Comparison of cardiovascular mortality in hemodialysis versus peritoneal dialysis

Characteristics of patients and facility of peritoneal dialysis in Korea: Results from the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) Korea

BACKGROUND

Varying peritoneal dialysis (PD)-related clinical outcomes have been reported in different countries. As a participant of the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS), this study investigated the characteristics of Korean PD patients, PD facilities and the incidence rates of clinical outcomes including mortality and PD-related outcomes.

METHODS

From July 2019 to December 2021, a total of 766 Korean PD patients were included for analysis. Poisson regression analysis was used to explore the incidence rates of various clinical events including mortality, modality transfer, exit site or catheter tunnel infection and peritonitis.

RESULTS

Among the 766 patients (median age 55.5 years, males 59.5%), 276 were incident and 490 were prevalent PD patients. The incidence rates of events were as follows: all-cause mortality (0.048), modality transfer (0.051), exit site or catheter tunnel infection (0.054) and peritonitis (0.136) events per person year. The most common causative organism for exit site or tunnel infection was staphylococcus species (47%) and that for peritonitis was streptococcus (28%) followed by staphylococcus (27%) species.

CONCLUSIONS

Up to now, PDOPPS Korea has recruited 766 Korean PD patients and started documentation of major PD-related outcomes which occurred during the follow-up period. The overall incidence rates of clinical outcomes in Korean PD patients were relatively favourable. There was no statistically significant difference in the incidence rates of clinical outcomes according to both facility and patient factors.

The association of peritoneal dialysis and hemodialysis on mitral and aortic valve calcification associated mortality: a meta-analysis

Cardiac valve calcification (CVC), characterized by the accumulation of calcium in the heart valves, is highly prevalent among patients undergoing dialysis. This meta-analysis aimed to provide an updated summary of recent studies on the prognostic value of CVC in patients undergoing dialysis. We conducted a search of PubMed, Embase, and Web of Science to identify observational studies investigating cardiovascular or all-cause mortality associated with CVC in dialysis patients until March 2023. Hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were calculated for the meta-analysis, and the strength and significance of the associations between CVC and mortality outcomes in dialysis patients were assessed. From 6218 initially identified studies, we included 10 critical studies with a total of 3376 dialysis patients in a further meta-analysis. Pooled analyses demonstrated a significant association between CVC and an elevated risk of all-cause and cardiovascular mortality in dialysis patients. In our study, we discovered HRs of 1.592 (95% CI 1.410-1.797) for all-cause mortality and 2.444 (95% CI 1.632-3.659) for cardiovascular mortality. Furthermore, subgroup analysis revealed elevated all-cause mortality among patients with mitral valve calcification (HR 1.572; 95% CI 1.200-2.060) compared to those with aortic valve calcification (HR 1.456; 95% CI 1.105-1.917). Similarly, patients undergoing peritoneal dialysis faced a greater risk for all-cause mortality (HR 2.094; 95% CI 1.374-3.191) than those on hemodialysis (HR 1.553; 95% CI 1.369-1.763). This highlights the possibility of CVC being an independent risk factor for dialysis patients, particularly in relation to mitral valve calcification or peritoneal dialysis.

Novel Perspectives in Chronic Kidney Disease-Specific Cardiovascular Disease

Chronic kidney disease (CKD) affects > 10% of the global adult population and significantly increases the risk of cardiovascular disease (CVD), which remains the leading cause of death in this population. The development and progression of CVD-compared to the general population-is premature and accelerated, manifesting as coronary artery disease, heart failure, arrhythmias, and sudden cardiac death. CKD and CV disease combine to cause multimorbid cardiorenal syndrome (CRS) due to contributions from shared risk factors, including systolic hypertension, diabetes mellitus, obesity, and dyslipidemia. Additional neurohormonal activation, innate immunity, and inflammation contribute to progressive cardiac and renal deterioration, reflecting the strong bidirectional interaction between these organ systems. A shared molecular pathophysiology-including inflammation, oxidative stress, senescence, and hemodynamic fluctuations characterise all types of CRS. This review highlights the evolving paradigm and recent advances in our understanding of the molecular biology of CRS, outlining the potential for disease-specific therapies and biomarker disease detection.

Atherogenic index predicts all-cause and cardiovascular mortality in incident peritoneal dialysis patients

BACKGROUND AND AIMS

Atherosclerosis, the main cause of cardiovascular disease (CVD), is prevalent in patients undergoing peritoneal dialysis (PD). Atherogenic index (AI) is a strong predictor of atherosclerosis. However, its prognostic value in CVD outcomes and all-cause mortality among patients undergoing PD remains uncertain. Therefore, we aimed to evaluate the association between AI and all-cause and CVD mortality in PD patients.

METHODS

Calculated based on lipid profiles obtained through standard laboratory procedures, AI was evaluated in 2682 patients who underwent PD therapy between January 2006 and December 2017 and were followed up until December 2018. The study population was divided into four groups according to the quartile distribution of AI (Q1: <2.20, Q2: 2.20 to <2.97, Q3: 2.97 to <4.04, and Q4: ≥4.04). Multivariable Cox models were employed to explore the associations between AI and CVD and all-cause mortality was evaluated.

RESULTS

During a median follow-up of 35.5 months (interquartile range, 20.9-57.2 months), 800 patients died, including 416 deaths from CVD. Restricted cubic splines showed non-linear relationship between AI and adverse clinical outcomes. The risks of all-cause and CVD mortality gradually increased across quartiles (log-rank, p < 0.001). After adjusting for potential confounders, the highest quartile (Q4) showed significantly elevated hazard ratio (HR) for both all-cause mortality (HR 1.54 [95% confidence interval (CI), 1.21-1.96]) and CVD mortality risk (HR 1.78 [95% CI, 1.26-2.52]), compared to the lowest quartile (Q1).

CONCLUSIONS

AI was independently associated with all-cause and CVD mortality in patients undergoing PD, suggesting that AI might be a useful prognostic marker.

Volume markers in left ventricular diastolic dysfunction and adverse outcomes in peritoneal dialysis patients: a prospective cohort study

Left ventricular diastolic dysfunction (LVDD) is an early event associated with cardiovascular complications and poor prognosis in chronic kidney disease patients undergoing dialysis. In this study, we investigated whether diastolic dysfunction, measured by the E/E' ratio, affects adverse outcomes in peritoneal dialysis (PD) patients (n = 148). Our results showed that patients with an E/E' ratio ≥ 15 were more likely to be female, have a longer dialysis vintage, have significantly higher left atrial volume index and left atrial kinetic energy levels, have lower E' levels and LV hypertrophy (LVH) degree, and have higher volume markers. Kaplan-Meier curves revealed that patients with a higher E/E' ratio had worse survival and a higher risk of heart failure than those with a lower E/E' ratio. Subgroup analysis demonstrated that non-diabetic patients with a higher E/E' ratio had a higher risk of heart failure than those with a lower E/E' ratio. Cox proportional hazard regression analysis indicated that the ECW/ICW ratio was strongly associated with LVDD and confirmed that the E/E' ratio was an independent risk factor for overall death. Our study suggests that monitoring the E/E' ratio in PD patients is important for improving their prognosis.

Progress in the application of the neutrophil-to-lymphocyte ratio in dialysis-related complications

The neutrophil-to-lymphocyte ratio (NLR) is a novel predictive biomarker that reflects systemic inflammatory status and is routinely measured in blood tests. Owing to its ease of use and affordability, it is being increasing used as a prognostic indicator of cardiovascular disease, tumors, autoimmune disorders, and kidney disease. In recent years, a number of studies have demonstrated the clinical utility of the NLR in identifying and predicting complications associated with hemodialysis and peritoneal dialysis, including cardiovascular disease and infection. This review aimed to provide a new perspective on the application of the NLR as a valuable tool enabling clinicians to better assess the occurrence and prognosis of complications in patients undergoing dialysis.

The Role of Dyslipidemia in Atherogenesis in Peritoneal Dialysis Patients

Background

To evaluate atherosclerotic changes in carotid arteries (CCA) in uremic patients before and after 18 months of continuous ambulatory peritoneal dialysis (CAPD) treatment, and to evaluate the impact of dyslipidemia and CAPD treatment on vascular remodeling.

Materials and Methods

We conducted a longitudinal, prospective study during 2020 and 2021 at the Clinic for Nephrology, Clinical Center University of Sarajevo. Patients with end-stage renal disease were included and were followed during 18 months of CAPD treatment. All patients were treated using commercially prepared biocompatible balanced dialysis solutions. Carotid intima-media thickness (IMT) and atherosclerotic plaques on the common carotid artery (CCA) were measured by echotomography.

Results

A total of 50 patients were included and were followed during 18 months of CAPD treatment. Lipid values in the serum of patients with CAPD were significantly lower after 18 months of CAPD treatment compared to the values before treatment, while the value of high-density lipoprotein (HDL) was significantly increased after 18 months of CAPD treatment. The values of IMT and the diameter of the CCA compared to the basal values were significantly lower (P < 0.001).

Conclusion

We demonstrated significantly lower lipid values and higher HDL levels following CAPD treatment. Correct selection of the targeted pharmacological intervention can substantially impact the regression of vascular changes in patients on peritoneal dialysis.

Remnant cholesterol as a risk factor for all-cause and cardiovascular mortality in incident peritoneal dialysis patients

BACKGROUND AND AIMS

Remnant cholesterol (RC) adversely contributes to cardiovascular disease (CVD) and overall survival in various diseases. However, its role in CVD outcomes and all-cause mortality in patients undergoing peritoneal dialysis (PD) is limited. Therefore, we aimed to investigate the association between RC and all-cause and CVD mortality in patients undergoing PD.

METHODS AND RESULTS

Based on lipid profiles recorded using standard laboratory procedures, fasting RC levels were calculated in 2710 incident patients undergoing PD who were enrolled between January 2006 and December 2017 and followed up until December 2018. Patients were divided into four groups according to the quartile distribution of baseline RC levels (Q1: <0.40 mmol/L, Q2: 0.40 to <0.64 mmol/L, Q3: 0.64 to <1.03 mmol/L, and Q4: ≥1.03 mmol/L). Associations between RC and CVD and all-cause mortality were evaluated using multivariable Cox models. During the median follow-up period of 35.4 months (interquartile range, 20.9-57.2 months), 820 deaths were recorded, of which 438 were CVD-related. Smoothing plots showed non-linear relationships between RC and adverse outcomes. The risks of all-cause and CVD mortality increased progressively through the quartiles (log-rank, p < 0.001). Using adjusted proportional hazard models, a comparison of the highest (Q4) to lowest (Q1) quartiles revealed significant increases in the hazard ratio (HR) for all-cause mortality (HR 1.95 [95% confidence interval (CI), 1.51-2.51]) and CVD mortality risk (HR 2.60 [95% CI, 1.80-3.75]).

CONCLUSION

An increased RC level was independently associated with all-cause and CVD mortality in patients undergoing PD, suggesting that RC was important clinically and required further research.

Effects of Home-Based Exercise Training on Cardiac Autonomic Neuropathy and Metabolic Profile in Diabetic Hemodialysis Patients

Background: This study aimed to investigate the effects of a home-based exercise training program on Cardiac Autonomic Neuropathy (CAN) and metabolic profile in Diabetic Kidney Disease (DKD) patients undergoing maintenance hemodialysis (HD). Method: Twenty-eight DKD patients undergoing hemodialysis were randomly assigned into two groups. The exercise (EX) group followed a 6-month combined exercise training program at home, while the control (CO) group remained untrained. All participants at baseline and the end of the study underwent cardiopulmonary exercise testing (CPET), biochemical tests for glucose and lipid profile, and 24-h electrocardiographic monitoring for heart rate variability (HRV) analysis and heart rate turbulence (HRT). Results: At the end of the study, compared to the CO, the EX group showed a significant increase in serum high-density lipoprotein (HDL) by 27.7% (p = 0.01), peak oxygen uptake (VO2peak) by 9.3% (p < 0.05), the standard deviation of R-R intervals (SDNN) by 34.3% (p = 0.03), percentage of successive RR intervals higher than 50ms (pNN50) by 51.1% (p = 0.02), turbulence slope (TS) index by 18.4% (p = 0.01), and decrease in (glycated hemoglobin) HbA1c by 12.5% (p = 0.04) and low-frequency power LF (ms2) by 29.7% (p = 0.01). Linear regression analysis after training showed that VO2peak was correlated with SDNN (r = 0.55, p = 0.03) and HF (r = 0.72, p = 0.02). Multiple regression analysis indicated that the improvement of sympathovagal balance and aerobic capacity depended on patients’ participation in exercise training. Conclusion: In conclusion, a 6-month home-based mixed-type exercise program can improve cardiac autonomic function and metabolic profile in DKD patients on HD.

Is the measurement of tissue advanced glycosylation products by skin autofluorescence associated with mortality in patients treated by peritoneal dialysis?

BACKGROUND

Advanced glycosylated end-products (AGEs) have been shown to cause cardiovascular disease, and tissue AGE accumulation can be measured by skin autofluorescence (SAF). AGEs are cleared by the kidney, and thus accumulate in dialysis patients. However, as the results of SAF measurements in peritoneal dialysis patients (PD) have been ambiguous, we examined the association between mortality and SAF.

METHODS

We reviewed SAF measurements in PD patients attending a university associated PD program, along with standard measurements of dialysis adequacy and peritoneal membrane function.

RESULTS

We studied 341 prevalent PD patients, 61.9% male, mean age 61.2 ± 16 years, and 31.4% of all patients died during a median follow-up of 27.2 (23.3-36.3) months. Patients who died were older, mean age 72 ± 10.5 years, were more often diabetic (60.7%), and had higher median SAF 3.8 (3.2-4.5) AU. On logistic regression, mortality was independently associated with age (odds ratio (OR) 1.1 (95% confidence limits 1.06-1.16), diabetes OR 10.1 (3.1-33.4), SAF OR 3.3 (1.8-6.2), all p < 0.001, and male gender OR 5.2 (1.6-17.4), p = 0.007; and negatively associated with weight OR 0.91 (0.86-0.95), p < 0..001, normalised nitrogen appearance rate (nPNA) OR 0.05 (0.01-0.4), p = 0.005 and mean arterial blood pressure (MAP) OR 0.96 (0.93-0.96), p = 0.03.

CONCLUSIONS

In this observational study, SAF was independently associated with mortality. However, other factors were also associated with mortality, including age, diabetes and malnutrition which have all been reported to affect SAF measurements. Thus, the additional predictive value of measuring SAF compared to standard risk factors for mortality remains to be determined.

The effects of mineralocorticoid receptor antagonists on cardiovascular outcomes in patients with end-stage renal disease and heart failure

AIMS

Mineralocorticoid receptor antagonists (MRAs) have been shown to provide survival benefits in patients with heart failure; however, MRA use in patients with chronic kidney disease has been limited by safety concerns. The effects of MRAs on outcomes in patients with end-stage renal disease (ESRD) and heart failure remain unknown. The aim of this study was to evaluate the effects of MRAs on cardiovascular outcomes in patients with heart failure under maintenance dialysis in a real-world setting.

METHODS AND RESULTS

A retrospective cohort study was conducted by collecting data from the Taiwan National Health Insurance Research Database (NHIRD). Patients diagnosed with heart failure and ESRD and who started maintenance dialysis between 1 January 2001 and 31 December 2013 were identified. Patients were grouped according to MRA prescription. The outcomes of interest included cardiovascular (CV) death, hospitalization for heart failure (HHF), all-cause mortality, acute myocardial infarction (AMI), ischaemic stroke, any coronary revascularization procedures, and new-onset hyperkalaemia. Propensity score matching was performed at a 1:3 ratio between MRA users and non-users to minimize selection bias. A total of 50 872 patients who satisfied our inclusion and exclusion criteria were identified. After 1:3 matching, 2176 patients were included in the MRA group, and 6528 patients were included in the non-MRA group. The risk of CV death was significantly lower among patients who received MRAs than those who did not (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.80-0.95), as was the risk of all-cause mortality (HR 0.88, 95% CI 0.83-0.94). Reductions in the risks of CV death and all-cause mortality were more prominent among patients undergoing haemodialysis and those with coronary artery disease.

CONCLUSIONS

In patients undergoing regular dialysis who are diagnosed with heart failure, the use of MRAs is associated with lower risks of all-cause mortality and CV death. The benefits of MRA treatment in heart failure may persist in patients with ESRD. Further investigations through randomized controlled trials are needed to assess the efficacy and safety of MRAs in this high-risk population.

Comparison of soluble suppression of tumorigenicity 2 and brachial hemodynamic parameters between dialysis modalities in patients with end-stage kidney disease

PURPOSE

Major cardiovascular events (MACE) are the leading cause of mortality in patients with chronic kidney disease. Although hemodialysis (HD) and peritoneal dialysis (PD) are comparable in survival, patients with HD have a significantly higher risk of developing MACE. Soluble suppression of tumorigenicity 2 (sST2) is a cardiac biomarker, that does not vary with age, gender, and kidney function. This study aimed to compare arterial stiffness, fluid status, and sST2 levels, between patients with PD and those with in-center HD.

METHODS

This was a cross-sectional study, which was conducted with 36 PD patients, 36 HD patients, and 36 age, and gender-matched healthy controls. We used noninvasive methods for the assessment of arterial stiffness and fluid status.

RESULTS

The patients with PD overhydrated compared to HD patients and healthy control (p < 0.001, and p = 0.05, respectively). Patients with PD had higher central systolic blood pressure and central pulse pressure than patients with HD and the control group (p = 0.004, and p = 0.01; p < 0.001, and p = 0.004, respectively). HD patients had a significantly higher level of plasma sST2 level compared to PD patients and the control group (p = 0.03, and p = 0.005). HD as maintenance dialysis modality and dialysis vintage was associated with higher plasma sST2 concentration, and having a residual renal function in dialysis patients was related to the lower plasma sST2 concentration.

CONCLUSION

PD is associated with better sST2 levels even though higher volume load than HD. In addition, the loss of RRF may be the most important factor related to increased sST2.

Predialysis and Dialysis Therapies Differently Affect Nitric Oxide Synthetic Pathway in Red Blood Cells from Uremic Patients: Focus on Peritoneal Dialysis

Red blood cells (RBCs) have been found to synthesize and release both nitric oxide (NO) and cyclic guanosine monophosphate (cGMP), contributing to systemic NO bioavailability. These RBC functions resulted impaired in chronic kidney disease (CKD). This study aimed to evaluate whether predialysis (conservative therapy, CT) and dialysis (peritoneal dialysis, PD; hemodialysis, HD) therapies used during CKD progression may differently affect NO-synthetic pathway in RBCs. Our data demonstrated that compared to PD, although endothelial-NO-synthase activation was similarly increased, HD and CT were associated to cGMP RBCs accumulation, caused by reduced activity of cGMP membrane transporter (MRP4). In parallel, plasma cGMP levels were increased by both CT and HD and they significantly decreased after hemodialysis, suggesting that this might be caused by reduced cGMP renal clearance. As conceivable, compared to healthy subjects, plasma nitrite levels were significantly reduced by HD and CT but not in patients on PD. Additionally, the increased carotid intima-media thickness (IMT) values did not reach the significance exclusively in patients on PD. Therefore, our results show that PD might better preserve the synthetic NO-pathway in CKD-erythrocytes. Whether this translates into a reduced development of uremic vascular complications requires further investigation.