Premature cardiovascular disease in chronic renal failure

Predictive value of triglyceride/glucose index for cardiac outcomes in non-diabetic renal transplant recipients

OBJECTIVES

Insulin resistance (IR) is associated with an increased risk of adverse cardiovascular outcomes. The triglyceride-glucose index (TyG index) is a reliable marker of IR. No study has examined the impact of the TyG index on major adverse cardiac and cerebrovascular events (MACCEs) in RTRs. Therefore, this study aimed to investigate the predictive value of the TyG index for MACCEs in RTRs.

MATERIALS AND METHODS

Non-diabetic patients undergoing renal transplantation were retrospectively enrolled. The patients were divided into two groups according to MACCE development. The cut-off value of the TyG index for MACCE was conducted.

RESULTS

The mean age of 522 patients was 41 (31-51) years, and 349 (66.9%) were male. During the 5.4-year follow-up, 84 (16%) MACCE were recorded. TyG index was significantly higher in the group that developed MACCE (p < 0,001). Cox regression analysis revealed that TyG index [HR: 3.297 (1.228-8.855), p = 0.018], left ventricle ejection fraction [HR: 0.934 (0.900-0.968), p < 0.001], cadaveric transplantation [HR: 8.886 (4.764-16.576), p < 0.001], graft survey [HR: 0.608 (0.542-0.682), p < 0.001)], and smoking [HR: 1.965 (1.117-3.456), p = 0.019] were independent predictors of MACCEs in nondiabetic RTRs.

CONCLUSION

TyG index is an independent predictor of MACCEs in non-diabetic RTRs. The widespread use of the TyG index may positively affect long-term treatment costs and survival.

Role of CaMKII in diabetes induced vascular injury and its interaction with anti-diabetes therapy

Diabetes mellitus is a metabolic disorder denoted by chronic hyperglycemia that drives maladaptive structural changes and functional damage to the vasculature. Attenuation of this pathological remodeling of blood vessels remains an unmet target owing to paucity of information on the metabolic signatures of this process. Ca2+/calmodulin-dependent kinase II (CaMKII) is expressed in the vasculature and is implicated in the control of blood vessels homeostasis. Recently, CaMKII has attracted a special attention in view of its chronic upregulated activity in diabetic tissues, yet its role in the diabetic vasculature remains under investigation.This review highlights the physiological and pathological actions of CaMKII in the diabetic vasculature, with focus on the control of the dialogue between endothelial (EC) and vascular smooth muscle cells (VSMC). Activation of CaMKII enhances EC and VSMC proliferation and migration, and increases the production of extracellular matrix which leads to maladaptive remodeling of vessels. This is manifested by activation of genes/proteins implicated in the control of the cell cycle, cytoskeleton organization, proliferation, migration, and inflammation. Endothelial dysfunction is paralleled by impaired nitric oxide signaling, which is also influenced by CaMKII signaling (activation/oxidation). The efficiency of CaMKII inhibitors is currently being tested in animal models, with a focus on the genetic pathways involved in the regulation of CaMKII expression (microRNAs and single nucleotide polymorphisms). Interestingly, studies highlight an interaction between the anti-diabetic drugs and CaMKII expression/activity which requires further investigation. Together, the studies reviewed herein may guide pharmacological approaches to improve health-related outcomes in patients with diabetes.

Hexasodium fytate exposure-response correlations in a randomized, placebo-controlled study of patients on dialysis with cardiovascular calcification

Background: Patients receiving dialysis have high cardiovascular risk in part due to extensive vascular calcification. In the CaLIPSO study, infusion of hexasodium fytate (SNF472), the hexasodium salt of inositol hexaphosphate, for 52 weeks thrice weekly during hemodialysis significantly reduced progression of coronary artery calcification (CAC). This report examines pharmacokinetic/pharmacodynamic (PK/PD) and exposure-efficacy in CaLIPSO. Methods: We measured hexasodium fytate plasma concentrations (PK) by validated liquid chromatography-mass spectroscopy, and hydroxyapatite crystallization in plasma (PD) by validated spectrophotometry. Analyses included patients evaluable for PK, PD, and CAC change (per-protocol analysis). We developed a simple Emax model for maximum concentration (Cmax) and PD effect, and linear and non-linear Emax models for exposure-efficacy among individual average Cmax and absolute and percent changes in CAC score from baseline to week 52. Results: Among evaluable patients receiving placebo (n = 15), 300 mg (n = 20), or 600 mg (n = 20), average Cmax across visits was not quantifiable (<0.76 μM), 15 μM, and 46 μM, respectively. These results suggest a more-than-proportional increase, without accumulation, with a Cmax ratio of approximately 3 for the doses administered. Average inhibition of hydroxyapatite crystallization was 15%, 61%, and 75%, respectively, and similar across visits. Simple Emax models described 80% maximal effect at exposures >21.9 µM and a plateau in exposure-efficacy above the third quartile of Cmax (≥32 µM). Conclusion: Hexasodium fytate has exposure-dependent effects on hydroxyapatite crystallization and progression of cardiovascular calcification. Simple Emax models show robust relations among exposure, inhibition of hydroxyapatite crystallization, and change in CAC volume. Clinical Trial Registration: https://www.clinicaltrials.gov; identifier NCT02966028.

Baseline and oxidatively damaged DNA in end-stage renal disease patients on varied hemodialysis regimens: a comet assay assessment

Global estimates exhibit that one million people have end-stage renal disease, a disease-state characterized by irreversible loss of kidney structure and function, thus necessitating renal replacement therapy. The disease-state, oxidative stress, inflammatory responses, as well as the treatment procedure can have damaging effects on the genetic material. Therefore, the present study was carried out to investigate DNA damage (basal and oxidative) using the comet assay in peripheral blood leukocytes of patients (n = 200) with stage V Chronic Kidney Disease (on dialysis and those recommended but yet to initiate dialysis) and compare it to that in controls (n = 210). Basal DNA damage was significantly elevated (1.13x, p ≤ 0.001) in patients (46.23 ± 0.58% DNA in tail) compared to controls (40.85 ± 0.61% DNA in tail). Oxidative DNA damage was also significantly (p ≤ 0.001) higher in patients (9.18 ± 0.49 vs. 2.59 ± 0.19% tail DNA) compared to controls. Twice-a-week dialysis regimen patients had significantly elevated % tail DNA and Damage Index compared to the non-dialyzed and to the once-a-week dialysis group implying dialysis- induced mechanical stress and blood-dialyzer membrane interactions as probable contributors to elevated DNA damage. The present study with a statistically significant power implies higher disease-associated as well as maintenance therapy (hemodialysis)-induced basal and oxidatively damaged DNA, which if not repaired has the potential to initiate carcinogenesis. These findings mark the need for improvement and development of interventional therapies for delaying disease progression and associated co-morbidities so as to improve life expectancy of patients with kidney disease.

Protein Biomarkers and Major Cardiovascular Events in Older People With Advanced CKD: The European Quality (EQUAL) Study

Rationale & Objective

Cardiovascular disease is the leading cause of morbidity and mortality in chronic kidney disease (CKD). We investigated 184 inflammatory and cardiovascular proteins to determine their potential as biomarkers for major cardiovascular events (MACEs).

Study Design

The European Quality (EQUAL) is an observational cohort study that enrolled people aged ≥65 years with an estimated glomerular filtration rate ≤20 mL/min/1.73 m2.

Setting & Participants

Recruited participants were split into the discovery (n = 611) and replication cohorts (n = 292).

Exposure

Levels of 184 blood proteins were measured at the baseline visit, and each protein was analyzed individually.

Outcome

MACE.

Analytical Approach

Cox proportional hazard models adjusted for age, sex, estimated glomerular filtration rate, previous MACE, and country were used to determine the risk of MACE. Proteins with false discovery rate adjusted P values of <0.05 in the discovery cohort were tested in the replication cohort. Sensitivity analyses were performed by adjusting for traditional risk factors, CKD-specific risk factors, and level of proteinuria and segregating atherosclerotic and nonatherosclerotic MACE.

Results

During a median follow-up of 2.9 years, 349 people (39%) experienced a MACE. Forty-eight proteins were associated with MACE in the discovery cohort; 9 of these were reproduced in the replication cohort. Three of these proteins maintained a strong association with MACE after adjustment for traditional and CKD-specific risk factors and proteinuria. Tenascin (TNC), fibroblast growth factor-23 (FGF-23), and V-set and immunoglobulin domain-containing protein 2 (VSIG2) were associated with both atherosclerotic and nonatherosclerotic MACE. All replicated proteins except carbonic anhydrase 1 and carbonic anhydrase 3 were associated with nonatherosclerotic MACE.

Limitations

Single protein concentration measurements and limited follow-up time.

Conclusions

Our findings corroborate previously reported relationships between FGF-23, vascular cell adhesion protein-1, TNC, and placental growth factor with cardiovascular outcomes in CKD. We identify 5 proteins not previously linked with MACE in CKD that may be targets for future therapies.

Plain-Language Summary

Kidney disease increases the risk of heart disease, stroke, and other vascular conditions. Blood tests that predict the likelihood of these problems may help to guide treatment, but studies are needed in people with kidney disease. We analyzed blood tests from older people with kidney disease, looking for proteins associated with higher risk of these conditions. Nine proteins were identified, of which 3 showed a strong effect after all other information was considered. This work supports previous research regarding 4 of these proteins and identifies 5 additional proteins that may be associated with higher risk. Further work is needed to confirm our findings and to determine whether these proteins can be used to guide treatment.

Effect of iron administration on the aortic iron content and vascular calcification in phosphorus-loaded chronic kidney disease rats

BACKGROUND

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with chronic kidney disease (CKD) and could be related to oxidative stress. Vascular calcification (VC) has been established as a critical risk factor for accelerated CVD. In CKD, phosphorus (Pi), iron (Fe) and Nrf2 are modulators of VC and important agonists and antagonists of oxidative stress. The aim of this study was to determine whether Fe administration, which is commonly used to treat renal anemia, affects aortic Fe overload and VC, and whether Nrf2 and its related genes, ferritin H and HIF-1α, are involved in the development of VC.

METHODS

A CKD model was created in rats by administering adenine and simultaneously feeding a high-Pi diet. In addition to control and CKD rats without Fe administration (No-Fe group), Fe was administered orally (PO-Fe group) or intraperitoneally (IP-Fe group) to CKD animals to clarify the effects of Fe administration on the aortic Fe and calcium (Ca) contents and the involvement of Nrf2 and its induced antioxidative proteins, ferritin H and HIF-1α, in VC.

RESULTS

The aortic Fe content increased significantly in the IP-Fe group, which was closely correlated with liver HAMP (hepcidin) expression in all animals. Fe administration had no significant effect on the aortic Ca and Pi contents regardless of the route of Fe administration. The aortic mRNA level of Nrf2 was significantly increased in the IP-Fe group and correlated with serum Pi levels and aortic Fe contents, which could respond to oxidative stress. Notably, the mRNA level of Nrf2 was also significantly correlated with the mRNA levels of ferritin H and HIF-1α. Since we could not measure Nrf2 protein levels in this study, we confirmed the upregulation of HMOX1 and NQO1 mRNA expression in parallel with Nrf2 mRNA.

CONCLUSION

Parenteral Fe administration increased aortic Fe in parallel with the liver HAMP mRNA level but did not affect VC. Aortic Nrf2 mRNA levels correlated significantly with aortic Fe and serum Pi levels and with aortic mRNA levels of ferritin H and HIF-1α as well as HMOX1 and NQO1.

Association Between Cardiovascular Disease and Chronic Kidney Disease Prevalence and Characteristics in Saudi Arabia

Introduction Cardiovascular disease (CVD), including coronary artery disease (CAD), is a leading global cause of death. Chronic kidney disease (CKD) is a significant risk factor, particularly in data-scarce Saudi Arabia, due to shared risk factors. A study aims to assess the CVD-CKD relationship, identifying clinical characteristics and risk factors to improve prevention and care in this context, filling a knowledge gap in Saudi Arabia's healthcare map. Methodology It is a single-center retrospective study aimed at evaluating the relationship between cardiovascular disease and chronic kidney disease, conducted between January 2023 and October 2023. Data was sourced from patient files using a data sheet based on a previous study. The data was cleaned in MS Excel (Redmond, USA) and analyzed in IBM Corp. Released 2022. IBM SPSS Statistics for Windows, Version 29.0. Armonk, NY: IBM Corp. Results Our study contains predominantly males (61%), aged 61-80 (54.1%), with a normal body mass index (BMI) (<25) (61.5%) and a high prevalence of smoking (72.3%). Diabetes, hypertension, and smoking were prevalent risk factors. The relationship between CAD severity, renal dysfunction, and ejection fraction (EF) was explored, emphasizing the association between declining renal function and more advanced CAD stages, as well as the decline in estimated glomerular filtration rate (eGFR) with decreasing EF. Age, smoking, CAD, and decreasing EF were linked to renal dysfunction, while smoking, stroke history, peripheral vascular disease (PVD), BMI, and decreasing EF were associated with CAD stage severity. Conclusion Our study explored that as CAD severity increases, renal function decreases, showing both CVD and CKD connected with each other, and a similar correlation occurs between decreasing EF and decreasing eGFR, revealing significant associations with various risk factors. Further research is warranted to explore potential interventions aimed at mitigating the synergistic impact of CVD and CKD on patient morbidity and mortality.

Prognostic Significance of Amino Acid and Biogenic Amines Profiling in Chronic Kidney Disease

There is a pressing need for more precise biomarkers of chronic kidney disease (CKD). Plasma samples from 820 subjects [231 with CKD, 325 with end-stage kidney disease (ESKD) and 264 controls] were analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) to determine a metabolic profile of 28 amino acids (AAs) and biogenic amines to test their value as markers of CKD risk and progression. The kynurenine/tryptophan ratio showed the strongest correlation with estimated glomerular filtration rate values (coefficient = -0.731, p < 0.0001). Models created with orthogonal partial least squares-discriminant analysis (OPLS-DA) containing the metabolic signature showed a high goodness of fit and predictability for controls/CKD (R2X:0.73:R2Y:0.92:Q2:0.92, p < 0.0001) and lower values for CKD/ESKD (R2X:0.56:R2Y:0.59:Q2:0.55, p < 0.0001). Based on generated VIP scores, the most relevant markers for segregating samples into control/CKD and CKD/ESKD groups were citrulline (1.63) and tryptophan (1.47), respectively. ROC analysis showed that the addition of the metabolic profile to a model including CKD classic risk factors improved the AUC from 86.7% (83.6-89.9) to 100% (100-100) for CKD risk (p < 0.0001) and from 63.0% (58.2-67.8) to 96.5% (95.3-97.8) for the risk of progression from CKD to ESKD (p < 0.0001). Plasma concentrations of AAs and related amines may be useful as diagnostic biomarkers of kidney disease, both for CKD risk and for progression of CKD patients to ESKD.

Circulating microRNA Profiles for Premature Cardiovascular Death in Patients with Kidney Failure with Replacement Therapy

INTRODUCTION

Patients with kidney failure with replacement therapy (KFRT) suffer from a disproportionately high cardiovascular disease burden. Circulating small non-coding RNAs (c-sncRNAs) have emerged as novel epigenetic regulators and are suggested as novel biomarkers and therapeutic targets for cardiovascular disease; however, little is known about the associations of c-sncRNAs with premature cardiovascular death in KFRT.

METHODS

In a pilot case-control study of 50 hemodialysis patients who died of cardiovascular events as cases, and 50 matched hemodialysis controls who remained alive during a median follow-up of 2.0 years, we performed c-sncRNAs profiles using next-generation sequencing to identify differentially expressed circulating microRNAs (c-miRNAs) between the plasma of cases and that of controls. mRNA target prediction and pathway enrichment analysis were performed to examine the functional relevance of differentially expressed c-miRNAs to cardiovascular pathophysiology. The association of differentially expressed c-miRNAs with cardiovascular mortality was examined using multivariable conditional logistic regression.

RESULTS

The patient characteristics were similar between cases and controls, with a mean age of 63 years, 48% male, and 54% African American in both groups. We detected a total of 613 miRNAs in the plasma, among which five miRNAs (i.e., miR-129-1-5p, miR-500b-3p, miR-125b-1-3p, miR-3648-2-5p, and miR-3150b-3p) were identified to be differentially expressed between cases and controls with cut-offs of p < 0.05 and log2 fold-change (log2FC) > 1. When using more stringent cut-offs of p-adjusted < 0.05 and log2FC > 1, only miR-129-1-5p remained significantly differentially expressed, with higher levels of miR-129-1-5p in the cases than in the controls. The pathway enrichment analysis using predicted miR-129-1-5p mRNA targets demonstrated enrichment in adrenergic signaling in cardiomyocytes, arrhythmogenic right ventricular cardiomyopathy, and oxytocin signaling pathways. In parallel, the circulating miR-129-1-5p levels were significantly associated with the risk of cardiovascular death (adjusted OR [95% CI], 1.68 [1.01-2.81] for one increase in log-transformed miR-129-1-5p counts), independent of potential confounders.

CONCLUSIONS

Circulating miR-129-1-5p may serve as a novel biomarker for premature cardiovascular death in KFRT.

Metabolomics profiling distinctively identified end-stage renal disease patients from chronic kidney disease patients

Chronic kidney disease (CKD) is a serious public health problem characterized by progressive kidney function loss leading to end-stage renal disease (ESRD) that demands dialysis or kidney transplantation. Early detection can prevent or delay progression to ESRD. The study aimed to gain new insights into the perturbed biochemical reactions and to identify novel distinct biomarkers between ESRD and CKD. Serum samples of 32 patients with ESRD (n = 13) and CKD (n = 19) were analyzed using chemical isotope labeling liquid chromatography-mass spectrometry metabolomics approach. A total of 193 metabolites were significantly altered in ESRD compared to CKD and were mainly involved in aminoacyl-tRNA biosynthesis, branched-chain amino acid (BCAA) biosynthesis, taurine metabolism, and tryptophan metabolism. Three kynurenine derivatives, namely, 2-aminobenzoic acid, xanthurenic acid, and hydroxypicolinic acid were upregulated in ESRD compared to CKD due to the significant decrease in glomerular filtration rate with the progression of CKD to ESRD. N-Hydroxy-isoleucine, 2-aminobenzoic acid, and picolinic acid yielded AUC > 0.99 when analyzed using Receiver Operating Characteristic (ROC) analysis. Our findings suggest that inhibiting the kynurenine pathway might be a promising target to delay CKD progression and that metabolites with high discriminative ability might serve as potential prognostic biomarkers to monitor the progression of CKD to ESRD or used in combination with current markers to indicate the status of kidney damage better.

A Systematic Review and Meta-Analysis of Posttransplant Anemia With Overall Mortality and Cardiovascular Outcomes Among Kidney Transplant Recipients

Introduction: Posttransplant anemia is a common finding after kidney transplantation. A previous meta-analysis reported an association between anemia and graft loss. However, data on cardiovascular outcomes have not yet been reported. Objective: We conducted an updated meta-analysis to examine the association between posttransplant anemia and outcomes after transplantation including cardiovascular mortality in adult kidney transplant recipients. Methods: We comprehensively searched the databases of MEDLINE and EMBASE from inception to November 2021. Data from each study were combined using the random-effects model. Generic inverse variance method of DerSimonian and Laird was employed to calculate the risk ratios and 95% CIs. Results: Seventeen studies from August 2006 to April 2019 were included (16 463 kidney transplantation recipients). Posttransplant anemia was associated with overall mortality (pooled risk ratio = 1.72 [1.39, 2.13], I² = 56%), graft loss (pooled risk ratio = 2.28 [1.77, 2.93], I² = 94%), cardiovascular death (pooled risk ratio = 2.06 [1.35, 3.16], I² = 0%), and cardiovascular events (pooled risk ratio = 1.33 [1.10, 1.61], I² = 0%). Early anemia (≤6 months), compared with late anemia (>6 months), has higher risk of overall mortality and graft loss with a pooled risk ratio of 2.63 (95% CI 1.79-3.86; I² = 0%) and 2.96 (95% CI 2.29-3.82; I² = 0%), respectively. Discussion: In addition to increased risk of graft loss, our updated meta-analysis demonstrated that posttransplant anemia was significantly associated with poor outcomes after kidney transplantation including overall mortality, graft loss, cardiovascular death, and cardiovascular events. Future studies are required to assess the effects of treatment strategies for posttransplant anemia on posttransplant outcomes including cardiovascular mortality.

Electrocardiographic substrates of arrhythmias in patients with end-stage and chronic kidney diseases: a case-control study

BACKGROUND

Cardiovascular disease (CVD) is the most common cause of death in patients with renal diseases. Cardiac arrhythmia and sudden cardiac death are particularly important, and the burden is higher in patients on hemodialysis. The aim of this study is to compare specific ECG changes as markers of arrhythmias in patients with CKD and patients with end-stage renal disease (ESRD); all without clinically manifest heart disease, with normal control subjects.

RESULTS

Seventy-five ESRD patients on regular hemodialysis, 75 patients with stage 3-5 CKD and 40 healthy control subjects were included. All candidates were subjected to thorough clinical evaluation and laboratory tests including serum creatinine, glomerular filtration rate calculation, serum potassium, magnesium, calcium, phosphorus, iron, parathyroid hormone, and total iron binding capacity (TIBC). Resting twelve-lead ECG was done to calculate P wave dispersion (P-WD), corrected QT interval, QTc dispersion, Tpeak-Tend interval (Tp-e), and Tp-e/QT. Patients with ESRD had a significantly higher QTc dispersion (p < 0.001) and P-WD (p = 0.001) when compared to the other 2 groups. In the ESRD group, males had a significantly higher P-WD (p = 0.045), insignificantly higher QTc dispersion (p = 0.445), and insignificantly lower Tp-e/QT ratio (p = 0.252) as compared to females. Multivariate linear regression analysis for ESRD patients showed that serum creatinine (β = 0.279, p = 0.012) and transferrin saturation (β =  - 0.333, p = 0.003) were independent predictors of increased QTc dispersion while ejection fraction (β = 0.320, p = 0.002), hypertension (β =  - 0.319, p = 0.002), hemoglobin level (β =  - 0.345, p = 0.001), male gender (β =  - 0.274, p = 0.009) and TIBC (β =  - 0.220, p = 0.030) were independent predictors of increased P wave dispersion. In the CKD group, TIBC (β =  - 0.285, p = 0.013) was an independent predictor of QTc dispersion while serum calcium (β = 0.320, p = 0.002) and male gender (β =  - 0.274, p = 0.009) were independent predictors of Tp-e/QT ratio.

CONCLUSIONS

Patients with stage 3-5 CKD and those with ESRD on regular hemodialysis exhibit significant ECG changes that are considered substrates for ventricular as well as supraventricular arrhythmias. Those changes were more evident in patients on hemodialysis.

De novo major cardiovascular events in kidney transplant recipients: a comparative matched cohort study

BACKGROUND

Although cardiovascular disease is known to be one of the leading causes of death after kidney transplantation (KT), evidence on the risk difference of de novo major adverse cardiovascular events (MACEs) in kidney transplant recipients (KTRs) compared with that in dialysis patients or the general population (GP) remains rare.

METHODS

We identified KTRs using the nationwide health insurance database in South Korea and then 1:1 matched them with the dialysis and GP controls without a pre-existing MACE. The primary endpoint was defined as de novo MACEs consisting of myocardial infarction, coronary revascularization and ischemic stroke. The secondary endpoints were all-cause mortality and death-censored graft failure (DCGF) in KTRs.

RESULTS

We included 4156 individuals in each of the three groups and followed them up for 4.7 years. De novo MACEs occurred in 3.7, 21.7 and 2.5 individuals per 1000 person-years in the KTRs, dialysis controls and GP controls, respectively. KTRs showed a lower MACE risk {adjusted hazard ratio (aHR) 0.16 [95% confidence interval (CI) 0.12-0.20], P < .001} than dialysis controls, whereas a similar MACE risk to GP controls [aHR 0.81 (95% CI 0.52-1.27), P = .365]. In addition, KTRs showed a similar MACE risk compared with the GP group, regardless of age, sex and the presence of comorbidities, including hypertension, diabetes and dyslipidemia. Among KTRs, de novo MACEs were associated with an increased risk of all-cause mortality, but not with DCGF.

CONCLUSIONS

De novo MACEs in KTRs were much lower than that in dialysis patients and had a similar risk to the GP, but once it occurred it caused elevated mortality risk in KTRs.

GC–MS and Network Pharmacology Analysis of the Ayurvedic Fermented Medicine, Chandanasava, Against Chronic Kidney and Cardiovascular Diseases

Chandanasava is an Ayurvedic polyherbal fermented traditional medicine (FTM) used by traditional practitioners for millennia. Nevertheless, the mode of action and functional targets are still unknown. The current study includes a pharmacological network analysis to identify the Chandanasava compounds interacting with target proteins involved in chronic kidney disease (CKD) and cardiovascular disease (CVD). Sixty-one Chandanasava phytochemicals were obtained by GC-MS and screened using the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP). The disease target genes were obtained from DisGeNET and GeneCards databases. Forty-five phytocompounds and 135 potential targets were screened for CKD and CVD target proteins and protein interaction networks were constructed. The pharmacological network was deciphered employing target proteins involved in the mechanical action of Chandanasava. The results indicated that 10 bioactive compounds exhibited higher binding affinity patterns with the screened 42 CKD and CVD target proteins. Gene Ontology and KEGG analysis revealed target pathways involved in CKD and CVD, which were further explored by detailed analysis and network-coupled drug profile screening. The molecular docking results showed piperine and melatonin as effective inhibitors/regulators of the hub genes of CKD and CVD. The current study establishing authentic bioactive compounds in FTM is based on deeper insights into recognized Ayurvedic medicines. Representing the workflow of the network pharmacological analysis.

Cardiovascular Risk Following Conversion to Belatacept From a Calcineurin Inhibitor in Kidney Transplant Recipients: A Randomized Clinical Trial

Rationale & Objective

In kidney transplant recipients (KTRs), a belatacept-based immunosuppressive regimen is associated with beneficial effects on cardiovascular (CV) risk factors compared with calcineurin inhibitor (CNI)-based regimens. Our objective was to compare the calculated CV risk between belatacept and CNI (predominantly tacrolimus) treatments using a validated model developed for KTRs.

Study Design

Prospective, randomized, open-label, parallel-group, investigator-initiated, international multicenter trial.

Setting & Participants

KTRs aged 18-80 years with a stable graft function (estimated glomerular filtration rate > 20 mL/min/1.73 m²), 3-60 months after transplantation, treated with tacrolimus or cyclosporine A, were eligible for inclusion.

Intervention

Continuation with a CNI-based regimen or switch to belatacept for 12 months.

Outcomes

Comparison of the change in the estimated 7-year risk of major adverse CV events and all-cause mortality, changes in traditional markers of CV health, as well as measures of arterial stiffness.

Results

Among the 105 KTRs randomized, we found no differences between the treatment groups in the predicted risk for major adverse CV events or mortality. Diastolic blood pressure, measured both centrally by using a SphygmoCor device and peripherally, was lower after the belatacept treatment than after the CNI treatment. The mean changes in traditional cardiovascular (CV) risk factors, including kidney transplant function, were otherwise similar in both the treatment groups. The belatacept group had 4 acute rejection episodes; 2 were severe rejections, of which 1 led to graft loss.

Limitations

The heterogeneous baseline estimated glomerular filtration rate and time from transplantation to trial enrollment in the participants. A limited study duration of 1 year.

Conclusions

We found no effects on the calculated CV risk by switching to the belatacept treatment. Participants in the belatacept group had not only lower central and peripheral diastolic blood pressure but also a higher rejection rate.

Funding

The trial has received a financial grant from Bristol-Myers Squibb.

Trial Registration

EudraCT no. 2013-001178-20.

Mild-to-Moderate Kidney Dysfunction and Cardiovascular Disease: Observational and Mendelian Randomization Analyses

BACKGROUND

End-stage renal disease is associated with a high risk of cardiovascular events. It is unknown, however, whether mild-to-moderate kidney dysfunction is causally related to coronary heart disease (CHD) and stroke.

METHODS

Observational analyses were conducted using individual-level data from 4 population data sources (Emerging Risk Factors Collaboration, EPIC-CVD [European Prospective Investigation into Cancer and Nutrition-Cardiovascular Disease Study], Million Veteran Program, and UK Biobank), comprising 648 135 participants with no history of cardiovascular disease or diabetes at baseline, yielding 42 858 and 15 693 incident CHD and stroke events, respectively, during 6.8 million person-years of follow-up. Using a genetic risk score of 218 variants for estimated glomerular filtration rate (eGFR), we conducted Mendelian randomization analyses involving 413 718 participants (25 917 CHD and 8622 strokes) in EPIC-CVD, Million Veteran Program, and UK Biobank.

RESULTS

There were U-shaped observational associations of creatinine-based eGFR with CHD and stroke, with higher risk in participants with eGFR values <60 or >105 mL·min-1·1.73 m-2, compared with those with eGFR between 60 and 105 mL·min-1·1.73 m-2. Mendelian randomization analyses for CHD showed an association among participants with eGFR <60 mL·min-1·1.73 m-2, with a 14% (95% CI, 3%-27%) higher CHD risk per 5 mL·min-1·1.73 m-2 lower genetically predicted eGFR, but not for those with eGFR >105 mL·min-1·1.73 m-2. Results were not materially different after adjustment for factors associated with the eGFR genetic risk score, such as lipoprotein(a), triglycerides, hemoglobin A1c, and blood pressure. Mendelian randomization results for stroke were nonsignificant but broadly similar to those for CHD.

CONCLUSIONS

In people without manifest cardiovascular disease or diabetes, mild-to-moderate kidney dysfunction is causally related to risk of CHD, highlighting the potential value of preventive approaches that preserve and modulate kidney function.

A Consistency Model for Identifying the Effects of n-3 and n-6 Fatty Acids on Lipoproteins in Dialysis Patients

Numerous randomized controlled trials (RCTs) and meta-analyses have assessed the effects of supplemental dietary polyunsaturated fatty acids (PUFAs) on levels of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) and the LDL/HDL ratio in patients receiving renal replacement therapy (RRT). However, results are ambiguous due to mixed reports of various nutrients used in the intervention group. We performed a network meta-analysis of RCTs to assess the effects of PUFAs on lipid profiles in patients undergoing RRT. RCTs performed before November 2021 were gathered from three databases. The means, standard deviations and the number of cases for each arm were independently extracted by two authors to form a network meta-analysis of LDL and HDL levels and the LDL/HDL ratio in a random effects model. Twenty-eight RCTs (n = 2017 subjects) were included in this study. The pooled results revealed that the combination of omega-3 fatty acids (n-3) and omega-6 fatty acids (n-6) produced significantly lower LDL (standardized mean difference (SMD) = −1.43, 95% confidence interval: −2.28 to −0.57) than the placebo. Both n-3 fatty acids (SMD = 0.78) and the combination of n-3 + n-6 (SMD = 1.09) benefited HDL significantly compared with placebo. Moreover, n-3 alone also exhibited a significantly lower LDL/HDL ratio than placebo. Collectively, PUFAs seem to be adequate nutrients for controlling lipoproteins in patients undergoing RRT. Specifically, n-3 + n-6 supplementation improved LDL levels, while n-3 improved HDL levels and the LDL/HDL ratio. However, our data provide limited information on specific dosages of PUFAs to form a concrete recommendation.

Pathological sequelae of long-haul COVID

The world continues to contend with successive waves of coronavirus disease 2019 (COVID-19), fueled by the emergence of viral variants. At the same time, persistent, prolonged and often debilitating sequelae are increasingly recognized in convalescent individuals, named 'post-COVID-19 syndrome' or 'long-haul COVID'. Clinical symptomatology includes fatigue, malaise, dyspnea, defects in memory and concentration and a variety of neuropsychiatric syndromes as the major manifestations, and several organ systems can be involved. The underlying pathophysiological mechanisms are poorly understood at present. This Review details organ-specific sequelae of post-COVID-19 syndromes and examines the underlying pathophysiological mechanisms available so far, elaborating on persistent inflammation, induced autoimmunity and putative viral reservoirs. Finally, we propose diagnostic strategies to better understand this heterogeneous disorder that continues to afflict millions of people worldwide.

Does previous stroke modify the relationship between inflammatory biomarkers and clinical endpoints in CKD patients?

Background

Chronic kidney disease (CKD) is an independent risk factor for stroke. Stroke is also an independent risk factor for worse CKD outcomes and inflammation may contribute to this bidirectional relationship. This study aims to investigate inflammatory biomarkers in patients with non-dialysis CKD (ND-CKD) with and without stroke.

Methods

A propensity matched sample from > 3000 Salford Kidney Study (SKS) patients, differentiated by previous stroke at study recruitment, had stored plasma analyzed for interleukin- 6 (IL-6), Von Willebrand Factor (VWF) and C-reactive protein (CRP). Multivariable cox regression analysis investigated associations between inflammation and death, end-stage renal disease (ESRD) and future non-fatal cardiovascular events (NFCVE).

Results

A total of 157 previous stroke patients were compared against 162 non-stroke patients. There were no significant differences in inflammatory biomarkers between the two groups. Previous stroke was associated with greater mortality risk, hazard ratio (HR) (95% CI) was 1.45 (1.07–1.97). Higher inflammatory biomarker concentrations were independently associated with death but not ESRD or NFCVE in the total population. For each 1 standard deviation (SD) increase in log IL-6, VWF and CRP, the HR for all-cause mortality were 1.35 (1.10–1.70), 1.26 (1.05–1.51) and 1.34 (1.12–1.61), respectively. CRP retained its independent association (HR 1.47 (1.15–1.87)) with death in the stroke population.

Conclusion

Previous stroke is an important determinant of mortality. However, the adverse combination of stroke and ND-CKD does not seem to be driven by higher levels of inflammation detected after the stroke event. Biomarkers of inflammation were associated with worse outcome in both stroke and non-stroke ND-CKD patients.

Trial registration

15/NW/0818.

Prevalence of drug-resistant microbes in sepsis cases of catheter and fistula based haemodialysis

Background

Chronic stage renal disease is a severe disease of the kidney which affects people globally. According to the global burden of diseases in 2010, this disease has caused more deaths worldwide and due to the high death rate, the ESRD (end-stage renal disease) is now ranked up from 27th to 18th range in the list.

Methodology

Dialysis samples were collected from the Haripur city and surrounding areas. Samples were inoculated on different selective media for bacterial growth. In addition, different biochemical tests were also performed for identification, where as the resistance genes were identified through a polymerase chain reaction.

Result

Out of the total 100 dialysis patient’s blood samples, only 17 showed the presence of gram-positive bacteria i.e., Staphylococcus aureus while two shown the presence of gram-negative bacteria i.e., Klebsiella pneumoniaeee and Pseudomonas aeruginosa. While in molecular identification two antibiotic resistance genes muc and mecA belong to the staphylococcus strain shown their presence.

Conclusion

A high infection rate has been observed in fistula-based hemodialysis (17(77.27%)) as compares to catheter-based hemodialysis (5(22.3%) with no significant difference of incidence between the groups (p > 0.05).

Myocardial changes on 3T cardiovascular magnetic resonance imaging in response to haemodialysis with fluid removal

BACKGROUND

Mapping of left ventricular (LV) native T1 is a promising non-invasive, non-contrast imaging biomarker. Native myocardial T1 times are prolonged in patients requiring dialysis, but there are concerns that the dialysis process and fluctuating fluid status may confound results in this population. We aimed to assess the changes in cardiac parameters on 3T cardiovascular magnetic resonance (CMR) before and after haemodialysis, with a specific focus on native T1 mapping.

METHODS

This is a single centre, prospective observational study in which maintenance haemodialysis patients underwent CMR before and after dialysis (both scans within 24 h). Weight measurement, bio-impedance body composition monitoring, haemodialysis details and fluid intake were recorded. CMR protocol included cine imaging and mapping native T1 and T2.

RESULTS

Twenty-six participants (16 male, 65 ± 9 years) were included in the analysis. The median net ultrafiltration volume on dialysis was 2.3 L (IQR 1.8, 2.5), resulting in a median weight reduction at post-dialysis scan of 1.35 kg (IQR 1.0, 1.9), with a median reduction in over-hydration (as measured by bioimpedance) of 0.75 L (IQR 0.5, 1.4). Significant reductions were observed in LV end-diastolic volume (- 25 ml, p = 0.002), LV stroke volume (- 13 ml, p = 0.007), global T1 (21 ms, p = 0.02), global T2 (- 1.2 ms, p = 0.02) following dialysis. There was no change in LV mass (p = 0.35), LV ejection fraction (p = 0.13) or global longitudinal strain (p = 0.22). On linear regression there was no association between baseline over-hydration (as defined by bioimpedance) and global native T1 or global T2, nor was there an association between the change in over-hydration and the change in these parameters.

CONCLUSIONS

Acute changes in cardiac volumes and myocardial native T1 are detectable on 3T CMR following haemodialysis with fluid removal. The reduction in global T1 suggests that the abnormal native T1 observed in patients on haemodialysis is not entirely due to myocardial fibrosis.

The association between fast-food consumption with cardiovascular diseases risk factors and kidney function in patients with diabetic nephropathy

Introduction: Fast food consumption (FFC) has been raised as a risk factor for cardiometabolic outcomes and renal function disorders. The present study aimed to investigate the association between FFC and cardiovascular disease (CVD) risk factors and renal function among patients with diabetic nephropathy (DN).

Methods: This cross-sectional study was conducted among 397 randomly enrolled patients with DN. A validated 168 food items food frequency questionnaire was used for measuring FFC. Weight, waist,height, fasting blood sugar (FBS), hemoglobin A1C (HbA1C), serum creatinine, blood urea nitrogen(BUN), hs-CRP, systolic blood pressure(SBP), diastolic blood pressure (DBP), and lipid profile concentrations were measured. Generalized linear model analysis of covariance was used to compare means of BP, biochemical and anthropometric factors across tertiles of FFC adjusted for potential confounders.

Results: The mean weekly intakes of fast food were 130 ± 60 grams. Patients in the highest compared to the lowest tertiles of FFC were more likely to be overweight and obese, had higher levels of creatinine, SBP, and DBP in the unadjusted model (P < 0.05). In the adjusted models, DN patients in the highest vs lowest tertiles of FFC had higher levels of SBP and DBP (P = < 0.001).

Conclusion: Higher consumption of fast food is associated with higher levels of both systolic and diastolic blood pressure in DN patients. The present study observed no significant differences between the highest versus the lowest tertiles of FFC for waist, FBS, HbA1C, serum creatinine, BUN, hs-CRP, and lipid profile concentrations.

Direct Evidence of Endothelial Dysfunction and Glycocalyx Loss in Dermal Biopsies of Patients With Chronic Kidney Disease and Their Association With Markers of Volume Overload

Cardiovascular morbidity is a major problem in patients with chronic kidney disease (CKD) and endothelial dysfunction (ED) is involved in its development. The luminal side of the vascular endothelium is covered by a protective endothelial glycocalyx (eGC) and indirect evidence indicates eGC loss in CKD patients. We aimed to investigate potential eGC loss and ED in skin biopsies of CKD patients and their association with inflammation and volume overload. During living kidney transplantation procedure, abdominal skin biopsies were taken from 11 patients with chronic kidney disease stage 5 of whom 4 were treated with hemodialysis and 7 did not receive dialysis treatment. Nine healthy kidney donors served as controls. Biopsies were stained and quantified for the eGC marker Ulex europaeus agglutinin-1 (UEA1) and the endothelial markers vascular endothelial growth factor-2 (VEGFR2) and von Willebrand factor (vWF) after double staining and normalization for the pan-endothelial marker cluster of differentiation 31. We also studied associations between quantified log-transformed dermal endothelial markers and plasma markers of inflammation and hydration status. Compared to healthy subjects, there was severe loss of the eGC marker UEA1 (P < 0.01) while VEGFR2 was increased in CKD patients, especially in those on dialysis (P = 0.01). For vWF, results were comparable between CKD patients and controls. Skin water content was identical in the three groups, which excluded dermal edema as an underlying cause in patients with CKD. The dermal eGC/ED markers UEA1, VEGFR2, and vWF all associated with plasma levels of NT-proBNP and sodium (all R² > 0.29 and P < 0.01), except for vWF that only associated with plasma NT-proBNP. This study is the first to show direct histopathological evidence of dermal glycocalyx loss and ED in patients with CKD. In line with previous research, our results show that ED associates with markers of volume overload arguing for strict volume control in CKD patients.

The relationship between calcification inhibitor levels in chronic kidney disease and the development of atherosclerosis

Aim

We aimed to investigate the factors affecting the development of atherosclerosis and the role of calcification inhibitors fetuin-A, matrix-Gla protein (MGP), osteoprotegerin (OPG) in atherosclerosis progress.

Material and methods

The study was planned to investigate the relationship of serum OPG, MGP and fetuin-A levels with the development of atherosclerosis in the stage 2–3–4–5 chronic kidney disease (CKD) patients who did not require dialysis treatment.

Results

32 (17 female, 15 male) healthy individuals and 92 (49 females, 43 males) CKD patients were included. The mean carotid intima-media thickness (CIMT), C-reactive protein (CRP), fetuin-A, OPG and MGP of the two groups were compared statistically. In CKD patients, age, body mass index (BMI), CRP, triglyceride, urea, systolic blood pressure (SBP), fasting blood sugar have a positive linear relationship, fetuin-A, OPG, GFR have a negative linear relationship with CIMT. The mean CIMT, right CIMT, left CIMT, blood urea, CRP, urinary albumin excretion creatinine and age show a negative linear relationship with fetuin-A.

Conclusion

Fetuin-A levels begin to decline from the early stages of CKD and are significantly lower in patients with atherosclerosis as expressed with CIMT. This suggests that fetuin-A may be used as an early marker in CKD for increased cardiovascular risk. Early recognition of these risk factors is important and large-scale studies on vascular calcification inhibitors are needed.

Non-high-density lipoprotein cholesterol and mortality among peritoneal dialysis patients

BACKGROUND

The association between non-high-density lipoprotein cholesterol (non-HDL-C) and mortality in patients undergoing peritoneal dialysis (PD) is unclear.

OBJECTIVE

The aim of this study was to evaluate the association of non-HDL-C with cardiovascular (CV) and all-cause mortality in PD patients.

METHODS

We conducted a prospective cohort study. A total of 1,616 incident PD patients from a single PD center in South China were followed for a median of 47.6 months. The independent association of non-HDL-C with CV and all-cause mortality was evaluated by a Cox regression analysis.

RESULTS

During the follow-up period, 508 (31.4%) patients died, of which 249 (49.0%) were due to CV events. Atherosclerotic CV mortality accounted for 59.8% of CV mortality. In multivariable models, for 1-SD increase in non-HDL-C level, the hazard ratios (HRs) for CV and all-cause mortality were 1.52  [95% confidence interval (CI), 1.32-1.75; P < 0.001)] and 1.24 (95% CI, 1.12-1.39; P < 0.001), respectively. Furthermore, non-HDL-C was positively associated with atherosclerotic CV mortality (HR, 1.29; 95% CI, 1.09-1.52; P = 0.004) but not associated with nonatherosclerotic CV mortality (HR, 0.79; 95% CI, 0.59-1.05; P = 0.108). The quartile analyses showed a similar pattern to the continuous variable analyses of non-HDL-C levels for CV and all-cause mortality but did not demonstrate statistical significance for atherosclerotic or nonatherosclerotic CV mortality.

CONCLUSION

An elevated non-HDL-C level was independently associated with an increased risk of CV mortality, especially atherosclerotic CV mortality, and all-cause mortality in incident PD patients.

Homocysteine-Lowering Interventions in Chronic Kidney Disease

The incidence of cardiovascular events and mortality is higher in patients with chronic kidney disease (CKD) compared to the general population. Homocysteine (Hcy) appears to be an independent risk factor for cardiovascular diseases in general populations and patients with CKD. Further, hyperhomocysteinemia can cause endothelial damage and increase the activity and production of coagulation factors, and its prevalence among patients with end-stage renal disease is approximately 85%-100%. Most treatments, which lower Hcy levels and have been considered in previous studies, include folic acid, B vitamins, omega-3 fatty acids, and N-acetylcysteine. However, the effect of therapies that can decrease Hcy levels and thus cardiovascular events in these patients is still unclear. The results are conflicting and require further investigation. To guide treatment decisions and improve patient outcomes, multiple databases were searched, including Web of Science, PubMed, and Medline to summarize the available evidence (i.e., clinical trial and meta-analyses) on Hcy-lowering interventions and cardiovascular events.

Oxidative stress, inflammation, and peritoneal dialysis: A molecular biology approach

The key role of oxidative stress (OxSt) and inflammation for the induction of cardiovascular disease, the leading cause of excess morbidity/mortality in chronic kidney disease and dialysis patients, is known and both the activations of NADPH oxidase and RhoA/Rho kinase (ROCK) pathway are pivotal for their effects. While specific hemodialysis procedures, such as hemodiafiltration with on‐line reinfusion of ultrafiltrate and/or the use of vitamin E‐coated dialyzers, are beneficial for OxSt and inflammation, studies in peritoneal dialysis (PD) are instead scarce and results seem not favorable. In nine patients under PD OxSt in terms of mononuclear cell protein level of p22^phox (Western blot), subunit of NADPH oxidase, essential for the generation of OxSt, and MYPT‐1 phosphorylation state (Western blot), a marker of ROCK activity, have been measured at the beginning and after 3 and 6 months of PD. Blood levels of interleukin 6 (IL‐6), ferritin, and albumin have been considered for evaluating the inflammatory state. p22^phox protein expression, MYPT‐1‐phosphorylation, and ferritin level were increased both at baseline vs healthy subjects (P = .02, P < .0001, P = .004, respectively) and vs baseline after 3 and 6 months of peritoneal dialysis (P = .007, P < .001, P = .004, respectively). Albumin was lower after 6 months of PD (P = .0014). IL‐6 was increased at baseline vs reference values and remained unchanged at 3 and 6 months. OxSt and inflammation increase during PD confirming via molecular biology approach a report at biochemical level. To improve OxSt state in PD, a multitarget approach is necessary. It might include the use of more physiologic pH, low glucose degradation products, low lactate and iso‐osmolar PD solutions, patients’ strict glycemic control, optimal volume management, and antioxidant administration, such as N‐acetylcysteine.

Effects of Myo-inositol Hexaphosphate (SNF472) on Bone Mineral Density in Patients Receiving Hemodialysis: An Analysis of the Randomized, Placebo-Controlled CaLIPSO Study

BACKGROUND AND OBJECTIVES

In the CaLIPSO study, intravenous administration of SNF472 (300 or 600 mg) during hemodialysis significantly attenuated progression of coronary artery and aortic valve calcification. SNF472 selectively inhibits formation of hydroxyapatite, the final step in cardiovascular calcification. Because bone mineral is predominantly hydroxyapatite, we assessed changes in bone mineral density in CaLIPSO.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients with coronary artery calcification at screening (Agatston score of 100-3500 U) were randomized 1:1:1 to receive placebo, 300 mg SNF472, or 600 mg SNF472 as an intravenous infusion during hemodialysis three times weekly for 52 weeks. Dual-energy x-ray absorptiometry (DXA) scans were obtained at baseline (screening) and end of treatment, and between-group changes from baseline were compared using analysis of covariance.

RESULTS

Among 274 randomized patients, 202 had evaluable DXA scans at baseline and postrandomization (the DXA-modified intention-to-treat population). Mean (95% confidence interval) changes in total-hip bone mineral density from baseline to week 52 were -1.5% (-2.7% to -0.3%), -1.5% (-2.7% to -0.4%), and -2.5% (-3.8% to -1.2%) in the placebo, 300 mg SNF472, and 600 mg SNF472 groups, respectively. Mean (95% confidence interval) changes in femoral-neck bone mineral density from baseline to week 52 were -0.3% (-1.6% to 1.0%), -1.0% (-2.3% to 0.2%), and -2.6% (-4.0% to -1.3%), respectively. Regression analyses showed no correlation between change in coronary artery calcium volume and change in bone mineral density at either location. Changes in serum alkaline phosphatase, calcium, magnesium, phosphate, and intact parathyroid hormone levels were similar across treatment groups. Clinical fracture events were reported for four of 90, three of 92, and six of 91 patients in the placebo, 300 mg SNF472, and 600 mg SNF472 groups, respectively.

CONCLUSIONS

Bone mineral density decreased modestly in all groups over 1 year. In the 600 mg SNF472 group, the reduction appeared more pronounced. Reported fractures were infrequent in all groups.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Effect of SNF472 on Progression of Cardiovascular Calcification in End-Stage-Renal-Disease (ESRD) Patients on Hemodialysis (HD), NCT02966028.

Serum Raman spectroscopy combined with multiple algorithms for diagnosing thyroid dysfunction and chronic renal failure

In this study, 60 samples taken from patients with thyroid dysfunction, 40 samples taken from patients with chronic renal failure (CRF) and 60 samples taken from healthy people were classified. We used partial least squares (PLS) to extract features to reduce the dimension of the spectral data to discriminate among the different samples. The Decision Trees (DT), Extreme Learning Machine (ELM), Probabilistic Neural Network (PNN), Back Propagation Neural Network (BPNN) and Learning Vector Quantization (LVQ) algorithms were used to build classification models and compare the results. The PLS-PNN algorithm distinguished between patients with thyroid dysfunction and patients with chronic renal failure with up to a 96.67 % accuracy rate, the PLS-BP algorithm distinguished between patients with chronic renal failure and healthy people with up to a 98.33 % accuracy rate, and the PLS-PNN algorithm and the PLS-DT algorithm distinguished between healthy people and patients with chronic renal failure with up to a 100 % accuracy rate. The results showed that serum Raman spectroscopy can be used in conjunction with classification algorithms to rapidly and accurately diagnose and distinguish between thyroid dysfunction and chronic renal failure.

Optimal timing of coronary angiograms for patients with chronic kidney disease: association between the duration of kidney dysfunction and SYNTAX scores

Background

Chronic kidney disease (CKD) is associated with an increased risk of the progression of coronary artery disease (CAD). However, there are few data on the relationship between CAD severity and the duration of CKD. This study assessed the predictive value of the duration of kidney dysfunction in CKD patients with CAD severity.

Methods

In 145 patients (63.4% male, n = 92; mean age, 68.8 ± 12.8 years) with CKD, severity of CAD was assessed by coronary angiography and quantified by SYNTAX scores, and duration of kidney dysfunction was either assessed by checking historical biochemical parameters of individuals or was based on enquiries.

Results

Patients with high SYNTAX scores (≥ 22) had a greater prevalence of cardiovascular risk factors including age, gender, history of heart failure and smoking. In CKD patients, SYNTAX scores were positively correlated to duration of CKD and serum uric acid (UA), and negatively correlated to high-density lipoprotein-cholesterol (HDL-C) and ApoA1 levels. Univariate binary logistic regression and multivariate logistic analyses showed that SYNTAX scores correlated significantly with CKD duration, UA, and HDL-C. Receiver-operating characteristic analysis was used to explore a time point when coronary angiography application was economical and effective and yielded a Youden index of 6.5 years.

Conclusions

Together, our results demonstrated that the duration of kidney dysfunction was an independent correlate of the severity of CAD in patients with CKD. Our findings suggest that coronary angiography should be considered for CKD patients with renal insufficiency having lasted for more than 6.5 years.

Quantification of extracellular volume fraction by cardiac computed tomography for noninvasive assessment of myocardial fibrosis in hemodialysis patients

Extent of myocardial fibrosis in hemodialysis patients has been associated with poor prognosis. Myocardial extracellular volume (ECV) quantification using contrast enhanced cardiac computed tomography (CT) is a novel method to determine extent of myocardial fibrosis. Cardiac CT-based myocardial ECV in hemodialysis patients with those of propensity-matched non-hemodialysis control subjects were compared. Twenty hemodialysis patients (mean age, 67.4 ± 9.6 years; 80% male) and 20 propensity-matched non-hemodialysis controls (mean age, 66.3 ± 9.1 years; 85% male) who underwent comprehensive cardiac CT consisted of calcium scoring, coronary CT angiography, stress perfusion CT and delayed enhancement CT were evaluated. Myocardial ECV was significantly greater in the hemodialysis group than in the control group (33.8 ± 4.7% versus 26.6 ± 2.9%; P < 0.0001). In the hemodialysis group, modest correlation was evident between myocardial ECV and left atrial volume index (r = 0.54; P = 0.01), while there was no correlation between myocardial ECV and other cardiac parameters including left ventricular mass index and severity of myocardial ischemia. Cardiac CT-based myocardial ECV may offer a potential imaging biomarker for myocardial fibrosis in HD patients.

A scoring system for predicting individual treatment effects of statins in type 2 diabetes patients on haemodialysis

AIMS

Haemodialysis patients have high cardiovascular disease risk. Although statins reduce this risk in chronic kidney disease, randomised trials in haemodialysis patients show no benefit. Post-hoc analyses of the German Diabetes Dialysis (4D) study identified patient-specific markers associated with heterogeneous treatment effects. We combined these markers to develop a score for predicting individual effects of statins in these patients.

METHODS AND RESULTS

We used data from the 4D study, enrolling 1255 haemodialysis patients with type 2 diabetes mellitus, randomised to atorvastatin or placebo and followed for a composite cardiovascular endpoint. We calculated two scores: score 1 based on all 23 predictive markers and score 2 based on 17 clinically accessible markers. Groups stratified by score 1 showed differential treatment effects: for score <26 (458 patients; 36%), the hazard ratio (95% confidence interval) was 1.54 (1.16-2.03), suggesting harm; for 26-31 (331 patients; 26%), it was 1.03 (0.72-1.48), suggesting a neutral effect; and for >31 (466 patients; 38%), it was 0.43 (0.30-0.60), suggesting a benefit. Statins also significantly reduced all-cause mortality in the benefit group. Stratification by score 2 yielded similar results but a smaller group gaining benefit (360 patients).

CONCLUSION

Statin effects in haemodialysis patients can be predicted by markers associated with plausible relevant mechanisms including cholesterol metabolism, atherosclerosis, protein energy wasting, or competing risks. In clinical practice, the score could aid in risk stratification, not only to select patients who benefit from statins but also to identify those whom treatment could harm.

Biological variation of cardiac troponins in chronic kidney disease

Background

Patients with chronic kidney disease often have increased plasma cardiac troponin concentration in the absence of myocardial infarction. Incidence of myocardial infarction is high in this population, and diagnosis, particularly of non ST-segment elevation myocardial infarction (NSTEMI), is challenging. Knowledge of biological variation aids understanding of serial cardiac troponin measurements and could improve interpretation in clinical practice. The National Academy of Clinical Biochemistry (NACB) recommended the use of a 20% reference change value in patients with kidney failure. The aim of this study was to calculate the biological variation of cardiac troponin I and cardiac troponin T in patients with moderate chronic kidney disease (glomerular filtration rate [GFR] 30–59 mL/min/1.73 m2).

Methods and results

Plasma samples were obtained from 20 patients (median GFR 43.0 mL/min/1.73 m2) once a week for four consecutive weeks. Cardiac troponin I (Abbott ARCHITECT® i2000SR, median 4.3 ng/L, upper 99th percentile of reference population 26.2 ng/L) and cardiac troponin T (Roche Cobas® e601, median 11.8 ng/L, upper 99th percentile of reference population 14 ng/L) were measured in duplicate using high-sensitivity assays. After outlier removal and log transformation, 18 patients’ data were subject to ANOVA, and within-subject (CVI), between-subject (CVG) and analytical (CVA) variation calculated. Variation for cardiac troponin I was 15.0%, 105.6%, 8.3%, respectively, and for cardiac troponin T 7.4%, 78.4%, 3.1%, respectively. Reference change values for increasing and decreasing troponin concentrations were +60%/–38% for cardiac troponin I and +25%/–20% for cardiac troponin T.

Conclusions

The observed reference change value for cardiac troponin T is broadly compatible with the NACB recommendation, but for cardiac troponin I, larger changes are required to define significant change. The incorporation of separate RCVs for cardiac troponin I and cardiac troponin T, and separate RCVs for rising and falling concentrations of cardiac troponin, should be considered when developing guidance for interpretation of sequential cardiac troponin measurements.

Lack of Isoprene Overproduction during Peritoneal Dialysis

Objective

Isoprene is the constitutive unit of isoprenoid lipids and sterols. However, it is also a potential toxic and carcinogenic agent. Recent findings of a marked and prolonged isoprene overproduction induced by hemodialysis sessions raises the question of isoprene behavior in patients on peritoneal dialysis.

Design

A study with repeated measures per patient and healthy control.

Setting

Nephrology and Dialysis Unit and Perugia University Medical School.

Patients

Sixteen consecutive patients on regular continuous ambulatory peritoneal dialysis (CAPD) were evaluated. Endogenous isoprene was analyzed using gas chromatographic assay of breath isoprene, collected at set times before and after dialysis fluid exchange.

Results

No significant variations were found in breath isoprene concentrations in the different samples from each patient, and levels were almost stable within the normal range of healthy controls.

Conclusion

These results show that CAPD, unlike hemodialysis, has little or no effect on isoprene and isoprenoid-related lipid turnover. This lack of increased endogenous isoprene synthesis, in addition to being a distinctive metabolic feature of CAPD, could have important pathophysiological and clinical implications.

Effective Homocysteine-Lowering Vitamin B Treatment in Peritoneal Dialysis Patients

Background

Hyperhomocysteinemia, a risk factor for atherosclerosis, is frequently detected in patients with renal failure. Vitamin B supplementation reduces but rarely normalizes homocysteine (Hcy) levels in hemodialysis patients. There are no data about the effects of vitamin B therapy on Hcy levels in patients on peritoneal dialysis (PD).

Aims

We performed this trial both to observe baseline plasma Hcy levels in PD patients and to assess the effects of vitamin B therapy on Hcy levels in continuous ambulatory PD patients.

Methods

We conducted a 6-month prospective study of the effects of vitamin B therapy on plasma Hcy levels. Biochemical analyses were obtained at baseline and after every phase of treatment with folic acid, folic acid plus vitamin B12, and folic acid plus vitamin B12plus vitamin B6. Eighteen of the 25 enrolled patients finished the study.

Results

Hyperhomocysteinemia was present in 83% of PD patients. We detected a trend toward a significant inverse relationship between baseline Hcy and folate levels. There were no significant correlations between baseline Hcy and vitamin B12, peritoneal membrane permeability, dialytic efficiency, or computed peritoneal Hcy clearance. We obtained an effective decrease in mean Hcy concentration from 20 to 14.8 μmol/L after folic acid and vitamin B12treatment. We observed a further reduction in mean Hcy level to 12.8 μmol/L using the triple therapy; 72% of patients normalized their Hcy value.

Conclusions

High doses of folic acid, vitamin B6, and vitamin B12normalize Hcy values in the majority of PD patients. This treatment may be important in reducing cardiovascular morbidity and mortality.

Effect of statin on life prognosis in Japanese patients undergoing hemodialysis

The effect of statin on hemodialysis patients is controversial. Although previous large-scale studies did not clarify its effect in this population, recent studies suggest that statins could be useful in reducing the risk of cardiovascular events and all-cause mortality in specific groups of patients undergoing hemodialysis. The aforementioned large-scale studies included a small percentage of Asians, and few studies have investigated the effects of statins in Asians undergoing hemodialysis. Thus, we investigated the benefits of statins in patients undergoing maintenance hemodialysis at a single center in Japan. We obtained demographic, clinical, and hemodialysis data of all patients who underwent maintenance hemodialysis at the Nagasaki Renal Center between July 2011 and June 2012. Patients were followed-up until June 2018. We studied 339 patients, of which 51 (15.0%) were prescribed pitavastatin. The mean observation period was 4.1±2.3 years, 43% were women, and the median hemodialysis vintage at baseline was 4.7 years. During the follow-up, 198 patients (58%) died, of which 22 (43%) were prescribed pitavastatin and 176 (61%) were not prescribed any statins. After propensity score matching based on age, sex, dialysis vintage, dialysis time, diabetes mellitus, ischemic heart disease, dry weight, left ventricular ejection fraction, and serum albumin, an intergroup comparison between those who received statins and those who did not (44 patients in each group) showed significant differences in survival rate based on the log-rank test (P<0.05). Although the causes of death did not differ significantly between groups, deaths due to cardiovascular events, infections, and cancer were fewer in the group prescribed statins. Our results suggest that statins may reduce mortality in Japanese patients undergoing maintenance hemodialysis. Although potential residual confounders exist, statins may have an influence on the reduction in the incidence of cardiovascular events, infections, and cancer. Nevertheless, further studies are required to prove this hypothesis.

Serum 8-hydroxydeoxyguanosine, a marker of oxidative DNA damage, is associated with mortality independent of inflammation in chronic kidney disease

BACKGROUND

Oxidative stress and low-grade systemic inflammation are common interrelated sequelae of chronic kidney disease (CKD) that associate with mortality. We investigated the association of serum 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, with mortality in CKD individuals and analyzed whether inflammation modifies the association.

METHODS

In 376 individuals with a wide range of estimated glomerular filtration rate (eGFR); >60 ml/min (n = 53), 15-60 ml/min (n = 60) and <15 ml/min (n = 263), cut-off values of serum 8-OHdG, high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and tumor necrosis factor (TNF) as predictors of mortality were determined by ROC curves. We analyzed associations of 8-OHdG with inflammation markers and the overlapping effect of hsCRP, IL-6 and TNF on the association between 8-OHdG and all-cause mortality by multivariate generalized linear models.

RESULTS

In separate individual exposure analyses, higher 8-OHdG, hsCRP, and IL-6 (but not TNF) were each independently associated with increased risk of death in multivariate models adjusted for age, sex, diabetes mellitus, cardiovascular disease, protein-energy wasting, cohort calendar year, blood sample storage time and eGFR. For 8-OHdG, the multivariate relative risk ratio, RR_8-OHdG (95% confidence interval) 1.17 (1.08-1.26), remained essentially unchanged when adjusting also for inflammation in three separate models including: hsCRP, RR_8-OHdG = 1.15 (1.06-1.25); IL-6, RR_8-OHdG = 1.15 (1.07-1.25); and TNF, RR_8-OHdG = 1.16 (1.07-1.26).

CONCLUSIONS

Serum 8-OHdG, a biomarker of oxidative DNA damage, is associated with increased all-cause mortality risk in individuals with a wide range of eGFR and this association is independent of inflammation.

Cardiovascular and renal outcomes following percutaneous coronary intervention in a population with renal disease: a case-control study

BACKGROUND

Patients with renal disease are less likely to undergo percutaneous coronary intervention (PCI) due to concerns about poor outcomes.

AIM

We describe outcomes following PCI in individuals with chronic kidney disease (CKD), as compared with matched controls with comparable CKD who did not undergo PCI. We also identified factors predictive of poor outcomes following PCI amongst patients with CKD.

DESIGN

Retrospective observational case-control study.

METHODS

Cases were individuals with CKD (stages 1-5) undergoing PCI between 2008 and 2014. Controls were age, gender and creatinine-matched individuals not requiring PCI. We compared mortality between groups using Kaplan-Meier curves and Cox regression modelling. We assessed changes in serum creatinine using Wilcoxon Rank testing. We explored the relationship between biochemical and haematological measures (baseline creatinine, calcium, phosphate, calcium-phosphate product, parathyroid hormone, white cell count, haemoglobin, platelet count, c-reactive protein and total cholesterol) and post-PCI mortality, using logistic regression.

RESULTS

We identified 144 cases and 144 controls. Mortality was significantly lower amongst cases compared with controls [hazard ratio 0.46 (95% confidence intervals 0.31, 0.69)]. PCI did not result in a significant change in renal function (P=0.52). Amongst cases, serum creatinine and calcium-phosphate product were predictors of mortality following PCI.

CONCLUSION

Cases undergoing PCI had lower mortality, and PCI was not associated with accelerated CKD progression. On this data, PCI should not be deferred as a treatment option in patients with CKD. Serum creatinine and calcium-phosphate product predict mortality following PCI in this cohort, and may be useful in risk-stratifying patients with CKD being considered for PCI.

Lipid management in patients with chronic kidney disease

An increased risk of cardiovascular disease, independent of conventional risk factors, is present even at minor levels of renal impairment and is highest in patients with end-stage renal disease (ESRD) requiring dialysis. Renal dysfunction changes the level, composition and quality of blood lipids in favour of a more atherogenic profile. Patients with advanced chronic kidney disease (CKD) or ESRD have a characteristic lipid pattern of hypertriglyceridaemia and low HDL cholesterol levels but normal LDL cholesterol levels. In the general population, a clear relationship exists between LDL cholesterol and major atherosclerotic events. However, in patients with ESRD, LDL cholesterol shows a negative association with these outcomes at below average LDL cholesterol levels and a flat or weakly positive association with mortality at higher LDL cholesterol levels. Overall, the available data suggest that lowering of LDL cholesterol is beneficial for prevention of major atherosclerotic events in patients with CKD and in kidney transplant recipients but is not beneficial in patients requiring dialysis. The 2013 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Lipid Management in CKD provides simple recommendations for the management of dyslipidaemia in patients with CKD and ESRD. However, emerging data and novel lipid-lowering therapies warrant some reappraisal of these recommendations.

Cardiovascular risk in renal transplant recipients

Successful kidney transplantation offers patients with end-stage renal disease the greatest likelihood of survival. However, cardiovascular disease poses a major threat to both graft and patient survival in this cohort. Transplant recipients are unique in their accumulation of a wide range of traditional and non-traditional cardiovascular risk factors. Hypertension, diabetes, dyslipidaemia and obesity are highly prevalent in patients with end-stage renal disease. These risk factors persist following transplantation and are often exacerbated by the drugs used for immunosuppression in organ transplantation. Additional transplant-specific factors such as poor graft function and proteinuria are also associated with increased cardiovascular risk. However, these transplant-related factors remain unaccounted for in current cardiovascular risk prediction models, making it challenging to identify transplant recipients with highest risk. With few interventional trials in this area specific to transplant recipients, strategies to reduce cardiovascular risk are largely extrapolated from other populations. Aggressive management of traditional cardiovascular risk factors remains the cornerstone of prevention, though there is also a potential role for selecting immunosuppression regimens to minimise additional cardiovascular injury.

Protein C and protein S deficiencies may be related to survival among hemodialysis patients

Background

Thrombophilia due to protein C (PC) and protein S (PS) deficiencies is highly prevalent among patients with stage 5 chronic kidney disease and is reported to arise due to extracorporeal circulation during hemodialysis (HD). This study aimed to evaluate the relationship between HD treatment and thrombophilia.

Methods

A total of 114 Japanese patients on maintenance HD (62 men, 52 women) were followed during 2008–2011. Their survival rates were compared against the duration of HD. Prior to each HD, coagulation/fibrinolysis parameters and PC and PS activities were measured using standard techniques. The patients were divided into two groups: Group 1, with PC and/or PS deficiencies (n = 32), and Group 2, without PC and PS deficiencies (n = 82). The influence of such deficiencies and duration of dialysis on survival was examined. Time-to-event analysis was applied using Kaplan-Meier estimates, and the log-rank test was proposed to test the equivalence of relative survival data. Hazard ratios and 95% confidence intervals (CI) were calculated.

Results

Of the 114 patients, 37 died (Group 1, 22; Group 2, 15). The hazard ratio (95% CI) was higher (p = 0.004) in Group 1 than Group 2. Gene analyses of PC and PS were performed in 14 patients from Group 1. No mutations in either protein were observed. We analyzed the causes of death in both groups; however, the estimated thrombophilia-related incidence of death could not be determined due to small sample size of HD patients.

Conclusions

Our results suggest that PC and PS deficiencies may be related to survival in HD patients. However, this finding warrants additional research.

Transplantation and diabetes (Transdiab): a pilot randomised controlled trial of metformin in impaired glucose tolerance after kidney transplantation

BACKGROUND

Post transplantation diabetes mellitus (PTDM) is a common and serious complication after renal transplantation with significant morbidity and mortality. Metformin has proven benefits in the general population and might be advantageous in the prevention and management of PTDM.

METHODS

Transplantation and Diabetes (Transdiab) is a single-centre, unblinded, pilot randomised controlled trial assessing the feasibility, tolerability and efficacy of metformin after renal transplantation in patients with impaired glucose tolerance (IGT). Participants had an oral glucose tolerance test (OGTT) in the 4-12 weeks post-transplantation; those with IGT were randomised to standard care or standard care and metformin 500 mg twice daily and followed up for 12 months.

RESULTS

Seventy eight patients had an OGTT over 24 months, 25 of them had IGT, of those, 19 patients were randomised, giving a feasibility of recruitment of 24.4%. Ten patients were randomised to metformin and 9 patients to standard care. Tolerability and efficacy was similar between the 2 groups with no serious adverse events. There was no difference in secondary outcomes relating to the metabolic profile.

CONCLUSIONS

The use of metformin post renal transplantation appeared feasible and safe. Larger randomised controlled trials (RCTs) are needed to establish and confirm the efficacy and safety of metformin post renal transplantation.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12614001171606 . Date of registration 7/11/2014.

Kidney transplantation is associated with reduced myocardial fibrosis. A cardiovascular magnetic resonance study with native T1 mapping

BACKGROUND

The measurement of native T1 through cardiovascular magnetic resonance (CMR) is a noninvasive method of assessing myocardial fibrosis without gadolinium contrast. No studies so far have evaluated native T1 after renal transplantation. The primary aim of the current study is to assess changes in the myocardium native T1 6 months after renal transplantation.

METHODS

We prospectively evaluated 44 renal transplant patients with 3 T CMR exams: baseline at the beginning of transplantation and at 6 months after transplantation.

RESULTS

The native T1 time was measured in the midventricular septum and decreased significantly from 1331 ± 52 ms at the baseline to 1298 ± 42 ms 6 months after transplantation (p = 0.001). The patients were split into two groups through a two-step cluster algorithm: In cluster-1 (n = 30) the left ventricular (LV) mass index and the prevalence of diabetes were lower. In cluster-2 (n = 14) the LV mass index and diabetes prevalence were higher. Decrease in native T1 values was significant only in the patients in cluster-1 (p = 0.001).

CONCLUSIONS

The native myocardial T1 time decreased significantly 6 months after renal transplant, which may be associated with the regression of the reactive fibrosis. The patients with greater baseline LV mass index and the diabetic group did not reach a significant decrease in T1.

Dysfunctional high-density lipoprotein activates toll-like receptors via serum amyloid A in vascular smooth muscle cells

Serum amyloid A (SAA) is an uremic toxin and acute phase protein. It accumulates under inflammatory conditions associated with high cardiovascular morbidity and mortality in patients with sepsis or end-stage renal disease (ESRD). SAA is an apolipoprotein of the high-density lipoprotein (HDL). SAA accumulation turns HDL from an anti-inflammatory to a pro-inflammatory particle. SAA activates monocyte chemoattractant protein-1 (MCP-1) in vascular smooth muscle cells. However, the SAA receptor-mediated signaling pathway in vascular cells is poorly understood. Therefore, the SAA-mediated signaling pathway for MCP-1 production was investigated in this study. The SAA-induced MCP-1 production is dependent on the activation of TLR2 and TLR4 as determined by studies with specific receptor antagonists and agonists or siRNA approach. Experiments were confirmed in tissues from TLR2 knockout, TLR4 deficient and TLR2 knock-out/TLR4 deficient mice. The intracellular signaling pathway is IκBα and subsequently NFκB dependent. The MCP-1 production induced by SAA-enriched HDL and HDL isolated from septic patients with high SAA content is also TLR2 and TLR4 dependent. Taken together, the TLR2 and TLR4 receptors are functional SAA receptors mediating MCP-1 release. Furthermore, the TLR2 and TLR4 are receptors for dysfunctional HDL. These results give a further inside in SAA as uremic toxin involved in uremia-related pro-inflammatory response in the vascular wall.

Symmetric dimethylarginine is a stronger predictor of mortality risk than asymmetric dimethylarginine among older people with kidney disease

BACKGROUND

Circulating asymmetric dimethylarginine and symmetric dimethylarginine are increased in patients with kidney disease. Symmetric dimethylarginine is considered a good marker of glomerular filtration rate, while asymmetric dimethylarginine is a marker of cardiovascular risk. However, a link between symmetric dimethylarginine and all-cause mortality has been reported. In the present study, we evaluated both dimethylarginines as risk and glomerular filtration rate markers in a cohort of elderly white individuals, both with and without chronic kidney disease.

METHODS

Glomerular filtration rate was measured in 394 individuals aged >74 years using an iohexol clearance method. Plasma asymmetric dimethylarginine, symmetric dimethylarginine and iohexol were measured simultaneously using isotope dilution tandem mass spectrometry.

RESULTS

Plasma asymmetric dimethylarginine concentrations were increased ( P < 0.01) in people with glomerular filtration rate <60 mL/min/1.73 m² compared with those with glomerular filtration rate ≥60 mL/min/1.73 m², but did not differ ( P > 0.05) between those with glomerular filtration rate 30-59 mL/min/1.73 m² and <30 mL/min/1.73 m². Plasma symmetric dimethylarginine increased consistently across declining glomerular filtration rate categories ( P < 0.0001). Glomerular filtration rate had an independent effect on plasma asymmetric dimethylarginine concentration, while glomerular filtration rate, gender, body mass index and haemoglobin had independent effects on plasma symmetric dimethylarginine concentration. Participants were followed up for a median of 33 months. There were 65 deaths. High plasma asymmetric dimethylarginine ( P = 0.0412) and symmetric dimethylarginine ( P < 0.0001) concentrations were independently associated with reduced survival.

CONCLUSIONS

Among elderly white individuals with a range of kidney function, symmetric dimethylarginine was a better marker of glomerular filtration rate and a stronger predictor of outcome than asymmetric dimethylarginine. Future studies should further evaluate the role of symmetric dimethylarginine as a marker of outcome and assess its potential value as a marker of glomerular filtration rate.

Cardiovascular risk in children and adolescents with end stage renal disease

OBJECTIVES

To evaluate cardiovascular involvement in children and adolescents with End Stage Renal Disease (ESRD) and to characterize the main risk factors associated with this outcome.

METHODS

Cross-sectional study of 69 children and adolescents at renal transplantation and 33 healthy individuals matched by age and gender. The study outcomes were left ventricular mass z-score (LVMZ) and carotid artery intima-media thickness (CIMT). The potential risk factors considered were age, gender, CKD etiology, use of oral vitamin D and calcium-based phosphate binders, systolic and diastolic blood pressure, body mass index z-score, time since diagnosis, dialysis duration, serum levels of ionic calcium, phosphorus, parathyroid hormone, fibroblast growth factor (FGF 23), uric acid, homocysteine, cholesterol, triglycerides, C-reactive protein (CRP), vitamin D and hemoglobin.

RESULTS

In the multivariate analysis, the factors associated with LVMZ were dialysis duration, age, systolic blood pressure, serum hemoglobin and HDL cholesterol levels. Regarding CIMT, in the multivariate analysis, systolic blood pressure was the only factor associated with the outcome.

CONCLUSION

Children exhibited important cardiovascular involvement at the time of the renal transplantation. Both of the studied outcomes were independently associated with systolic blood pressure. For this reason, controlling blood pressure seems to be the main therapy to minimize cardiovascular involvement in children with ESRD.

Mechanisms and Modulation of Oxidative/Nitrative Stress in Type 4 Cardio-Renal Syndrome and Renal Sarcopenia

Chronic kidney disease (CKD) is a public health problem and a recognized risk factor for cardiovascular diseases (CVD). CKD could amplify the progression of chronic heart failure leading to the development of type 4 cardio-renal syndrome (T4CRS). The severity and persistence of heart failure are strongly associated with mortality risk in T4CRS. CKD is also a catabolic state leading to renal sarcopenia which is characterized by the loss of skeletal muscle strength and physical function. Renal sarcopenia also promotes the development of CVD and increases the mortality in CKD patients. In turn, heart failure developed in T4CRS could result in chronic muscle hypoperfusion and metabolic disturbances leading to or aggravating the renal sarcopenia. The interplay of multiple factors (e.g., comorbidities, over-activated renin-angiotensin-aldosterone system [RAAS], sympathetic nervous system [SNS], oxidative/nitrative stress, inflammation, etc.) may result in the progression of T4CRS and renal sarcopenia. Among these factors, oxidative/nitrative stress plays a crucial role in the complex pathomechanism and interrelationship between T4CRS and renal sarcopenia. In the heart and skeletal muscle, mitochondria, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, uncoupled nitric oxide synthase (NOS) and xanthine oxidase are major ROS sources producing superoxide anion (O2^·−) and/or hydrogen peroxide (H₂O₂). O2^·− reacts with nitric oxide (NO) forming peroxynitrite (ONOO⁻) which is a highly reactive nitrogen species (RNS). High levels of ROS/RNS cause lipid peroxidation, DNA damage, interacts with both DNA repair enzymes and transcription factors, leads to the oxidation/nitration of key proteins involved in contractility, calcium handling, metabolism, antioxidant defense mechanisms, etc. It also activates the inflammatory response, stress signals inducing cardiac hypertrophy, fibrosis, or cell death via different mechanisms (e.g., apoptosis, necrosis) and dysregulates autophagy. Therefore, the thorough understanding of the mechanisms which lead to perturbations in oxidative/nitrative metabolism and its relationship with pro-inflammatory, hypertrophic, fibrotic, cell death and other pathways would help to develop strategies to counteract systemic and tissue oxidative/nitrative stress in T4CRS and renal sarcopenia. In this review, we also focus on the effects of some well-known and novel pharmaceuticals, nutraceuticals, and physical exercise on cardiac and skeletal muscle oxidative/nitrative stress in T4CRS and renal sarcopenia.