Arterial Stiffness in CKD: A Review

Relationship between carotid-femoral pulse wave velocity and prognosis in maintenance hemodialysis patients

Carotid-femoral pulse wave velocity (Cf-PWV) can well predict the prognosis of the general population. However, whether Cf-PWV can be used as a prognostic indicator in maintenance hemodialysis (MHD) patients remains mysterious. The present study endeavored to explore the prognostic value of Cf-PWV among the MHD population. Patients who received MHD and underwent Cf-PWV examination at the hemodialysis center of Zhejiang Provincial People's Hospital between March 1, 2017 and October 15, 2019 were enrolled. Relevant clinical data were collected from these patients, who were subsequently followed up for a minimum of 1 year. During the follow-up period, the occurrence of all-cause death was recorded as a prognostic indicator. Based on the predetermined inclusion and exclusion criteria 178 patients were included in the final analysis. These patients were categorized into 2 groups based on Cf-PWV values: group 1 (Cf-PWV < 13.8 m/s), and group 2 (Cf-PWV ≥ 13.8 m/s). Thirty-four patients succumbed to their conditions within a median follow-up period of 23.3 months. Kaplan-Meier survival analysis revealed that the median survival time of group 2 was significantly shorter than group 1 (log-rank test, χ2 = 12.413, P < .001). After adjusting for various factors, including age, cardiovascular disease, peripheral arterial diastolic pressure, central arterial diastolic pressure, albumin, blood urea nitrogen, serum creatinine, left ventricular ejection fraction, 25 hydroxyvitamin D3, C-reactive protein and serum phosphorus, it was found that Cf-PWV ≥ 13.8m/s was an independent risk factor for all-cause mortality in MHD patients (relative risk = 3.04, 95% confidence interval [CI] = 1.22-7.57; P = .017). A high level of Cf-PWV (≥13.8 m/s) is an independent risk factor for all-cause death in MHD patients.

Anticoagulation in Chronic Kidney Disease

The nuanced landscape of anticoagulation therapy in patients with chronic kidney disease (CKD) presents a formidable challenge, intricately balancing the dual hazards of hemorrhage and thrombosis. These patients find themselves in a precarious position, teetering on the edge of these risks due to compromised platelet functionality and systemic disturbances within their coagulation frameworks. The management of such patients necessitates a meticulous approach to dosing adjustments and vigilant monitoring to navigate the perilous waters of anticoagulant therapy. This is especially critical considering the altered pharmacokinetics in CKD, where the clearance of drugs is significantly impeded, heightening the risk of accumulation and adverse effects. In the evolving narrative of anticoagulation therapy, the introduction of direct oral anticoagulants (DOACs) has heralded a new era, offering a glimmer of hope for those navigating the complexities of CKD. These agents, with their promise of easier management and a reduced need for monitoring, have begun to reshape the contours of care, particularly for patients not yet on dialysis. However, this is not without its caveats. The application of DOACs in the context of advanced CKD remains a largely uncharted territory, necessitating a cautious exploration to unearth their true potential and limitations. Moreover, the advent of innovative strategies such as left atrial appendage occlusion (LAAO) underscores the dynamic nature of anticoagulation therapy, potentially offering a tailored solution for those at the intersection of CKD and elevated stroke risk. Yet the journey toward integrating such advancements into standard practice is laden with unanswered questions, demanding rigorous investigation to illuminate their efficacy and safety across the spectrum of kidney disease. In summary, the management of anticoagulation in CKD is a delicate dance, requiring a harmonious blend of precision, caution, and innovation. As we venture further into this complex domain, we must build upon our current understanding, embracing both emerging therapies and the need for ongoing research. Only then can we hope to offer our patients a path that navigates the narrow strait between bleeding and clotting, toward safer and more effective care.

Vitamin D therapy in chronic kidney disease: a critical appraisal of clinical trial evidence

In people with chronic kidney disease (CKD), the physiology of vitamin D is altered and leads to abnormalities in bone and mineral metabolism which contribute to CKD mineral and bone disorder (CKD-MBD). Observational studies show an association between vitamin D deficiency and increased risk of mortality, cardiovascular disease and fracture in CKD. Although vitamin D therapy is widely prescribed in people with CKD, clinical trials to date have failed to demonstrate a clear benefit of either nutritional vitamin D supplementation or active vitamin D therapy in improving clinical outcomes in CKD. This review provides an updated critical analysis of recent trial evidence on vitamin D therapy in people with CKD.

Evaluation of vascular aging on measures of cardiac function and mechanical efficiency: insights from in-silico modeling

Introduction

This study evaluated the hypothesis that vascular aging (VA) reduces ventricular contractile function and mechanical efficiency (ME) using the left ventricular pressure-volume (PV) construct.

Methods

A previously published in-silico computational model (CM) was modified to evaluate the hypothesis in two phases. In phase I, the CM included five settings of aortic compliance (CA) from normal to stiff, studied at a heart rate of 80 bpm, and phase II included the normal to stiff CA settings evaluated at 60, 100, and 140 bpm. The PV construct provided steady-state and transient data through a simulated vena caval occlusion (VCO). The steady-state data included left ventricular volumes (EDV and ESV), stroke work (SW), and VCO provided the PV area (PVA) data in addition to the three measures of contractile state (CS): end-systolic pressure-volume relationship (ESPVR), dP/dtmax-EDV and preload recruitable stroke work (PRSW). Finally, ME was calculated with the SW/PVA parameter.

Results

In phase I, EDV and ESV increased, as did SW and PVA. The impact on the CS parameters demonstrated a small decrease in ESPVR, no change in dP/dtmax-EDV, and a large increase in PRSW. ME decreased from 71.5 to 60.8%, respectively. In phase II, at the normal and stiff CA settings, across the heart rates studied, EDV and ESV decreased, ESPVR and dP/dtmax-EDV increased and PRSW decreased. ME decreased from 76.4 to 62.6% at the normal CA and 65.8 to 53.2% at the stiff CA.

Discussion

The CM generated new insights regarding how the VA process impacts the contractile state of the myocardium and ME.

Association of aortic stiffness with abdominal vascular and coronary calcifications in patients with stage 3 and 4 chronic kidney disease

RATIONALE AND OBJECTIVES

Increased central (aortic) arterial stiffness has hemodynamic repercussions that affect the incidence of cardiovascular and renal disease. In chronic kidney disease (CKD) there may be an increase in aortic stiffness secondary to multiple metabolic alterations including calcification of the vascular wall (VC). The objective of this study was to analyze the association of central aortic pressures and aortic stiffness with the presence of VC in abdominal aorta (AAC) and coronary arteries(CAC).

MATERIALS AND METHODS

We included 87 pacientes with CKD stage 3 and 4. Using applanation tonometry, central aortic pressures and aortic stiffness were studied. We investigated the association of aortic pulse wave velocity (Pvc-f) and Pvc-f adjusted for age, blood pressure, sex and heart rate (Pvc-f index) with AAC obtained on lumbar lateral radiography and CAC assessed by multidetector computed tomography. AAC and CAC were scored according to Kauppila and Agatston methods, respecti-vely. For the study of the association between Pvc-f index, Kauppila score, Agatston score, central aortic pressures, clinical parameters and laboratory data, multiple and logistic regression were used. We investigated the diagnosis performance of the Pvc-f index for prediction of VC using receiver-operating characteristic (ROC).

RESULTS

Pvc-f and Pvc-f index were 11.3 ± 2.6 and 10.6 m/s, respectively. The Pvc-f index was higher when CKD coexisted with diabetes mellitus (DM). AAC and CAC were detected in 77% and 87%, respectively. Albuminuria (β = 0.13, p = 0.005) and Kauppila score (β = 0.36, p = 0.001) were independently associated with Pvc-f index. In turn, Pvc-f index (β = 0.39, p = 0.001), DM (β = 0.46, p = 0.01), and smoking (β = 0.53; p = 0.006) were associated with Kauppila score, but only Pvc-f index predicted AAC [OR: 3.33 (95% CI: 1.6-6.9; p = 0.001)]. The Kauppila score was independently associated with the Agatston score (β = 1.53, p = 0.001). The presence of AAC identified patients with CAC with a sensitivity of 73%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 38%. The Vpc-f index predicted the presence of CAC [OR: 3.35 (95% CI: 1.04-10.2, p = 0.04)]. In the ROC curves, using the Vpc-f index, the AUC for AAC and CAC was 0.82 (95%CI: 0.71-0.93, p = 0.001) and 0.81 (95% CI: 0.67-0.96, p = 0.02), respectively.

CONCLUSIONS

When stage 3-4 CKD coexists with DM there is an increase in aortic stiffness determined by the Vpc-f index. In stage 3-4 CKD, AAC and CAC are very prevalent and both often coexist. The Vpc-f index is independently associated with AAC and CAC and may be useful in identifying patients with VC in these territories.

Serum Phenylacetylglutamine among Potential Risk Factors for Arterial Stiffness Measuring by Carotid-Femoral Pulse Wave Velocity in Patients with Kidney Transplantation

Phenylacetylglutamine (PAG), a gut microbiota metabolite, is associated with cardiovascular diseases. Arterial stiffness (AS), which is a marker of aging-associated vascular diseases, is an independent risk factor for cardiovascular morbidity and mortality. This study aimed to assess the correlation between serum PAG levels and AS in kidney transplantation (KT) patients, potentially uncovering new insights into the cardiovascular risks in this population. In this study, 100 KT patients were included. Carotid-femoral pulse wave velocity (cfPWV) was measured, and patients with cfPWV > 10 m/s were categorized as the AS group. Serum PAG levels were assessed using liquid chromatography-tandem mass spectrometry. Thirty KT patients (30.0%) exhibited AS, with higher percentages of diabetes mellitus, older age, and elevated levels of systolic blood pressure, serum fasting glucose, and PAG than the control group. After adjusting for factors significantly associated with AS by multivariate logistic regression analysis, serum PAG, age, fasting glucose levels, and systolic blood pressure were independent factors associated with AS. Furthermore, PAG levels had a negative correlation with the estimated glomerular filtration rate and a positive correlation with cfPWV values. Serum PAG levels are positively associated with cfPWV values and are a biomarker of AS in KT patients.

Exercise for chronic kidney disease: effects on vascular and cardiopulmonary function

Patients with chronic kidney disease (CKD) have an exacerbated prevalence of cardiovascular disease (CVD). Vascular dysfunction, characterized by impaired endothelial function and arterial stiffness, and markedly low cardiorespiratory fitness levels are hallmark manifestations of the disease that contribute to the CVD burden. Despite advancements in blood pressure and lipid lowering pharmacological therapies, CVD remains markedly prevalent across the spectrum of CKD. This highlights a stagnation in effective clinical strategies to improve cardiovascular health and reinforces the critical need for adjuvant lifestyle strategies such as physical activity and exercise training to be incorporated into routine clinical care. This narrative review provides an overview of the known effects of exercise on vascular and cardiopulmonary function across the spectrum of CKD. The physiological mechanisms of vascular dysfunction that serve as exercise-specific therapeutic targets are highlighted and future perspectives are discussed.

Effect of regulated vitamin D increase on vascular markers in patients with chronic kidney disease: A systematic review and meta-analysis of randomized controlled trials

AIM

The effect of increased vitamin D levels on vascular function in patients with chronic kidney disease (CKD) is controversial. This meta-analysis aimed to assess the effect of regulated vitamin D increase on vascular markers in patients with CKD.

DATA SYNTHESIS

We searched PubMed, Web of Science, Embase and ClinicalTrials.gov from database inception up until July 21, 2023. We included randomized controlled trials assessing the effects of using vitamin D and its analogues on vascular function in patients with CKD. Fixed-effects and random-effects model analyses were performed using weighted mean difference effects for each trial by heterogeneity (I2) assessment. Primary outcomes encompassed blood flow-mediated dilation (FMD)、pulse wave velocity (PWV) and augmentation index (AIx).

FINDINGS

From 1964 records we selected 12 trials, 5 (n = 331) on FMD, 8 (n = 626) on PWV and 4 (n = 393) on AIx. Vitamin D and VDRA supplementation failed to significantly improve FMD (WMD 1.68%; 95% CI -0.18 to 3.53; P = 0.08; I2 = 88%)、PWV (WMD -0.41 m/s; 95%CI -0.95 to 0.13; P = 0.14; I2 = 57%)and AIx (WMD -0.53%; 95%CI -1.69 to 0.63; P = 0.37; I2 = 0%). Subgroup analysis revealed that 2 μg paricalcitol significantly improved FMD (WMD 2.09%; 95%CI 1.28 to 2.90; P < 0.00001); I2 = 0%), as did cholecalciferol (WMD 5.49%; 95% CI 4.35 to 6.63; P < 0.00001).

CONCLUSION

Supplementation vitamin D and VDRA are associated with improved vascular function as measured by FMD, but not arterial stiffness as measured by PWV and AIx, tentatively suggesting that regulating the increase of vitamin D could not potentially reduce the incidence of cardiovascular disease.

Association Between Arterial Stiffness and Measures of Autonomic Dysfunction in People With Chronic Kidney Disease

Background

Autonomic nervous system (ANS) dysfunction and vascular stiffness increase cardiovascular risk in people with chronic kidney disease (CKD). Chronic elevations in sympathetic activity can lead to increased arterial stiffness; however, the relationship between these variables is unknown in CKD.

Objective

To explore the association between measures of autonomic function and arterial stiffness in patients with moderate-to-severe CKD.

Methods

This study was a prespecified secondary analysis of a randomized controlled trial. This included the following measures: 24-hour ambulatory blood pressure (BP), carotid-femoral and carotid-radial pulse wave velocity (PWV), and postexercise heart rate recovery (HRR). We used mixed effect linear regression models with Bayesian information criteria (BIC) to assess the contribution of ANS measurements.

Results

Forty-four patients were included in the analysis. Mean carotid-femoral and carotid-radial PWV were 7.12 m/s (95% CI 6.13, 8.12) and 8.51 m/s (7.90, 9.11), respectively. Mean systolic dipping, calculated as percentage change in mean systolic readings from day to night, was 10.0% (95% CI 7.79, 12.18). Systolic dipping was independently associated with carotid-radial PWV, MD -0.09 m/s (95% CI -0.15, -0.02) and had the lowest BIC.

Conclusions

Systolic dipping was associated with carotid-radial PWV in people with moderate-to-severe CKD; however, there was no association with carotid-femoral PWV. Systolic dipping may be a feasible surrogate of ANS function, as the association with carotid-radial PWV was consistent with the minimal clinically important difference (MCID). Future studies are needed to define the relationship between ANS function, arterial stiffness, and CV events over time in people with CKD.

The effect of exercise on vascular health in chronic kidney disease: a systematic review and meta-analysis of randomized controlled trials

Patients with chronic kidney disease (CKD) are at increased risk of cardiovascular disease. This increased risk cannot be fully explained by traditional risk factors such as hypertension. Endothelial dysfunction and arterial stiffness have been suggested as factors that explain some of the increased risk and are independently associated with important cardiovascular outcomes in patients with CKD. Studies in other disease populations have shown the positive effects of exercise on vascular dysfunction. The aim of this review was to determine whether exercise training interventions improve measures of vascular function and morphology in patients across the spectrum of CKD and which exercise training interventions are most efficacious. A systematic search of Medline, Embase, and the Cochrane Central Register identified 25 randomized controlled trials. Only randomized control trials using an exercise intervention with a nonexercising control group and at least one measure of vascular function or morphology were included. Participants were patients with nondialysis CKD or transplant patients or those requiring dialysis therapy. A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A meta-analysis was completed for pulse wave velocity, augmentation index, and measures of endothelium-dependent vasodilation. Data from 25 studies with 872 participants showed that exercise training reduced pulse wave velocity and augmentation index but had no effect on endothelium-dependent vasodilation. Subgroup analyses suggested that exercise interventions of at least moderate intensity were more likely to be effective. Limitations included the absence of observational studies or other interventions aimed at increasing habitual physical activity. Further studies are warranted to investigate which are the most effective exercise interventions.NEW & NOTEWORTHY A thorough systematic review and meta-analysis of the effects of exercise training on measures of vascular function in patients with chronic kidney disease, including arterial stiffness and endothelial function, were conducted. Subgroup analyses investigated how differences in exercise training, according to frequency, intensity, type, and timing, have an impact on the efficacy of the intervention.

Cellular Senescence Contributes to Large Elastic Artery Stiffening and Endothelial Dysfunction With Aging: Amelioration With Senolytic Treatment

BACKGROUND

Here, we assessed the role of cellular senescence and the senescence associated secretory phenotype (SASP) in age-related aortic stiffening and endothelial dysfunction.

METHODS

We studied young (6-8 mo) and old (27-29 mo) p16-3MR mice, which allows for genetic-based clearance of senescent cells with ganciclovir (GCV). We also treated old C57BL/6N mice with the senolytic ABT-263.

RESULTS

In old mice, GCV reduced aortic stiffness assessed by aortic pulse wave velocity (PWV; 477±10 vs. 382±7 cm/s, P<0.05) to young levels (old-GCV vs. young-vehicle, P=0.35); ABT-263 also reduced aortic PWV in old mice (446±9 to 356±11 cm/s, P<0.05). Aortic adventitial collagen was reduced by GCV (P<0.05) and ABT-263 (P=0.12) in old mice. To show an effect of the circulating SASP, we demonstrated that plasma exposure from Old-vehicle p16-3MR mice, but not from Old-GCV mice, induced aortic stiffening assessed ex vivo (elastic modulus; P<0.05). Plasma proteomics implicated glycolysis in circulating SASP-mediated aortic stiffening. In old p16-3MR mice, GCV increased endothelial function assessed via peak carotid artery endothelium-dependent dilation (EDD; Old-GCV, 94±1% vs. Old-vehicle, 84±2%, P<0.05) to young levels (Old-GCV vs. young-vehicle, P=0.98), and EDD was higher in old C57BL/6N mice treated with ABT-263 vs. vehicle (96±1% vs. 82±3%, P<0.05). Improvements in endothelial function were mediated by increased nitric oxide (NO) bioavailability (P<0.05) and reduced oxidative stress (P<0.05). Circulating SASP factors related to NO signaling were associated with greater NO-mediated EDD following senescent cell clearance.

CONCLUSIONS

Cellular senescence and the SASP contribute to vascular aging and senolytics hold promise for improving age-related vascular function.

Vascular ageing: moving from bench towards bedside

Prevention of cardiovascular disease (CVD) remains one of the largest public health challenges of our time. Identifying individuals at increased cardiovascular risk at an asymptomatic, sub-clinical stage is of paramount importance for minimizing disease progression as well as the substantial health and economic burden associated with overt CVD. Vascular ageing (VA) involves the deterioration in vascular structure and function over time and ultimately leads to damage in the heart, brain, kidney, and other organs. Vascular ageing encompasses the cumulative effect of all cardiovascular risk factors on the arterial wall over the life course and thus may help identify those at elevated cardiovascular risk, early in disease development. Although the concept of VA is gaining interest clinically, it is seldom measured in routine clinical practice due to lack of consensus on how to characterize VA as physiological vs. pathological and various practical issues. In this state-of-the-art review and as a network of scientists, clinicians, engineers, and industry partners with expertise in VA, we address six questions related to VA in an attempt to increase knowledge among the broader medical community and move the routine measurement of VA a little closer from bench towards bedside.

Blood pressure and vascular determinants of glomerular filtration rate decline in diabetic kidney disease

Objective

In patients with type 2 diabetes and diabetic kidney disease (DKD), explore the relationship between estimated glomerular filtration rate decline (eGFR-d) and simultaneously assessed vascular risk markers including office, ambulatory or central blood pressure, pulse pressure, carotid-femoral pulse wave velocity (PWV), carotid intima-media thickness (IMT) and renal resistive indexes (RRI).

Research design and methods

At baseline, vascular risk markers were measured in addition to the routine clinical workup. The eGFR-d was based on 2000-2019 creatinine values. Parameters were compared by eGFR-d quartiles. Regression models of eGFR-d and vascular markers were assessed.

Results

In total, 135 patients were included. Mean age was 63.8 ± 10.8y, baseline eGFR 60.2 ± 26.4 ml/min/1.73 m2 and urine albumin-creatinine ratio (ACR) 49 ± 108 mg/mmol. Mean eGFR-d was based on 43 ± 39 creatinine values within a time span of 7.0 ± 1.9y. The average yearly eGFR decline was -1.8 ± 3.0 ml/min/1.73 m2 ranging from -5.8 ± 2.3 in the first quartile to +1.4 ± 1.7 in the fourth quartile. Mean 24 h systolic (SBP) and diastolic (DBP) blood pressure were 126 ± 17 and 74 ± 9 mmHg. Mean PWV was 11.8 ± 2.8 m/s, RRI 0.76 ± 0.07 and IMT 0.77 ± 0.21 mm. SBP and pulse pressure correlated with eGFR-d but not DBP. 24 h SBP stood out as a stronger predictor of eGFR-d than office or central SBP. PWV and RRI correlated with eGFR decline in univariate, but not multivariate regression models including 24 SBP and ACR.

Conclusions

In this study, eGFR decline was highly variable in patients with type 2 diabetes and DKD. Twenty-four hour SBP provided an added value to the routine measurement of ACR in predicting eGFR decline, whereas PWV and RRI did not.

Triiodothyronine and Protein Malnutrition Could Influence Pulse Wave Velocity in Pre-Dialysis Chronic Kidney Disease Patients

Cardiovascular diseases (CVD) are the first cause of chronic kidney disease (CKD) mortality. For personalized improved medicine, detecting correctable markers of CVD can be considered a priority. The aim of this study was the evaluation of the impact of nutritional, hormonal and inflammatory markers on brachial-ankle Pulse Wave Velocity (PWV) in pre-dialysis CKD patients. A cross-sectional observational study was conducted on 68 pre-dialysis CKD patients (median age of 69 years, 41.2% with diabetes mellitus, 52.9% male). Laboratory data were collected, including levels of prolactin, triiodothyronine, TGF α, IL-6, and IL-1β. The high values of brachial-ankle PWV were associated with reduced muscle mass (p = 0.001, r = -0.44), low levels of total cholesterol (p = 0.04, r = -0.26), triglycerides (p = 0.03, r = -0.31), triiodothyronine (p = 0.04, r = -0.24), and prolactin (p = 0.02, r = -0.27). High PWV was associated with advanced age (p < 0.001, r = 0.19). In the multivariate analysis, reduced muscle mass (p = 0.018), low levels of triiodothyronine (p = 0.002), and triglycerides (p = 0.049) were significant predictors of PWV, but age (p < 0.001) remained an important factor. In conclusion, reduced triiodothyronine together with markers of malnutrition and age were associated with PWV in pre-dialysis CKD patients.

The impact of anticoagulation therapy on kidney function in patients with atrial fibrillation and chronic kidney disease

INTRODUCTION

Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related. These diseases share common risk factors and are associated with increased risk of thromboembolic events. Choosing the appropriate oral anticoagulant therapy (OAC) in patients with AF and CKD is challenging. Deterioration of renal function is common in patients with AF treated with OACs, although not all OACs affect the kidneys equally.

AREAS COVERED

In this review, we aim to summarize the current knowledge of the prevention of thromboembolic events in patients with AF and CKD, focusing on the impact of specific OAC agents on renal function.

EXPERT OPINION

Consideration of OAC use is mandatory in patients with AF and CKD who are at increased risk of stroke or systemic embolism. Available evidence suggests that the use of non-vitamin K antagonist oral anticoagulants (NOACs) is associated with slower deterioration of renal function in comparison to Vitamin K antagonists (VKAs). Hence, a NOAC should be used in preference to VKAs in all NOAC-eligible patients with AF and CKD. Regarding patients with end-stage renal dysfunction and those on dialysis or renal replacement therapy, the use of NOAC should be considered in line with locally relevant formal recommendations.

The Role of Two Heart Biomarkers in IgA Nephropathy

Cardiovascular mortality is a leading cause of death in chronic kidney disease (CKD), as is IgA nephropathy (IgAN). The purpose of this study is to find different biomarkers to estimate the outcome of the disease, which is significantly influenced by the changes in vessels (characterized by arterial stiffness) and the heart. In our cross-sectional study, 90 patients with IgAN were examined. The N-terminal prohormone of brain natriuretic peptide (NT-proBNP) was measured as a heart failure biomarker by an automated immonoassay method, while the carboxy-terminal telopeptide of collagen type I (CITP) as a fibrosis marker was determined using ELISA kits. Arterial stiffness was determined by measuring carotid-femoral pulse wave velocity (cfPWV). Renal function and routine echocardiography examinations were performed as well. Based on eGFR, patients were separated into two categories, CKD 1-2 and CKD 3-5. There were significantly higher NT-proBNP (p = 0.035), cfPWV (p = 0.004), and central aortic systolic pressure (p = 0.037), but not CITP, in the CKD 3-5 group. Both biomarker positivities were significantly higher in the CKD 3-5 group (p = 0.035) compared to the CKD 1-2 group. The central aortic systolic pressure was significantly higher in the diastolic dysfunction group (p = 0.034), while the systolic blood pressure was not. eGFR and hemoglobin levels showed a strong negative correlation, while left ventricular mass index (LVMI), aortic pulse pressure, central aortic systolic pressure, and cfPWV showed a positive correlation with NT-proBNP. cfPWV, aortic pulse pressure, and LVMI showed a strong positive correlation with CITP. Only eGFR was an independent predictor of NT-proBNP by linear regression analysis. NT-proBNP and CITP biomarkers may help to identify IgAN patients at high risk for subclinical heart failure and further atherosclerotic disease.

Blood Pressure Variability and the Progression of Chronic Kidney Disease: a Systematic Review and Meta-Analysis

BACKGROUND

Blood pressure variability (BPV) is a risk factor for poor prognosis including cardiovascular events, chronic kidney disease, and mortality, independent of elevated BP.

METHODS

We searched PubMed/Medline, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to November 23, 2022. Cohort studies reporting the association between BPV and chronic kidney disease (CKD) progression were selected. Hazard ratios were pooled using a random-effects model. Meta-regression, subgroup analyses, and sensitivity analyses were conducted.

RESULTS

A total of 23 studies were included in this systematic review and meta-analysis. Increased BPV was associated with progression of CKD (HR: 1.21, 95% CI: 1.09-1.33) and incidence of ESRD (HR: 1.08, 95% CI: 1.08-1.30). Among the different BPV metrics, high variation independent of mean (VIM), coefficient of variation (CV), standard deviation (SD), and average real variability (ARV) were indicated as predictors of CKD progression.

DISCUSSION

Increased BPV was associated with CKD progression.

A comparative study of the effects of chronic kidney disease on sonographic arterial stiffness parameters in geriatric and normal population

Aim: Due to its growing incidence rate worldwide, chronic kidney disease is a crucial public health problem which is strongly associated with cardiovascular disease. Cardiovascular disease in chronic kidney disease patients is characterized by arteriosclerosis and increased arterial stiffness, and is the leading cause of morbidity and mortality. A correlation was reported between an increased arterial stiffness and cardiovascular disease in high risk groups such as chronic kidney disease or hypertension as well as general undiagnosed population. Our aim was to show the changes in arterial stiffness parameters in patients with chronic kidney disease in the geriatric population. Material and Method: 44 chronic kidney disease patients and 44 control group cases of the same age were included in the study. There were 20 female and 24 male cases in each group. Systolic and diastolic diameter were measured for all cases. Intima-media thickness was measured in carotid and femoral arteries. Arterial stiffness parameters were calculated using formulas. Systolic and diastolic arterial blood pressure and body mass index were measured. Their urea and creatinine values were recorded. Results: There were no differences between two groups in terms of age and sex (p=0.069). Body mass index in the patient group was significantly lower compared to the control group (p=0.025). Systolic arterial blood pressure was higher in the patient group (p

Accelerated AGEing: The Impact of Advanced Glycation End Products on the Prognosis of Chronic Kidney Disease

Advanced glycation end products (AGEs) are aging products. In chronic kidney disease (CKD), AGEs accumulate due to the increased production, reduced excretion, and the imbalance between oxidant/antioxidant capacities. CKD is therefore a model of aging. The aim of this review is to summarize the present knowledge of AGEs in CKD onset and progression, also focusing on CKD-related disorders (cardiovascular diseases, sarcopenia, and nutritional imbalance) and CKD mortality. The role of AGEs as etiopathogenetic molecules, as well as potential markers of disease progression and/or therapeutic targets, will be discussed.

Effect of the administration of different forms of vitamin D on central blood pressure and aortic stiffness, and its implication in the reduction of albuminuria in chronic kidney disease

BACKGROUND AND OBJECTIVES

Vitamin D(vitD) participates in phospho-calcium metabolism and exerts multiple pleiotropic effects. There is tissue 1-α (OH)ase that converts 25-OH cholecalciferol (25 (OH) D) in calcitriol that exerts autocrine and paracrine effects. 25 (OH)D deficiency could limit these tissue effects of vitD. The administration of nutritional vitD and the activator of the vitD receptor, paricalcitol, may promote beneficial effects on vascular and renal function. The objective of this work was to study in subjects with chronic kidney disease (CKD) the effect that the administration of different forms of vitD has on arterial function and albuminuria, and the possible relationship between the modifications of these variables.

PATIENTS AND METHODS

We studied in 97 patients with CKD stages 3-4 the effect of the administration of cholecalciferol (group 2; n: 35) and paricalcitol (n: 31; group 3) on parameters derived from brachial blood pressure, aortic blood pressure and on aortic stiffness studied using carotid-femoral pulse velocity (Vp_c-f), and on albuminuria. A group of patients with stages 3-4 CKD who did not receive vitD therapy served as a control group (n: 31; group 1). All parameters were studied at baseline and after the follow-up period which was 7 ± 2 months.

RESULTS

In the baseline phase, no differences were observed between the groups in brachial systolic blood pressure (bSBP), central systolic blood pressure (SBP), brachial pulse pressure (bPP), and central pulse pressure (pCP) or in aortic stiffness that was increased in all groups with a baseline Vp_c-f value of 10.5 (9.2-12.1) m/sec. The baseline albuminuria value in the grouped patients was 229 (43-876) mg / g (median (interquartile range)), with no differences between the groups. Serum calcium and phosphorus increased significantly in those treated with cholecal-ciferol (native vitD) and paricalcitol (active vitD). Parathormone (PTH) values decreased in those treated with paricalcitol.bPP and cPP decreased in all groups treated with native and active vitD. No significant changes in bPP and cPP were observed in the control group. Vp_c-f did not change significantly in any of the groups, although the variation was quantitatively greater in group 3 (11.2±2 vs. 10.7±1.6 (P=.06)). No differences were observed in the changes in Vp_c-f between the groups when adjusted to the baseline values of estimated glomerular filtration rate (eGFR), albuminuria, PTH, vitD, brachial and central blood pressure parameters, and their changes with treatment.Those who received treatment with native and active vitD presented a significant decrease in albuminuria of 17% (group 2) and 21% (group 3) compared to a 16% increase in the untreated group (group 1) (P=.01). A decrease in albuminuria ≥30% was observed more frequently in the groups treated with some form of vitD (group 2: 23%; group 3: 45%) than in the control group (13%) (P=.03). The decrease in albuminuria observed in the groups treated with any of the forms of vitD did not vary when the baseline values of the biochemical parameters of phosphorus-calcium metabolism, those of arterial function (PPb, PPc, Vp_c-f) or its modifications were introduced as covariates. There was no significant correlation between changes in Vp_c-f and albuminuria. In logistic regression, changes in arterial function parameters were also not explanatory for the ≥30% decrease in albuminuria.

CONCLUSIONS

In patients with CKD stages 3-4, treated with RAS blockers and with residual albuminuria, the administration of or paricalcitol reduces brachial and aortic pulse pressures, and albuminuria. The decrease in albuminuria does not seem to be mediated, at least not decisively, by changes in central hemodynamics or aortic stiffness.

Promoting healthy cardiovascular aging: emerging topics

The development of age-related cardiovascular (CV) dysfunction increases the risk of CV disease as well as other chronic age-associated disorders, including chronic kidney disease, and Alzheimer's disease and related dementias. Major manifestations of age-associated CV dysfunction that increase disease risk are vascular dysfunction, primarily vascular endothelial dysfunction and arterial stiffening, and elevated systolic blood pressure. Declines in nitric oxide bioavailability secondary to increased oxidative stress and inflammation are established mechanisms of CV dysfunction with aging. Moreover, fundamental mechanisms of aging, termed the "hallmarks of aging" extend to the CV system and, as such, may be considered "hallmarks of CV aging". These mechanisms represent viable therapeutic targets for treating CV dysfunction with aging. Healthy lifestyle behaviors, such as regular aerobic exercise and certain dietary patterns, are considered "first-line" strategies to prevent and/or treat age-associated CV dysfunction. Despite the well-established benefits of these strategies, many older adults do not meet the recommended guidelines for exercise or consume a healthy diet. Therefore, it is important to establish alternative and/or complementary evidence-based approaches to prevent or reverse age-related CV dysfunction. Targeting fundamental mechanisms of CV aging with interventions such as time-efficient exercise training, food-derived molecules, termed nutraceuticals, or select synthetic pharmacological agents represents a promising approach. In the present review, we will highlight emerging topics in the field of healthy CV aging with a specific focus on how exercise, nutrition/dietary patterns, nutraceuticals and select synthetic pharmacological compounds may promote healthy CV aging, in part, by targeting the hallmarks of CV aging.

Atorvastatin can delay arterial stiffness progression in hemodialysis patients

Purpose

Arterial stiffness is one of the vascular pathologies in hemodialysis (HD) patients with increased cardiovascular mortality and morbidity. Few approaches have been tested to reduce arterial stiffness in patients with chronic kidney disease (CKD). We aimed to assess effects of atorvastatin on arterial stiffness in hemodialysis patients.

Methods

This research is a double-blinded, placebo-controlled, randomized clinical trial which included 50 patients maintained on regular HD. Patients were allocated to receive 10 mg atorvastatin or placebo for 24 weeks. Aortic pulse wave velocity (PWV) as an index of large artery stiffness and augmentation index (AIx) as an index of wave reflections were assessed at baseline and after 6 months in both groups.

Results

In atorvastatin group at study end, there was no significant difference from baseline findings in aortic PWV (7.86 ± 2.5 vs 7.88 ± 2.6 m/sec; p = 0.136), AIx (26.04 ± 8.5 vs 26.0 ± 8.6%; p = 0.714) and central pulse pressure (PP) (p = 1.0). On the other hand, in placebo group after 24 weeks, aortic PWV (7.80 ± 2.16 vs 7.63 ± 2.1 m/sec; p < 0.001), AIx (25.88 ± 9.4 vs 25.04 ± 9.4%; p < 0.001) increased significantly from baseline measurements but central pulse pressure (PP) (p = 0.870) did not. Also, the change (Δ) in aortic PWV and AIx was significantly higher than the change in the atorvastatin group with p value of < 0.001 and < 0.001, respectively.

Conclusions

Arterial stiffness parameters remained stable in atorvastatin group but increased significantly in placebo-treated patients suggesting a potential role for atorvastatin to delay arterial stiffness progression in HD patients. Larger randomized clinical trials are needed to confirm these findings.

Clinical Trials registration

ClinicalTrials.gov NCT04472637.

Aortic stiffness and aortic-brachial stiffness mismatch as markers of renal dysfunction in hypertension

PURPOSE

The dismal combination of hypertension and chronic kidney disease potentiates both cardiovascular disease and loss of renal function. Research points to the importance of arterial and left ventricular stiffening in this process but few studies have compared aspects of central and peripheral hemodynamics in relation to renal function in hypertension.

MATERIALS AND METHODS

We investigated 107 hypertensive individuals with renal function ranging from normal to severe dysfunction with pulse wave analysis to obtain central blood pressures (BP), augmentation index, carotid-femoral and carotid-radial pulse wave velocity (cfPWV, crPWV), aortic-to-brachial stiffness mismatch (cfPWV/crPWV), endothelial function by forearm flow-mediated vasodilation and myocardial microvascular function by subendocardial viability ratio, and indices of left ventricular structure (left ventricular mass index and relative wall thickness, RWT) and diastolic function (left atrial volume index, E/A, and E/é).

RESULTS

Mean age was 58 years, BP 149/87 mm Hg, 9% had cardiovascular disease, and 31% were on antihypertensive treatment. Mean estimated glomerular filtration rate (eGFR) was 74 (range 130-21) ml/min × 1.73 m². Whereas cfPWV and cfPWV/crPWV were independently related to eGFR (r = -0.20, p = 0.002, r = -0.16, p = 0.01), central diastolic BP (r = 0.21, p = 0.04), RWT (r = -0.34, p = 0.001), E/é (r = -0.39, p < 0.001) and E/A (r = 0.27, p = 0.01) were related to eGFR in bivariate correlations, but these findings were not retained in multivariate analyses. Remaining markers of hypertensive heart disease and measures of microvascular function were not related to eGFR.

CONCLUSION

Increased aortic stiffness and aortic-to-brachial stiffness mismatch are independently related to reduced eGFR in hypertensive patients, suggesting an important role for aortic stiffness in the evolution of hypertension-mediated renal dysfunction. Aortic stiffness and aortic-brachial stiffness mismatch may be useful early markers to find hypertensive patients at risk for decline in renal function.

Arterial Stiffness and Adult Onset Vasculitis: A Systematic Review

Chronic inflammation represents the cornerstone of the raised cardiovascular (CV) risk in patients with inflammatory rheumatic diseases (IRD), including vasculitis. Standardized mortality ratios in these patients are higher as compared to the general population, and the excess of premature mortality is due to early atherosclerotic events. Thus, IRD patients need appropriate CV risk assessment and management according to this CV disease (CVD) burden. Adequate control of CV risk is still lacking in usual care, but early diagnosis of silent and subclinical CVD is crucial to improve the long-term prognosis of these patients. Increased arterial stiffness may provide a pathophysiological link between inflammation and increased cardiovascular risk. Several noninvasive methods are now available to estimate artery stiffness in the clinical setting, including pulse wave velocity assessment. The independent predictive value of arterial stiffness for cardiovascular events has been demonstrated in general as well as in selected populations, and reference values adjusted for age and blood pressure have been suggested. Thus, arterial stiffness is an interesting biomarker for cardiovascular risk stratification. This systematic review summarizes the additional value that PWV measurement can provide in the setting of vasculitis, with a focus in the different clinical stages and CV risk prevention. This systematic review is registered with registration number: Prospero CRD42021259603.

Kidney disease parameters, metabolic goal achievement, and arterial stiffness risk in Chinese adult people with type 2 diabetes

BACKGROUND

To investigate the arterial stiffness (AS) risk within urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) categories and the joint effect between kidney disease parameters and metabolic goal achievement on AS risk in adult people with type 2 diabetes (T2D).

METHODS

A total of 27 439 Chinese participants with T2D from 10 National Metabolic Management Centers (MMC) were categorized into four albuminuria/decreased eGFR groups. The criteria for decreased eGFR and AS were eGFR <90 ml/min/1.73 m² and brachial-ankle pulse wave velocity value >the 75th percentile (1770.0 cm/s). Three metabolic goals were defined as glycated hemoglobin <7%, BP <130/80 mmHg, andlow-density lipoprotein cholesterol <2.6 mmol/L.

RESULTS

After full adjustment, odds ratios (ORs) for AS were highest for albuminuria and decreased eGFR (2.23 [1.98-2.52]) and were higher for albuminuria and normal eGFR (1.52 [1.39-1.67]) than for those with nonalbuminuria and decreased eGFR (1.17 [1.04-1.32]). Both UACR and eGFR in the subgroup or overall population independently correlated with AS risk. The achievement of ≥2 metabolic goals counteracted the association between albuminuria and AS risk (OR: 0.93; 95% CI: 0.80-1.07; p = .311). When the metabolic goals added up to ≥2 for patients with decreased eGFR, they showed significantly lower AS risk (OR: 0.65; 95% CI: 0.56-0.74; p < .001).

CONCLUSIONS

Both higher UACR and lower eGFR are determinants of AS risk, with UACR more strongly related to AS than eGFR in adults with T2D. The correlation between albuminuria/decreased eGFR and AS was modified by the achievement of multiple metabolic elements.

Metabolomics of Arterial Stiffness

Arterial stiffness (AS) is one of the earliest detectable signs of structural and functional alterations of the vessel wall and an independent predictor of cardiovascular events and death. The emerging field of metabolomics can be utilized to detect a wide spectrum of intermediates and products of metabolism in body fluids that can be involved in the pathogenesis of AS. Research over the past decade has reinforced this idea by linking AS to circulating acylcarnitines, glycerophospholipids, sphingolipids, and amino acids, among other metabolite species. Some of these metabolites influence AS through traditional cardiovascular risk factors (e.g., high blood pressure, high blood cholesterol, diabetes, smoking), while others seem to act independently through both known and unknown pathophysiological mechanisms. We propose the term 'arteriometabolomics' to indicate the research that applies metabolomics methods to study AS. The 'arteriometabolomics' approach has the potential to allow more personalized cardiovascular risk stratification, disease monitoring, and treatment selection. One of its major goals is to uncover the causal metabolic pathways of AS. Such pathways could represent valuable treatment targets in vascular ageing.

Investigation of the Relationship between Cardiovascular Biomarkers and Brachial-Ankle Pulse Wave Velocity in Hemodialysis Patients

Brachial−ankle pulse wave velocity (baPWV) and cardiovascular (CV) biomarkers are correlated with clinical cardiovascular diseases (CVDs) in patients with kidney disease. However, limited studies evaluated the relationship between baPWV and CV biomarkers in hemodialysis patients. This study investigated the relationship between circulating CV biomarkers and baPWV in patients on hemodialysis. Hemodialysis patients were enrolled between August 2016 and January 2017 for the measurement of baPWV, traditional CV biomarkers, including high-sensitivity troponin-T (hsTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), and novel CV biomarkers, including Galectin-3, Cathepsin D, placental growth factor, Endocan-1, and Fetuin-A. The independent association was assessed by multivariate-adjusted linear regression analysis to control for potential confounders. The final analysis included 176 patients (95 men and 81 women) with a mean age of 60 ± 11 y old. After adjusting for age and sex, hsTnT (p < 0.01), NT-proBNP (p = 0.01), Galectin-3 (p = 0.03), and Cathepsin D (p < 0.01) were significantly directly correlated with baPWV. The direct correlation with baPWV existed in multivariable linear regression models with a β of 0.1 for hsTnT and 0.1 for Cathepsin D. The direct relationship between baPWV and CV biomarkers, particularly with hsTnT and Cathepsin D, may be helpful for risk stratification of hemodialysis patients.

Aortic Stiffness and Pulsatile Pressures as Potential Mediators of Chronic Kidney Disease Induced Impaired Diastolic Function

Purpose

We assessed whether aortic stiffness and pulsatile pressures can mediate chronic kidney disease (CKD)-associated impaired diastolic function.

Participants and Methods

In 276 black Africans including 46 CKD (19 non-dialysis; 27 dialysis) and 230 control subjects, pulse wave velocity (PWV) estimated aortic stiffness and pulsatile pressures (forward and backward wave pressure, central systolic blood pressure (CSBP) and pulse pressure (CPP)) were determined by applanation tonometry; e’ as an index of left ventricular active relaxation and E/e’ as a measure of left ventricular filling pressure or passive relaxation were evaluated by echocardiography.

Results

In age, sex, traditional cardiovascular risk factor and mean arterial pressure (MAP) adjusted regression models, CKD was inversely associated with e’ (p = 0.03) and directly with E/e’ (p < 0.01). The CKD-e’ relationship was attenuated and no longer significant (p = 0.31) upon additional adjustment for aortic PWV but not pulsatile pressures (p = 0.03–0.05). In product of coefficient mediation analysis, PWV accounted for 47.6% of the CKD-e’ association. CSBP (22.9%) and CPP (18.6%) but not PWV (11.3%) accounted for a significant and relevant proportion of the CKD-E/e’ relationship. However, CKD remained strongly associated with E/e’ independent of aortic function measures (p < 0.01). Treatable covariates that were or tended to be consistently associated with diastolic function included MAP (p < 0.01) and diabetes (p = 0.02–0.07) for the CKD-e’ and CKD-E/e’ relations, respectively.

Conclusion

Aortic stiffness rather than pulsatile pressures mediates CKD-related impaired left ventricular active relaxation. By contrast, aortic pulsatile pressures (and not stiffness) contribute to CKD-related left ventricular filling pressures but do not fully account for the respective association.

The central arterial stiffness parameters in decompensated versus compensated states of heart failure: a paired comparative cohort study

Background

Arterial stiffness is strongly linked to the pathogenesis of heart failure and the development of acute decompensation in patients with stable chronic heart failure. This study aimed to compare arterial stiffness indices in patients with heart failure with reduced ejection fraction (HFrEF) during the acute decompensated state, and three months later after hospital discharge during the compensated state.

Results

One hundred patients with acute decompensated HFrEF (NYHA class III and IV) and left ventricular ejection fraction ≤ 35% were included in the study. During the initial and follow-up visits, all patients underwent full medical history taking, clinical examination, transthoracic echocardiography, and non-invasive pulse wave analysis by the Mobil-O-Graph 24-h device for measurement of arterial stiffness. The mean age was 51.6 ± 6.1 years and 80% of the participants were males. There was a significant reduction of the central arterial stiffness indices in patients with HFrEF during the compensated state compared to the decompensated state. During the decompensated state, patients presented with NYHA FC IV (n = 64) showed higher AI (24.5 ± 10.0 vs. 16.8 ± 8.6, p < 0.001) and pulse wave velocity (9.2 ± 1.3 vs. 8.5 ± 1.2, p = 0.021) than patients with NYHA FC III, and despite the relatively smaller number of females, they showed higher stiffness indices than males.

Conclusions

Central arterial stiffness indices in patients with HFrEF were significantly lower in the compensated state than in the decompensated state. Patients with NYHA FC IV and female patients showed higher stiffness indices in their decompensated state of heart failure.

Interactions Between Kidney Function and Cerebrovascular Disease: Vessel Pathology That Fires Together Wires Together

The kidney and the brain, as high-flow end organs relying on autoregulatory mechanisms, have unique anatomic and physiological hemodynamic properties. Similarly, the two organs share a common pattern of microvascular dysfunction as a result of aging and exposure to vascular risk factors (e.g., hypertension, diabetes and smoking) and therefore progress in parallel into a systemic condition known as small vessel disease (SVD). Many epidemiological studies have shown that even mild renal dysfunction is robustly associated with acute and chronic forms of cerebrovascular disease. Beyond ischemic SVD, kidney impairment increases the risk of acute cerebrovascular events related to different underlying pathologies, notably large artery stroke and intracerebral hemorrhage. Other chronic cerebral manifestations of SVD are variably associated with kidney disease. Observational data have suggested the hypothesis that kidney function influences cerebrovascular disease independently and adjunctively to the effect of known vascular risk factors, which affect both renal and cerebral microvasculature. In addition to confirming this independent association, recent large-scale human genetic studies have contributed to disentangling potentially causal associations from shared genetic predisposition and resolving the uncertainty around the direction of causality between kidney and cerebrovascular disease. Accelerated atherosclerosis, impaired cerebral autoregulation, remodeling of the cerebral vasculature, chronic inflammation and endothelial dysfunction can be proposed to explain the additive mechanisms through which renal dysfunction leads to cerebral SVD and other cerebrovascular events. Genetic epidemiology also can help identify new pathological pathways which wire kidney dysfunction and cerebral vascular pathology together. The need for identifying additional pathological mechanisms underlying kidney and cerebrovascular disease is attested to by the limited effect of current therapeutic options in preventing cerebrovascular disease in patients with kidney impairment.

Chronic Kidney Disease and Arterial Stiffness: A Two-Way Path

The kidney-heart relationship has raised interest for the medical population since its vast and complex interaction significantly impacts health. Chronic kidney disease (CKD) generates vascular structure and function changes, with significant hemodynamic effects. The early arterial stiffening in CKD patients is a consequence of the interaction between oxidative stress and chronic vascular inflammation, leading to an accelerated deterioration of left ventricular function and alteration in tissue perfusion. CKD amplifies the inflammatory cascade's activation and is responsible for altering the endothelium function, increasing the vascular tone, wall thickening, and favors calcium deposits in the arterial wall. Simultaneously, the autonomic imbalance, and alteration in other hormonal systems, also favor the overactivation of inflammatory and fibrotic mediators. Thus, hormonal disarrangement also contributes to structural and functional lesions throughout the arterial wall. On the other hand, a rise in arterial stiffening and volume overload generates high left ventricular afterload. It increases the left ventricular burden with consequent myocardial remodeling, development of left ventricular hypertrophy and, in turn, heart failure. It is noteworthy that reduction in glomerular mass of renal diseases generates a compensatory glomerular filtration overdriven associated with large-arteries stiffness and high cardiovascular events. Furthermore, we consider that the consequent alterations of the arterial system's mechanical properties are crucial for altering tissue perfusion, mainly in low resistance. Thus, increasing the knowledge of these processes may help the reader to integrate them from a pathophysiological perspective, providing a comprehensive idea of this two-way path between arterial stiffness and renal dysfunction and their impact at the cardiovascular level.

Accuracy of Ankle-Brachial Index, Toe-Brachial Index, and Risk Classification Score in Discriminating Peripheral Artery Disease in Patients With Chronic Kidney Disease

The accuracy of ankle-brachial index (ABI) and toe-brachial index (TBI) in discriminating lower extremity peripheral artery disease (PAD) has not been evaluated in patients with chronic kidney disease (CKD). We measured ABI, TBI, and Doppler ultrasound in 100 predialysis patients with CKD without revascularization or amputation. Leg-specific ABI was calculated using higher systolic blood pressure (SBP) in posterior tibial or dorsalis pedis artery divided by higher brachial SBP; alternative ABI was calculated using lower SBP in posterior tibial or dorsalis pedis artery. PAD was defined as ≥50% stenosis detected by Doppler ultrasound. PAD risk classification score was calculated using cardiovascular disease risk factors. The area under the curve (AUC, 95% confidence interval [CI]) for discriminating ultrasound-diagnosed PAD was 0.78 (0.69 to 0.87) by ABI, 0.80 (0.71 to 0.89) by alternative ABI, and 0.74 (0.63 to 0.86) by TBI. Sensitivity and specificity were 25% and 97% for ABI ≤0.9, 41% and 95% for alternative ABI ≤0.9, and 45% and 93% for TBI ≤0.7, respectively. AUC (95% CI) of PAD risk classification score was 0.86 (0.78 to 0.94) with sensitivity and specificity of 95% and 60% for risk score ≥0.10, 76% and 76% for risk score ≥0.25, and 43% and 95% for risk score ≥0.55. Combining risk score with ABI, alternative ABI, and TBI increased AUC (95% CI) to 0.89 (0.82 to 0.96), 0.89 (0.80 to 0.98), and 0.87 (0.78 to 0.96), respectively. In conclusion, current ABI and TBI diagnostic criteria have high specificity but low sensitivity for classifying PAD in patients with CKD. PAD classification risk score based on cardiovascular disease risk factors improves the accuracy of PAD classification.

Glomerular Hyperfiltration Interacts With Abnormal Metabolism to Enhance Arterial Stiffness in Middle-Aged and Elderly People

Introduction: Glomerular hyperfiltration (GHF) is an early kidney injury. We investigated whether GHF is associated with arterial stiffness expressed by increase of brachial-ankle pulse wave velocity (baPWV) and pulse pressure (PP), and whether the coexistence of GHF and abnormal metabolism increases the risk of arterial stiffness. Methods: In this prospective cohort study, 2,133 non-chronic kidney disease (CKD) participants aged ≥40 years were followed for a mean period of 3.3 years. The extent of arterial stiffness was expressed by measures of baPWV and PP. GHF was defined as eGFR exceeding the age- and sex-specific 90th percentile. Multivariate logistic regression models were used to assess the association between GHF/abnormal metabolism and increased baPWV/PP. The interaction indexes of GHF and abnormal metabolism on arterial stiffness were calculated based on the OR in a multivariate logistic regression model. Results: GHF alone was not associated with increased baPWV or PP in all participants in this study. However, when GHF coexisted with abnormal metabolism, the risk of increased PP increased 3.23-fold [OR = 3.23(1.47-7.13)] compared with participants with normal filtration and normal metabolism, in which the interaction accounted for 55.1% of the total effect and 79.8% of the effect from GHF and abnormal metabolism. After subtracting the independent effects of GHF and abnormal metabolism, their combined effect still resulted in a 1.78-fold increase in PP. Conclusion: GHF could interact with abnormal metabolism to significantly enhance arterial stiffness. Since abnormal metabolism commonly exists in the general population, even slight changes in renal function should be distinguished to prevent arterial stiffness risk.

Kidney Function and Aortic Stiffness, Pulsatility, and Endothelial Function in African Americans: The Jackson Heart Study

Rationale & Objective

The relation of vascular stiffness, endothelial function, and kidney function is incompletely elucidated in African Americans. Our hypothesis was that increased vascular stiffness and endothelial dysfunction are associated with low estimated glomerular filtration rate (eGFR) and albuminuria in African Americans.

Study Design

Cross-sectional cohort analysis of data from the Jackson Heart Study.

Settings & Patients

2,244 Jackson Heart Study participants (2012-2017 after Exam 3) who had undergone noninvasive hemodynamic assessment using arterial tonometry.

Predictors

Baseline carotid-femoral pulse wave velocity, pulsatile hemodynamics forward wave amplitude, and hyperemic brachial artery flow were measured. Reduced eGFR was defined as eGFR between 15 and 60 mL/min/1.73 m².

Outcomes

Prevalent albuminuria, urinary albumin-creatinine ratio.

Analytical Approach

2-sample t test for continuous variables and χ² test for categorical variables in addition to logistic and linear regression models to assess the risk for chronic kidney disease with each proposed hemodynamic variable.

Results

Among 2,244 participants, mean age was 66 ± 11 years and 64% were women. Reduced eGFR was present in 233 (10.4%), and elevated urinary albumin-creatinine ratio, in 232 (10.4%). In multivariable-adjusted analyses, higher carotid-femoral pulse wave velocity was associated with the presence of reduced eGFR (OR, 1.37 [95% CI, 1.08-1.75] per SD; P = 0.01) and with prevalent albuminuria (OR, 1.66 [95% CI, 1.32-2.11]; P < 0.001). Higher forward wave amplitude was significantly associated with prevalent albuminuria (OR, 1.37 [95% CI, 1.14-1.65]; P = 0.001).

Limitations

Cross-sectional analyses cannot inform causality.

Conclusions

Higher arterial stiffness and pulsatility are associated with higher odds of reduced eGFR in African Americans. Future studies should focus on whether improving arterial stiffness contributes to kidney protection in African Americans.

Non-valvular Atrial Fibrillation in CKD: Role of Vitamin K Antagonists and Direct Oral Anticoagulants. A Narrative Review

Atrial fibrillation (AF) is the most common arrhythmia in chronic kidney disease (CKD), with a close bidirectional relationship between the two entities. The presence of CKD in AF increases the risk of thromboembolic events, mortality and bleeding. Vitamin K antagonists (VKA) have been the mainstay of treatment for the prevention of thromboembolic events in AF until recently, with confirmed benefits in AF patients with stage 3 CKD. However, the risk-benefit profile of VKA in patients with AF and stages 4-5 CKD is controversial due to the lack of evidence from randomized controlled trials. Treatment with VKA in CKD patients has been associated with conditions such as poorer anticoagulation quality, increased risk of bleeding, faster progression of vascular/valvular calcification and higher risk of calciphylaxis. Direct oral anticoagulants (DOACs) have shown equal or greater efficacy in stroke/systemic embolism prevention, and a better safety profile than VKA in post-hoc analysis of the pivotal randomized controlled trials in patients with non-valvular AF and stage 3 CKD, yet evidence of its risk-benefit profile in more advanced stages of CKD is scarce. Observational studies associate DOACs with a good safety/effectiveness profile compared to VKA in non-dialysis CKD patients. Further, DOACs have been associated with a lower risk of acute kidney injury and CKD development/progression than VKA. This narrative review summarizes the evidence of the efficacy and safety of warfarin and DOACs in patients with AF at different CKD stages, as well as their effects on renal function, vascular/valvular calcification and bone health.

Association of Arterial Stiffness With Chronic Kidney Disease Progression and Mortality

Chronic kidney disease (CKD) is a major public health concern. Despite many potentially life-threatening conditions that can accompany kidney disease, cardiovascular disease (CVD) remains the leading cause of death in these patients. Adjusted-for-age mortality from CVD in patients with end-stage renal disease is 10-30 times higher than in the general population. A decrease in renal function accelerates the development of cardiac pathology. Simultaneous exposure of CVD and CKD plays an important role in the relationship between arterial stiffness (AS) and estimated glomerular filtration rate. But there is a controversy as to whether the AS causes deterioration in kidney function, if renal dysfunction leads to AS, or the relationship is reciprocal. Hence, several studies that recruited high-risk populations reached a conclusion that comorbidities might lead to both AS and decline in kidney function over time. A number of studies have shown that several markers of AS, such as pulse pressure, central and peripheral pressure are associated with the development of CKD. This review takes into account the theoretical background, current status, and future potential of the techniques that measure AS within context of CKD assessment and management.

Advances in vascular anatomy and pathophysiology using high resolution and multiparametric sonography

B-mode and Color Doppler are the first-line imaging modalities in cardiovascular diseases. However, conventional ultrasound (US) provides a lower spatial and temporal resolution (70-100 frames per second) compared to ultrafast technology which acquires several thousand frames per second. Consequently, the multiparametric ultrafast platforms manage new imaging algorithms as high-frequency ultrasound, contrast-enhanced ultrasound, shear wave elastography, vector flow, and local pulse wave imaging. These advances allow better ultrasound performances, more detailed blood flow visualization and vessel walls' characterization, and many future applications for vascular viscoelastic properties evaluation.In this paper, we provide an overview of each new technique's principles and concepts and the real or potential applications of these modalities on the study of the artery and venous anatomy and pathophysiology of the upper limb before and after creating a native or prosthetic arterio-venous fistula. In particular, we focus on high-frequency ultrasound that could predict cannulation readiness and its potential role in the venous valvular status evaluation before vascular access creation; on contrast-enhanced ultrasound that could improve the peri-operative imaging evaluation during US-guided angioplasty; on shear wave elastography and local pulse wave imaging that could evaluate preoperative vessels stiffness and their potential predictive role in vascular access failure; on vector flow imaging that could better characterize the different components of the vascular access complex flow.

Chronic Kidney Disease-Induced Arterial Media Calcification in Rats Prevented by Tissue Non-Specific Alkaline Phosphatase Substrate Supplementation Rather Than Inhibition of the Enzyme

Patients with chronic kidney disease (CKD) suffer from arterial media calcification and a disturbed bone metabolism. Tissue-nonspecific alkaline phosphatase (TNAP) hydrolyzes the calcification inhibitor pyrophosphate (PPi) into inorganic phosphate (Pi) and thereby stimulates arterial media calcification as well as physiological bone mineralization. This study investigates whether the TNAP inhibitor SBI-425, PPi or the combination of both inhibit arterial media calcification in an 0.75% adenine rat model of CKD. Treatments started with the induction of CKD, including (i) rats with normal renal function (control diet) treated with vehicle and CKD rats treated with either (ii) vehicle, (iii) 10 mg/kg/day SBI-425, (iv) 120 µmol/kg/day PPi and (v) 120 µmol/kg/day PPi and 10 mg/kg/day SBI-425. All CKD groups developed a stable chronic renal failure reflected by hyperphosphatemia, hypocalcemia and high serum creatinine levels. CKD induced arterial media calcification and bone metabolic defects. All treatments, except for SBI-425 alone, blocked CKD-related arterial media calcification. More important, SBI-425 alone and in combination with PPi increased osteoid area pointing to a less efficient bone mineralization. Clearly, potential side effects on bone mineralization will need to be assessed in any clinical trial aimed at modifying the Pi/PPi ratio in CKD patients who already suffer from a compromised bone status.

The Relationship between Advanced Oxidation Protein Products, Vascular Calcifications and Arterial Stiffness in Predialysis Chronic Kidney Disease Patients

Background and Objectives: Cardiovascular morbidity and mortality are increased in patients with chronic kidney disease (CKD). It is likely that the accumulation of uremic toxins resulting in increased oxidative stress (OS) is a major contributing factor, but no clear link has been identified. The purpose of this research is to establish if advanced oxidation protein product (AOPP) levels in the serum of predialysis patients are a contributing factor to vascular calcification and increased arterial stiffness. Materials and Methods: After obtaining the informed consent, 46 predialysis patients (CKD stages G3-G5) were included in the study. In order to identify vascular calcifications, hand and pelvic radiographs were performed. Valvular calcifications were identified using cardiac ultrasound. AOPP were measured using a commercially available ELISA kit. The relationships between serum AOPP values and biochemical parameters relevant in the evaluation of CKD patients were analyzed. In addition to identifying the differences in AOPP levels between patients with/without vascular or valvular calcifications, the research focused on describing the relationship between OS and arterial stiffness assessed by oscillometric pulse-wave velocity (PWV) measurement. Results: No significant relationship between serum AOPP and vascular or valvular calcifications was highlighted, but significant correlations of AOPP with C-reactive protein (p = 0.025), HDL-cholesterol levels (p = 0.04), HbA1c (p = 0.05) and PWV values (p = 0.02) were identified. Conclusions: The usefulness of (OS) measurement in clinical practice remains debatable; however, the relationship between AOPP and arterial stiffness could be valuable in improving cardiovascular risk assessment of patients with CKD.

Oral anticoagulation in chronic kidney disease with atrial fibrillation

Chronic kidney disease (CKD) and atrial fibrillation (AF) frequently coexist, amplifying the risk of cardiovascular events and mortality. In patients with CKD stage 3 and non-valvular AF, direct oral anticoagulants (DOACs) have shown, compared to vitamin K antagonists (VKA), equal or greater efficacy in the prevention of stroke and systemic embolism, and greater safety. There are no randomizedtrials of the efficacy and safety of DOACs and VKA in advanced CKD. On the other hand, observational studies suggest that DOACs, compared to warfarin, are associated with a lower risk of acute kidney damage and generation/progression of CKD. This paper reviews the epidemiological and pathophysiological aspects of the CKD and AF association, the evidence of the efficacy and safety of warfarin and ACODs in various stages of CKD with AF as well as the comparison between warfarin and ACODs in efficacy and anticoagulant safety, and in its renal effects.

Sedentary Behavior and Change in Kidney Function: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

BACKGROUND

There is accumulating evidence linking prolonged sedentary time to adverse health outcomes. The effect of sedentary behavior on kidney function has not been evaluated in US Hispanics/Latinos, a population disproportionately affected by CKD.

METHODS

We evaluated the association between accelerometer-measured (1 week) sedentary time at baseline and kidney function among 7134 adults without CKD at entry in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), who completed a baseline visit with accelerometry (2008-2011) and a follow-up visit (2014-2017). Outcomes included: (1) change in kidney function (eGFR and urine albumin-to-creatinine ratio, ACR), (2) incident low eGFR (eGFR <60 ml/min per 1.73 m2 and eGFR decline ≥1 ml/min per year), and (3) incident albuminuria (ACR ≥17 mg/g in men or ≥25 mg/g in women). Linear regression using survey procedures was used to evaluate change in kidney function (eGFR and ACR), and Poisson regression with robust variance was used to evaluate incident low eGFR and albuminuria.

RESULTS

The median sedentary time was 12 hours/d. Over a median follow-up of 6.1 years, the mean relative change in eGFR was -0.50% per year, and there were 167 incident low eGFR events. On multivariable analysis, each 1 hour increase in sedentary time was associated with a longitudinal decline in eGFR (-0.06% per year, 95% CI, -0.10 to -0.02). There was a significant interaction with sex, and on stratified analyses, higher sedentary time was associated with eGFR decline in women but not men. There was no association between sedentary time and the other outcomes.

CONCLUSIONS

Sedentary time was associated with a small longitudinal decline in eGFR, which could have important implications in a population that experiences a disproportionate burden of CKD but further investigation is needed.

[Cardiovascular disorders in autosomal dominant polycystic kidney disease]

Autosomal dominant polycystic kidney disease is the most frequent genetic kidney disease. Cardiovascular disorders associated with autosomal dominant polycystic kidney disease are multiple and may occur early in life. In autosomal dominant polycystic kidney disease cardiovascular morbidity and mortality are related both to the nonspecific consequences of chronic kidney disease and to the particular phenotype of autosomal dominant polycystic kidney disease. Compared to the general population, patients with autosomal dominant polycystic kidney disease present an increased prevalence of hypertension, left ventricular hypertrophy, atrial fibrillation, valvular diseases, aneurisms and arterial dissections. This review article provides an update on cardiovascular disorders associated with autosomal dominant polycystic kidney disease and recent pathophysiological developments.

Carotid-Femoral Pulse Wave Velocity as a Risk Marker for Development of Complications in Type 1 Diabetes Mellitus

Background

The value of carotid‐femoral pulse wave velocity (cfPWV) as risk factor for development of complications in type 1 diabetes mellitus remains to be determined. We investigated associations between cfPWV and renal outcomes, cardiovascular events, and all‐cause mortality in people with type 1 diabetes mellitus.

Methods and Results

cfPWV was measured with SphygmoCor in 633 people with type 1 diabetes mellitus. Median (interquartile range) follow‐up was 6.2 (5.8−6.7) years. End points included progression in albuminuria group, decline in estimated glomerular filtration rate (eGFR) ≥30%, end‐stage kidney disease, cardiovascular event, mortality, and a composite renal end point. Hazard ratios (HRs) were calculated per 1‐SD increase in cfPWV. Adjustments included age, sex, hemoglobin A1c, mean arterial pressure, body mass index, low‐density lipoprotein cholesterol, smoking, urine albumin excretion rate, and eGFR. The cohort included 45% women, mean (SD) age was 54 (13) years, mean (SD) eGFR was 83.2 (27.9) mL/min per 1.73 m², and mean (SD) cfPWV was 10.4 (3.3) m/s. Median (interquartile range) albumin excretion rate was 17 (17‐63) mg/24 h. After adjustment, higher cfPWV was associated with increased hazard of progression in albuminuria (HR, 1.59; 95% CI, 1.10−2.32); decline in eGFR ≥30% (HR, 1.38; 95% CI, 1.06−1.79); cardiovascular event (HR, 1.31; 95% CI, 1.01−1.70); mortality (HR, 1.36; 95% CI, 1.00−1.85); and the composite renal end point (HR, 1.30; 95% CI, 1.04−1.63), but not with end‐stage kidney disease (HR, 1.18; 95% CI, 0.62−2.26). Higher cfPWV was associated with steeper yearly increase in albumin excretion and steeper yearly decline in eGFR after adjustment (P=0.002 and P=0.01, respectively).

Conclusions

cfPWV was associated with increased hazard of renal outcomes, cardiovascular event, and mortality. cfPWV may be suited for risk stratification in type 1 diabetes mellitus.

Aortic pulse wave velocity, central pulse pressure, augmentation index and chronic kidney disease progression in individuals with type 2 diabetes: a 3- year prospective study

BACKGROUND

Pulse wave velocity (PWV), central pulse pressure and augmentation index are arterial stiffness- related hemodynamic parameters but their associations with renal outcome are still controversial. We hereby aim to study, 1) which hemodynamic parameter is independently associated with progressive chronic kidney disease (CKD), 2) the association of 3-year change in PWV with CKD progression and, 3) the additive predictive value of PWV for progressive CKD.

METHODS

Carotid- femoral PWV, central pulse pressure and augmentation index were measured in 1444 participants with type 2 diabetes at baseline and 3 years apart. Progressive CKD was defined as confirmed eGFR decline 40% or greater.

RESULTS

In the follow-up, 102 participants experienced progressive CKD. All 3 hemodynamic parameters were significantly associated with progressive CKD In univariable analysis. However, only PWV remained statistically significant after adjustment for known clinical risk factors and the other 2 hemodynamic parameters (OR 1.14 [95% CI 1.01-1.29] per m/s increment). One m/s regression (decrement) in PWV in the 3-year follow-up was associated with 26% lower adjusted- risk of progressive CKD (OR 0.74, 95% CI 0.56-0.97). Adding PWV onto traditional risk factor- based model significantly improved classification (net reclassification improvement 0.25, 95% CI 0.05-0.45, P = 0.01) and positive prediction rate (24.5 to 32.3%).

CONCLUSIONS

Of 3 arterial stiffness- related hemodynamic parameters, only PWV is independently associated with progressive CKD. PWV may be a potential intervention target to mitigate risk of CKD progression and also a biomarker to improve risk-stratification of adverse renal outcome in individuals with type 2 diabetes.

A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of an Omega-3 Fatty Acid Supplement in Patients With Predialysis Chronic Kidney Disease

OBJECTIVE

Omega-3 fatty acids may reduce albuminuria and cardiovascular risk factors in patients with chronic kidney disease (CKD). We aimed to assess the effects of omega-3 fatty acid supplementation on albuminuria, blood pressure, pulse wave velocity, and inflammatory markers in patients with CKD.

METHODS

Patients with CKD and a urine albumin excretion of at least 30 mg/g creatinine were supplemented for 3 months with 3,666 mg/day of docosahexaenoic and eicosapentaenoic acids or a corn oil supplement. The study was double blind. At baseline, 6 weeks, and 12 weeks, fasting blood and morning spot urine samples were obtained. Blood pressure, carotid intima media thickness, and pulse wave velocity were measured. The main outcome measure was a reduction of ≥20% in urine albumin.

RESULTS

One hundred patients were randomized (50 received omega-3 fatty acids and 50 received corn oil). Four patients who received omega-3 fatty acids and 5 who received vegetable oil were lost to follow-up. In patients receiving omega-3 fatty acids, the omega-3 index increased from 3.08 (2.32-3.81) to 5.48 (3.045-7.04) percent. A 20% reduction in urine albumin excretion was observed in 13 participants of the control group and 19 participants of omega-3 group (Fisher's exact P = .274). However, the supplement had a significant and positive effect on pulse wave velocity and triglyceride level.

CONCLUSION

An omega-3 fatty acid supplement of 3,666 mg/day did not modify urine albumin excretion in patients with CKD but did improve pulse wave velocity and serum triglyceride levels.

Predictive value of cardio-ankle vascular index for the risk of end-stage renal disease

Background

Arterial stiffness is associated with increased cardiovascular morbidity and mortality. However, the predictive value of the cardio-ankle vascular index (CAVI), one of the indicators for arterial stiffness, for the risk of end-stage renal disease (ESRD) remains unknown.

Methods

A total of 8701 patients with documented CAVI measurements by pulse wave velocity (PWV) were included in the study. Patients were divided according to the quartiles of CAVI. The hazard ratio (HR) of ESRD was calculated using the Cox model, after adjustment for multiple variables or death.

Results

During the median follow-up period of 7 years (maximum 12 years), ESRD and mortality occurred in 203 and 1071 patients, respectively. The median value of CAVI was 8.5 (interquartile range 7.7–9.3). The risk of ESRD was higher in the fourth-quartile group than the first-quartile group [adjusted HR 2.46 (IQR 1.62–3.71), P < 0.001]. When a death-adjusted risk analysis was performed, the fourth quartile of CAVI had a higher risk of ESRD than the first quartile [adjusted HR 2.35 (IQR 1.58–3.49), P < 0.001].

Conclusions

The measurement of CAVI by PWV may be needed to predict the risk of ESRD.

State of the Art Review: Brachial-Ankle PWV

The brachial-ankle pulse wave velocity (brachial-ankle PWV), which is measured simply by wrapping pressure cuffs around the four extremities, is a simple marker to assess the stiffness of the medium- to large- sized arteries. The accuracy and reproducibility of its measurement have been confirmed to be acceptable. Risk factors for cardiovascular disease, especially advanced age and high blood pressure, are reported to be associated with an increase of the arterial stiffness. Furthermore, arterial stiffness might be involved in a vicious cycle with the development/progression of hypertension, diabetes mellitus and chronic kidney disease. Increase in the arterial stiffness is thought to contribute to the development of cardiovascular disease via pathophysiological abnormalities induced in the heart, brain, kidney, and also the arteries themselves. A recent independent participant data meta-analysis conducted in Japan demonstrated that the brachial-ankle PWV is a useful marker to predict future cardiovascular events in Japanese subjects without a previous history of cardiovascular disease, independent of the conventional model for the risk assessment. The cutoff point may be 16.0 m/s in individuals with a low risk of cardiovascular disease (CVD), and 18.0 m/s in individuals with a high risk of CVD and subjects with hypertension. In addition, the method of measurement of the brachial-ankle PWV can also be used to calculate the inter-arm systolic blood pressure difference and ankle-brachial pressure index, which are also useful markers for cardiovascular risk assessment.

Targeting Vascular Calcification in Chronic Kidney Disease

Cardiovascular (CV) disease remains an important cause of morbidity and mortality for patients with chronic kidney disease (CKD). Although clustering of traditional risk factors with CKD is well recognized, kidney-specific mechanisms are believed to drive the disproportionate burden of CV disease. One perturbation that is frequently observed at high rates in patients with CKD is vascular calcification, which may be a central mediator for an array of CV sequelae. This review summarizes the pathophysiological bases of intimal and medial vascular calcification in CKD, current strategies for diagnosis and management, and posits vascular calcification as a risk marker and therapeutic target.