary potassium intake to recommended levels with potassium chloride supplementation raises plasma potassium by 0.4 mmol/L. This may result in hyperkalemia in older patients or those with higher baseline plasma potassium. Longer-term studies should address whether cardiorenal protection outweighs the risk of hyperkalemia.Clinical trial number: NCT03253172.

Pathomechanism of oxidative stress in cardiovascularrenal remodeling and therapeutic strategies

The high prevalence of cardiovascular disease in patients with chronic kidney disease indicates significant interactions between pathogenic pathways operating in the kidney and heart. These interactions involve all cell types (endothelial cells, smooth muscle cells, macrophages, and others), components of the vasculature, glomeruli, and heart that are susceptible to oxidative damage and structural alterations. A vicious cycle occurs whereby harmful factors such as reactive oxygen species and inflammation damage of vascular structures that themselves become sources of additional dangerous/toxic components released into the local environment. The evidence of this vicious cycle in chronic kidney disease should therefore lead to add other factors to both traditional and nontraditional risk factors. This review will examine the processes occurring during progressive kidney dysfunction with regard to vascular injury, renal remodeling, cardiac hypertrophy, and the transversal role of oxidative stress in the development of these complications.

A promising tool: triglyceride-glucose index to stratify the risk of cardiovascular events in chronic kidney disease

Lipid profile management is one of the crucial components to optimize outcomes in patients with chronic kidney disease (CKD). CKD is associated with poor cardiovascular outcomes due to both a direct cardiovascular impact of CKD and the presence of metabolic comorbidities. Low-density lipoprotein cholesterol is the main target of current lipid-lowering drugs. However, the derangement of lipid metabolism in CKD is more complex. The recently described triglyceride-glucose index (TyG) is associated with cardiovascular outcomes in the general population. In recent studies, the TyG was associated with CKD progression in CKD patients and with cardiovascular death in patients on peritoneal dialysis. Quiroga et al. now show that the TyG is associated with the occurrence of major cardiovascular events in individuals free from diabetes with non-dialysis-dependent CKD.

Association between Anti-Erythropoietin Receptor Antibodies and Cardiac Function in Patients on Hemodialysis: A Multicenter Cross-Sectional Study

Cardiac dysfunction is an important prognostic predictor of cardiovascular mortality in patients on hemodialysis (HD). Erythropoietin (EPO) has been reported to improve cardiac function by binding to the EPO receptor (EPOR) on cardiomyocytes. This study investigated whether anti-EPOR antibodies were associated with left ventricular cardiac function in patients undergoing HD. This multicenter, cross-sectional observational study included 377 patients (median age, 70 years; 267 (70.8%) males) with chronic kidney disease (CKD) undergoing stable maintenance HD. Serum levels of anti-EPOR antibodies were measured, and echocardiography was used to assess the left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF). Anti-EPOR antibodies were found in 17 patients (4.5%). LVMI was greater (median of 135 g/m2 vs. 115 g/m2, p = 0.042), and the prevalence of LVEF < 50% was higher (35.3% vs. 15.6%, p = 0.032) in patients with anti-EPOR antibodies than in those without. Multivariable linear regression and logistic regression analysis (after adjusting for known risk factors of heart failure) revealed that anti-EPOR antibodies were independently associated with LVMI (coefficient 16.2%; 95% confidence interval (CI) 1.0−35.0%, p = 0.043) and LVEF <50% (odds ratio 3.20; 95% CI 1.05−9.73, p = 0.041). Thus, anti-EPOR antibody positivity was associated with left ventricular dysfunction in patients undergoing HD.

Predictors of Postoperative Delirium in Older Patients Undergoing Elective Spine Surgery

Introduction

This prospective study was conducted to investigate the prevalence and predictors of postoperative delirium (POD) in a cohort of patients aged ≥65 years who were scheduled to undergo elective spine surgery.

Methods

Patients aged ≥65 years who were scheduled to undergo elective spine surgery from February 2018 to May 2019 were prospectively recruited for this study. Delirium was diagnosed according to the Confusion Assessment Method algorithm. Candidate predictors included patient characteristics, comorbidities, surgical time, blood loss, preoperative laboratory parameters, and preoperative cognitive function, as assessed by the Mini-Cog test. These variables were compared between patients with and without POD. Multivariate logistic regression was performed to identify the independent predictors of POD. For the continuous variables, a receiver operating characteristic curve was used to determine the optimal cutoff value for predicting POD.

Results

Of the 106 patients included in the study, 12 (11.3%) patients developed POD, with a median time to onset of 3 d and median duration of 2 d. After adjusting for confounders, the occurrence of POD was independently associated with older age, a higher blood urea nitrogen (BUN) concentration, and a lower Mini-Cog score. The optimal cutoff point of the Mini-Cog score for predicting the occurrence of POD was ≤3.

Conclusions

POD was a common complication after spine surgery, showing an incidence of 11.3% in this study. Older age, a higher BUN concentration, and impaired cognition, as defined by the Mini-Cog, were independent predictors of POD. The current results may be useful for early identification of patients at risk of POD and facilitation of targeted interventions for preventing POD or mitigating its severity.

Special Issue on "Advances in Cholesterol and Lipid Metabolism"

Cholesterol and lipid metabolism is a broad topic that encompasses multiple aspects of cellular function in every organ [...].

Mechanisms of cardio-renal protection of sodium-glucose cotransporter-2 inhibitors

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are glucose-lowering drugs used in the treatment of type 2 diabetes (T2D) that have shown additional cardiac and renal benefits. The mechanisms of SGLT2i-mediated cardiorenal protection include blood pressure lowering and endothelial function improvements, enhancement of cardiac and renal hemodynamics, optimization of energetic efficiency through metabolic changes and cellular ion exchanges, reduction of inflammation and oxidative stress with consequent fibrosis reduction, and sympathetic activity modulation. This review explores the most recent data regarding the physiological mechanisms of SGLT2i cardiac and renal benefits, which lie at the root of the solid clinical evidence on cardiorenal protection, making SGLT2i a promising new pharmacological approach to the treatment of patients at high risk of cardiorenal syndrome.

Coronary Artery Calcification Score and the Progression of Chronic Kidney Disease

BACKGROUND

An elevated coronary artery calcification score (CACS) is associated with increased cardiovascular disease risk in patients with CKD. However, the relationship between CACS and CKD progression has not been elucidated.

METHODS

We studied 1936 participants with CKD (stages G1-G5 without kidney replacement therapy) enrolled in the KoreaN Cohort Study for Outcome in Patients With CKD. The main predictor was Agatston CACS categories at baseline (0 AU, 1-100 AU, and >100 AU). The primary outcome was CKD progression, defined as a ≥50% decline in eGFR or the onset of kidney failure with replacement therapy.

RESULTS

During 8130 person-years of follow-up, the primary outcome occurred in 584 (30.2%) patients. In the adjusted cause-specific hazard model, CACS of 1-100 AU (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.04 to 1.61) and CACS >100 AU (HR, 1.42; 95% CI, 1.10 to 1.82) were associated with a significantly higher risk of the primary outcome. The HR associated with per 1-SD log of CACS was 1.13 (95% CI, 1.03 to 1.24). When nonfatal cardiovascular events were treated as a time-varying covariate, CACS of 1-100 AU (HR, 1.31; 95% CI, 1.07 to 1.60) and CACS >100 AU (HR, 1.46; 95% CI, 1.16 to 1.85) were also associated with a higher risk of CKD progression. The association was stronger in older patients, in those with type 2 diabetes, and in those not using antiplatelet drugs. Furthermore, patients with higher CACS had a significantly larger eGFR decline rate.

CONCLUSION

Our findings suggest that a high CACS is associated with significantly increased risk of adverse kidney outcomes and CKD progression.

Pro-oxidative priming but maintained cardiac function in a broad spectrum of murine models of chronic kidney disease

Aims

Patients with chronic kidney disease (CKD) have an increased risk of cardiovascular events and exhibit myocardial changes including left ventricular (LV) hypertrophy and fibrosis, overall referred to as ‘uremic cardiomyopathy’. Although different CKD animal models have been studied for cardiac effects, lack of consistent reporting on cardiac function and pathology complicates clear comparison of these models. Therefore, this study aimed at a systematic and comprehensive comparison of cardiac function and cardiac pathophysiological characteristics in eight different CKD models and mouse strains, with a main focus on adenine-induced CKD.

Methods and results

CKD of different severity and duration was induced by subtotal nephrectomy or adenine-rich diet in various strains (C57BL/6J, C57BL/6 N, hyperlipidemic C57BL/6J ApoE^−/−, 129/Sv), followed by the analysis of kidney function and morphology, blood pressure, cardiac function, cardiac hypertrophy, fibrosis, myocardial calcification and inflammation using functional, histological and molecular techniques, including cardiac gene expression profiling supplemented by oxidative stress analysis. Intriguingly, despite uremia of variable degree, neither cardiac dysfunction, hypertrophy nor interstitial fibrosis were observed. However, already moderate CKD altered cardiac oxidative stress responses and enhanced oxidative stress markers in each mouse strain, with cardiac RNA sequencing revealing activation of oxidative stress signaling as well as anti-inflammatory feedback responses.

Conclusion

This study considerably expands the knowledge on strain- and protocol-specific differences in the field of cardiorenal research and reveals that several weeks of at least moderate experimental CKD increase oxidative stress responses in the heart in a broad spectrum of mouse models. However, this was insufficient to induce relevant systolic or diastolic dysfunction, suggesting that additional “hits” are required to induce uremic cardiomyopathy.

Translational perspective

Patients with chronic kidney disease (CKD) have an increased risk of cardiovascular adverse events and exhibit myocardial changes, overall referred to as ‘uremic cardiomyopathy’. We revealed that CKD increases cardiac oxidative stress responses in the heart. Nonetheless, several weeks of at least moderate experimental CKD do not necessarily trigger cardiac dysfunction and remodeling, suggesting that additional “hits” are required to induce uremic cardiomyopathy in the clinical setting. Whether the altered cardiac oxidative stress balance in CKD may increase the risk and extent of cardiovascular damage upon additional cardiovascular risk factors and/or events will be addressed in future studies.

•

Development of a CKD mouse model with a clear cardiac functional or morphological phenotype is challenging.

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Cardiac oxidative stress response as well as oxidative stress markers are increased in a broad spectrum of CKD mouse models.

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Our findings suggest need of additional cardiovascular hits to clearly induce uremic cardiomyopathy as observed in patients.

Clinical and Quality-of-Life Outcomes Following Invasive vs Conservative Treatment of Patients With Chronic Coronary Disease Across the Spectrum of Kidney Function

Importance

Prior trials of invasive vs conservative management of chronic coronary disease (CCD) have not enrolled patients with severe chronic kidney disease (CKD). As such, outcomes across kidney function are not well characterized.

Objectives

To evaluate clinical and quality-of-life (QoL) outcomes across the spectrum of CKD following conservative and invasive treatment strategies.

Design, Setting, and Participants

Participants from the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) and ISCHEMIA-Chronic Kidney Disease (CKD) trials were categorized by CKD stage: stage 1 (estimated glomerular filtration rate [eGFR] 90 mL/min/1.73m2 or greater), stage 2 (eGFR 60-89 mL/min/1.73m2), stage 3 (eGFR 30-59 mL/min/1.73m2), stage 4 (eGFR 15-29 mL/min/1.73m2), or stage 5 (eGFR less than 15 mL/min/1.73m2 or receiving dialysis). Enrollment took place from July 26, 2012, through January 31, 2018, with a median follow-up of 3.1 years. Data were analyzed from January 2020 to May 2021.

Interventions

Initial invasive management of coronary angiography and revascularization with guideline-directed medical therapy (GDMT) vs initial conservative management of GDMT alone.

Main Outcomes and Measures

The primary clinical outcome was a composite of death or nonfatal myocardial infarction (MI). The primary QoL outcome was the Seattle Angina Questionnaire (SAQ) summary score.

Results

Among the 5956 participants included in this analysis (mean [SD] age, 64 [10] years; 1410 [24%] female and 4546 [76%] male), 1889 (32%), 2551 (43%), 738 (12%), 311 (5%), and 467 (8%) were in CKD stages 1, 2, 3, 4, and 5, respectively. By self-report, 18 participants (<1%) were American Indian or Alaska Native; 1676 (29%), Asian; 267 (5%), Black; 861 (16%), Hispanic or Latino; 18 (<1%), Native Hawaiian or Other Pacific Islander; 3884 (66%), White; and 13 (<1%), multiple races or ethnicities. There was a monotonic increase in risk of the primary composite end point (3-year rates, 9.52%, 10.72%, 18.42%, 34.21%, and 38.01% respectively), death, cardiovascular death, MI, and stroke in individuals with higher CKD stages. Invasive management was associated with an increase in stroke (3-year event rate difference, 1%; 95% CI, 0.3 to 1.7) and procedural MI (1.6%; 95% CI, 0.9 to 2.3) and a decrease in spontaneous MI (-2.5%; 95% CI, -3.9 to -1.1) with no difference in other outcomes; the effect was similar across CKD stages. There was heterogeneity of treatment effect for QoL outcomes such that invasive management was associated with an improvement in angina-related QoL in individuals with CKD stages 1 to 3 and not in those with CKD stages 4 to 5.

Conclusions and Relevance

Among participants with CCD, event rates were inversely proportional to kidney function. Invasive management was associated with an increase in stroke and procedural MI and a reduced risk in spontaneous MI, and the effect was similar across CKD stages with no difference in other outcomes, including death. The benefit for QoL with invasive management was not observed in individuals with poorer kidney function.