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

Effects of Sacubitril/Valsartan Across the Spectrum of Renal Impairment in Patients With Heart Failure

BACKGROUND

The Kidney Disease Improving Global Outcomes (KDIGO) classification integrates both estimated glomerular filtration rate and urine-albumin-creatinine ratio to stratify risk more comprehensively in patients with chronic kidney disease. There are limited data assessing whether this classification system is associated with prognosis and treatment response in heart failure populations.

OBJECTIVES

The aim of this study was to evaluate the relative treatment effects of sacubitril/valsartan across the KDIGO risk categories in patients with HFrEF.

METHODS

PARADIGM-HF (Prospective Comparison of ARNI with ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) was a global randomized controlled trial evaluating sacubitril/valsartan vs enalapril in patients with heart failure with reduced ejection fraction (HFrEF). Patients were classified according to low, moderate, and high/very high KDIGO risk. Treatment responses were assessed according to baseline KDIGO risk. The primary outcome was a composite of cardiovascular (CV) death or heart failure hospitalization. A renal composite outcome was defined as sustained decline in estimated glomerular filtration rate by ≥40% or end-stage kidney disease.

RESULTS

Among 1,910 (23% of total) participants with available data, 42%, 32%, and 26% were classified as low, moderate, and high/very high KDIGO risk, respectively. Patients in the highest KDIGO risk categories experienced the highest rates of the primary composite outcome (7.6 per 100 person-years [95% CI: 6.5-9.0 per 100 person-years], 9.4 per 100 person-years [95% CI: 7.9-11.2 per 100 person-years], and 14.9 per 100 person-years [95% CI: 12.7-17.6 per 100 person-years]; P < 0.001). Sacubitril/valsartan had a similar safety profile and demonstrated consistent effects on the risk of both the primary outcome (PInteraction = 0.31) and the renal composite outcome (PInteraction = 0.50) across the spectrum of KDIGO risk.

CONCLUSIONS

One in 4 patients with HFrEF were classified as at least high KDIGO kidney risk; these individuals faced concordantly the highest risks of CV events. Sacubitril/valsartan exhibited consistent CV and kidney protective benefits as well as safety across the spectrum of baseline kidney risk. These data further support initiation of sacubitril/valsartan in HFrEF across a broad range of kidney risk. (This Study Will Evaluate the Efficacy and Safety of LCZ696 Compared to Enalapril on Morbidity and Mortality of Patients With Chronic Heart Failure [PARADIGM-HF]; NCT01035255).

The relationship between low levels of albuminuria and mortality among adults without major cardiovascular risk factors

AIMS

The determine if elevated levels of albuminuria within the low range (urinary albumin-to-creatinine ratio, UACR <30 mg/g) are linked to cardiovascular death in adults lacking major cardiovascular risk factors.

METHODS

The association between UACR and cardiovascular mortality was investigated among 12,835 participants in the 1999-2014 National Health and Nutrition Examination Survey using Cox proportional hazard models and confounder-adjusted survival curves. We excluded participants with baseline cardiovascular disease, hypertension, diabetes, pre-diabetes, estimated glomerular filtration rate (eGFR) <60ml/min/1.73m2, currently pregnant, and those who had received dialysis in the last year.

RESULTS

Over a median follow-up of 12.3 years, 110 and 621 participants experienced cardiovascular and all-cause mortality. In multivariable-adjusted models, each doubling of UACR was associated with a 36% higher risk of cardiovascular death [HR 1.36 (95% confidence interval (CI) 1.02-1.82)] and a 24% higher risk of all-cause mortality [HR 1.24 (95% CI 1.10-1.39)]. The 15-year adjusted cumulative incidences of cardiovascular mortality were 0.91%, 0.99%, and 2.1% for UACR levels of <4.18 mg/g, 4.18 to <6.91 mg/g, and ≥6.91 mg/g, respectively. The 15-year adjusted cumulative incidences of all-cause mortality were 5.1%, 6.1%, and 7.4% for UACR levels of <4.18 mg/g, 4.18 to <6.91 mg/g, and ≥6.91 mg/g, respectively.

CONCLUSIONS

Adults with elevated levels of albuminuria within the low range (UACR <30 mg/g) and no major cardiovascular risk factors had elevated risks of cardiovascular and all-cause mortality. The risks increased linearly with higher albuminuria levels. This emphasizes a risk gradient across all albuminuria levels, even within the supposedly normal range, adding to the existing evidence.

Associations of serum 25-hydroxyvitamin D and vitamin D receptor polymorphisms with risks of cardiovascular disease and mortality among patients with chronic kidney disease: a prospective study

BACKGROUND

Evidence regarding the relationships of serum 25-hydroxyvitamin D [25(OH)D] with cardiovascular diseases (CVD) and mortality among patients with chronic kidney disease (CKD) is limited and inconsistent.

OBJECTIVES

This study aimed to investigate the associations between serum 25(OH)D and CVD incidence and mortality among patients with CKD.

METHODS

This prospective study included 21,507 participants with CKD and free of CVD in the UK Biobank. Incidences of total and subtypes of CVD and mortality were ascertained via electronic health records. Cox proportional hazard regression models were used to estimate the hazard ratios (HRs) and 95% confidential intervals (CIs) for CVD incidence and mortality.

RESULTS

The median serum 25(OH)D concentration was 44.0 nmol/L (interquartile range: 30.1, 60.6 nmol/L). After multivariable adjustment, compared with CKD patients with serum 25(OH)D concentrations of <25 nmol/L, those with serum 25(OH)D ≥75 nmol/L had HRs (95% CIs) of 0.80 (0.71, 0.90) for total CVD incidence, 0.82 (0.69, 0.97) for ischemic heart disease, 0.56 (0.41, 0.77) for stroke, 0.64 (0.46, 0.88) for myocardial infarction, 0.62 (0.49, 0.80) for heart failure, 0.60 (0.43, 0.85) for CVD mortality, and 0.62 (0.52, 0.74) for all-cause mortality. In addition, these associations were not modified by vitamin D receptor polymorphisms, with no significant interaction detected.

CONCLUSIONS

Higher serum 25(OH)D concentrations were significantly associated with lower risks of total and subtypes of CVD incidence and mortality among individuals with CKD. These findings highlight the importance of maintaining adequate vitamin D status in the prevention of CVD and mortality in patients with CKD.

A Klotho-Based Machine Learning Model for Prediction of both Kidney and Cardiovascular Outcomes in Chronic Kidney Disease

Introduction

This study aimed to develop and validate machine learning (ML) models based on serum Klotho for predicting end-stage kidney disease (ESKD) and cardiovascular disease (CVD) in patients with chronic kidney disease (CKD).

Methods

Five different ML models were trained to predict the risk of ESKD and CVD at three different time points (3, 5, and 8 years) using a cohort of 400 non-dialysis CKD patients. The dataset was divided into a training set (70%) and an internal validation set (30%). These models were informed by data comprising 47 clinical features, including serum Klotho. The best-performing model was selected and used to identify risk factors for each outcome. Model performance was assessed using various metrics.

Results

The findings showed that the least absolute shrinkage and selection operator regression model had the highest accuracy (C-index = 0.71) in predicting ESKD. The features mainly included in this model were estimated glomerular filtration rate, 24-h urinary microalbumin, serum albumin, phosphate, parathyroid hormone, and serum Klotho, which achieved the highest area under the curve (AUC) of 0.930 (95% CI: 0.897-0.962). In addition, for the CVD risk prediction, the random survival forest model with the highest accuracy (C-index = 0.66) was selected and achieved the highest AUC of 0.782 (95% CI: 0.633-0.930). The features mainly included in this model were age, history of primary hypertension, calcium, tumor necrosis factor-alpha, and serum Klotho.

Conclusion

We successfully developed and validated Klotho-based ML risk prediction models for CVD and ESKD in CKD patients with good performance, indicating their high clinical utility.

Complete versus culprit-only percutaneous coronary intervention in elderly patients with acute coronary syndrome and multivessel coronary artery disease: A systematic review and meta-analysis

BACKGROUND

Culprit-only percutaneous coronary intervention (PCI) is commonly performed for acute coronary syndrome (ACS) with multivessel coronary artery disease (MVD) in the elderly. Complete revascularization has been shown to benefit the general population, yet its safety and efficacy in older patients are uncertain.

METHODS

Following PRISMA guidelines, we systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing complete versus culprit-only PCI in patients ≥65 years old with ACS and MVD. The primary outcome was major adverse cardiovascular events (MACE). Secondary outcomes included myocardial infarction (MI), ischemia-driven revascularization (IDR), all-cause mortality, and cardiovascular mortality. Data were pooled using a random effects model with a restricted maximum likelihood estimator to generate risk ratios (RRs).

RESULTS

Five RCTs with 4105 patients aged ≥65 years were included. Compared with culprit-only PCI, complete revascularization reduced MI (RR 0.65; 95 % CI 0.49-0.85; p < 0.01). MACE (RR 0.75; 95 % CI 0.54-1.05; p = 0.09) and IDR (RR 0.41; 95 % CI 0.16-1.04; p = 0.06) were not significantly different between both strategies among those aged ≥65. However, there was a significant reduction in MI (RR 0.69; 95 % CI 0.49-0.96; p-value = 0.03), MACE (RR 0.78; 95 % CI 0.65-0.94; p < 0.01), and IDR (RR 0.60; 95 % CI 0.41-0.89; p < 0.01) in those aged ≥75.

CONCLUSIONS

In elderly patients aged ≥65 years with ACS and MVD, a strategy of complete revascularization by PCI reduces MI compared to culprit-only PCI with no significant difference in MACE and IDR. However, complete revascularization reduced MI, MACE, and IDR in those aged ≥75 years suggesting a possible benefit in this age group.

Angiotensin receptor blocker-neprilysin inhibitor for heart failure with reduced ejection fraction

Heart failure with reduced ejection fraction (HFrEF) is a clinical syndrome characterized by volume overload, impaired exercise capacity, and recurrent hospital admissions. A major contributor to the pathophysiology and clinical presentation of heart failure is the activation of the renin-angiotensin-aldosterone system (RAAS). Normally, RAAS is responsible for the homeostatic regulation of blood pressure, extracellular fluid volume, and serum sodium concentration. In HFrEF, RAAS gets chronically activated in response to decreased cardiac output, further aggravating the congestion and cardiotoxic effects. Hence, inhibition of RAAS is a major approach in the pharmacologic treatment of those patients. The most recently introduced RAAS antagonizing medication class is angiotensin receptor blocker/ neprilysin inhibitor (ARNI). In this paper, we discuss ARNIs' superiority over traditional RAAS antagonizing agents in reducing heart failure hospitalization and mortality. We also tease out the evidence that shows ARNIs' renoprotective functions in heart failure patients including those with chronic or end stage kidney disease. We also discuss the evidence showing the added benefit resulting from combining ARNIs with a sodium-glucose cotransporter-2 (SGLT-2) inhibitor. Moreover, how ARNIs decrease the risk of arrhythmias and reverse cardiac remodeling, ultimately lowering the risk of cardiovascular death, is also discussed. We then present the positive outcome of ARNIs' use in patients with diabetes mellitus and those recovering from acute decompensated heart failure. ARNIs' side effects are also appreciated and discussed. Taken together, the provided insight and critical appraisal of the evidence justifies and supports the implementation of ARNIs in the guidelines for the treatment of HFrEF.

Coronary angiography in patients with kidney dysfunction and myocardial injury: A retrospective cohort study on management of myocardial injury in hospitalized patients with kidney disease

BACKGROUND

Although kidney insufficiency has been shown to be associated with increased risk of myocardial injury, benefit of coronary angiography (CAG) and revascularization remains uncertain, with implications on management strategies and outcomes. We aimed to compare rates of CAG and revascularization and subsequent risk of cardiovascular and kidney outcomes in hospitalized patients with myocardial injury and kidney dysfunction.

METHODS

Retrospective cohort study encompassing hospitalized patients with myocardial injury i.e. elevated troponin I or T and an eGFR ≤60 ml/min/1.73 m2 identified between 2011 and 2021 in Danish national registers. 30-day odds for CAG were computed across granular eGFR-categories based on multiple logistic regression. Standardized one-year risks of cardiovascular and kidney outcomes including mortality were determined based on hazards obtained in multiple Cox regression.

RESULTS

A total of 52,798 patients with myocardial injury were identified. CAG was performed in 14.3 % (n = 7549). 30-day odds ratios for CAG were 0.64 [0.60-0.68], 0.38 [0.34-0.42], 0.18 [0.14-0.22], and 0.35 [0.30-0.40] in patients with eGFR 31-45 ml/min/1.73 m2, eGFR 15-30 ml/min/1.73 m2 for eGFR<15 ml/min/1.73 m2 and chronic dialysis, respectively (eGFR 46-60 ml/min/1.73 m2 as reference). Median follow-up was 4.1 years. One-year mortality risk differences associated with CAG and revascularization (no CAG as reference) were -7.8 [-7.0; -8.7] and -9.1 [-8.4; -9.9] for eGFR 46-60 ml/min/1.73 m2; -7.0 [-5.7;-8-3] and -8.0 [-6.6; -9.5] for eGFR 31-45 ml/min/1.73 m2; -5.4 [-3.0; -7.2] and -5.2 [-2.2; -8.3] for eGFR 15-30 ml/min/1.73 m2; -8.8 [-3.1; -13.7] and -5.4 [3.1; -13.4] for eGFR<15 ml/min/1.73 m2; and -4.9 [-0.1; -9.7] and -4.2 [1.5; -9.2] for chronic dialysis, respectively.

CONCLUSION

Probability of CAG following myocardial injury declined with progressive kidney dysfunction. Overall, CAG was associated with lower mortality irrespective of kidney function and subsequent revascularization.

Targeting Pharmacotherapies for Inflammatory and Cardiorenal Endpoints in Kidney Disease

ABSTRACT

Inflammation is an important contributor to excess cardiovascular risk and progressive renal injury in people with chronic kidney disease (CKD). Dysregulation of the innate and adaptive immune system is accelerated by CKD and results in increased systemic inflammation, a heightened local vascular inflammatory response leading to accelerated atherosclerosis, and dysfunction of the cardiac and renal endothelium and microcirculation. Understanding and addressing the dysregulated immune system is a promising approach to modifying cardiorenal outcomes in people with CKD. However, targeted pharmacotherapies adopted from trials of non-CKD and cardiorheumatology populations are only beginning to be developed and tested in human clinical trials. Pharmacotherapies that inhibit the activation of the NOD-like receptor protein 3 inflammasome and the downstream cytokines interleukin-1 and interleukin-6 are the most well-studied. However, most of the available evidence for efficacy is from small clinical trials with inflammatory and cardiorenal biomarker endpoints, rather than cardiovascular event endpoints, or from small CKD subgroups in larger clinical trials. Other pharmacotherapies that have proven beneficial for cardiorenal endpoints in people with CKD have been found to have pleiotropic anti-inflammatory benefits including statins, mineralocorticoid receptor antagonists, sodium-glucose cotransporter 2 inhibitors, and glucagon-like peptide-1 agonists. Finally, emerging therapies in CKD such as interleukin-6 inhibition, small-interfering RNA against lipoproteins, aryl hydrocarbon receptor inhibitors, and therapies adopted from the renal transplant population including mammalian target of rapamycin inhibitors and T regulatory cell promoters may have benefits for cardiorenal and inflammatory endpoints but require further investigation in clinical trials.

Kidney dysfunction predicts 90 days mortality after stroke thrombectomy independent of cardiovascular risk factors and chronic kidney disease

INTRODUCTION

Kidney dysfunction (KD) is a risk factor for cerebrovascular events and has been shown to have a detrimental effect on outcome after stroke. We evaluated the influence of KD at admission and pre-existing diagnosis of chronic kidney disease (CKD) before thrombectomy for anterior circulation stroke on functional independence and mortality 90 days after stroke in this cross-sectional study.

PATIENTS AND METHODS

We included patients with acute ischemic stroke in the anterior circulation treated with thrombectomy at our hospital between June 2015 and May 2022. We analyzed clinical characteristics, laboratory values and pre-existing diagnosis of CKD. KD at admission was defined as glomerular filtration rate (GFR) <60 ml/min/1.73 m2. Outcomes were defined as a modified Rankin Scale Score of 0-2 for functional independence and mortality at 90 days. We fitted multivariate regression analysis to examine the influence of pre-treatment KD and pre-diagnosed CKD on outcome.

RESULTS

Nine hundred fifty-three patients were included in this analysis (mean age 73.8 years, 54.2% female). KD was present in 31.8%, and patients with KD were older and more often female, presented more often with comorbidities such as arterial hypertension, diabetes, and atrial fibrillation, and were less often independent before the index stroke. In multivariate analysis adjusted for age, independence before the index stroke, diabetes, hypertension, atrial fibrillation, initial NIHSS, thrombolysis treatment, and recanalization outcome, KD on admission had no significant influence on functional independence 90 days after stroke, but predicted mortality with an odds ratio of 1.80 (95% CI 1.23-2.63, p = 0.003). This influence also persisted when controlling for pre-diagnosed CKD (OR 1.60, 95% CI 1.05-2.43, p = 0.027).

DISCUSSION

KD might function as a surrogate parameter for comorbidity burden and thus increased risk of mortality in this cohort.

CONCLUSIONS

KD on admission is associated with an 80% higher risk of mortality at 90 days after stroke thrombectomy independent of cardiovascular risk factors and CKD awareness. KD on admission should not exclude patients from thrombectomy but might support prognostic evaluation.

Comparing Left Ventricular Structure and Functions in End-Stage Renal Disease Using Conventional Echocardiography and 2D Speckle Tracking Echocardiography

BACKGROUND

Patients on hemodialysis (HD) are prone to various cardiovascular complications. Two-dimensional speckle tracking echocardiography (2D STE) is an innovative technique for early myocardial dysfunction detection, even with normal ejection fraction (EF).

OBJECTIVE

We aim to detect left ventricle (LV) dysfunction in regular hemodialysis patients using 2D STE compared to traditional echocardiography.

METHODS

The study comprised 30 patients with end-stage renal disease (ESRD), subdivided according to left ventricular mass index (LVMI) into group 1 with left ventricular hypertrophy (LVH) (n=19) and group 2 without LVH (n=11). Another 30 healthy control subjects were recruited as group 3. The EF, average systolic velocity (Sa), and 2D LV strain were taken as measures of LV systolic function. The indicators for diastolic function included the E/A ratio and E velocity/peak early diastolic velocity.

RESULTS

Regarding the parameters of LV systolic and diastolic functions assessed by traditional echocardiography, we found no significant difference between groups 1 and 2. However, using 2D STE, we observed significant differences in the average Sa velocity (p=0.025), average LV strain (p=0.03), 2D global longitudinal strain (GLS) (p=0.03), E/Ea (p=0.003), and LV myocardial performance index (MPI) (p=0.006). Also, a significant positive correlation was found between LVMI and left ventricular end-diastolic diameter (LVEDD) (p<0.01, r=0.63), EF measured by 2D (p=0.034, r=0.39), mitral E/A ratio (p=0.03, r=0.49), and mitral E/Ea (p<0.01, r=0.72). There was a significantly strong negative correlation between LVMI and 2D average LV strain (p=0.034, r=-0.39).

CONCLUSION

We concluded that 2D STE is more sensitive than a conventional echo in detecting early LV systolic and diastolic dysfunction even in patients with normal EF.

The signaling pathways in obesity-related complications

Obesity, a rapidly expanding epidemic worldwide, is known to exacerbate many medical conditions, making it a significant factor in multiple diseases and their associated complications. This threatening epidemic is linked to various harmful conditions such as type 2 diabetes mellitus, hypertension, metabolic dysfunction-associated steatotic liver disease, polycystic ovary syndrome, cardiovascular diseases (CVDs), dyslipidemia, and cancer. The rise in urbanization and sedentary lifestyles creates an environment that fosters obesity, leading to both psychosocial and medical complications. To identify individuals at risk and ensure timely treatment, it is crucial to have a better understanding of the pathophysiology of obesity and its comorbidities. This comprehensive review highlights the relationship between obesity and obesity-associated complications, including type 2 diabetes, hypertension, (CVDs), dyslipidemia, polycystic ovary syndrome, metabolic dysfunction-associated steatotic liver disease, gastrointestinal complications, and obstructive sleep apnea. It also explores the potential mechanisms underlying these associations. A thorough analysis of the interplay between obesity and its associated complications is vital in developing effective therapeutic strategies to combat the exponential increase in global obesity rates and mitigate the deadly consequences of this polygenic condition.

Approach to weight management in patients with advanced chronic kidney disease in a real-life clinical setting

Objective

Excess adiposity represents a risk factor for chronic kidney disease (CKD) and progression to end-stage kidney disease. Anti-Obesity Medications (AOMs) are vastly underutilized in patients with advanced CKD because of concerns related to safety and efficacy. This study was conducted to evaluate the real-world approach to weight management and the efficacy and safety of AOMs in people with advanced CKD.

Methods

This is a retrospective analysis of individuals with Body Mass Index (BMI) ≥ 27 kg/m2 and eGFR ≤ 30 mL/min/1.73 m2 referred to an academic medical weight-management program between 01/2015 and 09/2022. Evaluation of weight-management approaches, body weight change, treatment-related side effects, and reasons for treatment discontinuation were reported.

Results

Eighty-nine patients met inclusion criteria, 16 were treated with intensive lifestyle modifications (ILM) alone and 73 with AOMs (all treated with glucagon-like peptide-1 receptor agonist [GLP1-RA] +/- other AOMs) along with ILM. Patients treated with AOMs had a longer duration of on-treatment follow-up (median 924 days) compared to (93 days) the ILM group. Over 75% of patients treated with AOMs lost ≥5% body weight versus 25% of those treated with ILM. Only 15% of patients treated with AOMs discontinued therapy due to treatment-related side effects.

Conclusion

In patients with obesity and advanced CKD, GLP-1RA-based anti-obesity treatment was well-tolerated, effective, and led to durable weight reduction.

Sex differences in the association of the uric acid to high-density lipoprotein cholesterol ratio with coronary artery disease risk among Chinese nondialysis patients with CKD stages 3-5

BACKGROUND AND AIMS

Evidence has indicated that serum uric acid (UA) and high-density lipoprotein cholesterol (HDL-C) are positively and negatively associated with coronary artery disease (CAD). The UA to HDL-C ratio (UHR) has recently drawn attention as a new predictor for metabolic syndrome, inflammation and atherosclerosis. However, the association between the UHR and CAD in nondialysis chronic kidney disease (CKD) patients is still unclear.

METHODS AND RESULTS

We retrospectively analysed 733 nondialysis patients with CKD stage 3-5 who received their first coronary artery angiography (CAG), including 510 participants with CAD. All laboratory indicators were collected within one week before CAG. The median UHR of CAD and non-CAD patients was 15.52% and 12.29%, respectively. In multivariate analysis, female patients with a high UHR were 4.7 times more at risk of CAD than those with a lower UHR. Meanwhile, the positive association of the UHR with the severity of coronary artery stenosis (CAS) persisted significantly in female CAD subjects but not in males. In addition, receiver operating characteristic (ROC) curves were constructed for CAD and severe CAS. The area under the curve (AUC) for the UHR was higher than that for UA and HDL-C alone in female patients [UHR (AUC): 0.715 for CAD and 0.716 for severe CAS].

CONCLUSIONS

An elevated UHR was independently related to an increased CAD risk and the severity of CAS in nondialysis female patients with CKD stage 3-5, and was more predictive of the onset of CAD and the severity of CAS than UA or HDL-C alone.

Impact of Ramadan fasting on lipid profile, uric acid, and HbA1c in CKD: A systematic review and meta-analysis

Studies have shown that fasting during Ramadan has different effects on circulating levels of several biochemical markers. This study aims to conduct a comprehensive evaluation of studies related to the effect of fasting in the holy month of Ramadan on lipid profile, uric acid, and HbA1c in CKD patients. Studies were systematically searched and collected from three databases (PubMed, Scopus, and Web of Science). After screening, the quality and risk of bias assessment of the selected articles were evaluated. Study heterogeneity was assessed using the Cochrane test and I² statistic. In case of any heterogeneity random effects model with the inverse-variance method was applied. All analyses were performed using STATA software version 16. Four observational studies were included in this study. The results of this meta-analysis were that cholesterol (Weighted mean differences (WMD):0.21 with 95% CI:-0.09-0.51 (P-value=:0.18)), LDL (WMD:0.06 with 95% CI -0.24-0.36 (P-value:0.69)), triglyceride (WMD:0.05 with 95% CI:-0.25-0.35 (P-value:0.73)) had not-significant increase. Uric acid (WMD: -0.11 with 95% CI: -0.42-0.21 (P-value:0.51)) and HbA1c (WMD: -0.22 with 95% CI: -0.79-0.36 (P-value: 0.46)) show a non-significant decrease. The results of the analyses did not report significant changes in the lipid profile, uric acid, and HbA1c in CKD patients after Ramadan fasting.

Galectin-3 in chronic kidney disease

BACKGROUND AND AIMS

High serum galectin-3 has been associated with adverse outcomes among dialysis patients, although its prognostic role remains unclear among individuals with earlier-stage chronic kidney disease. The present systematic review aims to evaluate the association of serum galectin-3 with survival, cardiovascular disease and kidney disease progression among non-dialysis chronic kidney disease patients.

METHODS

PubMed, Scopus, Web of Science, CENTRAL and Google Scholar were systematically searched till November 10, 2023. All observational studies assessing the prognostic role of serum galectin-3 in patients with non-dialysis chronic kidney disease were included.

RESULTS

Overall, 12 studies (10 cohort, 2 cross-sectional) were included, comprising 9,349 patients. The endpoint of survival was assessed in 5 studies, indicating a significant association between increasing serum galectin-3 levels and higher all-cause mortality risk (Hazard ratio per unit: 1.22, 95 % confidence intervals-CI: 1.05-1.41, ≥6 ng/mL: 2.66, 95 % CI: 1.68-4.23). Current evidence coming from 4 studies was inconclusive regarding the potential link of galectin-3 and kidney function decline, yielding conflicting results. No significant associations between serum galectin-3 and heart failure, cardiovascular events or death were consistently reported.

CONCLUSIONS

This systematic review supports the prognostic role of galectin-3 in chronic kidney disease, as its increased serum values may be associated with higher all-cause mortality risk. No clear role could be supported for serum galectin-3 regarding the prediction of cardiovascular disease or kidney disease progression.

Assessing Cognition in CKD Using the National Institutes of Health Toolbox

Key Points

Participants with CKD had detectable cognitive deficits in fluid cognition, dexterity, and total cognition. Sex differences in cognition exist in people with CKD.

Background

CKD is largely an age-related clinical disorder with accelerated cognitive and cardiovascular aging. Cognitive impairment is a well-documented occurrence in midlife and older adults with CKD and affects multiple domains. We examined cognition function and potential sex differences in cognition in adults with CKD.

Methods

We included 105 individuals (49.5% women) with CKD stage 3b–4 (eGFR, 15–44 ml/min) from the Bicarbonate Administration in CKD Trial (NCT02915601 ). We measured cognitive function using the National Institutes of Health Toolbox Cognition Battery, which assesses cognitive and motor measures, such as executive function, attention, memory, and dexterity. All study measures were collected and analyzed at the study baseline.

Results

The mean (SD) age and eGFR were 61±12 years and 34.9±9.8 ml/min per 1.73 m2. Overall, when compared with the National Institutes of Health Toolbox reference population, participants scored, on average, below the 50th percentile across all cognitive domain tests and the dexterity test. Total cognition scores were also below the 50th percentile. Participants with stage 4 CKD had significantly lower fluid cognition scores compared with those with CKD stage 3b (β -estimate −5.4 [95% confidence interval, −9.8 to −0.9]; P = 0.03). Female participants with CKD performed significantly better on the episodic memory tests and dexterity tests (dominant and nondominant pegboard tests) and had higher crystallized cognition scores, on average, compared with male participants.

Conclusions

Participants with CKD had detectable cognitive deficits in fluid cognition, dexterity, and total cognition. In addition, sex differences in cognitive measures were found among people with CKD.

Mediation effect of antithrombin III between chronic renal insufficiency and chronic coronary artery disease in T2DM patients

PURPOSE

The study aimed to investigate the potential effect of Antithrombin III (ATIII) between chronic renal insufficiency and chronic coronary artery disease (chronic CAD) in type 2 diabetes mellitus (T2DM) patients.

METHODS

T2DM patients hospitalized in ZhongDa Hospital from 2013 to 2018 were enrolled. Relationships between renal function, ATIII, and chronic CAD risk were explored using multivariate regression models. Multiplicative and additive interactions were investigated between ATIII and renal function for CAD risk, and the role of ATIII was determined by bootstrap mediation analysis in patients with chronic renal dysfunction.

RESULTS

A total of 4197 patients were included in the study, with a chronic CAD prevalence of 23.02%. Low ATIII level was statistically associated with chronic renal insufficiency and elevated CAD risk even after adjustments (P < 0.05). A positive correlation between renal function and ATIII was demonstrated, and each 1 SD increase in renal function, ATIII increased by 2.947% (2.406-3.488%, P < 0.001) and 0.969% (0.297-1.642%, P < 0.001) in crude and adjusted models respectively. Patients with decreased renal function and ATIII were at the highest chronic CAD risk (OR = 1.51, 95%CI:1.15-1.98, P < 0.05), while no multiplicative and additive interaction effects were significant. Bootstrap mediation analysis estimated that ATIII mediated approximately 4.27% of the effect of chronic renal insufficiency on chronic CAD risk.

CONCLUSION

ATIII may serve as a mediator between chronic renal insufficiency and chronic CAD, providing mechanistic clues for renal-heart association and new insight into clinical therapies.

24-h central pressure is a valuable predictor for left ventricular hypertrophy in non-dialysis patients with chronic kidney disease

The current research on the relationship between 24-h central pressure and 24-h brachial pressure with left ventricular hypertrophy (LVH) is characterised by limited sample size and inconsistent findings. Furthermore, the association has never been explored in chronic kidney disease (CKD). A multicentre, cross-sectional study among non-dialysis patients with CKD was conducted. All participants underwent brachial and central ambulatory blood pressure monitoring using MobilO-Graph PWA, while trained cardiologists performed echocardiography. In this study, 2117 non-dialysis patients with CKD were examined. 24-h central systolic blood pressure with c2 calibration (24-h c2SBP) demonstrated a stronger association with left ventricular mass index and LVH compared with 24-h brachial systolic blood pressure (24-h bSBP) in the univariate and multivariate regression analyses. The multivariate net reclassification index (NRI) analysis revealed that 24-h c2SBP exhibited greater discriminatory power over 24-h bSBP (NRI = 0.310, 95% CI [0.192-0.429], P < 0.001). Applying 130/135 mmHg as the threshold for 24-h bSBP/c2SBP to cross-classify, the patients were divided into concordant normotension (1509 individuals), isolated brachial hypertension (155 individuals), isolated central hypertension (11 individuals), and concordant hypertension (442 individuals). With concordant normotension as the reference, the multivariable-adjusted ORs were 0.954 (95% CI, 0.534-1.640; P = 0.870) for isolated brachial hypertension and 2.585 (95%CI, 1.841-3.633; P < 0.001) for concordant hypertension. Among non-dialysis patients with CKD, 24-h c2SBP exhibits greater efficacy in identifying the presence of LVH compared with 24-h bSBP. The presence of LVH was greater in cases of concordant hypertension compared with cases of isolated brachial hypertension and concordant normotension.

β,γ-Methylene-ATP and its metabolite medronic acid affect both arterial media calcification and bone mineralization in non-CKD and CKD rats

Arterial media calcification or pathological deposition of calcium-phosphate crystals in the vessel wall contributes significantly to the high mortality rate observed in patients with CKD. Extracellular nucleotides (ie, ATP or UTP) regulate the arterial calcification process by interacting with (1) purinergic receptors and (2) breakdown via ecto-nucleotidases, such as ectonucleotide pyrophosphatase/phosphodiesterase NPP1 or NPP3, affecting the local levels of calcification inhibitor, pyrophosphate, and stimulator inorganic phosphate (PPi/Pi ratio). Also, it has been shown that ATP analogs (ie, β,γ-methylene-ATP [β,γ-meATP]) inhibit vascular smooth muscle cell calcification in vitro. In the first experiment, daily dosing of β,γ-meATP (2 mg/kg) was investigated in rats fed a warfarin diet to trigger the development of non-CKD-related arterial medial calcifications. This study showed that β,γ-meATP significantly lowered the calcium scores in the aorta and peripheral vessels in warfarin-exposed rats. In a second experiment, daily dosing of 4 mg/kg β,γ-meATP and its metabolite medronic acid (MDP) was analyzed in rats fed an adenine diet to promote the development of CKD-related arterial medial calcification. Administration of β,γ-meATP and MDP did not significantly decrease aortic calcification scores in this model. Moreover, both compounds induced deleterious effects on physiological bone mineralization, causing an imminent risk for worsening the already compromised bone status in CKD. Due to this, it was not possible to raise the dosage of both compounds to tackle CKD-related arterial calcification. Again, this points out the difficult task of targeting solely ectopic calcifications without negatively affecting physiological bone mineralization. On the other hand, aortic mRNA expression of Enpp1 and Enpp3 was significantly and positively associated with aortic calcification scores, suggesting that normalizing the aortic NPP1/3 activity to control values might be a possible target to treat (CKD-induced) arterial media calcifications.

Dynamic natural components and morphological changes in nonculprit subclinical atherosclerosis in patients with acute coronary syndrome and mild chronic kidney disease at the 1-year follow-up and clinical significance at the 5-year follow-up

INTRODUCTION

The natural outcome of coronary plaque in acute coronary syndrome (ACS) patients with chronic kidney disease (CKD) is unique, which can be analyzed quantitatively by optical flow ratio (OFR) software.

METHODS

A total of 184 ACS patients with at least one nonculprit subclinical atherosclerosis (NSA) detected by optical coherence tomography (OCT) at baseline and 1-year follow-up were divided into non-CKD group (n = 106, estimated glomerular filtration rate (eGFR)> 90 mL/(min×1.73 m2)) and mild CKD group (n = 78, 60≤eGFR<90 mL/(min×1.73 m2)). Changes of normalized total atheroma volume (TAVn) of NSA was the primary endpoint at the 1-year follow-up.

RESULTS

Patients with mild CKD showed more TAVn progression of NSA than non-CKD (p = 0.019) from baseline to the 1-year follow-up, which was mainly due to an increase in calcium TAVn (p<0.001). The morphological change in the maximal calcification thickness (p = 0.026) was higher and the change in the distance from the calcified surface to the contralateral coronary media membrane (ΔC-to-M) at the maximal cross-sectional calcium area was lower (p<0.001) in mild CKD group than in non-CKD group. Mild CKD had more NSA related MACEs at the 5-year follow-up than non-CKD (30.8% vs. 5.8%, p = 0.045).

CONCLUSIONS

Mild CKD patients had more plaque progression of NSA which showed the increase of calcium component with more protrusion into the lumen morphologically at the 1-year follow-up and a higher corresponding incidence of NSA-related MACEs at the 5-year follow-up.

TRIAL REGISTRATION

Clinical Trial registration ClinicalTrials.gov. NCT02140801. https://classic.clinicaltrials.gov/ct2/show/NCT02140801.

Demographic trends of cardiorenal and heart failure deaths in the United States, 2011-2020

BACKGROUND

Heart failure (HF) and kidney disease frequently co-occur, increasing mortality risk. The cardiorenal syndrome results from damage to either the heart or kidney impacting the other organ. The epidemiology of cardiorenal syndrome among the general population is incompletely characterized and despite shared risk factors with HF, differences in mortality risk across key demographics have not been well described. Thus, the primary goal of this study was to analyze annual trends in cardiorenal-related mortality, evaluate if these trends differed by age, sex, and race or ethnicity, and describe these trends against a backdrop of HF mortality.

METHODS AND FINDINGS

The Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research database was used to examine cardiorenal- and HF-related mortality in the US between 2011and 2020. International Classification of Diseases, 10 Revision codes were used to classify cardiorenal-related deaths (I13.x) and HF-related deaths (I11.0, I13.0, I13.2, and I50.x), among decedents aged 15 years or older. Decedents were further stratified by age group, sex, race, or ethnicity. Crude and age-adjusted mortality rates (AAMR) per 100,000 persons were calculated. A total of 97,135 cardiorenal-related deaths and 3,453,655 HF-related deaths occurred. Cardiorenal-related mortality (AAMR, 3.26; 95% CI: 3.23-3.28) was significantly lower than HF-related mortality (AAMR, 115.7; 95% CI: 115.6-115.8). The annual percent change (APC) was greater and increased over time for cardiorenal-related mortality (2011-2015: APC, 7.1%; 95% CI: 0.7-13.9%; 2015-2020: APC, 19.7%, 95% CI: 16.3-23.2%), whereas HF-related mortality also increased over that time period, but at a consistently lower rate (2011-2020: APC, 2.4%; 95% CI: 1.7-3.1%). Mortality was highest among older and male decedents for both causes. Cardiorenal-related deaths were more common in non-Hispanic or Latino Blacks compared to Whites, but similar rates were observed for HF-related mortality. A larger proportion of cardiorenal-related deaths, compared to HF-related deaths, listed cardiorenal syndrome as the underlying cause of death (67.0% vs. 1.2%).

CONCLUSIONS

HF-related deaths substantially outnumber cardiorenal-related deaths; however, cardiorenal-related deaths are increasing at an alarming rate with the highest burden among non-Hispanic or Latino Blacks. Continued surveillance of cardiorenal-related mortality trends is critical and future studies that contain detailed biomarker and social determinants of health information are needed to identify mechanisms underlying differences in mortality trends.

Inhibition of Slc39a14/Slc39a8 reduce vascular calcification via alleviating iron overload induced ferroptosis in vascular smooth muscle cells

BACKGROUND

Vascular calcification (VC) is an independent risk factor for cardiovascular diseases. Recently, ferroptosis has been recognised as a novel therapeutic target for cardiovascular diseases. Although an association between ferroptosis and vascular calcification has been reported, the role and mechanism of iron overload in vascular calcification are still poorly understood. Specifically, further in-depth research is required on whether metalloproteins SLC39a14 and SLC39a8 are involved in ferroptosis induced by iron overload.

METHODS

R language was employed for the differential analysis of the dataset, revealing the correlation between ferroptosis and calcification. The experimental approaches encompassed both in vitro and in vivo studies, incorporating the use of iron chelators and models of iron overload. Additionally, gain- and loss-of-function experiments were conducted to investigate iron's effects on vascular calcification comprehensively. Electron microscopy, immunofluorescence, western blotting, and real-time polymerase chain reaction were used to elucidate how Slc39a14 and Slc39a8 mediate iron overload and promote calcification.

RESULTS

Ferroptosis was observed in conjunction with vascular calcification (VC); the association was consistently confirmed by in vitro and in vivo studies. Our results showed a positive correlation between iron overload in VSMCs and calcification. Iron chelators are effective in reversing VC and iron overload exacerbates this process. The expression levels of the metal transport proteins Slc39a14 and Slc39a8 were significantly upregulated during calcification; the inhibition of their expression alleviated VC. Conversely, Slc39a14 overexpression exacerbates calcification and promotes intracellular iron accumulation in VSMCs.

CONCLUSIONS

Our research demonstrates that iron overload occurs during VC, and that inhibition of Slc39a14 and Slc39a8 significantly relieves VC by intercepting iron overload-induced ferroptosis in VSMCs, providing new insights into the VC treatment.

Effects of Empagliflozin in Type 2 Diabetes With and Without Chronic Kidney Disease and Nondiabetic Chronic Kidney Disease: Protocol for 3 Crossover Randomized Controlled Trials (SiRENA Project)

BACKGROUND

Sodium-glucose-cotransporter 2 inhibitors (SGLT2is) have revolutionized the treatment of type 2 diabetes mellitus (DM2) and chronic kidney disease (CKD), reducing the risk of cardiovascular and renal end points by up to 40%. The underlying mechanisms are not fully understood.

OBJECTIVE

The study aims to examine the effects of empagliflozin versus placebo on renal hemodynamics, sodium balance, vascular function, and markers of the innate immune system in patients with DM2, DM2 and CKD, and nondiabetic CKD.

METHODS

We conducted 3 double-blind, crossover, randomized controlled trials, each with identical study protocols but different study populations. We included patients with DM2 and preserved kidney function (estimated glomerular filtration rate >60 mL/min/1.73 m2), DM2 and CKD, and nondiabetic CKD (both with estimated glomerular filtration rate 20-60 mL/min/1.73 m2). Each participant was randomly assigned to 4 weeks of treatment with either 10 mg of empagliflozin once daily or a matching placebo. After a wash-out period of at least 2 weeks, participants were crossed over to the opposite treatment. End points were measured at the end of each treatment period. The primary end point was renal blood flow measured with 82Rubidium positron emission tomography-computed tomography (82Rb-PET/CT). Secondary end points include glomerular filtration rate measured with 99mTechnetium-diethylene-triamine-pentaacetate (99mTc-DTPA) clearance, vascular function assessed by forearm venous occlusion strain gauge plethysmography, measurements of the nitric oxide (NO) system, water and sodium excretion, body composition measurements, and markers of the complement immune system.

RESULTS

Recruitment began in April 2021 and was completed in September 2022. Examinations were completed by December 2022. In total, 49 participants completed the project: 16 participants in the DM2 and preserved kidney function study, 17 participants in the DM2 and CKD study, and 16 participants in the nondiabetic CKD study. Data analysis is ongoing. Results are yet to be published.

CONCLUSIONS

This paper describes the rationale, design, and methods used in a project consisting of 3 double-blind, crossover, randomized controlled trials examining the effects of empagliflozin versus placebo in patients with DM2 with and without CKD and patients with nondiabetic CKD, respectively.

TRIAL REGISTRATION

EU Clinical Trials Register 2019-004303-12; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2019-004303-12, EU Clinical Trials Register 2019-004447-80; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2019-004447-80, EU Clinical Trials Register 2019-004467-50; https://www.clinicaltrialsregister.eu/ctr-search/search?query=and+2019-004467-50.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56067.

Oxygen venous saturation is associated with subclinical myocardial systolic dysfunction in patients with end-stage renal disease undergoing hemodialysis

Introduction

The aim of this prospective study was to evaluate the impact of hemodialysis (HD) on myocardial injury, of both right and left ventricle function as well as their association with venous oxygen saturation (ScvO2) alterations.

Material and methods

We included in the study stable consecutive patients with end-stage renal disease (ESRD) undergoing regular HD. Right and left ventricular speckle-tracking echocardiographies were performed in all patients. The examination calculates the global systolic longitudinal strain (GLS). Blood samples were obtained from the central vein in order to measure the O2 saturation (ScvO2) levels prior and post HD. High sensitive troponin (HST) was also measured in all patients before and after HD.

Results

Thirty seven patients were evaluated. We found that both mean ScvO2 and left ventricle GLS (LV GLS) were deteriorated after the dialysis session: 76.47 ±1.98 to 71.54 ±5.10, p < 0.05 and -17.73 ±3.44 to -14.21 ±3.44%, p < 0.01, respectively. HST levels were increased at the end of hemodialysis, 22.45 ±13.26 to 106.78 ±146.19 pg/ml, p < 0.01. A significant correlation was also found between the decrease of LV GLS with the ScvO2 reduction, p = 0.001, as well as with the increase of the HST levels, p = 0.001.

Conclusions

Our data demonstrate that there is a significant worsening of the GLS of the left ventricle at the end of the dialysis, which is strongly associated with the concomitant deterioration of ScvO2. The may be a reliable index of circulatory stress indicating a subclinical myocardial dysfunction during HD.

Triglyceride-Glucose Index Associated with Future Renal Function Decline in the General Population

BACKGROUND

The triglyceride-glucose index (TyG index), calculated as the logarithmic product of fasting triglyceride and glucose concentrations, is recognized as a simple marker of insulin resistance. However, the association between the TyG index and future decline of renal function remains unclear in the general population.

OBJECTIVE

To investigate whether the TyG index was associated with future decline of renal function in the general population who had not progressed to chronic kidney disease stage G2.

DESIGN

Retrospective longitudinal observational cohort study.

PARTICIPANTS

Individuals who received a population-based health checkup at JA Ehime Kouseiren Checkup Center from 2010 to 2019 (n = 134,007). Individuals without data of baseline fasting triglyceride or glucose levels, or baseline and follow-up data of estimated glomerular filtration rate (eGFR), or those with baseline eGFR < 60 mL/min/1.73 m2 were excluded.

MAIN MEASURES

Future renal function decline, defined as a ≥ 25% decrease in eGFR from baseline.

KEY RESULTS

Of 10,758 participants, 8,076 were classified into the low TyG index group (TyG index < 8.76, 1st to 3rd quartiles) and 2,682 into the high TyG index group (TyG index ≥ 8.76, 4th quartile). The mean follow-up period was 37.8 ± 23.6 months. The incidence rates of renal function decline were 0.31 and 0.69 per 100 person-years in the low and high TyG index groups, respectively. In multivariate Cox proportional hazard models, high TyG index was significantly associated with future renal function decline (hazard ratio 2.25, 95% CI 1.40-3.60). This association was consistent across subgroups stratified by age, sex, body mass index, baseline eGFR, and diagnosed hypertension, diabetes, or dyslipidemia.

CONCLUSION

In the general population, high TyG index was associated with future renal function decline. The TyG index may be useful in identifying individuals at high risk for future renal function decline in the setting of health checkups.

Acute kidney injury after out-of-hospital cardiac arrest

BACKGROUND

Acute kidney injury (AKI) is a significant risk factor associated with reduced survival following out-of-hospital cardiac arrest (OHCA). Whether the severity of AKI simply serves as a surrogate measure of worse peri-arrest conditions, or represents an additional risk to long-term survival remains unclear.

METHODS

This is a sub-study derived from a randomized trial in which 789 comatose adult OHCA patients with presumed cardiac cause and sustained return of spontaneous circulation (ROSC) were enrolled. Patients without prior dialysis dependent kidney disease and surviving at least 48 h were included (N = 759). AKI was defined by the kidney disease: improving global outcome (KDIGO) classification, and patients were divided into groups based on the development of AKI and the need for continuous kidney replacement therapy (CKRT), thus establishing three groups of patients-No AKI, AKI no CKRT, and AKI CKRT. Primary outcome was overall survival within 365 days after OHCA according to AKI group. Adjusted Cox proportional hazard models were used to assess overall survival within 365 days according to the three groups.

RESULTS

In the whole population, median age was 64 (54-73) years, 80% male, 90% of patients presented with shockable rhythm, and time to ROSC was median 18 (12-26) min. A total of 254 (33.5%) patients developed AKI according to the KDIGO definition, with 77 requiring CKRT and 177 without need for CKRT. AKI CKRT patients had longer time-to-ROSC and worse metabolic derangement at hospital admission. Overall survival within 365 days from OHCA decreased with the severity of kidney injury. Adjusted Cox regression analysis found that AKI, both with and without CKRT, was significantly associated with reduced overall survival up until 365 days, with comparable hazard ratios relative to no AKI (HR 1.75, 95% CI 1.13-2.70 vs. HR 1.76, 95% CI 1.30-2.39).

CONCLUSIONS

In comatose patients who had been resuscitated after OHCA, patients developing AKI, with or without initiation of CKRT, had a worse 1-year overall survival compared to non-AKI patients. This association remains statistically significant after adjusting for other peri-arrest risk factors.

TRIAL REGISTRATION

The BOX trial is registered at ClinicalTrials.gov: NCT03141099.

Advances in uremic toxin detection and monitoring in the management of chronic kidney disease progression to end-stage renal disease

Patients with end-stage kidney disease (ESKD) rely on dialysis to remove toxins and stay alive. However, hemodialysis alone is insufficient to completely remove all/major uremic toxins, resulting in the accumulation of specific toxins over time. The complexity of uremic toxins and their varying clearance rates across different dialysis modalities poses significant challenges, and innovative approaches such as microfluidics, biomarker discovery, and point-of-care testing are being investigated. This review explores recent advances in the qualitative and quantitative analysis of uremic toxins and highlights the use of innovative methods, particularly label-mediated and label-free surface-enhanced Raman spectroscopy, primarily for qualitative detection. The ability to analyze uremic toxins can optimize hemodialysis settings for more efficient toxin removal. Integration of multiple omics disciplines will also help identify biomarkers and understand the pathogenesis of ESKD, provide deeper understanding of uremic toxin profiling, and offer insights for improving hemodialysis programs. This review also highlights the importance of early detection and improved understanding of chronic kidney disease to improve patient outcomes.

Vitamin D: A Bridge between Kidney and Heart

Chronic kidney disease (CKD) and cardiovascular disease (CVD) are highly prevalent conditions, each significantly contributing to the global burden of morbidity and mortality. CVD and CKD share a great number of common risk factors, such as hypertension, diabetes, obesity, and smoking, among others. Their relationship extends beyond these factors, encompassing intricate interplay between the two systems. Within this complex network of pathophysiological processes, vitamin D has emerged as a potential linchpin, exerting influence over diverse physiological pathways implicated in both CKD and CVD. In recent years, scientific exploration has unveiled a close connection between these two prevalent conditions and vitamin D, a crucial hormone traditionally recognized for its role in bone health. This article aims to provide an extensive review of vitamin D's multifaceted and expanding actions concerning its involvement in CKD and CVD.

Effects of Cranberry Extract (Vaccinium macrocarpon) Supplementation on Lipid Peroxidation and Inflammation in Patients with Chronic Kidney Disease (Stages 3-4): A Randomized Controlled Trial

Background

Growing evidence suggests that bioactive compounds in berry fruits may mitigate inflammation in patients with chronic kidney disease (CKD).

Objectives

To evaluate cranberry (Vaccinium macrocarpon) supplementation effects on modulation of transcription factors involved in inflammation and oxidative stress in nondialysis (stages 3 and 4) patients with CKD. Design/Participants. A randomized, double-blind, placebo-controlled study was performed with 30 patients to receive capsules containing cranberry extract (1000 mg/day) or placebo (1000 mg/day of corn starch) for two months. Measurements. The mRNA expression of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor-kB (NF-kB) was evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time polymerase chain reaction. Thiobarbituric acid reactive substances (TBARS) were measured in the plasma to assess oxidative stress. Interleukin-6 (IL-6) plasma levels were assessed by enzyme-linked immunosorbent assay and C-reactive protein (CRP) by immunoturbidimetric method.

Results

Twenty-five patients completed the study: 12 in the cranberry group (56.7 ± 7.5 years and body mass index (BMI) of 29.6 ± 5.5 kg/m2) and 13 in the placebo group (58.8 ± 5.1 years and BMI 29.8 ± 5.4 kg/m2). There were no differences in NF-kB or Nrf2 mRNA expressions (p = 0.99 and p = 0.89) or TBARS, CRP, and IL-6 plasma levels after cranberry supplementation.

Conclusions

The cranberry extract administration (1000 mg/day) did not affect Nrf2 and NF-kB mRNA expression, oxidative stress, or inflammatory markers levels in nondialysis CKD patients. This trial is registered with NCT04377919.

The Prognostic Role of Serum β-Trace Protein Levels among Patients on Maintenance Hemodialysis

Cardiovascular (CV) diseases are the most commonly encountered etiology of mortality in patients having kidney failure. β-Trace protein (BTP) is a biomarker of glomerular filtration function as well as a potential predictor of adverse CV outcomes. This study aimed to determine the prognostic value of BTP in patients on chronic hemodialysis (HD). A total of 96 patients undergoing HD were enrolled. Baseline variables were collected, and the patients were tracked for 3 years. Twenty-five patients died at 3 years. Those who experienced mortality were noted to have higher serum concentrations of BTP and a higher incidence of diabetes mellitus (DM). The area under the receiver operating characteristic curve for serum BTP distinguishing mortality from survival was 0.659 (95% confidence interval [CI], 0.555-0.752; p = 0.027). After the adjustment of variables potentially affecting survival rates, BTP levels above the median (adjusted hazard ratio [aHR]: 2.913, 95% CI, 1.256-6.754; p = 0.013), the presence of DM (aHR: 2.474, 95% CI, 1.041-5.875; p = 0.040), and low serum albumin (aHR: 0.298, 95% CI, 0.110-0.806; p = 0.017) independently correlated with survival in HD patients. Serum BTP is a novel biomarker for predicting overall outcomes in HD patients.

Post-Transplant Cardiovascular Disease in Kidney Transplant Recipients: Incidence, Risk Factors, and Outcomes in the Era of Modern Immunosuppression

Introduction: Post-transplant cardiovascular disease (PTCVD) poses a significant challenge in kidney transplantation, potentially impacting graft outcomes and patient survival. This retrospective study aimed to investigate the incidence, risk factors, and consequential impact of PTCVD in kidney transplant recipients (KTRs) devoid of pre-existing cardiovascular disease (CVD). Method: The cohort comprised 1114 KTRs, with 749 individuals included after excluding those with pre-existing CVD and early graft loss. PTCVD encompasses ischemic heart disease, myocardial infarction, arrhythmias, heart failure, stroke, peripheral vascular disease, and valvular heart disease. Competing risk regression analysis was performed to identify predictors of PTCVD, while Cox proportional hazards analysis assessed the impact of PTCVD on graft and recipient survival. Results: The cumulative incidence of PTCVD at 5, 10, and 20 years was 5.4%, 14.3%, and 22.5%, respectively. Competing risk regression identified increased age (sub-hazard ratio [SHR], 1.22; p = 0.036) per decade, duration of dialysis (SHR, 1.07; p = 0.048) per year on dialysis, and the slope of the estimated glomerular filtration rate (SHR, 1.08; p = 0.008) mL/min/year decline as independent predictors of higher-risk PTCVD. A higher baseline estimated glomerular filtration rate (eGFR) was protective (SHR, 0.98; p = 0.032). PTCVD was not significantly associated with death-censored graft loss (adjusted hazard ratio [aHR] 1.31; p = 0.48) but was correlated with higher all-cause graft loss (aHR, 1.71; p = 0.011) and recipient mortality (aHR, 1.97; p = 0.004). Conclusion: This study provides insights into PTCVD predictors. Although not directly associated with graft loss, PTCVD significantly correlates with heightened mortality in kidney transplant recipients, emphasizing the need for enhanced clinical management and surveillance strategies.

Analysis of factors influencing vascular calcification in peritoneal dialysis patients and their impact on long-term prognosis

BACKGROUND

This study aims to investigate the influencing factors of vascular calcification in peritoneal dialysis (PD) patients and its relationship with long-term prognosis.

METHODS

This retrospective cohort study included chronic kidney disease patients undergoing peritoneal dialysis at the Peritoneal Dialysis Center of Beijing Luhu Hospital, Capital Medical University, from January 2019 to March 2019. Demographic and clinical laboratory data, including serum sclerostin (SOST), calcium (Ca), phosphate (P), serum albumin (ALB), and intact parathyroid hormone (iPTH) levels, were collected. Abdominal aortic calcification (AAC) was assessed using abdominal lateral X-ray examination to determine the occurrence of vascular calcification, and patients were divided into the AAC group and Non-AAC group based on the results.

RESULTS

A total of 91 patients were included in the study. The AAC group consisted of 46 patients, while the Non-AAC group consisted of 45 patients. The AAC group had significantly older patients compared to the non-AAC group (P < 0.001) and longer dialysis time (P = 0.004). Multivariable logistic regression analysis indicated that risk factors for vascular calcification in PD patients included dialysis time, diabetes, hypertension, and SOST. Kaplan-Meier survival analysis showed that the AAC group had a significantly higher mortality rate than the non-AAC group (χ2 = 35.993, P < 0.001). Multivariable Cox regression analysis revealed that dialysis time, diabetes and AAC were risk factors for all-cause mortality in peritoneal dialysis patients.

CONCLUSION

Longer dialysis time, comorbid diabetes, comorbid hypertension, and SOST are risk factors for vascular calcification in PD patients. Additionally, AAC, longer dialysis time, and comorbid diabetes are associated with increased risk of all-cause mortality in peritoneal dialysis patients.

Association of Tumor Necrosis Factor-Alpha (TNF-α) rs1800629 Polymorphism in Chronic Kidney Disease

Background Chronic kidney disease (CKD) is characterized by progressive loss of kidney function. Tumor necrosis factor-alpha (TNF-α) is a cytokine implicated in inflammatory processes, including those affecting the kidneys. Although this association is not yet comprehensible, a tie-up between renal disease and markers of inflammation - interleukin-6 (IL-6), preceded by TNF-α - is eminent. However, a pause in research is evident concerning the TNF-α gene with kidney disease in the inhabitants of India. So, this study investigates the association between TNF-α rs1800629 polymorphism and CKD. Methodology A prospective case-control study was conducted in Andhra Pradesh for over three years. A total of 579 patients participated in the study. These were divided into premature, late-stage CKD, and control groups. The amplification refractory mutation system (ARMS)-polymerase chain reaction (PCR) was used, and biochemical investigations and genotyping were carried out for the study participants. Hardy-Weinberg expected frequencies (HWE) with chi-square test was used for detecting allele and genotype frequencies. The association between TNF-α (-308 G/A, rs1800629) and CKD was assessed using odds ratios (ORs) with 95% confidence intervals (CIs). Results We found a higher prevalence of CKD among males (n = 301, 52%) compared to females (n = 278, 48%). Both male and female participants diagnosed with CKD exhibited significantly elevated blood urea and serum creatinine levels compared to the control group, indicating impaired kidney function. Furthermore, these markers were generally higher in the late-stage CKD group compared to the early-stage group, suggesting a progressive decline in kidney function as the disease worsens. The homozygous genotype GG was more prevalent in late-stage CKD patients compared to both early-stage CKD patients and controls. Further, the heterozygous genotype GA was more frequent in the early-stage CKD group compared to the late-stage group. The homozygous genotype AA also showed a higher prevalence in the early-stage CKD group compared to the late-stage group. The G/G genotype and the G allele (rs1800629) were significantly associated with susceptibility to CKD (P<0.005). Conclusions Our study reported the TNF-α rs1800629 polymorphism and CKD risk in a South Indian population. G/G genotype and the G allele (rs1800629) were significantly associated with the risk of CKD. However, further research with larger sample sizes is warranted to confirm these observations and elucidate the underlying mechanisms by which TNF-α might influence CKD risk.

Outcomes of peripheral artery disease and polyvascular disease in patients with end-stage kidney disease

OBJECTIVE

Patients with peripheral artery disease (PAD) and end-stage kidney disease are a high-risk population, and concomitant atherosclerosis in coronary arteries (CAD) or cerebral arteries (CVD) is common. The aim of the study was to assess long-term outcomes of PAD and the impact of coexistent CAD and CVD on outcomes.

METHODS

The United States Renal Data System was used to identify patients with PAD within 6 months of incident dialysis. Four groups were formed: PAD alone, PAD with CAD, PAD with CVD, and PAD with CAD and CVD. PAD-specific outcomes (chronic limb-threatening ischemia, major amputation, percutaneous/surgical revascularization, and their composite, defined as major adverse limb events [MALE]) as well as all-cause mortality, myocardial infarction, and stroke were studied.

RESULTS

The study included 106,567 patients (mean age, 71.2 years; 40.8% female) with a median follow-up of 546 days (interquartile range, 214-1096 days). Most patients had PAD and CAD (49.8%), 25.8% had PAD alone, and 19.2% had all three territories involved. MALE rate in patients with PAD was 22.3% and 35.0% at 1 and 3 years, respectively. In comparison to PAD alone, the coexistence of both CAD and CVD (ie, polyvascular disease) was associated with a higher adjusted rates of all-cause mortality (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.24-1.31), myocardial infarction (HR, 1.78; 95% CI, 1.69-1.88), stroke (HR, 1.66; 95% CI, 1.52,1.80), and MALE (HR, 1.07; 95% CI, 1.04-1.11).

CONCLUSIONS

Patients with end-stage kidney disease have a high burden of PAD with poor long-term outcomes, which worsen, in an incremental fashion, with the involvement of each additional diseased arterial bed.

PD-1 and LAG-3 positive T cells are related with the prognosis of patients with chronic kidney disease

OBJECTIVE

Our objective was to study the frequency of circulating LAG-3+ and PD-1+ T cells in chronic kidney disease (CKD) patients and their correlation with cytokines and patient prognosis.

METHODS

A total of 83 patients with CKD between June 2020 and June 2022 were enrolled. We measured serum levels of IL-6, CRP, IL-1β, and TNF-α by ELISA. The frequency of PD-1+ and LAG-3+ T cells was measured using flow cytometry. All patients were followed up for 1 year, and the occurrence of any of the following conditions during the follow-up period was considered as major adverse cardiac events (MACE) indicating poor prognosis.

RESULTS

The frequencies of LAG-3+PD-1+, LAG-3+ and PD-1+ cells were significantly increased in CKD group compared to healthy volunteers. Additionally, CKD patients had remarkably enhanced levels of cytokines. Compared to the non-MACE group, MACE group had significantly higher frequencies of LAG-3PD-1, LAG-3 and PD-1 expression on CD8 and CD4. Positive correlations were observed between IL-1β, IL-6 and frequencies of PD-1+LAG-3+. CD4+LAG-3+PD-1+ frequency displayed the highest diagnostic value for CKD patients with MACE. Moreover, CD8+LAG-3+, CD4+LAG-3+PD-1+, CD4+PD-1+, IL-1β and IL-6 were identified as risk factors for the occurrence of MACE in patients with CKD.

CONCLUSION

In summary, the present research showed that the frequencies of LAG-3+ and PD-1+ T cells were remarkably enhanced in CKD patients. These findings offer novel insights and potential therapeutic targets for the management of CKD.

[Mortality trends in Germany in an international context]

BACKGROUND AND AIM

Due to its strong economy and a well-developed healthcare system, Germany is well positioned to achieve above-average reductions in mortality. Nevertheless, in terms of life expectancy, Germany is increasingly falling behind Western Europe. We compare mortality trends in Germany with other Western European countries, covering the period from 1960 to 2019. The focus is on long-term trends in Germany's ranking in international mortality trends. In addition, we conduct a detailed mortality analysis by age.

METHODS

Our analysis is mostly based on mortality data from the Human Mortality Database (HMD). Cause-specific mortality data originate from the database of the World Health Organization (WHO). For the international comparison of mortality trends, we use conventional mortality indicators (age-standardized mortality rate, period life expectancy).

RESULTS

Compared to other Western European countries, Germany has higher mortality in the middle and older age groups. Germany's life expectancy gap compared to Western Europe has grown during the past 20 years. In 2000, Germany was 0.73 years behind for men and 0.74 years behind for women. By 2019, these figures had risen to 1.43 and 1.34 years, respectively. This is mainly due to mortality from non-communicable diseases.

CONCLUSION

For Germany to catch up with other Western European countries, a stronger focus on further reducing mortality at ages 50+ is crucial. This also requires further research to understand the factors behind Germany's disadvantageous position.

Resting strain analysis to identify myocardial ischemia in patients with advanced chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is associated with higher incidence of cardiovascular death. Screening for coronary artery disease in asymptomatic or mildly symptomatic patients is challenging.

OBJECTIVE

The aim of this study was to investigate the incremental value of resting deformation analysis in predicting positive results for myocardial ischemia during stress transthoracic echocardiography in patients with end-stage CKD.

METHODS

Sixty-one patients (mean age: 62.3 ± 11.8, 65.7% men) with end-stage CKD were included in the study. Patients underwent a resting transthoracic echocardiogram and a dobutamine stress contrast echo (DSE) protocol. Positive results of DSE were defined as stress-induced left ventricular (LV) wall motion abnormalities.

RESULTS

The study cohort had normal or mildly impaired systolic function: mean LV ejection fraction (EF) was 49.2% (±10.4) and mean LV global longitudinal strain (GLS) was 14.4% (±4.5). Half of our population had impaired left atrial (LA) strain: mean LA reservoir, conduit, and contractile reserve were 24.1% (±12.6), 10.6% (±5.9), and 13.6% (±9.2), respectively. DSE was positive for ischemia in 55.7%. A significant negative association with DSE results was found for LV EF, LV GLS and the conduit phase of LA strain. Both LV and LA dimensions showed positive correlation with presence of ischemia in DSE. Multivariate logistic regression analysis showed that LV GLS was independently associated with DSE (p = 0.007), after controlling for covariates, with high diagnostic accuracy.

CONCLUSION

Resting LV deformation could predict positive results during DSE, thus may be useful to better identify renal patients who might benefit from coronary artery screening.

Long-term health outcomes associated with hydration status

Body water balance is determined by fundamental homeostatic mechanisms that maintain stable volume, osmolality and the composition of extracellular and intracellular fluids. Water balance is maintained by multiple mechanisms that continuously match water losses through urine, the skin, the gastrointestinal tract and respiration with water gains achieved through drinking, eating and metabolic water production. Hydration status is determined by the state of the water balance. Underhydration occurs when a decrease in body water availability, due to high losses or low gains, stimulates adaptive responses within the water balance network that are aimed at decreasing losses and increasing gains. This stimulation is also accompanied by cardiovascular adjustments. Epidemiological and experimental studies have linked markers of low fluid intake and underhydration - such as increased plasma concentration of vasopressin and sodium, as well as elevated urine osmolality - with an increased risk of new-onset chronic diseases, accelerated aging and premature mortality, suggesting that persistent activation of adaptive responses may be detrimental to long-term health outcomes. The causative nature of these associations is currently being tested in interventional trials. Understanding of the physiological responses to underhydration may help to identify possible mechanisms that underlie potential adverse, long-term effects of underhydration and inform future research to develop preventative and treatment approaches to the optimization of hydration status.

Serotonin regulation of mitochondria in kidney diseases

Serotonin, while conventionally recognized as a neurotransmitter in the CNS, has recently gained attention for its role in the kidney. Specifically, serotonin is not only synthesized in the kidney, but it also regulates glomerular function, vascular resistance, and mitochondrial homeostasis. Because of serotonin's importance to mitochondrial health, this review is focused on the role of serotonin and its receptors in mitochondrial function in the context of acute kidney injury, chronic kidney disease, and diabetic kidney disease, all of which are characterized by mitochondrial dysfunction and none of which has approved pharmacological treatments. Evidence indicates that activation of certain serotonin receptors can stimulate mitochondrial biogenesis (MB) and restore mitochondrial homeostasis, resulting in improved renal function. Serotonin receptor agonists that induce MB are therefore of interest as potential therapeutic strategies for renal injury and disease. SIGNIFICANCE STATEMENT: Mitochondrial dysfunction is associated with many human renal diseases such as acute kidney injury, chronic kidney disease, and diabetic kidney disease, which are associated with increased morbidity and mortality. Unfortunately, none of these pathologies has an FDA-approved pharmacological intervention, underscoring the urgency of identifying new therapeutics for such disorders. Studies show that induction of mitochondrial biogenesis via serotonin (5-hydroxytryptamine, 5-HT) receptors reduces kidney injury markers, restores mitochondrial and renal function after kidney injury, and decreases mortality, suggesting that targeting 5-HT receptors may be a promising therapeutic avenue for mitochondrial dysfunction in kidney diseases. While numerous reviews describe the importance of mitochondria and mitochondrial quality control mechanisms in kidney disease, the relevance of 5-HT receptor-mediated mitochondrial metabolic modulation in the kidney has yet to be thoroughly explored.

Daprodustat and Heart Failure in CKD

Key Points

Patients with CKD face meaningful risk of heart failure hospitalization. Daprodustat compared with darbepoetin was associated with a nonsignificantly greater number of heart failure hospitalizations in non-dialysis patients.

Background

Patients with CKD are at higher risk of heart failure. The hypoxia-inducible factor prolyl hydroxylase inhibitor daprodustat is an orally acting alternative to conventional injectable erythropoietin-stimulating agents (ESAs) for the treatment of anemia in patients with CKD. Whether daprodustat affects the risk of heart failure hospitalization is unknown.

Methods

The Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat–Dialysis (ASCEND-D; n =2964) and Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat–Non-Dialysis (ASCEND-ND; n =3872) trials compared daprodustat with conventional ESA in patients with anemia of CKD who did or did not require dialysis, respectively. We identified risk factors of heart failure hospitalization and assessed the effect of daprodustat compared with conventional ESA on heart failure hospitalizations.

Results

History of heart failure, diabetes, and higher systolic BP were independently associated with heart failure hospitalization in both trials, irrespective of treatment assignment. The number of first heart failure hospitalizations was greater in the daprodustat arm in patients not receiving dialysis (hazard ratio [HR], 1.22 [95% confidence interval (CI), 0.95 to 1.56], P = 0.12) and in patients receiving dialysis (HR, 1.10 [95% CI, 0.84 to 1.45], P = 0.47), although these differences were not statistically significant. HRs in patients with and without history of heart failure were 1.37 (95% CI, 0.89 to 2.11) versus 1.08 (95% CI, 0.79 to 1.46) (P -interaction=0.36) in the ASCEND-ND trial and 1.52 (95% CI, 0.97 to 2.38) versus 0.93 (95% CI, 0.66 to 1.30) (P -interaction=0.09) in the ASCEND-D trial, respectively. In post hoc analyses, daprodustat increased total (first and recurrent) heart failure hospitalizations in participants not receiving dialysis (rate ratio, 1.46 [95% CI, 1.11 to 1.92], P = 0.007) but not in participants receiving dialysis (rate ratio, 1.01 [95% CI, 0.74 to 1.39], P = 0.93). Daprodustat did not significantly affect the risk of a composite outcome of first heart failure hospitalization or death.

Conclusions

A greater number of first heart failure hospitalization events occurred in patients treated with daprodustat compared with conventional ESA, but this difference did not reach statistical significance. Differences in the number of heart failure hospitalization events were most apparent in patients not receiving dialysis and in patients with history of heart failure.

Podcast

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2024_04_10_ASN0000000000000321.mp3

Clinical outcomes following discontinuation of metformin in patients with type 2 diabetes and advanced chronic kidney disease in Hong Kong: a territory-wide, retrospective cohort and target trial emulation study

Background

Current labelling advises discontinuation of metformin when estimated glomerular filtration rate (eGFR) < 30 ml/min/1.73 m2 due to increased risk of lactic acidosis. However, in real-world practice, the risk-benefit ratios remain uncertain. We examined the risk associations of discontinued-metformin use with cardiorenal and clinical outcomes in patients with type 2 diabetes (T2D) and advanced chronic kidney disease.

Methods

In this territory-wide, retrospective cohort and target trial emulation study, we included Chinese patients attending the Hong Kong Hospital Authority (HA) and enrolled in the Risk-Assessment-and-Management-Programme-for-Diabetes-Mellitus (RAMP-DM) from 2002 to 2019. Patients were stratified by discontinuation of metformin within six months after reaching eGFR < 30 ml/min/1.73 m2 from January 1, 2002 to December 31, 2018, and followed up until December 31 2019. We excluded patients who had observational time <6 months from eGFR < 30 ml/min/1.73 m2, and had their eGFR measured during a hospitalisation episode due to acute kidney injury, or missing diagnosis date of diabetes. We compared the risk associations of metformin discontinuation with clinical outcomes. The primary outcomes were major adverse cardiovascular events (MACE), end-stage kidney disease (ESKD), cancer, and all-cause mortality. A Cox-model with time-dependent exposure and covariates was used to estimate the hazard ratio (HR) of outcomes in a propensity-score overlap-weighted cohort. The risk of occurrence of lactic acidosis (serum lactate > 5.0 mmol/L with a concomitant blood pH < 7.35 or ICD-9 codes of 276.2) in discontinued-metformin versus continued-metformin users was assessed in a separate register-based cohort.

Findings

A total of 33,586 metformin users with new-onset eGFR < 30 ml/min/1.73 m2 were included in the study, 7500 (22.3%) of whom discontinued metformin within 6 months whereas 26,086 (77.7%) continued use of metformin. During a median follow-up of 3.8 (IQR: 2.2-6.1) years, 16.4% (5505/33,586), 30.1% (10,113/33,586), and 7.1% (2171/30,682) had incident MACE, ESKD, and cancer respectively, and 44.4% (14,917/33,586) died. Compared to continued-metformin use, discontinuation was associated with higher risk of MACE (weighted and adjusted HR = 1.40, 95% CI: 1.29-1.52), ESKD (HR = 1.52, 1.42-1.62), and death (HR = 1.22, 1.18-1.27). No association was observed for cancer (HR = 0.93, 0.85-1.01). Discontinued-metformin users had higher change in HbA1c change at 6-month of follow-up versus continued-metformin users (weighted mean HbA1c level change: 0.5% [0.4-0.6%] versus 0.2% [0.1-0.2]). In the separate register-based cohort (n = 3235), null association was observed between metformin use and risk of lactic acidosis (weighted HR = 0.94 [0.53-1.64]).

Interpretation

Our results suggest that discontinuation of metformin in patients with T2D and chronic kidney disease may be associated with increased risk of cardiovascular-renal events. Use of metformin below eGFR of 30 ml/min/1.73 m2 may be associated with cardiovascular, renal, and mortality benefits that need to be weighed against the risk of lactic acidosis, but further research is needed to validate these findings.

Funding

CUHK Impact Research Fellowship Scheme.

Dietary cholesterol intake is not associated with the development of chronic kidney disease: Results from two Korean cohort studies

BACKGROUND AND AIMS

Although dyslipidemia is a major risk factor for chronic kidney disease (CKD), the relationship between dietary cholesterol and CKD remains unknown. We investigated the association between cholesterol intake and CKD risk.

METHODS AND RESULTS

The Korea National Health and Nutrition Examination Survey (KNHANES) 2019-2021 (n = 13,769) and the Korean Genome and Epidemiology Study (KoGES) (n = 9225) data were used for this study. Cholesterol intake was assessed using a 24-h recall food frequency questionnaire, and participants were categorized into three groups (T1, T2, and T3) based on cholesterol intake. Primary outcomes were prevalence and incidence of CKD. Higher cholesterol intake was modestly associated with increased serum levels of total, low-density lipoprotein, and high-density lipoprotein cholesterol in the KNHANES. However, we found no significant association between cholesterol intake and CKD prevalence in the KNHANES, regardless of a history of hypercholesterolemia. In the KoGES, during a median follow-up of 11.4 years, cholesterol intake was not associated with incident CKD in participants without hypercholesterolemia (hazard ratio [HR] per 10 mg increase, 1.00; 95 % confidence interval [CI], 0.99-1.01) and in those with hypercholesterolemia (HR, 1.01; 95 % CI, 0.98-1.04). Egg consumption also showed no significant association with the risk of incident CKD. Additionally, cholesterol intake had no significant interaction on the relationships between serum cholesterol levels and incident CKD.

CONCLUSION

Although cholesterol intake was associated with increased serum cholesterol levels, it was not associated with CKD prevalence and incidence. Our findings suggest that reducing cholesterol intake alone may not be sufficient to prevent CKD.

Effect of HCV eradication by DAAs on liver steatosis, carotid atherosclerosis, and associated metabolic comorbidities: A systematic review

BACKGROUND AND AIMS

The beneficial effect of Hepatitis C virus (HCV) eradication by direct antiviral agents (DAAs) on liver fibrosis is well defined. Despite this, the impact of viral eradication in both hepatic and extra-hepatic metabolic features is underreached. This systematic review aimed to synthesize the evidence on the impact of HCV eradication by DAAs on liver steatosis, carotid atherosclerosis, glucidic impairment, dyslipidaemia, and weight gain.

METHODS

A systematic search of the existing literature (up to December 2022) identified 97 original studies that fulfilled the inclusion criteria.

RESULTS

Whereas total cholesterol and low-density lipoprotein (LDL) seem to increase after viral eradication, the cardiovascular damage expressed as carotid plaques and intima-media thickness seems to improve. Otherwise, the effect on liver steatosis, glucidic homeostasis, and weight seems to be strictly dependent on the presence of baseline metabolic disorders.

CONCLUSION

Despite high heterogeneity and relatively short follow-up of included studies, we can conclude that the presence of metabolic risk factors should be strictly evaluated due to their impact on liver steatosis, glucidic and lipid homeostasis, and on weight gain to better identify patients at risk of liver disease progression despite the virus eradication.

Prognostic utility of rhythmic components in 24-h ambulatory blood pressure monitoring for the risk stratification of chronic kidney disease patients with cardiovascular co-morbidity

Chronic kidney disease (CKD) represents a significant global burden. Hypertension is a modifiable risk factor for rapid progression of CKD. We extend the risk stratification by introducing the non-parametric determination of rhythmic components in 24-h profiles of ambulatory blood pressure monitoring (ABPM) in the Chronic Renal Insufficiency Cohort (CRIC) and the African American Study for Kidney Disease and Hypertension (AASK) cohort using Cox proportional hazards models. We find that rhythmic profiling of BP through JTK_CYCLE analysis identifies subgroups of CRIC participants that were more likely to die due to cardiovascular causes. While our fully adjusted model shows a trend towards a significant association between absent cyclic components and cardiovascular death in the full CRIC cohort (HR: 1.71,95% CI: 0.99-2.97, p = 0.056), CRIC participants with a history of cardiovascular disease (CVD) and absent cyclic components in their BP profile had at any time a 3.4-times higher risk of cardiovascular death than CVD patients with cyclic components present in their BP profile (HR: 3.37, 95% CI: 1.45-7.87, p = 0.005). This increased risk was not explained by the dipping or non-dipping pattern in ABPM. Due to the large differences in patient characteristics, the results do not replicate in the AASK cohort. This study suggests rhythmic blood pressure components as a potential novel biomarker to unmask excess risk among CKD patients with prior cardiovascular disease.

Chronic kidney disease and left ventricular diastolic dysfunction (CKD-LVDD) alter cardiac expression of mitochondria-related genes in swine

Cardiovascular disease and heart failure doubles in patients with chronic kidney disease (CKD), but the underlying mechanisms remain obscure. Mitochondria are central to maintaining cellular respiration and modulating cardiomyocyte function. We took advantage of our novel swine model of CKD and left ventricular diastolic dysfunction (CKD-LVDD) to investigate the expression of mitochondria-related genes and potential mechanisms regulating their expression. CKD-LVDD and normal control pigs (n=6/group, 3 males/3 females) were studied for 14 weeks. Renal and cardiac hemodynamics were quantified by multidetector-CT, echocardiography, and pressure-volume loop studies, respectively. Mitochondrial morphology (electron microscopy) and function (Oroboros) were assessed ex vivo. In randomly selected pigs (n=3/group), cardiac mRNA-, MeDIP-, and miRNA-sequencing (seq) were performed to identify mitochondria-related genes and study their pre- and post -transcriptional regulation. CKD-LVDD exhibited cardiac mitochondrial structural abnormalities and elevated mitochondrial H2O2 emission but preserved mitochondrial function. Cardiac mRNA-seq identified 862 mitochondria-related genes, of which 69 were upregulated and 33 downregulated (fold-change ≥2, false discovery rate≤0.05). Functional analysis showed that upregulated genes were primarily implicated in processes associated with oxidative stress, whereas those downregulated mainly participated in respiration and ATP synthesis. Integrated mRNA/miRNA/MeDIP-seq analysis showed that upregulated genes were modulated predominantly by miRNAs, whereas those downregulated were by miRNA and epigenetic mechanisms. CKD-LVDD alters cardiac expression of mitochondria-related genes, associated with mitochondrial structural damage but preserved respiratory function, possibly reflecting intrinsic compensatory mechanisms. Our findings may guide the development of early interventions at stages of cardiac dysfunction in which mitochondrial injury could be prevented, and the development of LVDD ameliorated.

SNF472: a novel therapeutic agent for vascular calcification and calciphylaxis

Vascular calcification is a common complication in patients with chronic kidney disease (CKD) and is strongly associated with an increased risk of cardiovascular events and all-cause mortality. Calciphylaxis is a specific and life-threatening manifestation of vascular calcifications that usually affects individuals with advanced kidney function impairment or those undergoing dialysis. Currently, the treatment of vascular calcification and calciphylaxis in CKD lacks approved treatments and focuses on controlling risk factors. SNF472, the intravenous formulation of myo-inositol hexaphosphate, is a novel vascular calcification inhibitor currently undergoing phase 3 clinical trials, demonstrating its ability to directly inhibit the formation of calcium and phosphorus crystals, thereby blocking the production and deposition of ectopic calcium. The efficacy and safety of SNF472 in inhibiting vascular calcification have been confirmed in recent clinical studies. This review summarizes the results of studies related to SNF472 to provide a comprehensive overview of its mechanism of action, efficacy, safety, and ongoing clinical studies.

The current use of proteomics and metabolomics in glomerulonephritis: a systematic literature review

BACKGROUND

Glomerulonephritis inherently leads to the development of chronic kidney disease. It is the second most common diagnosis in patients requiring renal replacement therapy in the United Kingdom. Metabolomics and proteomics can characterise, identify and quantify an individual's protein and metabolite make-up. These techniques have been optimised and can be performed on samples including kidney tissue, blood and urine. Utilising omic techniques in nephrology can uncover disease pathophysiology and transform the diagnostics and treatment options for glomerulonephritis.

OBJECTIVES

To evaluate the utility of metabolomics and proteomics using mass spectrometry and nuclear magnetic resonance in glomerulonephritis.

METHODS

The systematic review was registered on PROSPERO (CRD42023442092). Standard and extensive Cochrane search methods were used. The latest search date was March 2023. Participants were of any age with a histological diagnosis of glomerulonephritis. Descriptive analysis was performed, and data presented in tabular form. An area under the curve or p-value was presented for potential biomarkers discovered.

RESULTS

Twenty-seven studies were included (metabolomics (n = 9)), and (proteomics (n = 18)) with 1818 participants. The samples analysed were urine (n = 19) blood (n = 4) and biopsy (n = 6). The typical outcome themes were potential biomarkers, disease phenotype, risk of progression and treatment response.

CONCLUSION

This review shows the potential of metabolomic and proteomic analysis to discover new disease biomarkers that may influence diagnostics and disease management. Further larger-scale research is required to establish the validity of the study outcomes, including the several proposed biomarkers.