Associations between central pulse pressure, microvascular endothelial function, and fluid overload in peritoneal dialysis patients.

BACKGROUND: Microcirculatory endothelial dysfunction is a complex phenomenon that contributes to the development of cardiovascular disease. However, the relationship between microcirculatory endothelial dysfunction and macrovascular disease remains incompletely understood. Fluid overload is a risk factor for cardiovascular mortality in patients undergoing peritoneal dialysis. Therefore, we investigated the effects of chronic fluid overload on both the microcirculation and macrocirculation in these patients. METHODS: Thirty patients undergoing peritoneal dialysis were included in this cross-sectional study. We measured their central blood pressure and pulse wave velocity, assessed their microvascular endothelial function using drug-induced iontophoresis with laser Doppler flowmetry, and determined the amount of fluid overload using bioimpedance. We conducted a Spearman correlation analysis, univariate analysis, and stepwise multivariate regression models to determine the associations among the hemodynamic parameters. RESULTS: Acetylcholine-induced iontophoresis with laser Doppler flowmetry showed a correlation with both brachial and central pulse pressure (PP), but not with pulse wave velocity. Fluid overload was associated with both central and brachial PP and remained an independent predictor of central PP even after adjusting for multiple factors. However, fluid overload was not associated with microcirculatory endothelial function. CONCLUSION: In peritoneal dialysis patients, we observed a significant association between central PP and microvascular endothelial function, indicating a connection between macrocirculation and microcirculation. However, conclusive evidence regarding fluid overload as a mediator between these circulatory systems is lacking. Further research is needed to investigate this relationship.

Early fluid management affects short-term mortality in patients with end-stage kidney disease undergoing chronic hemodialysis and requiring continuous renal replacement therapy.

BACKGROUND: Early fluid management is considered a key element affecting mortality in critically ill patients requiring continuous renal replacement therapy (CRRT). Most studies have primarily focused on patients with intrinsic acute kidney injury requiring CRRT, although end-stage kidney disease (ESKD) patients generally exhibit greater vulnerability. We investigated the association between fluid balance and short-term mortality outcomes in ESKD patients undergoing chronic hemodialysis and requiring CRRT. METHODS: This retrospective study included 110 chronic hemodialysis patients who received CRRT between 2017 and 2019 at Ewha Womans University Mokdong Hospital. The amounts of daily input and output, and cumulative 3-day and 7-day input and output, were assessed from the initiation of CRRT. The participants were classified into two groups based on 7-day and 14-day mortalities. Cox regression analyses were carried out on the basis of the amounts of daily input and output, cumulative input and output, and cumulative fluid balance. RESULTS: During follow-up, 7-day and 14-day mortalities were observed in 24 (21.8%) and 34 (30.9%) patients. The patients were stratified into two groups (14-day survivors vs. non-survivors), and there were no significant differences in demographic characteristics between the two groups. However, diabetes mellitus was more common among survivors than among non-survivors. Univariate analyses showed that the amounts of daily output at 48, and 72 h, and 3-day cumulative input and output, were significantly associated with 7-day mortality risk regardless of the cumulative fluid balance (HR: 0.28, 95% CI: 0.12-0.70, p = 0.01 for daily output at 48 h; HR: 0.34, 95% CI: 0.13-0.85, p = 0.02 for daily output at 72 h.; HR: 0.72, 95% CI: 0.61-0.86, p = 0.01 for 3-day cumulative input; HR: 0.65, 95% CI: 0.41-0.90, p = 0.01 for 3-day cumulative output). Adjusted multivariate analyses showed that the lower 3-day cumulative output is an independent risk factor for 7-day and 14-day mortality. CONCLUSIONS: In our study, increased cumulative output were significantly associated with reduced short-term mortality risk in chronic hemodialysis patients undergoing CRRT regardless of cumulative fluid balance. Further prospective studies to investigate the association between fluid balance and mortality in ESRD patients requiring CRRT are warranted.

Uric acid induced the phenotype transition of vascular endothelial cells via induction of oxidative stress and glycocalyx shedding.

Recent data suggested a causative role of uric acid (UA) in the development of renal disease, in which endothelial dysfunction is regarded as the key mechanism. Endothelial-to-mesenchymal transition (EndoMT) and shedding of the glycocalyx are early changes of endothelial dysfunction. We investigated whether UA induced EndoMT in HUVECs and an animal model of hyperuricemia fed with 2% oxonic acid for 4 wk. UA induced EndoMT in HUVECs with a generation of reactive oxygen species via the activation of membranous NADPH oxidase (from 15 min) and mitochondria (from 6 h) along with glycocalyx shedding (from 6 h), which were blocked by probenecid. GM6001, an inhibitor of matrix metalloproteinase, alleviated UA-induced glycocalyx shedding and EndoMT. Antioxidants including N-acetyl cysteine, apocynin, and mitotempo ameliorated EndoMT; however, they did not change glycocalyx shedding in HUVECs. In the kidney of hyperuricemic rats, endothelial staining in peritubular capillaries (PTCs) was substantially decreased with a de novo expression of α-smooth muscle actin in PTCs. Plasma level of syndecan-1 was increased in hyperuricemic rats, which was ameliorated by allopurinol. UA caused a phenotypic transition of endothelial cells via induction of oxidative stress with glycocalyx shedding, which could be one of the mechanisms of UA-induced endothelial dysfunction and kidney disease.-Ko, J., Kang, H.-J., Kim, D.-A., Kim, M.-J., Ryu, E.-S., Lee, S., Ryu, J.-H., Roncal, C., Johnson, R. J., Kang, D.-H. Uric acid induced the phenotype transition of vascular endothelial cells via induction of oxidative stress and glycocalyx shedding.

The effect of uric acid and urinary sodium excretion on prehypertension: a nationwide population-based study.

BACKGROUND: This study examined the effect of serum uric acid (SUA) level and urinary sodium excretion on blood pressure as well as their combined effect on prehypertension in a Korean population. METHOD: Data from the 7th Korea National Health and Nutrition Examination Survey for adults (≥ 19 years of age) were used. The participants were classified into two groups, normotension and prehypertension, according to the JNC-7 definition. Logistic regression was carried out and adjusted for traditionally regarded confounders of blood pressure. All analyses considered a complex sampling design. A multivariate analysis was performed on subgroups defined according to their SUA level and urinary sodium excretion. RESULTS: The 4200 participants were divided into normotension (n = 2646) and prehypertension (n = 1554) groups. In the univariate analysis, patient age, male sex, concurrent comorbidity (diabetes mellitus, cardiovascular disease, stroke, dyslipidemia, and chronic kidney disease), uric acid, and urinary sodium excretion were associated with prehypertension. After adjusting for baseline covariates, both the SUA level and urinary sodium excretion were significant predictors of incident prehypertension (SUA, per 1 mg/dL increase, odds ratio [OR] 1.216, 95% confidence interval [95% CI] 1.131-1.309; urinary sodium excretion, per 1 g/day increase, OR 1.067, 95% CI 1.019-1.117). Additionally, simultaneously higher tertiles of SUA and urinary sodium excretion resulted in higher ORs for prehypertension. CONCLUSION: Increased SUA is a significant risk marker for the development of prehypertension in normotensives. Simultaneously high SUA and urinary sodium excretion amplified the effect on the development of prehypertension. Our findings suggest that lowering SUA levels and reducing sodium intake will contribute to preventing hypertension.

The interactive effects of input and output on managing fluid balance in patients with acute kidney injury requiring continuous renal replacement therapy.

BACKGROUND: The interactive effect of cumulative input and output on achieving optimal fluid balance has not been well elucidated in patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). This study evaluated the interrelation of fluid components with mortality in patients with AKI requiring CRRT. METHODS: This is a retrospective observational study conducted with a total of 258 patients who were treated with CRRT due to AKI between 2016 and 2018 in the intensive care unit of Ewha Womans University Mokdong Hospital. The amounts of fluid input and output were assessed at 24-h and 72-h from the initiation of CRRT. The study endpoints were 7- and 28-day all-cause mortality. RESULTS: The mean patient age was 64.7 ± 15.8 years, and 165 (64.0%) patients were male. During the follow-up, 7- and 28-day mortalities were observed in 120 (46.5%) and 157 (60.9%) cases. The patients were stratified into two groups (28-day survivors vs. non-survivors), and the cumulative fluid balances (CFBs) at 24 h and 72 h were significantly higher in the 28-day non-survivors compared with the survivors. The increase in 24-h and 72-h CFB was significantly associated with an increase in 7- and 28-day mortality risks. To examine the interactive effect of cumulative input or output on the impact of CFB on mortality, we also stratified patients into three groups based on the tertile of 24-h and 72-h cumulative input or output. The increases in 24-h and 72-h CFBs were still significantly related to the increases in 7-day and 28-day mortality, irrespective of the cumulative input. However, we did not find significant associations between increase in 24-h and 72-h CFB and increase in mortality risk in the groups according to cumulative output tertile. CONCLUSIONS: The impact of cumulative fluid balance on mortality might be more dependent on cumulative output. The physicians need to decrease the cumulative fluid balance of CRRT patients as much as possible and consider increasing patient removal.

Dementia is a risk factor for major adverse cardiac and cerebrovascular events in elderly Korean patients initiating hemodialysis: a Korean national population-based study.

BACKGROUND: Dementia is common in end-stage renal disease (ESRD) patients on hemodialysis (HD) and is associated with worse outcomes. This study aimed to investigate the risk of major adverse cardiac and cerebrovascular event (MACCE) in elderly patients with dementia initiating HD. METHODS: Using the database from the Health Insurance Review & Assessment Service, we analyzed 10,171 patients aged 65 years or older who had initiated dialysis from 2005 to 2008. MACCE was defined as a composite outcome of all-cause mortality, nonfatal acute myocardial infarction, target vessel revascularization, and nonfatal ischemic and hemorrhagic stroke. The Kaplan-Meier method and Cox proportional hazards model were used, and further comparisons using propensity-score matching at 1:2 ratio were also performed. RESULTS: A total of 303 elderly patients (3.0%) had dementia at initiating HD. During follow-up, dementia was a significant predictor of MACCE after adjustment for confounding variables. In addition, further analyzed in the propensity-score matched groups, dementia was an independent predictor of both nonfatal ischemic stroke and all-cause mortality. CONCLUSIONS: Dementia is an independent risk factor for mortality and ischemic stroke in elderly ESRD patients initiating HD. Patients with dementia who start dialysis should be closely monitored to reduce the risk of mortality and ischemic stroke.

Comparison of epitheliotrophic factors in autologous serum eyedrops from sera of chronic renal failure patients vs. normal controls.

PURPOSE: To investigate the composition and biological activity of serum epitheliotrophic factors from chronic renal failure (CRF) patients vs. healthy controls. METHODS: Twenty, 50 and 100 % autologous serum eyedrops (ASEs) were prepared from 16 CRF patients and 16 normal subjects. Serum epithelial growth factor (EGF), platelet-derived growth factor-AB (PDGF-AB), transforming growth factor-ß1 (TGF-ß1) and fibronectin levels were quantified using enzyme-linked immunosorbent assay kits. A 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliumbromide (MTT) assay was used to compare the proliferative effects of serum from CRF patients and healthy donors in a human corneal epithelial cell (HCEC) culture model. Migration assays were conducted via manual scraping of HCECs for migratory potential of ASEs. Morphologic changes were studied with transmission electron microscopy (TEM). RESULTS: EGF, PDGF-AB and TGF-ß1 levels in ASEs from healthy donors were significantly higher than in serum of CRF patients. Cellular proliferation was similar in the CRF patient and normal control groups. ASEs from the normal group had a significantly higher effect on cell migration. ASEs in both groups facilitated better proliferation and migration than the negative control. Furthermore, we observed an enhancement after incubation with diluted serum vs. undiluted serum. In TEM analysis, HCECs incubated with CRF patients' 50 % ASEs showed some loss of microvilli without alterations of cytoplasmic organelles. CONCLUSIONS: Epitheliotrophic factors concentrations and biologic activities from CRF patient sera differed from healthy controls. ASEs in CRF patients are also helpful in the corneal healing process, especially when applied at a 50 % concentration.

A population-based approach indicates an overall higher patient mortality with peritoneal dialysis compared to hemodialysis in Korea.

To date, only a few large-scale studies have measured the effect of dialysis modality on mortality in Asian populations. Here, we sought to compare survival between incident hemodialysis (HD) and peritoneal dialysis (PD) patients using the Korean Health Insurance Review & Assessment Service database. This enabled us to perform a population-based complete survey that included 32,280 incident dialysis patients and followed them for a median of 26.5 months. To reduce biases due to nonrandomization, we first matched 7049 patient pairs with similar propensity scores. Using the log-rank test, we found the mortality rate in PD patients was significantly higher than that in HD patients. Subsequent subgroup analyses indicated that in older patients (55 years and older), with the exception of the subgroup of patients with no comorbidities and the subgroup of patients with malignancy, PD was consistently associated with a higher mortality rate. In younger patients (under 55 years), regardless of the covariates, the survival rate of PD patients was comparable to that of HD patients. Thus, while the overall mortality rate was higher in incident PD patients, mortality rates of some incident PD and HD patients were comparable in Korea.

Progressive increase in vascular access blood flow after percutaneous transluminal angioplasty in patients on hemodialysis.

Percutaneous transluminal angioplasty (PTA) is the gold standard for treating stenoses with dysfunctional vascular access. Recently, we found that vascular access blood flow (VABF) measured immediately after PTA increased over time without the need for additional procedures in the patients who underwent PTA. Therefore, this study was conducted to confirm an increase in VABF after PTA and identify the factors associated with it. Patients on chronic hemodialysis at a single institution were retrospectively reviewed and those with accesses that had a measurement of VABF immediately after PTA and within 1 month from PTA were included in the study. The relationship between clinical parameters and changes in VABF were analyzed using paired t-test and linear regression. A total of 47 PTA accesses (fistulas, 26; grafts,21) were included. The mean VABF on the day of PTA and the following measurement were 796.9 ±â€…329.1 mL/min and 1105.1 ±â€…410.3 mL/min, respectively. In the univariate analysis, the diameter of the balloon catheter used in the PTA and serum uric acid (SUA) level were significantly associated with an increase in VABF. Atrial fibrillation was a significant factor for the percentage change in vascular access. In the multivariate analysis, SUA level, balloon catheter diameter, and atrial fibrillation remained independent factors for changes in VABF and percentage change in VABF, respectively. The study identified progressive increases in the VABF after PTA without additional procedures. SUA level, balloon catheter diameter used in PTA, and atrial fibrillation were independently associated with changes in VABF.

Effects of Normal Reference Range of Phosphorus and Corresponding PTH on Endothelial Function in CKD Patients.

Introduction: Endothelial dysfunction commonly occurs in chronic kidney disease (CKD) patients and increases the risk for cardiovascular disease. Among CKD patients, biomarkers involved in the pathogenesis of CKD-mineral bone disorder (CKD-MBD), such as phosphorus, parathyroid hormone, and fibroblast growth factor 23, are associated with endothelial dysfunction. We investigated whether these biomarkers induce endothelial dysfunction in CKD patients with normal phosphorus levels. Methods: This cross-sectional study examined CKD patients with normal phosphorus levels; patients with an estimated glomerular filtration rate (eGFR) <15 or who were under dialysis were excluded. Iontophoresis with laser doppler flowmetry (ILDF) and peripheral arterial tonometry were performed to assess endothelial function in 85 patients. Pearson's correlation coefficient, multiple regression, and mediation analyses were performed to examine the association between CKD-MBD biomarkers and endothelial dysfunction. Results: Endothelial dysfunction was observed in all subjects with a low response to ILDF and 27% of subjects according to peripheral arterial tonometry. Acetylcholine (Ach)-induced ILDF was significantly associated with eGFR (r = 0.22, P = 0.04), intact parathyroid hormone (iPTH; r = -0.46, P < 0.01), and VCAM-1 (r = -0.36, P < 0.01). The reactive hyperemia index (RHI) was significantly related to phosphorus levels (r = 0.32, P < 0.01) and iPTH (r = -0.39, P = 0.02). After adjusting for eGFR, iPTH and VCAM-1 remained independent factors for predicting endothelial dysfunction measured using Ach-induced ILDF. In addition, iPTH and phosphorus levels were independent predictors for endothelial dysfunction measured using RHI in the eGFR-adjusted model. Mediation analyses showed that the individual indirect effects of iPTH were significantly affected ILDF and RHI. Conclusion: Serum levels of phosphorus and iPTH are associated with endothelial dysfunction, even in CKD patients with normal phosphorus levels.

Feasibility of Deep Learning-Based Analysis of Auscultation for Screening Significant Stenosis of Native Arteriovenous Fistula for Hemodialysis Requiring Angioplasty.

OBJECTIVE: To investigate the feasibility of using a deep learning-based analysis of auscultation data to predict significant stenosis of arteriovenous fistulas (AVF) in patients undergoing hemodialysis requiring percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: Forty patients (24 male and 16 female; median age, 62.5 years) with dysfunctional native AVF were prospectively recruited. Digital sounds from the AVF shunt were recorded using a wireless electronic stethoscope before (pre-PTA) and after PTA (post-PTA), and the audio files were subsequently converted to mel spectrograms, which were used to construct various deep convolutional neural network (DCNN) models (DenseNet201, EfficientNetB5, and ResNet50). The performance of these models for diagnosing ≥ 50% AVF stenosis was assessed and compared. The ground truth for the presence of ≥ 50% AVF stenosis was obtained using digital subtraction angiography. Gradient-weighted class activation mapping (Grad-CAM) was used to produce visual explanations for DCNN model decisions. RESULTS: Eighty audio files were obtained from the 40 recruited patients and pooled for the study. Mel spectrograms of "pre-PTA" shunt sounds showed patterns corresponding to abnormal high-pitched bruits with systolic accentuation observed in patients with stenotic AVF. The ResNet50 and EfficientNetB5 models yielded an area under the receiver operating characteristic curve of 0.99 and 0.98, respectively, at optimized epochs for predicting ≥ 50% AVF stenosis. However, Grad-CAM heatmaps revealed that only ResNet50 highlighted areas relevant to AVF stenosis in the mel spectrogram. CONCLUSION: Mel spectrogram-based DCNN models, particularly ResNet50, successfully predicted the presence of significant AVF stenosis requiring PTA in this feasibility study and may potentially be used in AVF surveillance.

Treatment and clinical outcomes of elderly idiopathic membranous nephropathy: A multicenter cohort study in Korea.

Idiopathic membranous nephropathy (MN) is the most common glomerulonephritis in elderly patients showing nephrotic syndrome. However, little is known about its treatment options and outcomes in elderly MN patients at long term follow-up. We retrospectively enrolled patients with biopsy-proven MN between April 1990 and December 2015 from eight tertiary hospitals in Korea. Among them, we excluded patients who had secondary causes of MN and subnephrotic-range proteinuria. We evaluated the presenting features and clinical outcomes and analyzed the all-cause mortality, renal outcomes, infection, and remission with respect to age. During the median follow-up at 77.2 months, 198 younger patients (<65 years) and 133 elderly patients (≥65 years) were enrolled. Age was an independent risk factor for all-cause mortality, renal outcome, and infection (for all P < 0.05) except remission. In elderly patients, there was no significant factor associated with mortality rate. The use of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) was significantly associated with renal outcome and infection (renal outcome, hazard ration [HR] 0.06, 95% confidence intervals [CI] 0.01-0.36, P = 0.003; infection, HR 0.20, 95% CI 0.04-0.94, P = 0.041). Immunosuppressant therapy significantly increased renal outcome (P = 0.045) and infection (P = 0.029) compared with conservative therapy. In conclusion, old age is one of the clinically important predictors for MN patients. Among the treatment of elderly MN patients, only ACEI or ARB was associated with beneficial effects on renal outcome and infection. Elderly MN patients need a more tailored regimen considering their comorbidities and condition.

Selective tubular activation of hypoxia-inducible factor-2α has dual effects on renal fibrosis.

Hypoxia-inducible factor (HIF) is a key transcriptional factor in the response to hypoxia. Although the effect of HIF activation in chronic kidney disease (CKD) has been widely evaluated, the results have been inconsistent until now. This study aimed to investigate the effects of HIF-2α activation on renal fibrosis according to the activation timing in inducible tubule-specific transgenic mice with non-diabetic CKD. HIF-2α activation in renal tubular cells upregulated mRNA and protein expressions of fibronectin and type 1 collagen associated with the activation of p38 mitogen-activated protein kinase. In CKD mice, activation of HIF-2α at the beginning of CKD significantly aggravated renal fibrosis, whereas it did not lead to renal dysfunction. However, activation at a late-stage of CKD abrogated both renal dysfunction and fibrosis, which was associated with restoration of renal vasculature and amelioration of hypoxia through increased renal tubular expression of VEGF and its isoforms. As with tubular cells with HIF-2α activation, those under hypoxia also upregulated VEGF, fibronectin, and type 1 collagen expressions associated with HIF-1α activation. In conclusion, late-stage renal tubular HIF-2α activation has protective effects on renal fibrosis and the resultant renal dysfunction, thus it could represent a therapeutic target in late stage of CKD.

The Relationship between Magnesium and Endothelial Function in End-Stage Renal Disease Patients on Hemodialysis.

PURPOSE: Chronic kidney disease (CKD) patients tend to have higher serum magnesium values than healthy population due to their positive balance of magnesium in kidney. Recent studies found that magnesium level is positively correlated with endothelial function. Therefore, this study was conducted to define the relationship between magnesium level and endothelial dysfunction in end stage renal disease (ESRD) patients on hemodialysis (HD). MATERIALS AND METHODS: A total of 27 patients were included in this cross-sectional study. Iontophoresis with laser-Doppler flowmetry, flow mediated dilation (FMD), and carotid intima-media thickness were measured. Patients' average serum magnesium levels were measured over previous three months, including the examination month. Pearson's correlation coefficient analysis and multivariate regression model were used to define the association between magnesium and endothelial function. RESULTS: In the univariate analysis, higher magnesium levels were associated with better endothelium-dependent vasodilation (EDV) of the FMD in ESRD patients on HD (r=0.516, p=0.007). When the participants were divided into two groups according to the median magnesium level (3.47 mg/dL), there was a significant difference in EDV of FMD (less than 3.47 mg/dL, 2.8±1.7%; more than 3.47 mg/dL, 5.1±2.0%, p=0.004). In multivariate analysis, magnesium and albumin were identified as independent factors for FMD (ß=1.794, p=0.030 for serum magnesium; ß=3.642, p=0.012 for albumin). CONCLUSION: This study demonstrated that higher serum magnesium level may be associated with better endothelial function in ESRD patients on HD. In the future, a large, prospective study is needed to elucidate optimal range of serum magnesium levels in ESRD on HD patients.

Technique failure in Korean incident peritoneal dialysis patients: a national population-based study.

BACKGROUND: Technique failure is an important issue for peritoneal dialysis (PD) patients. In this study, we aimed to analyze technique failure rate in detail and to determine the predictors for technique failure in Korea. METHODS: We identified all patients who had started dialysis between January 1, 2005, and December 31, 2008, in Korea, using the Korean Health Insurance Review and Assessment Service database. A total of 7,614 PD patients were included, and the median follow-up was 24.9 months. RESULTS: The crude incidence rates of technique failure in PD patients were 54.1 per 1,000 patient-years. The cumulative 1-, 2-, and 3-year technique failure rates of PD patients were 4.9%, 10.3%, and 15.6%, respectively. However, those technique failure rates by Kaplan-Meier analysis were overestimated compared with the values by competing risks analysis, and the differences increased with the follow-up period. In multivariate analyses, diabetes mellitus and Medical Aid as a crude reflection of low socioeconomic status were independent risk factors in both the Cox proportional hazard model and Fine and Gray subdistribution model. In addition, cancer was independently associated with a lower risk of technique failure in the Fine and Gray model. CONCLUSION: Technique failure was a major concern in patients initiating PD in Korea, especially in diabetic patients and Medical Aid beneficiaries. The results of our study offer a basis for risk stratification for technique failure.

Improving survival rate of Korean patients initiating dialysis.

PURPOSE: The aim of this study was to investigate whether the survival rate among Korean dialysis patients changed during the period between 2005 and 2008 in Korea. MATERIALS AND METHODS: A total of 32357 patients who began dialysis between January 1, 2005 and December 31, 2008 were eligible for analysis. Baseline demographics, comorbidities, and mortality data were obtained from the database of the Health Insurance Review & Assessment Service. RESULTS: Kaplan-Meier curves according to the year of dialysis initiation showed that the survival rate was significantly different (log-rank test, p=0.005), most notably among peritoneal dialysis (PD) patients (p<0.001), although not among hemodialysis (HD) patients (p=0.497). In multivariate analysis, however, patients initiating either HD or PD in 2008 also had a significantly lower risk of mortality compared to those who began dialysis in 2005. Subgroup survival analysis among patients initiating dialysis in 2008 revealed that the survival rate of PD patients was significantly higher than that of HD patients (p=0.001), and the survival benefit of PD over HD remained in non-diabetic patients aged less than 65 years after adjustment of covariates. CONCLUSION: Survival of Korean patients initiating dialysis from 2005 to 2008 has improved over time, particularly in PD patients. In addition, survival rates among patients initiating dialysis in 2008 were different according to patients' age and diabetes, thus we need to consider these factors when dialysis modality should be chosen.

Risk of major cardiovascular events among incident dialysis patients: A Korean national population-based study.

BACKGROUND: Dialysis patients are at high risk for cardiovascular diseases, but until now there have been no detailed analyses of the incidences among Asian patients initiating dialysis. The aims of this study were to determine the incidence rates of major adverse cardiac and cerebrovascular events (MACCE) and to compare them between incident HD patients and PD patients. METHODS: We included all patients who had started dialysis between January 1, 2005 and December 31, 2008 in Korea, and analyzed 30,279 eligible patients [22,892 hemodialysis (HD) patients and 7387 peritoneal dialysis (PD) patients] by intention-to-treat. Median follow-up was 21.5 months. RESULTS: The crude incidence rates were as follows: MACCE, 182 per 1000 patient-years (PY); major adverse cardiac events (MACE), 138/1000 PY; all-cause mortality, 116/1000 PY; non-fatal acute myocardial infarction (AMI), 18/1000 PY; target vessel revascularization (TVR), 17/1000 PY; and non-fatal stroke, 60/1000 PY. When comparing all baseline covariate-adjusted relative risks between HD and PD patients, HD is overall superior to PD in terms of MACCE. Further examined by each endpoint, all-cause mortality, non-fatal AMI, and TVR occurred significantly more frequently in patients on PD than in those on HD, whereas non-fatal hemorrhagic stroke occurred significantly more frequently in patients on HD than in those on PD. CONCLUSIONS: The incidence of MACCE may be different from Western dialysis patients. HD is overall superior to PD in terms of MACCE as an initial dialysis modality. Underlying mechanisms differentially affecting cardiovascular outcomes by dialysis modality remain to be further elucidated.

An assessment of survival among Korean elderly patients initiating dialysis: a national population-based study.

BACKGROUND: Although the proportion of the elderly patients with incident end-stage renal disease (ESRD) patients has been increasing in Korea, there has been a lack of information on outcomes of dialysis treatment. This study aimed to assess the survival rate and to elucidate predictors for all-cause mortality among elderly Korean patients initiating dialysis. METHODS: We analyzed 11,301 patients (6,138 men) aged 65 years or older who had initiated dialysis from 2005 to 2008 and had followed up (median, 37.8 months; range, 3-84 months). Baseline demographics, comorbidities and mortality data were obtained using the database from the Health Insurance Review & Assessment Service. RESULTS: The unadjusted 5-year survival rate was 37.6% for all elderly dialysis patients, and the rate decreased with increasing age categories; 45.9% (65∼69), 37.5% (70∼74), 28.4% (75∼79), 24.1% (80∼84), and 13.7% (≥85 years). The multivariate Cox proportional hazard model revealed that age, sex, dialysis modality, the type of insurance, and comorbidities such as diabetes mellitus, myocardial infarction, congestive heart failure, peripheral vascular disease, cerebrovascular disease, dementia, chronic pulmonary disease, hemiparesis, liver disease, and any malignancy were independent predictors for mortality. In addition, survival rate was significantly higher in patients on hemodialysis compared to patients on peritoneal dialysis during the whole follow-up period in the intention-to-treat analysis. CONCLUSIONS: Survival rate was significantly associated with age, sex, and various comorbidities in Korean elderly patients initiating dialysis. The results of our study can help to provide relevant guidance on the individualization strategy in elderly ESRD patients requiring dialysis.