End-stage renal disease, atherosclerosis, and cardiovascular mortality: is C-reactive protein the missing link?

Effectiveness of fish oil in controlling inflammation in adult patients undergoing hemodialysis: A systematic review and meta-analysis

Objective

Hemodialysis patients with chronic kidney disease often exhibit inflammation characterized by elevated levels of C-reactive protein, Interleukin 6 and tumor necrosis factor-alpha, and they are shown to be associated with cardiovascular impairment and enhanced renal failure. This study aims to assess the impact of fish oil intake on inflammation indicators in adult hemodialysis patients.

Methods

From the inception to December 2023, the datasets Cochrane Central, Google Scholar, Science Direct, Embase, and Pubmed were examined. Two authors independently searched, selected, and screened the literature. The pooled results are represented by weighted mean difference (WMD) with 95% confidence intervals. To investigate the causes of heterogeneity, subgroup analysis was done. Sensitivity analysis was then used to evaluate the validity of the combined findings.

Results

Thirteen randomized control trials studies were included. The pooled results showed that fish oil supplementation caused a significant reduction of the C-reactive protein level (WMD, -2.92 mg/L; 95% Confidence interval, -5.23, to -0.61; p = 0.01; I 2 = 99%), especially in patients with baseline C-reactive protein ⩾5 mg/L (WMD, -4.39 mg/L; 95% Confidence interval, -5.93 to 2.85; p < 0.00001; I 2 = 33%). Subgroup analyses showed that C-reactive protein baseline level (C-reactive protein <5 mg/L) was the main source of heterogeneity. Fish oil intake may not reduce the level of Interleukin 6 (WMD, -2.26; 95% Confidence interval: -19.61 to 15.09; p = 0.80; I 2 = 93%), nor will it reduce the level of tumor necrosis factor-alpha (random model: WMD, -2.51; 95% Confidence interval: 6.08 to 1.06; p = 0.17; I 2 = 98%).

Conclusion

Hemodialysis patients, especially those with C-reactive protein > 5 mg/L, responded to fish oil supplementation to reduce their C-reactive protein level; however, Interleukin 6 and tumor necrosis factor-alpha levels did not appear to be affected.

Immunosenescence, gut dysbiosis, and chronic kidney disease: Interplay and implications for clinical management

Immunosenescence refers to the immune system changes observed in individuals over 50 years old, characterized by diminished immune response and chronic inflammation. Recent investigations have highlighted similar immune alterations in patients with reduced kidney function. The immune system and kidney function have been found to be closely interconnected. Studies have shown that as kidney function declines, both innate and adaptive immunity are affected. Chronic kidney disease (CKD) patients exhibit decreased levels of naive and regular T cells, as well as naive and memory B cells, while memory T cell counts increase. Furthermore, research suggests that CKD and end-stage kidney disease (ESKD) patients experience early thymic dysfunction and heightened homeostatic proliferation of naive T cells. In addition to reduced thymic T cell production, CKD patients display shorter telomeres in both CD4+ and CD8+ T cells. Declining kidney function induces uremic conditions, which alter the intestinal metabolic environment and promote pathogen overgrowth while reducing diversity. This dysbiosis-driven imbalance in the gut microbiota can result in elevated production of uremic toxins, which, in turn, enter the systemic circulation due to compromised gut barrier function under uremic conditions. The accumulation of gut-derived uremic toxins exacerbates local and systemic kidney inflammation. Immune-mediated kidney damage occurs due to the activation of immune cells in the intestine as a consequence of dysbiosis, leading to the production of cytokines and soluble urokinase-type plasminogen activator receptor (suPAR), thereby contributing to kidney inflammation. In this review, we delve into the fundamental mechanisms of immunosenescence in CKD, encompassing alterations in adaptive immunity, gut dysbiosis, and an overview of the clinical findings pertaining to immunosenescence.

Long-term outcomes of lung transplantation requiring renal replacement therapy: A single-center experience

BACKGROUND

Life-long immunosuppressive therapy after lung transplantation (LT) may lead to end-stage renal disease (ESRD), requiring renal replacement therapy (RRT). We aimed to investigate the characteristics and long-term outcomes of patients undergoing LT and requiring RRT.

METHODS

This study was a single-center, retrospective cohort study. The patients were divided into the RRT (n = 15) and non-RRT (n = 170) groups. We summarized the clinical features of patients in the RRT group and compared patient characteristics, overall survival, and chronic lung allograft dysfunction (CLAD)-free survival between the two groups.

RESULTS

The cumulative incidences of ESRD requiring RRT after LT at 5, 10, and 15 years were 0.8 %, 7.6 %, and 25.2 %, respectively. In the RRT group, all 15 patients underwent hemodialysis but not peritoneal dialysis, and two patients underwent living-donor kidney transplantation. The median follow-up period was longer in the RRT group than in the non-RRT group (P < 0.001). The CLAD-free survival and overall survival did not differ between the two groups. The 5-year survival rate even after the initiation of hemodialysis was 53.3 %, and the leading cause of death in the RRT group was infection.

CONCLUSIONS

Favorable long-term outcomes can be achieved by RRT for ESRD after LT.

The effect of oral supplementation of Paricalcitol on C-reactive protein levels in chronic kidney disease patients: GRADE-assessed systematic review and dose-response meta-analysis of data from randomized controlled trials

BACKGROUND

Previous studies investigating the effect of oral supplementation of paricalcitol on reactive protein levels in chronic kidney disease (CKD) patients reported inconsistent findings. In this systematic review and meta-analysis, we have analyzed and interpreted the results obtained from previous randomized clinical trials on the effect of paricalcitol on C-reactive protein in CKD patients in the literature.

METHODS

MEDLINE, SciVerse Scopus, and Clarivate Analytics Web of Science databases were searched until January 2023 and related articles were obtained through a careful screening process allowing extraction of required data from selected articles. The effect size was calculated using a random effect model and weighted mean differences (WMD) and 95% confidence intervals (CI). Heterogeneity among studies was evaluated using Cochran's Q test and I2.

RESULTS

Amongst the 182 articles obtained from the initial search, 4 studies (6 arms) were finally included in the meta-analysis. Pooled analysis shows that C-reactive protein levels significantly decrease after oral supplementation with paricalcitol (WMD: -2.55 mg/L, 95% CI (-4.99 to -0.11; P = 0.04). The studies used in this meta-analysis showed significant heterogeneity (I2 = 66.3% and P = 0.01).

CONCLUSION

Oral paricalcitol supplementation in CKD patients can significantly reduce C-reactive protein levels, which may prevent CKD progression.

Omega-3 Fatty Acids Reduce Remnant-like Lipoprotein Cholesterol and Improve the Ankle-Brachial Index of Hemodialysis Patients with Dyslipidemia: A Pilot Study

Background and Objectives: Omega-3 fatty acids have potent lipid-lowering and antiplatelet effects; however, randomized controlled trials have yet to examine the effect of high-dose omega-3 fatty acid administration on peripheral artery disease (PAD) in hemodialysis patients with dyslipidemia. Therefore, this study aimed to evaluate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the ankle-brachial index (ABI) and remnant-like lipoprotein cholesterol (RLP-C) levels, which are indicators of PAD severity. Materials and Methods: Thirty-eight participants (mean age: 73.6 ± 12.7 years) were randomly assigned using stratified block randomization to either conventional therapy alone or conventional therapy supplemented with high-dose EPA/DHA (EPA: 1860 mg; DHA: 1500 mg) for a three-month intervention period. Patients in the conventional therapy alone group who opted to continue were provided with a low-dose EPA/DHA regimen (EPA: 930 mg; DHA: 750 mg) for an additional three months. The baseline and 3-month values for RLP-C, an atherogenic lipid parameter, and the ABI were recorded. Results: The results of the 3-month assessments revealed that the mean RLP-C changes were -3.25 ± 3.15 mg/dL and 0.44 ± 2.53 mg/dL in the EPA/DHA and control groups, respectively (p < 0.001), whereas the changes in the mean ABI values were 0.07 ± 0.11 and -0.02 ± 0.09 in the EPA/DHA and control groups, respectively (p = 0.007). In the EPA/DHA group, a significant negative correlation was found between the changes in RLP-C levels and the ABI (r = -0.475, p = 0.04). Additionally, the change in the RLP-C levels independently influenced the change in the ABI in the EPA/DHA group, even after adjusting for age, sex, and statin use (p = 0.042). Conclusions: Add-on EPA/DHA treatment improved the effectiveness of conventional therapy (such as statin treatment) for improving the ABI in hemodialysis patients with dyslipidemia by lowering RLP-C levels. Therefore, clinicians involved in dialysis should focus on RLP-C when considering residual cardiovascular disease risk in hemodialysis patients and should consider screening patients with elevated levels.

The Effect of Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism on the Severity and Death Rate of COVID-19 in Iranian Patients

The study was designed to assess the association of ACE I/D polymorphism with the severity and prognosis of COVID-19 in the Iranian population. Hence, 186 adult patients were categorized into three clinical groups based on the severity of COVID-19: 1) Outpatients or mildly symptomatic patients as control (n = 71); 2) Hospitalized patients or severe symptomatic cases (n = 53); 3) Inpatients led to ICU/death or critically ill patients needed mechanical ventilation (n = 62). The possible association of ACE I/D polymorphism with the risk of comorbidities and serum level of C-reactive protein was evaluated in two severe cases. The results showed that the frequency of D and I alleles are 69.35% and 30.65%, respectively, in the total population. The analysis of allelic frequencies via Fisher's exact test confirmed significantly higher frequency of D allele in both severe groups than that in the mild one, 78.31% in Hospitalized patients (OR = 2.56; 95% CI 1.46 to 4.46; p-value = 0.0011) and 74.19% in Inpatients led to ICU/death (OR = 2.04; 95% CI = 1.22 to 3.43; p-value = 0.0094) compared to 58.45% in Outpatients. The results of genotype proportions displayed an association between COVID-19 severity and DD genotype. Overall, our findings in Iranian patients supported the undeniable role of the DD genotype in the intensity of the disease, comparable to other populations. Furthermore, there is no definite evidence regarding the protective effect of the I allele in our inquiry.

Etelcalcetide and Paricalcitol in Chronic Kidney Disease: When the Target Is Inflammation

Introduction: secondary hyperparathyroidism (SHP) is frequent in patients with chronic kidney disease (CKD), particularly in those in dialysis. To treat this complication, the current options available include phosphorus restriction, phosphate binders, the inhibition of parathyroid hormone (PTH) synthesis and secretion by the supplementation of vitamin D or VDR activators, or the use of calcimimetics. Beyond the control of PTH, the effects of the treatment of SHP on other biomarkers of risk may represent an additional benefit for this population. In this study, we explore the benefits of current SHP treatment options, mainly paricalcitol and/or etelcalcetide in the inflammatory state of hemodialysis (HD) patients. Results: the study finally included 142 maintenance HD patients (5 patients were excluded) followed for 6 months (dialysis vintage 26 ± 30 months, mean age 70 years old, 73% women, 81% Spanish white, 47% diabetic). In this case, 52 patients were on regular treatment with paricalcitol for SHP and 25 patients were eligible to initiate etelcalcetide. The baseline serum levels of Ca, P, PTH, Ferritin, albumin, C-reactive protein (CRP), and other variables were measured. We found serum PTH levels showed an improvement after the treatment with etelcalcetide again paricalcitol and no treatment (p < 0.04). Of note, serum levels of CRP were significantly lower in a small group of patients (n = 11) receiving paricalcitol + etelcalcetide compared to paricalcitol or etelcalcetide alone. The proportion of patients with CRP within target ranges (≤1.0 mg/dL) increased significantly after combined treatment (p < 0.001). Conclusions: etelcalcetide proved to safely reduce the PTH levels without significant adverse events and the possibility of a synergic anti-inflammatory effect with the simultaneous use of Paricalcitol in HD patients.

Head-to-Head Comparison of Oxidative Stress Biomarkers for All-Cause Mortality in Hemodialysis Patients

Oxidative stress (OS) presents even in the early chronic kidney disease (CKD) stage and is exacerbated in patients with end-stage renal disease (ESRD) undergoing maintenance hemodialysis (MHD). There is still a debate over the association between oxidative stress and mortality. Our study aims to compare head-to-head the prognostic value of different oxidative markers for all-cause mortality in hemodialysis (HD) patients. We thus enrolled 347 patients on HD in this prospective study. Four OS biomarkers were measured (carbonyl proteins, myeloperoxidase (MPO), advanced oxidation protein products (AOPPs), and oxidized low-density lipoprotein (ox-LDL)). During the 60-month follow-up period, 9 patients have been lost to follow-up and 168 (48.4%) patients died. Concerning the oxidative stress (ox-stress) byproducts, carbonyl proteins were lower in survivors (105.40 ng/mL (IQR 81.30−147.85) versus 129.65 ng/mL (IQR 93.20−180.33); p < 0.001), with similar results for male patients (103.70 ng/mL (IQR 76.90−153.33) versus 134.55 ng/mL (IQR 93.95−178.68); p = 0.0014). However, there are no significant differences in MPO, AOPP, and ox-LDL between the two groups. Kaplan−Meier survival analysis indicated that patients in the higher carbonyl proteins concentration (>117.85 ng/mL group) had a significantly lower survival rate (log-rank test, p < 0.001). Univariate Cox regression analysis showed a positive correlation between carbonyl proteins and all-cause mortality in the higher and lower halves. Even after adjustment for conventional risk factors, it remained a statistically significant predictor of an increased risk of death in MHD. Univariate Cox regression analysis of MPO showed that continuous MPO and Log MPO were significantly associated with all-cause mortality, except for binary MPO (divided according to the median of MPO). Multivariate Cox analysis for MPO showed that the mortality prediction remains significant after adjusting for multiple factors. In conclusion, not all ox-stress biomarkers predict all-cause mortality in HD patients to a similar extent. In the present study, carbonyl proteins and MPO are independent predictors of all-cause mortality in HD patients, whereas AOPPs and oxLDL are clearly not associated with all-cause mortality in HD patients.

Role of predictable biomarkers in early detection of cardiovascular events in Chronic Kidney Disease III and IV

This comes about because of a lack of predicted biomarkers in the risk analysis of CVD events in chronic kidney disease (CKD) patients. The present study aimed to determine the clinical utility of independent, predictable biomarkers such as serum creatinine, estimated Glomerular Filtration Rate (eGFR), high sensitive C-Reactive protein (hsCRP), fibrinogen and lipid profile as early predictors of CVD in CKD at stage III/IV.

Methods. This is a case-control study that includes a sample size of 100 patients of cases and 100 patients of controls who were recruited from November 2020 to April 2021, from the Nephrology department of the Visakhapatnam tertiary care teaching hospital, and present with chronic kidney disease – stage III/IV. The subjects’ general conditions (age, gender, height, weight, systolic blood pressure, diastolic blood pressure, and smoking history); underlying diseases (coronary heart disease and diabetes mellitus) were recorded. Fasting venous blood samples were collected under aseptic conditions from the study group after taking informed consent. The measurement of serum creatinine was performed by modification of kinetic Jaffe reaction. The Cockcroft-Gault equation was used to calculate eGFR in both cases and controls. CRP testing was done with a Cobas C311 analyzer, using immunoturbidimetric assay. The Fibroquant kit from Tulip was employed to measure fibrinogen levels in blood samples, and enzymatic methods were applied for lipid profile analysis.

Results. In this study, higher mean values of hsCRP (34.28 mg/dl), increased serum creatinine levels (2.876 mg/dl), reduced eGFR (28.37 mls/min), high levels of serum fibrinogen (291.6 mg/dl), and cholesterol (214.5 mg/dl), HDL (28.34 mg/dl), TG (162.1 mg/dl), VLDL (32.41 mg/dl) and LDL (153.77 mg/dl) were found to be independent predictors of assessment of CV events in patients with CKD stages III and IV as determined by Chi-square test.

Conclusion. A prompt and accurate assessment of cardiovascular risk in CKD patients would enable more aggressive and focused treatment of the individuals who are most in need of preventive interventions to decrease incident rates.

Circulating Omentin-1, Sustained Inflammation and Hyperphosphatemia at the Interface of Subclinical Atherosclerosis in Chronic Kidney Disease Patients on Chronic Renal Replacement Therapy

Background and Objectives: Subclinical atherosclerosis, reflected by abnormal carotid intima–media thickness (cIMT), is pervasive among chronic kidney disease patients on chronic renal replacement therapy (RRT), being mostly influenced by uremia-related rather than traditional risk factors. Materials and Methods: In this pilot study, we measured circulating levels of Omentin-1, a recently discovered adipokine with strong anti-atherogenic properties, in a heterogeneous cohort of 77 asymptomatic RRT individuals (40 chronic kidney transplant recipients, Ktx; and 37 chronic hemodialysis patients, HD) and in 30 age-matched controls. Results: Omentin-1 was increased in RRT individuals as compared with controls (p = 0.03). When stratifying for renal replacement modality, we found Ktx patients to have significantly lower Omentin-1 than HD patients (p = 0.01). Lower Omentin-1 levels were also found among RRT individuals with pathological cIMT (168.7 [51.1–457.8] vs. 474.9 [197.2–1432.1]; p = 0.004). Our multivariate correlations analysis revealed Omentin-1 as the most robust independent predictor of carotid atherosclerosis (β-0.687; p = 0.03), even more than total cholesterol, diastolic BP and age, and this adipokine was at the crossroad of a complex interplay with sustained inflammation (high CRP and ferritin) and hyperphosphatemia in predicting higher cIMT values. Conclusion: The findings reported extend to renal patients with advanced disease, with the possible involvement of Omentin-1 in the pathogenesis of atherosclerosis. This may set the stage for future interventional studies of Omentin-1 replacement to retard atherosclerosis progression, as it is currently being investigated in other disease settings.

Impact of Hemodialysis on Clinical Outcomes in Patients Undergoing Lower Extremity Bypass Surgery for Peripheral Artery Disease-10-year Follow-Up Study

We investigated the clinical impact of hemodialysis on long-term outcomes of bypass surgery in patients with peripheral artery disease. We evaluated 660 consecutive patients who underwent successful bypass surgery (392 hemodialysis and 268 non-hemodialysis). The endpoint was amputation-free survival (AFS). To minimize differences in clinical characteristics between the 2 groups, propensity score matching was performed. The AFS rates for 10-year follow-up were 39.3% and 67.7% in hemodialysis and non-hemodialysis patients [hazard ratio (HR) 2.21, 95% confidence interval (CI) 1.65-3.01, P < .0001]. Cumulative incidence of amputation was higher in the hemodialysis group than in the non-hemodialysis group [(19.4 vs 8.4%, HR 2.15, 95% CI 1.29-3.74, P = .0027). In a matched cohort (n = 210 each), AFS was still lower in the hemodialysis patients (53.1 vs 66.3%, HR 1.94, 95% CI 1.36-2.82, P = .0003). However, there was no significant difference in amputation rate between the groups (10.5 vs 10.6%, HR .97, 95% CI 0.49-1.87, P = .93). In a sub-analysis of patients with critical limb ischemia, similar results were obtained. The 10-year AFS was consistently lower in the hemodialysis group than in the non-hemodialysis group. However, the amputation rate was comparable between the groups when matched for the differences in clinical characteristics.

Polypharmacy, chronic kidney disease, and incident fragility fracture: a prospective cohort study

INTRODUCTION

Polypharmacy is associated with an increased risk of fracture in aging populations, but no study has accounted for the impact of kidney function on this association. This study aimed to examine the association between polypharmacy and incident fragility fracture based on chronic kidney disease (CKD) status.

MATERIALS AND METHODS

Participants were 2023 patients (55% men; mean age, 69 years) of Sado General Hospital enrolled in the Project in Sado for Total Health (PROST) between June 2008 and December 2016. Among these, 65%, 28%, and 7% had non-CKD, non-dialysis-dependent CKD, and dialysis-dependent CKD, respectively. Multivariable Cox proportional hazards analysis was conducted with adjustments for potential confounders.

RESULTS

Prevalences of polypharmacy (≥ 5 medications) and hyperpolypharmacy (≥ 10 medications) among participants were 43% and 9% for non-CKD, 62% and 23% for non-dialysis-dependent CKD, and 85% and 34% for dialysis-dependent CKD, respectively. During a median follow-up of 5.6 years, 256 fractures occurred. More medications were associated with a higher risk of fractures. Specifically, compared to participants without polypharmacy, adjusted hazard ratios were 1.32 (95% CI 0.96-1.79) and 1.99 (1.35-2.92) for those with polypharmacy and hyperpolypharmacy, respectively, after adjusting for osteoporosis risk factors, CKD status, and comorbidities. No effect modification by CKD status was observed (interaction P = 0.51). Population-attributable fractions of hyperpolypharmacy for fracture were 9.9% in the total cohort and 42.1% in dialysis-dependent CKD patients.

CONCLUSION

Hyperpolypharmacy is associated with an increased risk of fragility fracture regardless of CKD status, and has a strong impact on incident fragility fractures in dialysis-dependent CKD patients.

The Impact of Inflammation on the Immune Responses to Transplantation: Tolerance or Rejection?

Transplantation (Tx) remains the optimal therapy for end-stage disease (ESD) of various solid organs. Although alloimmune events remain the leading cause of long-term allograft loss, many patients develop innate and adaptive immune responses leading to graft tolerance. The focus of this review is to provide an overview of selected aspects of the effects of inflammation on this delicate balance following solid organ transplantation. Initially, we discuss the inflammatory mediators detectable in an ESD patient. Then, the specific inflammatory mediators found post-Tx are elucidated. We examine the reciprocal relationship between donor-derived passenger leukocytes (PLs) and those of the recipient, with additional emphasis on extracellular vesicles, specifically exosomes, and we examine their role in determining the balance between tolerance and rejection. The concept of recipient antigen-presenting cell "cross-dressing" by donor exosomes is detailed. Immunological consequences of the changes undergone by cell surface antigens, including HLA molecules in donor and host immune cells activated by proinflammatory cytokines, are examined. Inflammation-mediated donor endothelial cell (EC) activation is discussed along with the effect of donor-recipient EC chimerism. Finally, as an example of a specific inflammatory mediator, a detailed analysis is provided on the dynamic role of Interleukin-6 (IL-6) and its receptor post-Tx, especially given the potential for therapeutic interdiction of this axis with monoclonal antibodies. We aim to provide a holistic as well as a reductionist perspective of the inflammation-impacted immune events that precede and follow Tx. The objective is to differentiate tolerogenic inflammation from that enhancing rejection, for potential therapeutic modifications. (Words 247).

Predictors and outcomes of neoatherosclerosis in patients with in-stent restenosis

BACKGROUND

In-stent restenosis (ISR), especially for neoatherosclerosis, is still a major problem of percutaneous coronary intervention (PCI) even in the drug-eluting stent (DES) era.

AIMS

The purpose of this study was to investigate the impact of neoatherosclerosis on prognosis after PCI for ISR.

METHODS

Between March 2009 and December 2017, 313 ISR lesions in patients undergoing an OCT-guided PCI in five hospitals were retrospectively enrolled. Neoatherosclerosis was defined as a lipid neointima or calcified neointima. We examined the association between neoatherosclerosis and the clinically driven target lesion revascularisation (CD-TLR) rates.

RESULTS

In 313 ISR lesions, 64 lesions (20.4%) had bare metal stents and 241 lesions (77.0%) had drug-eluting stents (DES). Among them, 47.0% of lesions (147 lesions) had neoatherosclerosis. A multivariate logistic regression analysis demonstrated that eGFR (odds ratio [OR] 0.986, 95% confidence interval [CI]: 0.974-0.998; p=0.023), the time from PCI to the ISR (OR 1.13, 95% CI: 1.06-1.22; p<0.001) and DES-ISR (OR 2.48, 95% CI: 1.18-5.43; p=0.019) were independent predictors for neoatherosclerosis. A multivariate regression analysis demonstrated that neoatherosclerosis was an independent predictor of CD-TLR.

CONCLUSIONS

In this multicentre ISR registry, OCT imaging demonstrated that eGFR, the time from PCI to the ISR and DES-ISR were independent predictors for neoatherosclerosis and that neoatherosclerosis in ISR lesions had a worse impact on the CD-TLR rate.

Oxidative Stress in Non-Dialysis-Dependent Chronic Kidney Disease Patients

Background: Cardiovascular complications are the leading cause of morbidity and mortality at any stage of chronic kidney disease (CKD). Moreover, the high rate of cardiovascular mortality observed in these patients is associated with an accelerated atherosclerosis process that likely starts at the early stages of CKD. Thus, traditional and non-traditional or uremic-related factors represent a link between CKD and cardiovascular risk. Among non-conventional risk factors, particular focus has been placed on anaemia, mineral and bone disorders, inflammation, malnutrition and oxidative stress and, in this regard, connections have been reported between oxidative stress and cardiovascular disease in dialysis patients. Methods: We evaluated the oxidation process in different molecular lines (proteins, lipids and genetic material) in 155 non-dialysis patients at different stages of CKD and 45 healthy controls. To assess oxidative stress status, we analyzed oxidized glutathione (GSSG), reduced glutathione (GSH) and the oxidized/reduced glutathione ratio (GSSG/GSH) and other oxidation indicators, including malondialdehyde (MDA) and 8-oxo-2’-deoxyguanosine (8-oxo-dG). Results: An active grade of oxidative stress was found from the early stages of CKD onwards, which affected all of the molecular lines studied. We observed a heightened oxidative state (indicated by a higher level of oxidized molecules together with decreased levels of antioxidant molecules) as kidney function declined. Furthermore, oxidative stress-related alterations were significantly greater in CKD patients than in the control group. Conclusions: CKD patients exhibit significantly higher oxidative stress than healthy individuals, and these alterations intensify as eGFR declines, showing significant differences between CKD stages. Thus, future research is warranted to provide clearer results in this area.

Circulating Advanced Glycation End Products and Their Soluble Receptors in Relation to All-Cause and Cardiovascular Mortality: A Systematic Review and Meta-analysis of Prospective Observational Studies

Advanced glycation end products (AGEs) are involved in the development of several age-related complications. The protective role of soluble receptors for AGEs (sRAGE) against deleterious effects of AGEs has been indicated in several studies. However, findings on the association of AGEs or sRAGE with mortality are equivocal. In this meta-analysis we aimed to present a quantitative estimation of the association between circulating AGEs or sRAGE and all-cause or cardiovascular disease (CVD) mortality. A comprehensive literature search was performed to determine relevant publications through the online databases including PubMed, Scopus, and Web of Science up to 29 November 2020. Prospective observational studies assessing the association between circulating AGEs or sRAGE and all-cause or CVD mortality were included. Seven studies with a total of 3718 participants and 733 mortality cases (345 CVD deaths) were included in the meta-analysis for assessing the association between circulating AGEs and mortality. Our results showed that higher circulating AGEs were associated with increased risk of all-cause (pooled effect measure: 1.05; 95% CI: 1.01, 1.09; P = 0.018, I2 = 77.7%) and CVD mortality (pooled effect measure: 1.08; 95% CI: 1.01, 1.14; P = 0.015, I2 = 80.2%), respectively. The association between sRAGE and mortality was assessed in 14 studies with a total of 16,335 participants and 2844 mortality cases (419 CVD deaths). Serum concentrations of sRAGE were not associated with the risk of all-cause mortality (pooled effect measure: 1.01; 95% CI: 1.00, 1.01; P = 0.205, I2 = 75.5%), whereas there was a significant link between sRAGE and the risk of CVD mortality (pooled effect measure: 1.02; 95% CI: 1.00, 1.04; P = 0.02, I2 = 78.9%). Our findings showed that a higher serum AGE concentration was associated with increased risk of all-cause and CVD mortality. In addition, higher circulating sRAGE was related to increased risk of CVD mortality. This review was registered at PROSPERO as CRD42021236559.

COVID-19 in Chronic Kidney Disease: The Impact of Old and Novel Cardiovascular Risk Factors

Cardiovascular disease is a frequent complication and the most common cause of death in patients with CKD. Despite landmark medical advancements, mortality due to cardiovascular disease is still 20 times higher in CKD patients than in the general population, which is mainly due to the high prevalence of risk factors in this group. Indeed, in addition to traditional cardiovascular risk factors, CKD patients are exposed to nontraditional ones, which include metabolic, hormonal, and inflammatory alterations. The global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has brought novel challenges for both cardiologists and nephrologists alike. Emerging evidence indicates that coronavirus disease 2019 (COVID-19) increases the risk of cardiovascular events and that several aspects of the disease may synergize with pre-existing cardiovascular risk factors in CKD patients. A better understanding of these mechanisms is pivotal for the prevention and treatment of cardiovascular events in this context, and we believe that additional clinical and experimental studies are needed to improve cardiovascular outcomes in CKD patients with COVID-19. In this review, we provide a summary of traditional and nontraditional cardiovascular risk factors in CKD patients, discussing their interaction with SARS-CoV-2 infection and focusing on CO-VID-19-related cardiovascular complications that may severely affect short- and long-term outcomes in this high-risk population.

Non-traditional Risk Factors of Cardiovascular Disease and Coenzyme Q10 Therapy in Hemodialysis Patients

Background: Inflammatory markers increase in end-stage renal disease (ESRD), especially in diabetic patients, and are positively correlated with cardiovascular mortality. Coenzyme Q10 (CoQ10), an agent with antioxidant properties, may be effective in reducing cardiovascular complications in hemodialysis patients. This study aimed to investigate the effects of CoQ10 supplementation on plasma C-reactive protein (CRP), homocysteine, and albumin in hemodialysis patients. Methods: Forty diabetic ESRD patients on hemodialysis for at least six months were evaluated in a double-blinded randomized clinical trial. The patients were randomly assigned to one of the two groups to receive either CoQ10 100 mg daily or placebo. In all patients, the serum levels of homocysteine, albumin, and CRP were measured before and after six months. Results: The mean age of the patients was 60.3 ± 9.1 years, and 57.5% of the participants were female. There was no statistical difference between the two groups at baseline. Furthermore, no significant difference was observed in serum albumin (P = 0.843), CRP (P = 0.214), and homocysteine (P = 0.21) at the end of the intervention between the groups. Conclusions: This study showed that in patients with ESRD, using CoQ10 supplementation has minimal beneficial effects on serum albumin, CRP, and homocysteine levels.

Mortality analysis of COVID-19 infection in chronic kidney disease, haemodialysis and renal transplant patients compared with patients without kidney disease: a nationwide analysis from Turkey

Background

Chronic kidney disease (CKD) and immunosuppression, such as in renal transplantation (RT), stand as one of the established potential risk factors for severe coronavirus disease 2019 (COVID-19). Case morbidity and mortality rates for any type of infection have always been much higher in CKD, haemodialysis (HD) and RT patients than in the general population. A large study comparing COVID-19 outcome in moderate to advanced CKD (Stages 3–5), HD and RT patients with a control group of patients is still lacking.

Methods

We conducted a multicentre, retrospective, observational study, involving hospitalized adult patients with COVID-19 from 47 centres in Turkey. Patients with CKD Stages 3–5, chronic HD and RT were compared with patients who had COVID-19 but no kidney disease. Demographics, comorbidities, medications, laboratory tests, COVID-19 treatments and outcome [in-hospital mortality and combined in-hospital outcome mortality or admission to the intensive care unit (ICU)] were compared.

Results

A total of 1210 patients were included [median age, 61 (quartile 1–quartile 3 48–71) years, female 551 (45.5%)] composed of four groups: control (n = 450), HD (n = 390), RT (n = 81) and CKD (n = 289). The ICU admission rate was 266/1210 (22.0%). A total of 172/1210 (14.2%) patients died. The ICU admission and in-hospital mortality rates in the CKD group [114/289 (39.4%); 95% confidence interval (CI) 33.9–45.2; and 82/289 (28.4%); 95% CI 23.9–34.5)] were significantly higher than the other groups: HD = 99/390 (25.4%; 95% CI 21.3–29.9; P < 0.001) and 63/390 (16.2%; 95% CI 13.0–20.4; P < 0.001); RT = 17/81 (21.0%; 95% CI 13.2–30.8; P = 0.002) and 9/81 (11.1%; 95% CI 5.7–19.5; P = 0.001); and control = 36/450 (8.0%; 95% CI 5.8–10.8; P < 0.001) and 18/450 (4%; 95% CI 2.5–6.2; P < 0.001). Adjusted mortality and adjusted combined outcomes in CKD group and HD groups were significantly higher than the control group [hazard ratio (HR) (95% CI) CKD: 2.88 (1.52–5.44); P = 0.001; 2.44 (1.35–4.40); P = 0.003; HD: 2.32 (1.21–4.46); P = 0.011; 2.25 (1.23–4.12); P = 0.008), respectively], but these were not significantly different in the RT from in the control group [HR (95% CI) 1.89 (0.76–4.72); P = 0.169; 1.87 (0.81–4.28); P = 0.138, respectively].

Conclusions

Hospitalized COVID-19 patients with CKDs, including Stages 3–5 CKD, HD and RT, have significantly higher mortality than patients without kidney disease. Stages 3–5 CKD patients have an in-hospital mortality rate as much as HD patients, which may be in part because of similar age and comorbidity burden. We were unable to assess if RT patients were or were not at increased risk for in-hospital mortality because of the relatively small sample size of the RT patients in this study.

Magnesium Sulfate Improves Some Risk Factors for Atherosclerosis in Patients Suffering from One or Two Coronary Artery Diseases: A Double-blind Clinical Trial Study

Purpose

Given the beneficial effect of MgSO₄ on the cardiovascular system, this study was designed to investigate the effect of MgSO₄ administration on suppressing some atherosclerotic risk factors in moderate coronary artery disease patients with one or two atherosclerotic vessels.

Patients and Methods

In a randomized double-blind placebo-controlled clinical trial study, 64 patients with moderate coronary artery disease (55–69% stenosis) were selected according to angiography findings. Patients were divided into four groups including patients with one or two atherosclerotic vessels treated with MgSO₄ (Mg-treated-VR1, Mg-treated-VR2, respectively), placebo treated patients with one or two atherosclerotic vessels (Control-VR1, Control-VR2, respectively). The patients received either placebo or MgSO₄ supplement capsule containing 300 mg MgSO₄ for six months on a daily basis. ESR, Ca/Mg ratio, urine Mg level, serum Mg, fibrinogen, homocysteine, uric acid, Na, K, Ca, CRP, T3, T4, TSH, BUN, and Cr concentrations were measured at baseline and every three months.

Results

Serum T3, Ca, K, homocysteine, CRP, and Mg concentrations were significantly improved in Mg-treated groups compared to placebo groups.

Conclusion

The results of this study showed that despite the slight change in serum magnesium level, oral administration of MgSO₄for six months could slightly reduce the serum levels of some inflammatory and vascular factors in moderate coronary artery disease patients.

Pathophysiological Mechanisms by which Heat Stress Potentially Induces Kidney Inflammation and Chronic Kidney Disease in Sugarcane Workers

BACKGROUND

Chronic kidney disease of non-traditional origin (CKDnt) is common among Mesoamerican sugarcane workers. Recurrent heat stress and dehydration is a leading hypothesis. Evidence indicate a key role of inflammation.

METHODS

Starting in sports and heat pathophysiology literature, we develop a theoretical framework of how strenuous work in heat could induce kidney inflammation. We describe the release of pro-inflammatory substances from a leaky gut and/or injured muscle, alone or in combination with tubular fructose and uric acid, aggravation by reduced renal blood flow and increased tubular metabolic demands. Then, we analyze longitudinal data from >800 sugarcane cutters followed across harvest and review the CKDnt literature to assess empirical support of the theoretical framework.

RESULTS

Inflammation (CRP elevation and fever) and hyperuricemia was tightly linked to kidney injury. Rehydrating with sugary liquids and NSAID intake increased the risk of kidney injury, whereas electrolyte solution consumption was protective. Hypokalemia and hypomagnesemia were associated with kidney injury.

DISCUSSION

Heat stress, muscle injury, reduced renal blood flow and fructose metabolism may induce kidney inflammation, the successful resolution of which may be impaired by daily repeating pro-inflammatory triggers. We outline further descriptive, experimental and intervention studies addressing the factors identified in this study.

Detection of renal biomarkers in chronic kidney disease using microfluidics: progress, challenges and opportunities

Chronic kidney disease (CKD) typically evolves over many years in a latent period without clinical signs, posing key challenges to detection at relatively early stages of the disease. Accurate and timely diagnosis of CKD enable effective management of the disease and may prevent further progression. However, long turn-around times of current testing methods combined with their relatively high cost due to the need for established laboratory infrastructure, specialized instrumentation and trained personnel are drawbacks for efficient assessment and monitoring of CKD, especially in underserved and resource-poor locations. Among the emerging clinical laboratory approaches, microfluidic technology has gained increasing attention over the last two decades due to the possibility of miniaturizing bioanalytical assays and instrumentation, thus potentially improving diagnostic performance. In this article, we review current developments related to the detection of CKD biomarkers using microfluidics. A general trend in this emerging area is the search for novel, sensitive biomarkers for early detection of CKD using technology that is improved by means of microfluidics. It is anticipated that these innovative approaches will be soon adopted and utilized in both clinical and point-of-care settings, leading to improvements in life quality of patients.

Incidental detection of Corynebacterium jeikeium endocarditis via regular blood examination in an afebrile hemodialysis patient

Herein, we describe a rare case of Corynebacterium jeikeium endocarditis that silently progressed in a 65-year-old man undergoing hemodialysis. Because routine monthly blood examination revealed high C-reactive protein levels, blood cultures were collected, although he had no symptom and was afebrile. After 2 days, a Gram-positive rod was detected in one set of the blood culture. Furthermore, transthoracic echocardiography revealed new aortic regurgitation (AR) and vegetations, and, therefore, infective endocarditis was suspected. Transesophageal echocardiography showed vegetations with a maximum diameter of 8 mm on his aortic valve, with some valve destruction. C. jeikeium was identified in three sets of blood cultures. Administration of daptomycin was started because he had vancomycin allergy. Judging from the high risk of embolization due to vegetations, emergency aortic valve replacement was performed on the second day. C. jeikeium was detected in a resected cardiac valve specimen and blood. This case emphasizes that physicians should always consider the possibility of infective endocarditis even in hemodialysis patients without any symptoms.

Workload and cross-harvest kidney injury in a Nicaraguan sugarcane worker cohort

Objectives

To examine the association between workload and kidney injury in a fieldworker cohort with different levels of physically demanding work over a sugarcane harvest, and to assess whether the existing heat prevention efforts at a leading occupational safety and health programme are sufficient to mitigate kidney injury.

Methods

Biological and questionnaire data were collected before (n=545) and at the end (n=427) of harvest among field support staff (low workload), drip irrigation workers (moderate), seed cutters (high) and burned sugarcane cutters (very high). Dropouts were contacted (87%) and reported the reason for leaving work. Cross-harvest incident kidney injury (IKI) was defined as serum creatinine increase ≥0.30 mg/dL or ≥1.5 times the baseline value, or among dropouts reporting kidney injury leading to leaving work.

Results

Mean cross-harvest estimated glomerular filtration rate change was significantly associated with workload, increasing from 0 mL/min/1.73 m² in the low-moderate category to −5 mL/min/1.73 m² in the high and −9 mL/min/1.73 m² in the very high workload group. A similar pattern occurred with IKI, where low-moderate workload had 2% compared with 27% in the very high workload category. A healthy worker selection effect was detected, with 32% of dropouts reporting kidney injury. Fever and C reactive protein elevation were associated with kidney injury.

Conclusions

Workers considered to have the highest workload had more cross-harvest kidney damage than workers with less workload. Work practices preventing heat stress should be strengthened and their role in preventing kidney damage examined further. Future occupational studies on chronic kidney disease of unknown aetiology should account for a healthy worker effect by pursuing those lost to follow-up.

Superior Patient Survival for Continuous Ambulatory Peritoneal Dialysis Patients Treated with a Peritoneal Dialysis Fluid with Neutral pH and Low Glucose Degradation Product Concentration (Balance)

Background

In recent years, laboratory and clinical research has suggested the need for peritoneal dialysis fluids (PDFs) that are more biocompatible than the conventional PDFs commonly used today. Bioincompatibility of PDF has been attributed to low pH, lactate, glucose, glucose degradation products (GDPs), and osmolality. PDFs with neutral pH and low GDPs are now available commercially. In vitro and early clinical studies suggest that these solutions are indeed more biocompatible but, as of now, there is no evidence that their use improves patient outcome.

Methods

Using a dedicated database of over 2000 patients treated with PD in Korea, we were able to conduct a retrospective observational study comparing outcomes for incident continuous ambulatory PD patients treated with a standard, conventional, heat-sterilized PDF to the outcomes for patients treated with a novel, low GDP, neutral-pH PDF prepared in a dual-compartment, double-bag PD system (Balance; Fresenius Medical Care, St. Wendel, Germany). In an intention-to-treat analysis, patient and technique survival, peritonitis-free survival, and peritonitis rates were compared in 611 patients treated with Balance for up to 30 months and 551 patients with a standard PDF (stay·safe; Fresenius Medical Care) treated in the same era and with equivalent follow-up.

Results

The patients were well matched for most relevant characteristics except older age distribution for the patients treated with the standard PDF. Patients treated with Balance had significantly superior survival compared to those treated with the standard PDF (74% vs 62% at 28 months, p = 0.0032). In a multivariate Cox regression model including age, diabetes, and gender, the survival advantage persisted (relative risk of death for Balance 0.75, 95% confidence interval 0.56 – 0.99, p = 0.0465). Modality technique survival was similar in Kaplan–Meier analysis for both PDFs. No differences were detected in peritonitis-free survival or in peritonitis rates between the two solutions.

Conclusion

This study, for the first time, suggests that treatment with a novel biocompatible PDF with low GDP concentration and neutral pH confers a significant survival advantage. The exact mechanisms for such a survival advantage cannot be determined from this study. The usual criticisms of observational studies apply and the results reported here strongly warrant the undertaking of appropriately designed, randomized, controlled clinical trials.

C-Reactive Protein and Anti-Chlamydia Pneumoniae Antibodies as Risk Factors of Cardiovascular Death in Incident Patients on Peritoneal Dialysis

Objective

Recently it has been pointed out that inflammation and infections caused by germs such as Chlamydia pneumoniae are independent cardiovascular risk factors for the general population, but information about these relationships in dialysis patients is scarce. This work was done to analyze the association of C-reactive protein (CRP) and IgG anti- Chlamydia pneumoniae antibodies (anti-Chlp-IgG) as independent cardiovascular risk factors in incident patients on continuous ambulatory peritoneal dialysis (CAPD).

Design

Single-cohort, prospective observational study.

Setting

Three CAPD centers from the Instituto Mexicano del Seguro Social, and one from the Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico.

Patients

A cohort of 75 adult incident patients on CAPD, without clinical signs of congestive heart failure, coronary heart disease, or peripheral arterial insufficiency. No restrictions for age, gender, or cause of renal failure were applied.

Primary Outcome

Mortality.

Methods

Demographic variables, body composition by electrical bioimpedance, serum glucose, urea, creatinine, lipids, homocysteine, nutritional markers (albumin, prealbumin, and transferrin), CRP, and anti-Chlp-IgG were measured and registered at the time of the first admission. When a patient died, the cause of death was determined by review of the clinical chart.

Results

Mean follow-up time was 10.25 patient-months. There were 14 cardiovascular deaths. CRP was positive (> 10 mg/L) in 64% of the patients, and anti-Chlp-IgG in 64%; 29% of the patients were positive for both markers. The relative risk for cardiovascular mortality was 6.23 for patients positive for either CRP or anti-Chlp-IgG, and increased to 9.52 when both markers were positive. Multivariate analysis revealed that CRP and anti-Chlp-IgG were stronger cardiovascular death predictors than age, diabetes, and nutritional status.

Conclusion

These data suggest that inflammation and the presence of Chlamydia pneumoniae infections are important predictors of cardiovascular death in patients on CAPD.

The Time Course of Serum C-Reactive Protein is More Predictive of Mortality than its Baseline Level in Peritoneal Dialysis Patients

Background

Several recent studies reported that a high baseline serum C-reactive protein (CRP) is a powerful predictor of mortality in dialysis patients. However, the acute-phase response is intermittent and not a continuous feature in an individual patient. The aim of this prospective study was to determine whether serial analysis of serum CRP during follow-up allows better prediction of mortality and echocardiographic cardiac disease than a single baseline measurement in peritoneal dialysis (PD) patients.

Methods

97 PD patients were monitored for 3 years from the beginning of the treatment. We evaluated the effect of demographic features, comorbidity, blood pressure, blood biochemistry, including CRP, residual renal function, and indices of dialysis adequacy, on mortality and left ventricular hypertrophy (LVH). Cox regression analysis using both the baseline and the averaged values of the study parameters was carried out to determine factors predicting mortality. Logistic regression analysis was performed to determine which factors were independently predictive for LVH and the type of time course of serum CRP.

Results

Baseline serum CRP was elevated in 29 patients (29.9%). While serum CRP exhibited a stable course (normal or high) in 55 patients (56.7%), it varied considerably over time in 42 patients (43.2%). In the Cox models, both the averaged serum CRP and the type of variability of CRP were predictors of mortality. On the contrary, baseline CRP did not affect adjusted survival. The averaged CRP was also an independent factor affecting LVH, but baseline CRP was not. Age, comorbidity index, instilled dialysate glucose concentration, and Kt/V urea were independently associated with the type of time course of serum CRP.

Conclusion

The averaged value of serum CRP is more predictive of prognosis compared to the baseline value in PD patients. Determining serum CRP on a regular basis may be helpful to detect early signs of tissue damage or asymptomatic inflammation.

Aortic Valve Calcium Associates with All-Cause Mortality Independent of Coronary Artery Calcium and Inflammation in Patients with End-Stage Renal Disease

BACKGROUND

Aortic valve calcium (AVC) and coronary artery calcium (CAC) are common complications in end-stage renal disease (ESRD). We investigated the prognostic significance of overlapping presence of AVC and CAC, and whether AVC was associated with all-cause mortality independent of the presence of CAC in ESRD.

METHODS

259 ESRD patients (median age 55 years, 67% males) undergoing cardiac computed tomography were included. Framingham risk score (FRS), presence of cardiovascular disease (CVD), statin use, nutritional status and other relevant laboratory data were determined at baseline. During follow-up for median 36 months, 44 patients died, and 68 patients underwent renal transplantation.

RESULTS

The baseline overlap presence of AVC and CAC was 37%. Multivariate regression analysis showed that FRS (odds ratio (OR) 2.25; 95% confidence interval (95% CI), 1.43-3.55) and CAC score (OR (95% CI), 2.18 (1.34-3.59)) were independent determinants of AVC. In competing-risk regression models adjusted for presence of CAC, inflammation, nutritional status, CVD, FRS and statin use, AVC remained independently associated with all-cause mortality (sub-hazard ratio (95% CI), 2.57 (1.20-5.51)).

CONCLUSIONS

The overlap of AVC and CAC was 37% in this ESRD cohort. AVC was associated with increased all-cause mortality independent of presence of CAC, traditional risk factors and inflammation.

Inflammation and Extracellular Volume Expansion are Related to Sodium and Water Removal in Patients on Peritoneal Dialysis

Background

Inflammation is an important risk for mortality in dialysis patients. Extracellular fluid volume (ECFv) expansion, a condition commonly seen in peritoneal dialysis (PD) patients, may be associated with inflammation. However, published support for this relationship is scarce.

Objectives

To quantify the proportion of patients on PD with inflammation and to analyze the role of ECFv expansion and the factors related to these conditions.

Design

A prospective, multicenter cross-sectional study in six hospitals with a PD program.

Patients and Methods

Adult patients on PD were studied. Clinical data, body composition, and sodium and fluid intake were recorded. Biochemical analysis, C-reactive protein (CRP), and peritoneal and urinary fluid and sodium removal were also measured.

Results

CRP values positive (≥ 3.0 mg/L) for inflammation were found in 147 (80.3%) and negative in 36 patients. Patients with positive CRP had higher ECFv/total body water (TBW) ratio (women 47.69 ± 0.69 vs 47.36 ± 0.65, men 43.15 ± 1.14 vs 42.84 ± 0.65; p < 0.05), higher serum glucose (125.09 ± 81.90 vs 103.28 ± 43.30 mg/dL, p < 0.03), and lower serum albumin (2.86 ± 0.54 vs 3.17 ± 0.38 g/dL, p < 0.001) levels. They also had lower ultrafiltration (1003 ± 645 vs 1323 ± 413 mL/day, p < 0.005) and total fluid removal (1260 ± 648 vs 1648 ± 496 mL/day, p < 0.001), and less peritoneal (15.59 ± 162.14 vs 78.11 ± 110.70 mEq/day, p < 0.01) and total sodium removal (42.06 ± 142.49 vs 118.60 ± 69.73 mEq/day, p < 0.001). In the multivariate analysis, only ECFv/TBW was significantly ( p < 0.04) and independently associated with inflammation. ECFv/TBW was correlated with fluid removal ( r = 0.16, p < 0.03) and renal sodium removal ( r = 0.2, p < 0.01).

Conclusion

The data suggest that ECFv expansion may have a significant role as an inflammatory stimulus. The results disclose a relationship between the two variables, ECFv expansion and inflammation, identified as independent risk factors for mortality in PD patients.

The “Heart” of Peritoneal Dialysis: Residual Renal Function

The CANUSA study originally reported the importance of total small-solute clearance in predicting survival of peritoneal dialysis (PD) patients. However, subsequent reanalysis of data from the CANUSA study clearly demonstrated that the predictive power for mortality in PD patients was largely attributable to residual renal function (RRF) and not to the dose of PD. While this should not lead to the assumption that the dose of PD is unimportant, it does clearly indicate that the contribution of residual renal clearance and PD clearance to the overall survival of PD cannot be considered equivalent. In a previous study, we also demonstrated the importance of loss of RRF in predicting a heightened risk of mortality and cardiovascular death in PD patients. In this review, we focus our discussion on the different potential mechanisms that explain the important link between RRF and cardiovascular disease and survival of PD patients. We provide evidence to explain why RRF is so important to patients receiving long-term PD treatment and why it should be regarded as the “heart” of PD.

Lipid Profiling of Serum and Lipoprotein Fractions in Response to Pitavastatin Using an Animal Model of Familial Hypercholesterolemia

Statins are widely used for the treatment of atherosclerotic cardiovascular diseases. They inhibit cholesterol biosynthesis in the liver and cause pleiotropic effects, including anti-inflammatory and antioxidant effects. To develop novel therapeutic drugs, the effect of blood-borne lipid molecules on the pleiotropic effects of statins must be elucidated. Myocardial infarction-prone Watanabe heritable hyperlipidemic (WHHLMI) rabbits, an animal model for hypercholesterolemia, are suitable for the determination of lipid molecules in the blood in response to statins because their lipoprotein metabolism is similar to that of humans. Herein, lipid molecules were investigated by lipidome analysis in response to pitavastatin using WHHLMI rabbits. Various lipid molecules in the blood were measured using a supercritical fluid chromatography triple quadrupole mass spectrometry. Cholesterol and cholesterol ester blood concentrations decreased by reducing the secretion of very low density lipoproteins from the liver. Independent of the inhibition effects of cholesterol biosynthesis, the concentrations of some lipids with anti-inflammation and antioxidant effects (phospholipid molecules with n-6 fatty acid side chains, lysophosphatidylcholines, phosphatidylethanolamine plasmalogens, and ceramide molecules) were significantly altered. These findings may lead to further investigation of the mechanism of statin action.

Skin Autofluorescence-Indicated Advanced Glycation End Products as Predictors of Cardiovascular and All-Cause Mortality in High-Risk Subjects: A Systematic Review and Meta-analysis

Background

Chronic deposits of advanced glycation end products produced by enzymatic glycation have been suggested as predictors of atherosclerotic‐related disorders. This study aimed to estimate the relationship between advanced glycation end products indicated by skin autofluorescence levels and the risk of cardiovascular and all‐cause mortality based on data from observational studies.

Methods and Results

We systematically searched Medline, Embase, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and the Web of Science databases from their inceptions until November 2017 for observational studies addressing the association of advanced glycation end products by skin autofluorescence levels with cardiovascular and all‐cause mortality. The DerSimonian and Laird random‐effects method was used to compute pooled estimates of hazard ratios and their respective 95% confidence intervals for the risk of cardiovascular and all‐cause mortality associated with levels of advanced glycation end products by skin autofluorescence. Ten published studies were included in the systematic review and meta‐analysis. Higher skin autofluorescence levels were significantly associated with a higher pooled risk estimate for cardiovascular mortality (hazard ratio: 2.06; 95% confidence interval, 1.58–2.67), which might not be important to moderate heterogeneity (I²=34.7%; P=0.163), and for all‐cause mortality (hazard ratio: 1.91; 95% confidence interval, 1.42–2.56) with substantial heterogeneity (I²=60.8%; P=0.0.18).

Conclusions

Our data suggest that skin autofluorescence levels could be considered predictors of all‐cause mortality and cardiovascular mortality in patients at high and very high risk.

Dietary patterns and risk of incident chronic kidney disease: the Atherosclerosis Risk in Communities study

BACKGROUND

Adherence to healthy dietary patterns, measured by the Healthy Eating Index (HEI), Alternative Healthy Eating Index (AHEI), and alternate Mediterranean diet (aMed) scores, is associated with a reduced risk of cardiovascular disease. The association between these scores and chronic kidney disease (CKD) is undetermined.

OBJECTIVE

We aimed to estimate the association between the HEI, AHEI, and aMed scores and risk of incident CKD.

METHODS

We conducted a prospective analysis in 12,155 participants aged 45-64 y from the Atherosclerosis Risk in Communities (ARIC) Study. We calculated HEI-2015, AHEI-2010, and aMed scores for each participant and categorized them into quintiles of each dietary score. Incident CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73 m2 accompanied by ≥25% decline in estimated glomerular filtration rate, a kidney disease-related hospitalization or death, or end-stage renal disease. We used cause-specific hazard models to estimate risk of CKD from the quintile of the dietary score through to 31 December 2017.

RESULTS

There were 3980 cases of incident CKD over a median follow-up of 24 y. Participants who had higher adherence to the HEI-2015, AHEI-2010, and aMed scores were more likely to be female, have higher educational attainment, higher income level, be nonsmokers, more physically active, and diabetic compared with participants who scored lower. All 3 dietary scores were associated with lower CKD risk (P-trend < 0.001). Participants who were in the highest quintile of HEI-2015 score had a 17% lower risk of CKD (HR: 0.83; 95% CI: 0.74, 0.92) compared with participants in the lowest quintile. Those in quintile 5 of AHEI-2010 and aMed scores, respectively, had a 20% and 13% lower risk of CKD compared with those in quintile 1.

CONCLUSION

Higher adherence to healthy dietary patterns during middle age was associated with lower risk of CKD.

Cardiorenal Syndrome and Heart Failure-Challenges and Opportunities

Cardiorenal syndromes (CRS) describe concomitant bidirectional dysfunction of the heart and kidneys in which 1 organ initiates, perpetuates, and/or accelerates decline of the other. CRS are common in heart failure and universally portend worsened prognosis. Despite this heavy disease burden, the appropriate diagnosis and classification of CRS remains problematic. In addition to the hemodynamic drivers of decreased renal perfusion and increased renal vein pressure, induction of the renin-angiotensin-aldosterone system, stimulation of the sympathetic nervous system, disruption of balance between nitric oxide and reactive oxygen species, and inflammation are implicated in the pathogenesis of CRS. Medical therapy of heart failure including renin-angiotensin-aldosterone system inhibition and β-adrenergic blockade can blunt these deleterious processes. Renovascular disease can accelerate the progression of CRS. Volume overload and diuretic resistance are common and complicate the management of CRS. In heart failure and CRS being treated with diuretics, worsening creatinine is not associated with worsened outcome if clinical decongestion is achieved. Adjunctive therapy is often required in the management of volume overload in CRS, but evidence for these therapies is limited. Anemia and iron deficiency are importantly associated with CRS and might amplify decline of cardiac and renal function. End-stage cardiac and/or renal disease represents an especially poor prognosis with limited therapeutic options. Overall, worsening renal function is associated with significantly increased mortality. Despite progress in the area of CRS, there are still multiple pathophysiological and clinical aspects of CRS that need further research to eventually develop effective therapeutic options.

Adverse outcomes after non urological surgeries in patients with chronic kidney disease: a propensity-score-matched study

Objective

To evaluate the complications, mortality, and medical expenditures after nonurological surgical procedures in patients with chronic kidney disease (CKD).

Methods

Using claims data of Taiwan’s National Health Insurance, we conducted a matched cohort study of 35,643 patients with CKD who underwent nonurological surgeries in 2008–2013. By using a propensity-score matching procedure, 35,643 non-CKD patients were selected for comparison. Logistic regression was used to calculate the odds ratios (ORs) and the 95% confidence intervals (CIs) of postoperative complications and in-hospital mortality associated with CKD.

Results

The results showed that patients with CKD had higher risks of postoperative septicemia (OR: 1.78, 95% CI: 1.68–1.89), pneumonia (OR: 1.60, 95% CI: 1.48–1.73), stroke (OR: 1.34, 95% CI: 1.24–1.44), and in-hospital mortality (OR: 2.17, 95% CI: 1.90–2.47) compared with non-CKD patients. Longer hospital stays and higher medical expenditures after nonurological surgical procedures were noted in CKD patients. The association between CKD and postoperative adverse events was significant in both sexes, all of the age groups, and the other subgroups. Histories of myocardial infarction, epilepsy, and ages greater than 70 years were factors that were significantly associated with postoperative adverse events.

Conclusion

Compared with non-CKD patients, surgical patients with CKD exhibited more adverse events, with risks of in-hospital mortality that were approximately 2-fold higher after nonurinary surgery. These findings suggest an urgent need to revise the protocols for postoperative care in this population.

Cardiorenal Syndrome: Pathophysiology

Cardiorenal syndrome commonly refers to the collective dysfunction of heart and kidney resulting in a cascade of feedback mechanism causing damage to both the organs and is associated with adverse clinical outcomes. The pathophysiology of cardiorenal syndrome is complex, multifactorial, and dynamic. Improving the understanding of disease mechanisms will aid in developing targeted pharmacologic and nonpharmacologic therapies for the management of this syndrome. This article discusses the various mechanisms involved in the pathophysiology of the cardiorenal syndrome.

Intima-media thickness of the common carotid arteries as a marker of retinopathy and nephropathy in sickle cell disease

Purpose

This study was conducted to test the hypothesis that the carotid intima-media thickness (CIMT) is higher in patients with sickle cell disease (SCD) than in the normal population, and to determine the relationships of the CIMT with central retinal artery (CRA) and renal artery Doppler indices.

Methods

Forty-four confirmed steady-state SCD patients aged 16 years and above were recruited consecutively. The Doppler velocimetric indices of their right renal artery and both CRAs were obtained. The CIMT was also measured on each side via B-mode ultrasonography. The subjects were categorized by age and sex. Mean and median values for each group were determined. The Spearman correlation test was used to quantify the relationships between CIMT and the Doppler parameters.

Results

The participants had a median age of 24.50 years (interquartile range, 12.50 to 36.50 years). Twenty-three were men (52.3%) and 21 were women (47.7%). The median CIMT was 0.70 mm (IQR, 0.50 to 0.90 mm). Significant correlations with the CIMT were found for the CRA peak systolic velocity (r=0.312, P=0.003), the renal artery resistivity index (RI) (r=0.284, P=0.007), and the renal artery pulsatility index (PI) (r=0.273, P=0.010). There was no significant relationship between the CIMT and the CRA end-diastolic velocity, CRA RI, or CRA PI.

Conclusion

CIMT in SCD patients was higher than in the previously reported age groups of the reference populations. In addition, the CIMT was significantly correlated with the CRA peak systolic velocity, the renal artery RI, and the renal artery PI.

Long Pentraxin 3 as a Broader Biomarker for Multiple Risk Factors in End-Stage Renal Disease: Association with All-Cause Mortality

Persistent inflammation in end-stage renal disease (ESRD) patients is known to underlie the progression of chronic kidney disease and to be associated with multiple risk factors including malnutrition, atherosclerosis, and cardiovascular disease (CVD). The acute-phase protein pentraxin 3 (PTX3) has a proven potential as a local inflammatory biomarker, but its clinical utility in ESRD remains unclear. Circulating levels of PTX3 and classical inflammatory mediators, including the clinical prototypical C-reactive protein (CRP), were assessed in 246 ESRD patients on dialysis and analysed in relation to the lipid profile, adipokine levels, and nutritional, cardiac, and renal fibrosis markers. Occurrence of deaths was recorded for the following year. Contrarily to the classical inflammatory markers, PTX3 levels were negatively correlated with nutritional markers and associated with a less atherogenic lipid profile. Levels of the cardiac and renal fibrosis markers and of the oxidized LDL/LDL-C ratio were found to be independent determinants of PTX3 concentration. When comparing inflammatory mediators, the increase in the PTX3 levels was the only predictor of all-cause mortality in dialysis patients in a survival model adjusted to all markers under study, other than the inflammatory ones, besides common confounding factors in dialysis. Data support the clinical applicability of PTX3 as a broader inflammatory biomarker than the classical ones, presenting a close association with inflammation, malnutrition, CVD, and renal fibrosis and a great potential to predict all-cause mortality in dialysis patients. The pleiotropic character of PTX3 may be of clinical relevance, and it could be targeted to ameliorate the high morbidity and mortality associated with ESRD.

Risk factors for catheter-related infections in patients receiving permanent dialysis catheter

Background

Due to rising vascular comorbidities of patients undergoing dialysis, the prevalence of permanent hemodialysis catheters as hemodialysis access is increasing. However, infection is a major complication of these catheters. Therefore, identification of potential predicting risk factors leading to early infection related complications is valuable, in particular the significance the CRP (C-reactive protein)-value is of interest.

Methods

In this retrospective study 151 permanent hemodialysis catheters implanted in 130 patients were examined. The following data were collected at the time of catheter implantation: CRP-value, history of catheter-related infection, microbiological status, immunosuppression and diabetes mellitus. The primary outcomes were recorded over the 3 months following the implantation: catheter-related infection, days of hospital stay and death. Catheter removal or revision, rehospitalization and use of antibiotics were identified as secondary outcomes.

Results

We identified a total of 27 (17.9%) infections (systemic infection: 2.26 episodes/ 1000 catheter days, local infection: 0.6 episodes/ 1000 catheter days). The development of an infection was independent of the CRP-value (p = 0.66) as well as the presence of diabetes mellitus (p = 0.64) or immunosuppression (p = 0.71). Univariate analysis revealed that infection was more frequent in patients with MRSA-carriage (p < 0.001), in case of previous catheter-related infection (p < 0.05) and of bacteremia or bacteriuria in the period of 3 months before catheter implantation (p < 0.001). Catheter removal or revision (p = 0.002), rehospitalization (p = 0.001) and use of antibiotics (p = 0.02) were also more often observed in patients with MRSA-carriage.

Conclusions

The CRP-value at the time of implantation of a permanent hemodialysis catheter is not associated with the development of early catheter related infections, but an individual history of catheter-related infection, MRSA-carriage and bacteremia or bacteriuria in the period of 3 months prior to catheter implantation are significant risk factors.

Ankle-brachial index, arterial stiffness, and biomarkers in the prediction of mortality and outcomes in patients with end-stage kidney disease

BACKGROUND

Although ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) are significant predictors of major adverse cardiovascular event (MACE), their prognostic value in association with biomarkers has not been fully evaluated in patients with end-stage kidney disease (ESKD).

HYPOTHESIS

We hypothesized that ABI/baPWV would provide better prognostic value independent of biomarkers in ESKD patients.

METHODS

This study included 104 ESKD patients treated with maintenance hemodialysis who underwent ABI and baPWV examinations and laboratory tests, including brain-natriuretic peptide, high-sensitive cardiac troponin T (hs-cTnT), and high-sensitive C-reactive protein (hs-CRP). MACE was defined as a composite event of all-cause death, acute coronary syndrome, and stroke.

RESULTS

During a mean follow-up of 3.6 ± 1.7 years, a total of 51 MACE were observed. The independent factors associated with MACE were age >75 years (adjusted hazard ratio [HR], 2.15; P < .05), abnormal ABI (adjusted HR, 2.01; P < .05), left ventricular ejection fraction (LVEF) <50% (adjusted HR, 3.33; P < .001), the upper tertile of hs-cTnT (adjusted HR, 2.77; P < .05), and hs-CRP (HR, 1.96; P < .05). However, baPWV did not remain as an independent predictor of MACE in the entire cohort and also in patients without abnormal ABI. The combination of predictors improves the predictive value of MACE, providing increased HR with 4.00 for abnormal ABI + hs-CRP, 4.42 for abnormal ABI + hs-cTnT, and 7.04 for abnormal ABI + LVEF <50% (all P < .001).

CONCLUSION

Abnormal ABI is a robust predictor of MACE independent of biomarkers and their combination provides better risk stratification compared with a single predictor in ESKD patients.

C-reactive protein as a prognostic risk factor for loss of arteriovenous fistula patency in hemodialyzed patients

BACKGROUND

Inflammation is a cardiovascular risk factor in hemodialysis patients, but its influence on vascular access patency is still debatable. Our prospective study investigated this issue.

METHODS

A total of 258 patients receiving an arteriovenous fistula (AVF) between 2006 and 2016 at the Municipal Hospital Arad were included. Demographic, clinical, and laboratory characteristics were collected at the time of creation of the AVF. The primary study end point was AVF patency loss, defined as an event occurring at least 2 months after AVF formation and requiring surgical revision or replacement of the fistula. The patients were followed up for a median time of 26 months.

RESULTS

In our group, the mean age was 59.7 ± 13.2 years (median, 62 years), and 60.1% were male. During follow-up, 134 patients (51.9%) maintained AVF patency, whereas 124 (48.1%) lost AVF patency within a mean time of 23.3 ± 28.1 months (median, 10.5 months). We found that age (hazard ratio [HR], 1.015; P = .035) and C-reactive protein (CRP) level (HR, 1.17; P < .0001) were associated with a higher risk of loss of AVF patency. The protective factors for AVF patency were autosomal dominant polycystic kidney disease (HR, 0.336; P = .009), pre-emptive AVF (HR, 0.648; P = .031), and higher level of triglycerides (HR, 0.998; P = .035). In the multivariate adjusted Cox model, CRP level remained an independent predictor for loss of AVF patency (HR, 1.17; 95% confidence interval, 1.1-1.3; P < .0001).

CONCLUSIONS

In our study, CRP level was an independent predictor of AVF patency loss, whereas better AVF survival was independently associated with autosomal dominant polycystic kidney disease and pre-emptive AVF. As a simple noninvasive marker of chronic inflammation, CRP level may be a useful tool to predict AVF outcomes. Further research is needed to assess the protective effects of inflammation reduction on AVF survival.

Immune Dysfunction and Risk of Infection in Chronic Kidney Disease

Cardiovascular disease and infections are directly or indirectly associated with an altered immune response, which leads to a high incidence of morbidity and mortality, and together, they account for up to 70% of all deaths among patients with chronic kidney dysfunction. Impairment of the normal reaction of the innate and adaptive immune systems in chronic kidney disease predisposes patients to an increased risk of infections, virus-associated cancers, and a diminished vaccine response. On the other hand, an abnormal, exaggerated reaction of the immune systems can also occur in this group of patients, resulting in increased production and decreased clearance of proinflammatory cytokines, which can lead to inflammation and its sequelae (eg, atherosclerotic cardiovascular disease). Epigenetically, modifications in hematopoietic stem cells involving a shift from lymphoid to myeloid cell lineage may underlie uremia-associated immunological senescence, which is not reversed by renal replacement therapy, including kidney transplantation. Measures aimed at attenuating the immune abnormalities in chronic kidney disease/end-stage renal disease should be an area of focused research as this could potentially lead to a better understanding and, thus, development of therapies that could reduce the disastrously high death rate in this patient population. The aim of the present article is to review the characteristics, causes, and mechanisms of the immune dysfunction related to chronic kidney disease.

Light wine consumption is associated with a lower odd for cardiovascular disease in chronic kidney disease

AIMS

To examine the association between wine consumption and the prevalence of chronic kidney disease (CKD) and cardiovascular disease (CVD).

DATA SYNTHESIS

We performed a cross-sectional logistic regression analysis of National Health and Nutrition Examination Survey (NHANES) in participants 21 years of age or older from 2003 to 2006 in a large representative study of the U.S.

POPULATION

Wine consumption was categorized as none (0 glass per day), light (<1 glass per day), or moderate (≥1 glasses per day). Prevalent CKD was defined as a urine albumin/creatinine ratio (UACR) ≥30 mg/g or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m². CVD was defined as history of CVD including angina, myocardial infarction, or stroke. Only 27 (0.5%) individuals reported moderate wine consumption, whereas 57.5% and 42% reported abstinence and light wine consumption, respectively. Light wine consumption was associated with a lower prevalence of CKD as opposed to abstinence in unadjusted analysis. After adjusting for demographics and CVD risk factors light wine consumption was associated with lower prevalence of CKD defined as UACR ≥30 mg/g but not with low eGFR. Furthermore, light wine consumption was associated with significantly lower rates of CVD in the general population and in subjects with CKD. The adjusted odd of CVD for those with light wine consumption was 0.72 (CI 0.52-0.99, p = 0.046) for the subjects with CKD.

CONCLUSION

These data suggest that light wine consumption (compared to abstinence) is associated with lower prevalence of CKD and a lower odd of CVD in those with CKD in the U.S.

Associations of sensitive cardiac troponin-I with left ventricular morphology, function and prognosis in end-stage renal disease patients with preserved ejection fraction

Sensitive cardiac troponin I (cTnI) predicts all-cause and cardiovascular mortality in various clinical settings. However, its clinical significance in hemodialysis (HD) patients with preserved left ventricular ejection fraction (LVEF) has not been fully elucidated. This study investigated the association of cTnI with LV morphology and function, and its long-term outcome in HD patients with preserved LVEF. This prospective study consists of 96 HD patients with preserved LVEF (69 ± 8 years and 63% male) who underwent two-dimensional echocardiographic examination and biomarker tests including cTnI, brain natriuretic peptide, and high-sensitive C-reactive protein. The primary endpoint was all-cause death and secondary endpoint was cardiovascular death. Factors independently associated with cTnI were systolic blood pressure (β = - 0.239, p = 0.011), heart rate (β = 0.216, p = 0.021), LV mass index (β = 0.231, p = 0.020), and E to e' ratio (β = 0.237, p = 0.016). During a mean follow-up of 3.6 years, primary and secondary endpoints were observed in 23 (24%) and 18 (19%) patients, respectively. In the multivariate Cox proportional hazard analysis, the upper cTnI tertile has significantly increased risk of all-cause mortality [hazard ratio (HR), 2.69; 95% confidence interval (CI), 1.139-6.386; p = 0.024] and that of cardiovascular death (HR, 4.56; 95% CI 2.021-16.968; p = 0.006) independent of echocardiographic measures and other serum biomarkers. In HD patients with preserved LVEF, serum cTnI levels were significantly associated with diastolic function and risk of mortality independent of echocardiographic variables and other biomarkers.

Malnutrition, inflamation and atherosclerosis (MIA syndrome) in patients with end stage renal disease on maintenance hemodialysis (a single centre experience)

BACKGROUND

Inflammation and malnutrition play an important role in endothelial dysfunction, atherosclerosis and excessive cardiovascular morbidity and mortality in ESRD patients AIM OF THE STUDY: The primary objective is to determine the prevalence of inflammation, malnutrition and atherosclerosis in patients on maintenance haemodialysis. Secondary objective was to determine the association for atherosclerosis with inflammation and malnutrition.

PATIENT AND METHODS

One hundred and one adult patients with end stage renal disease on maintenance haemodialysis who are met with the exclusion criteria were enrolled in this cross sectional study from haemodialysis unit of Baghdad teaching hospital over the period of July/2015 - June 2016. All patients were thoroughly examined and many variables were evaluated (age, gender, blood pressure, diabetes mellitus, serum lipid profile, smoking habits, serum albumin, CRP, calcium, Phosphate, Parathyroid hormone and haemoglobin measurements). All patients underwent a carotid Doppler ultrasound study.

RESULTS

Atherosclerosis was present in 65.3%: 58.4% of patients had malnutrition and 43.6% had inflammation. The association for atherosclerosis and high CRP and low serum albumin is strong and independent of other atherosclerosis risk factors. There is significant inverse and independent correlation between CRP and albumin.

CONCLUSION

Inflammation (high serum CRP) and malnutrition (low serum albumin) in patients on haemodialysis are significantly associated with carotid atherosclerosis. Inflammation was more prevalent in the malnourished patients than in those with normal nutritional status.

Treatment of Dyslipidemia in Chronic Kidney Disease

Dyslipidemia is a common feature of various renal diseases. This perturbed lipid metabolism results in accelerated atherosclerosis and increased cardiovascular morbidity and mortality. Treatment of dyslipidemia, in addition to normalization of blood pressure and reduction of proteinuria, could provide additional means to retard the progression of chronic renal insufficiency. Possible therapeutic approaches include mainly dietary and life-style modifications, selective use of some technical components of dialysis systems, and the judicious prescriptions of lipid-lowering drugs. Even with relatively normal lipid and lipoprotein profiles statin therapy seems to prevent atherogenesis acceleration. A wide range of therapeutic interventions, targeting the lipid abnormalities that may develop in chronic renal patients and end-stage renal disease (ESRD) are currently available, though still without convincing evidence based on long-term prospective studies which clearly demonstrate a significant reduction in cardiovascular morbidity and mortality of ESRD patients. However, extensive investigations, concerning the best long-term therapeutic strategy for this high-risk population of patients, are still missing.

Higher Serum Hepatocyte Growth Factor Concentration is Associated with Better Preservation of GFR in Hemodialysis Patients

BACKGROUND/AIMS

Hemodialysis induces an intravascular inflammatory reaction which may further deteriorate renal function. We studied changes of serum interleukin 6 (IL6) and hepatocyte growth factor (HGF) concentrations during dialysis sessions, and at 12 month intervals. The synthesis of these cytokines in arterial endothelial cells in the presence of serum obtained from dialyzed patients was studied. Changes of the inflammatory reaction during 12 months of treatment were correlated with GFR.

METHODS

The study was performed on a group of 30 uremic patients treated with hemodialysis. Serum samples were collected before the start of dialysis, 15 minutes, and 4 hours later, when the session was finished. Serum levels of IL6 and HGF were measured with ELISA, as was the effect of serum samples on the synthesis of these cytokines in arterial endothelial cells.

RESULTS

At baseline hemodialysis induced an increase of serum IL6 (+10%) and HGF (+164%) levels at the end of the session. After 12 months of treatment predialysis serum IL 6 level was increased as compared to the beginning of the study (+22%), but no change in serum HGF level was observed. At that time the dialysis-induced rise of serum IL6 level was stronger than at the start (+18%), but the observed effect for HGF was weaker (+116%). An inverse correlation was observed between the dialysis-induced increase of HGF level and decrease of GFR after 12 months of study. The same relation was seen for HGF synthesis in the endothelium, but opposite for IL6 synthesis in the endothelium.

CONCLUSIONS

We found that a higher HGF serum level during hemodialysis treatment is associated with a slower loss of residual renal function.