Interleukin-6 predicts hypoalbuminemia, hypocholesterolemia, and mortality in hemodialysis patients

Oxidative stress - chronic kidney disease - cardiovascular disease: A vicious circle

Chronic kidney disease patient's progression to end-stage renal disease as well as their high mortality are linked to cardiovascular disease. However, the high incidence rate of cardiovascular morbidity and mortality in these patients is not fully accounted for by traditional cardiovascular risk factors such as diabetes, hypertension and obesity. Renal disease and CVD are associated with endothelial dysfunction, inflammation and oxidative stress and in this review we will examine what is known regarding their similar roles in both CVD and chronic kidney disease, specifically focusing on the interconnections between oxidative stress, inflammation and endothelial dysfunction. These interconnections are best visualized as a vicious circle wherein these entities coexist and communicate with each other, thereby exacerbating the processes underpinning these different entities with the end result of the high morbidity and mortality that characterize CKD patients. By exploring this vicious circle i.e. the mode and extent of the interrelationships as well as some of the underlying mechanisms involved, this review aims at outlining our current understanding as well as highlighting future avenues for research and potential targets for therapeutic intervention.

The Impact of Uremic Toxins on Cerebrovascular and Cognitive Disorders

Individuals at all stages of chronic kidney disease (CKD) have a higher risk of developing cognitive disorders and dementia. Stroke is also highly prevalent in this population and is associated with a higher risk of neurological deterioration, in-hospital mortality, and poor functional outcomes. Evidence from in vitro studies and in vivo animal experiments suggests that accumulation of uremic toxins may contribute to the pathogenesis of stroke and amplify vascular damage, leading to cognitive disorders and dementia. This review summarizes current evidence on the mechanisms by which uremic toxins may favour the occurrence of cerebrovascular diseases and neurological complications in CKD.

Patients receiving dialysis do not have increased energy needs compared with healthy adults

BACKGROUND

Patients receiving dialysis are thought to have increased energy needs due to stress from the dialysis process or uraemic toxins. However, certain conditions may induce hypometabolic states potentially leading to unwanted weight gains when increased calorie intake is recommended.

OBJECTIVES

Since there is conflicting research, this study aims to assess total energy expenditure (TEE) of patients receiving dialysis through analysis of resting energy expenditure (REE) and physical activity levels.

DESIGN

Comprehensive review of the current literature on REE and physical activity levels.

METHODS

Two electronic databases (PubMed and CINAHL) were searched using keywords to find papers published within the last 10 years for physical activity studies and within the last five years for REE.

INCLUSION CRITERIA

Adults undergoing long-term dialysis treatments who do not have comorbidities that influence energy expenditure such as inflammation, hyperthyroidism or cancers. Participants were also required to ambulate without assistance.

RESULTS

Only seven of the 325 studies found were included in this review. Most studies were controlled trials with one being a prospective study. Patients receiving dialysis had rest energy expenditures comparable to healthy adults. There was not a consensus between studies as to which predictive energy equation produced accurate energy recommendations. Overall, patients receiving dialysis were significantly less active compared with healthy adults and this related to muscle mass.

CONCLUSION

Patients receiving dialysis tend to be sedentary or lightly active and do not have increased energy expenditure compared with healthy adults. Therefore, stable patients should not be prescribed increased calorie intake.

Obesity Paradox in Advanced Kidney Disease: From Bedside to the Bench

While obesity is associated with a variety of complications including diabetes, hypertension, cardiovascular disease and premature death, observational studies have also found that obesity and increasing body mass index (BMI) can be linked with improved survival in certain patient populations, including those with conditions marked by protein-energy wasting and dysmetabolism that ultimately lead to cachexia. The latter observations have been reported in various clinical settings including end-stage renal disease (ESRD) and have been described as the "obesity paradox" or "reverse epidemiology", engendering controversy. While some have attributed the obesity paradox to residual confounding in an effort to "debunk" these observations, recent experimental discoveries provide biologically plausible mechanisms in which higher BMI can be linked to longevity in certain groups of patients. In addition, sophisticated epidemiologic methods that extensively adjusted for confounding have found that the obesity paradox remains robust in ESRD. Furthermore, novel hypotheses suggest that weight loss and cachexia can be linked to adverse outcomes including cardiomyopathy, arrhythmias, sudden death and poor outcomes. Therefore, the survival benefit observed in obese ESRD patients can at least partly be derived from mechanisms that protect against inefficient energy utilization, cachexia and protein-energy wasting. Given that in ESRD patients, treatment of traditional risk factors has failed to alter outcomes, detailed translational studies of the obesity paradox may help identify innovative pathways that can be targeted to improve survival. We have reviewed recent clinical evidence detailing the association of BMI with outcomes in patients with chronic kidney disease, including ESRD, and discuss potential mechanisms underlying the obesity paradox with potential for clinical applicability.

Does inflammation affect outcomes in dialysis patients?

Chronic, low-grade inflammation is a common comorbid condition in chronic kidney disease (CKD), and particularly in chronic dialysis patients. In this review, we consider the question of whether inflammation affects outcomes in dialysis patients. Levels of proinflammatory cytokines, as well as C-reactive protein, are elevated in chronic dialysis patients. Multiple factors likely contribute to chronic inflammatory activation in kidney disease patients including the uremic milieu, lifestyle and epigenetic influences, infectious and thrombotic events, the dialysis process, and dysbiosis. Increased inflammatory markers in both CKD and chronic dialysis patients are associated with adverse clinical outcomes including all-cause mortality, cardiovascular events, kidney disease progression, protein energy wasting and diminished motor function, cognitive impairment, as well as other adverse consequences including CKD-mineral and bone disorder, anemia, and insulin resistance. Strategies that have been shown to reduce chronic systemic inflammation in CKD and chronic dialysis patients include both pharmacological and nonpharmacological interventions. However, despite evidence that systemic inflammatory markers can be lowered in kidney disease patients treated with various strategies, evidence that this improves clinical outcomes is largely unavailable and represents an important future research direction. Overall, there is strong observational evidence that inflammation is high in chronic dialysis patients and that this is independently associated with numerous adverse clinical outcomes. Targeting inflammation represents a potentially novel and attractive strategy if it can indeed improve adverse outcomes common in this population.

Inverse Association Between Serum Non-High-Density Lipoprotein Cholesterol Levels and Mortality in Patients Undergoing Incident Hemodialysis

BACKGROUND

There is accumulating evidence that serum levels of non-high-density lipoprotein cholesterol (non-HDL-C) are a more accurate predictor of cardiovascular outcomes when compared with low-density lipoprotein cholesterol. However, we recently found that higher serum concentrations of triglycerides are associated with better outcomes in patients undergoing hemodialysis. Therefore, we hypothesized that the association of serum levels of non-HDL-C (which includes triglyceride-rich lipoproteins) with outcomes may also be different in patients undergoing hemodialysis when compared with other patient populations.

METHODS AND RESULTS

We studied the association of baseline and time-dependent serum levels of non-HDL-C with all-cause and cardiovascular mortality using Cox proportional hazard regression models in a nationally representative cohort of 50 118 patients undergoing incident hemodialysis from January 1, 2007, to December 31, 2011. In time-dependent models adjusted for case mix and surrogates of malnutrition and inflammation, a graded inverse association between non-HDL-C level and mortality was demonstrated with hazard ratios (95% confidence intervals) of the lowest (<60 mg/dL) and highest (≥160 mg/dL) categories: 1.88 (1.72-2.06) and 0.73 (0.64-0.83) for all-cause mortality and 2.07 (1.78-2.41) and 0.75 (0.60-0.93) for cardiovascular mortality, respectively (reference, 100-115 mg/dL). In analyses using baseline values, non-HDL-C levels <100 mg/dL were also associated with significantly higher mortality risk across all levels of adjustment. Similar associations were found when evaluating non-HDL/HDL cholesterol ratio and mortality, with the highest all-cause and cardiovascular mortality being observed in patients with decreased non-HDL/HDL-C ratio (<2.5).

CONCLUSIONS

Contrary to the general population, decrements in non-HDL-C and non-HDL/HDL cholesterol ratio were paradoxically associated with increased all-cause and cardiovascular mortality in patients undergoing incident hemodialysis. The underlying mechanisms responsible for these associations await further investigation.

Restrictive lung disorder is common in patients with kidney failure and associates with protein-energy wasting, inflammation and cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD), protein-energy wasting (PEW), and inflammation are common interrelated features of chronic kidney disease (CKD). Less is known about lung dysfunction in CKD and its possible role in this context. We evaluated lung function and its association with estimated glomerular filtration rate (GFR), CVD, PEW, and inflammation in individuals with normal to severely reduced GFR.

METHODS

In 404 individuals with GFR category G1 (n = 31; GFR >90mL/min/1.73 m2), G2 (n = 46), G3 (n = 33), G4 (n = 49) and G5 (n = 245; GFR<15mL/min/1.73 m2), pulmonary function was assessed by spirometry. Obstructive (OLD) and restrictive (RLD) lung dysfunction was defined based on forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and peak expiratory flow (PEF), expressed as percentages of predicted values (%FEV1, %FVC and %PEF, respectively). PEW was evaluated by subjective global assessment, handgrip strength (HGS) and lean body mass index (LBMI), and inflammation by interleukin-6 and high sensitivity C-reactive protein.

RESULTS

RLD (defined as FEV1/FVC ≥ 0.70 and %FVC<80) associated with GFR and was present in 36% of G5 and 14% of G1-4 individuals. OLD (FEV1/FVC<0.70) was less common with similar prevalence among G1-4 (9%) and G5 (11%) individuals. Notably, 64% of those with concomitant presence of PEW, inflammation and clinical signs of CVD had RLD while 79% of those lacking these complications had normal lung function. In multivariate logistic regression analysis, RLD associated with CVD, PEW and inflammation, after adjusting for Framingham's CVD risk score, serum albumin, and GFR category.

CONCLUSIONS

RLD is a common complication in patients with advanced CKD, especially in those with concomitant presence of CVD, inflammation and PEW. RLD appears to be an integral albeit scarcely explored consequence of pulmonary-renal interactions in CKD patients.

Design and methods of the REMOVAL-HD study: a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients

BACKGROUND

Removal of uraemic toxins is inadequate using current dialysis strategies. A new class of dialysis membranes have been developed that allow clearance of larger middle molecules. The REMOVAL-HD study (a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients) will address safety, efficacy and the impact on patient-centred outcomes with the use of a mid cut-off (MCO) dialyser in a chronic haemodialysis (HD) population.

METHODS

REMOVAL-HD is an open label, prospective, non-randomised, single-arm, multi-centre device study in 85 chronic HD participants. All visits will be conducted during regular HD sessions and participants will undergo a 1 month wash-in period using a standardised high flux dialyser, 6 months of intervention with a MCO dialyser and 1 month of wash-out using a high flux dialyser. The primary endpoint is change in pre-dialysis concentrations of serum albumin, with secondary endpoints including the efficacy of clearance of free light chains and β-2 microglobulin, and patient-centred outcomes including quality of life, symptom burden, functional status, nutritional status, hospitalisation and death.

DISCUSSION

MCO dialysers are a novel form of HD membrane. The REMOVAL-HD study is a pivotal study designed to monitor the immediate and medium-term effects following exposure to this dialyser.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry Number (ANZCTRN) 12616000804482 . Date of registration - 21/06/2016.

Effects of Omega-3 Fatty Acids on Markers of Inflammation in Patients With Chronic Kidney Disease: A Controversial Issue

Chronic kidney disease (CKD) is a global problem which contributes to a significant morbidity and mortality in China. Concomitant inflammatory state further boosts the mortality due to cardiovascular events in patients with CKD undergoing dialysis. There is a general notion that Omega-3 fatty acids including docosahexaenoic acids (DHA) and eicosapentaenoic (EPA) have certain health benefits perhaps via the regulation of inflammation. However, the anti-inflammatory effect of omega-3 fatty acids in patients with CKD is controversial. We analyzed the data of oral supplementation of omega-3 fatty acids in CKD patients by searching literature on database from inception to August 2016. The analysis included randomized controlled trials (RCTs) derived from multiple databases, and the effect of omega-3 fatty acids supplementation versus the control cohorts were compared. All of the data analysis was calculated by RevMan 5.2. A total of 12 RCTs involving 487 patients were included in the meta-analysis. Among them 254 patients received omega-3 fatty acids and 233 patients served as controls who received placebo. The meta-analysis revealed no statistical significance in serum levels of C-reactive protein (CRP) (SMD, -0.20; 95% CI, -0.44 to 0.05; P = 0.11), IL-6 (SMD, 0.00; 95% CI, -0.33 to 0.33; P = 0.99) and TNF-α (SMD, 0.14; 95% CI, -0.17 to 0.44; P = 0.38) between the omega-3 fatty acids supplementation group and control. This suggested that there is insufficient evidence to conclude the benefit of omega-3 fatty acids oral supplementation in reducing serum levels of CRP, IL-6 and TNF-α in patients with CKD.

Uremic Toxicity: Present State of the Art

The uremic syndrome is a complex mixture of organ dysfunctions, which is attributed to the retention of a myriad of compounds that under normal condition are excreted by the healthy kidneys (uremic toxins). In the area of identification and characterization of uremic toxins and in the knowledge of their pathophysiologic importance, major steps forward have been made during recent years. The present article is a review of several of these steps, especially in the area of information about the compounds that could play a role in the development of cardiovascular complications. It is written by those members of the Uremic Toxins Group, which has been created by the European Society for Artificial Organs (ESAO). Each of the 16 authors has written a state of the art in his/her major area of interest.

Hypoalbuminaemia as a marker of trans-capillary leakage in community-acquired bacteraemia patients

Community-acquired bacteraemia patients (n = 2472), Denmark, 2000-2008. Albumin, C-reactive protein (CRP) and haemoglobin (Hb) measured 2000-2010. We assessed daily mean levels of albumin, CRP and Hb from 30 days before to 30 days after bacteraemia and correlations between albumin vs. CRP and albumin vs. Hb. In linear regression models, we evaluated the contribution of CRP, Hb, chronic and acute variables to the albumin level variations. The mean albumin level (33.6 g/l) was steady before day 1, declined to 29.3 g/l on day 1 with little increase afterward. The mean CRP increased from day -5, peaked on day 1 and declined thereafter. The mean Hb level was fairly constant during days -30/30. Albumin was inversely (R range, - 0.18/-0.47, P < 10-4) correlated with the CRP level and positively (R = 0.17-0.46, P < 10-4) correlated with the HB level. In most models, CRP was the first variable that contributed to the albumin variations, 34-70% of the full model. The sudden decrease of albumin levels, without sudden fluctuations of CRP or Hb, indicated that hypoalbuminaemia was a marker of trans-capillary leakage.

The Relationship between Inflammatory Markers, Leptin and Adiponectin in Chronic Hemodialysis Patients

Chronic inflammation is prevalent in dialysis patients. We investigated the relationship between inflammation and newly identified adipokines: leptin and adiponectin in this population. A total of 129 chronic hemodialysis patients were collected. Serum high sensitivity C-reactive protein (CRP), interleukin-6 (IL-6), leptin and adiponectin levels were determined as well as other metabolic variables. Correlation studies and multiple regression analysis were performed among variables. Our results showed that hemodialysis patients had elevated levels of inflammatory markers, leptin and adiponectin. Diabetic subjects had higher serum CRP and lower albumin levels than non-diabetics. Serum CRP levels were positively correlated with IL-6 levels and negatively correlated with albumin levels. Serum leptin levels were directly related to CRP levels while adiponectin levels were inversely related to CRP levels. A significant negative correlation was observed between serum leptin and adiponectin levels. Serum IL-6 levels were the single independent factor affecting CRP levels. Body mass index can predict both serum leptin and adiponectin levels. We conclude that hemodialysis patients are at an increased risk of chronic inflammation and diabetes patients are even more susceptible to this status. Both serum leptin and adiponectin levels are associated with inflammatory markers. As adipose tissue is the major secreting site of these adipokines, our results suggest that adipose tissue plays an important role in the pathogenesis of chronic inflammation in dialysis patients.

Cardiovascular Risk in Hemodialysis Patients: A Mechanistic Approach

A new formula is proposed to express the excess burden of cardiovascular risk faced by hemodialysis patients as a function of various inherent, acquired and potentially modifiable factors. The proposed equation CVRHD = CVRB X f(([CKD+HD]/[HDtech+Dr])+X) includes the terms: CVRHD (cardiovascular risk in hemodialysis patients); CVRB (baseline cardiovascular risk); CKD (risk associated with chronic kidney disease); HD (risks associated with the process of hemodialysis); HDtech (benefits of new hemodialysis technologies); Dr (benefits of drug therapies) and X (unknown or putative factors influencing cardiovascular morbidity).

We review the various factors included in this proposed formula, touching upon the epidemiology, pathophysiology and therapeutic implications, including possible strategies to modify risk. As is apparent from the formula, CKD and HD in particular act as risk multipliers in augmenting or amplifying the baseline cardiovascular risk, while new hemodialysis technologies may provide an opportunity for “cardioprotective dialysis.” Drug treatment may serve to mitigate some of the risk unique to this population.

Effect of serum inflammatory markers on the prognosis of adult and pediatric patients with Guillain-Barré syndrome

OBJECTIVE

The aim of this study was to evaluate blood neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), C-reactive protein (CRP), and albumin levels for their prognostic value in adult Guillain-Barré syndrome (GBS-A) and pediatric Guillain-Barré syndrome (GBS-P) patients.

PATIENTS AND METHODS

We retrospectively analyzed the medical records of 68 Guillain-Barré syndrome (GBS) patients (36 adults, 32 children) who were treated as inpatients at Harran University Faculty of Medicine, Neurology and Pediatric Neurology Departments. The pretreatment NLR, PLR, CRP, and albumin levels and Hughes scores at hospital admission, discharge, and third-month control were documented.

RESULTS

In GBS-A patients, the mean CRP and NLR levels at admission/discharge and third-month control were significantly higher, and the mean albumin level was significantly lower in the Hughes disability scale (HDS)≥3 group. In GBS-P group, the mean NLR level at third month was significantly higher in the HDS≥3 group. GBS-A patients had higher mean NLR, PLR, and CRP levels and lower mean albumin values than GBS-P patients. Both GBS-A and GBS-P patients had higher mean NLR, PLR, and CRP levels and lower mean albumin values than healthy controls. Only the albumin level of the GBS-A group was found to be a significant predictor of prognosis at discharge from hospital.

CONCLUSION

NLR, CRP, and albumin levels in the GBS-A group and NLR levels in the GBS-P group may be helpful in predicting the prognosis of the disease. The albumin level of GBS-A patients is an independent risk factor for prognosis at discharge from hospital.

Peritoneal dialysis: The unique features by compartmental delivery of renal replacement therapy

Despite decades of research, the clinical efficacy of peritoneal dialysis (PD) remains enigmatic. We may wonder why the modality fail in some patients but perhaps the more proper question would be, why it works in so many? We know that the contribution of residual renal function (RRF), more so than in hemodialysis, is critically important to the well-being of many of the patients. Unique features of the modality include the relatively low volume of dialysate fluid needed to provide effective uremic control and the disproportionate tendency for both hypokalemia and hypoalbuminemia, when compared to hemodialysis. It is currently believed that most uremic toxins are generated on the interface of human and bacterial structures in the gastrointestinal tract, the intestinal biota. PD offers disproportionate removal of these toxins upon "first-pass", i.e., via PD fluid exchanges before reaching the systemic circulation beyond the gastrointestinal compartment. Studies examining the net removal gradient of protein-bound uremic toxins during PD are scarce, whereas RRF receives considerably more attention without effective interventions being developed to preserve it. We propose an alternative view on PD, emphasizing the modality's compartmental nature, both for its benefits and the limitations.

Periodontitis and early mortality among adults treated with hemodialysis: a multinational propensity-matched cohort study

BACKGROUND

Periodontitis is associated with cardiovascular mortality in the general population and adults with chronic diseases. However, it is unclear whether periodontitis predicts survival in the setting of kidney failure.

METHODS

ORAL-D was a propensity matched analysis in 3338 dentate adults with end-stage kidney disease treated in a hemodialysis network in Europe and South America designed to examine the association between periodontitis and all-cause and cardiovascular-related mortality in people on long-term hemodialysis. Participants were matched 1:1 on their propensity score for moderate to severe periodontitis assessed using the World Health Organization Community Periodontal Index. A random-effects Cox proportional hazards model was fitted with shared frailty to account for clustering of mortality risk within countries.

RESULTS

Among the 3338 dentate participants, 1355 (40.6%) had moderate to severe periodontitis at baseline. After using propensity score methods to generate a matched cohort of participants with periodontitis similar to those with none or mild periodontal disease, moderate to severe periodontitis was associated with a lower risk of all-cause (9.1 versus 13.0 per 100 person years, hazard ratio 0.74, 95% confidence interval 0.61 to 0.90) and cardiovascular (4.3 versus 6.9 per 100 person years, hazard ratio 0.67, 0.51 to 0.88) mortality. These associations were not changed substantially when participants were limited to those with 12 or more natural teeth and when accounting for competing causes of cardiovascular death.

CONCLUSION

In contrast to the general population, periodontitis does not appear to be associated with an increased risk of early death in adults treated with hemodialysis.

Association of inflammatory cytokines with mortality in peritoneal dialysis patients

Aims: Previous study on association between pro-inflammatory cytokines and mortality in PD population is limited. We aimed to investigate here.

Methods: Total 50 patients who underwent incident PD were enrolled in this study. We measured the titers of pro-inflammatory cytokines Interleukin-18(IL-18), Interleukin-6 (IL-6), and Interleukin-1ß (IL-1ß). Study outcomes were all-cause mortality, cardiovascular-related mortality, and infection-caused mortality. Cox-regression model was used.

Results: In this 7 year prospective study, IL-18 ≥ 804.3pg/ml, IL-6 ≥ 3.92 pg/ml, IL-1ß ≥ 0.86pg/ml, age ≥ 50 years-old, and existence of diabetes could be used as individual significant predictors for mortality in PD patients. Higher titers of IL-6 were associated with lower averaging albumin levels within 1^st year of PD. Increasing numbers of these risk markers of mortality was associated with decreasing survival advantages (P = 0.001).

Conclusion: Age ≥ 50 years-old, diabetes, and inflammatory cytokines profiles at the start of PD therapy could predict for 7-year mortality in PD population.

Pathophysiology of the cardio-renal syndromes types 1-5: An uptodate

According to the recent definition proposed by the Consensus conference on Acute Dialysis Quality Initiative Group, the term cardio-renal syndrome (CRS) has been used to define different clinical conditions in which heart and kidney dysfunction overlap. Type 1 CRS (acute cardio- renal syndrome) is characterized by acute worsening of cardiac function leading to AKI (5, 6) in the setting of active cardiac disease such as ADHF, while type - 2 CRS occurs in a setting of chronic heart disease. Type 3 CRS is closely link to acute kidney injury (AKI), while type 4 represent cardiovascular involvement in chronic kidney disese (CKD) patients. Type 5 CRS represent cardiac and renal involvement in several diseases such as sepsis, hepato - renal syndrome and immune - mediated diseases.

Acute-Phase Proteins and Iron Status in Cats with Chronic Kidney Disease

Background

The role of inflammation in the development and progression of chronic kidney disease (CKD) in cats is not well characterized. Hepcidin is a recently discovered acute‐phase protein (APP) that plays an important role in iron metabolism and contributes to the development of anemia in humans with CKD.

Objectives

To compare serum APP concentrations, iron status, and erythropoietin (EPO) concentrations in healthy cats and cats with naturally occurring CKD.

Animals

A total of 18 healthy control cats and 38 cats with CKD.

Methods

Prospective study. After complete physical examination and routine blood analysis, the following tests were performed: serum amyloid A (SAA), haptoglobin (HAP), EPO, serum iron and ferritin concentration as well as total iron‐binding capacity (TIBC). Serum hepcidin‐25 concentration was measured by ELISA kit designed for use in humans.

Results

Mean SAA and hepcidin concentrations were significantly higher and mean total iron and TIBC were significantly lower in the CKD group (P < .05). There was a significant positive correlation between serum creatinine concentration (CRT) and 2 of the APPs (SAA and hepcidin; P < .05). Increases in SAA and hepcidin were associated with decreases in TIBC and hematocrit in the CKD group. Fourteen (37%) of the cats with CKD were anemic, and these cats had significantly lower TIBC (P < .05), suggesting a functional iron deficiency. There was no association between survival time and APP, iron status, or EPO concentrations.

Conclusions

Our data suggest that CKD in cats is associated with systemic inflammation and altered iron metabolism. With further validation in cats, hepcidin assays may help better characterize these relationships.

The Resection of Thyroid Cancer Was Associated with the Resolution of Hyporesponsiveness to an Erythropoiesis-stimulating Agent in a Hemodialysis Patient with Aceruloplasminemia

We herein report the case of a hemodialysis patient whose response to an erythropoiesis-stimulating agent (ESA) improved following the resection of thyroid cancer. Her hemoglobin level remained below 7 g/dL, despite the use of ESA. During the search for the causes of her hyporesponsiveness to ESA, papillary thyroid cancer and aceruloplasminemia were found. The existence of other potential causes, such as iron deficiency, infectious disease, severe hyperparathyroidism and malnutrition were ruled out. Following the resection of the thyroid cancer tumor, her hemoglobin level increased to 10.2 g/dL over a period of 4 months. This is the first report to demonstrate the resolution of hyporesponsiveness to ESA following the resection of a malignant tumor.

Malnutrition Inflammation Score cut-off predicting mortality in maintenance hemodialysis patients

BACKGROUND

Malnutrition is a strong predictor of mortality on hemodialysis patients, especially when it is associated with inflammation. Malnutrition Inflammation Score (MIS) is a simple and low cost tool which assesses the presence of malnutrition associated with inflammation. Therefore, the aim is to evaluate if MIS is associated with mortality in patients on maintenance hemodialysis and establish a cut-off to predict mortality at different follow-up periods.

METHODS

Observational retrospective cohort study including 215 patients on hemodialysis between July 2012 and June 2014, censored until November 2015. MIS was used to assess patient's nutritional status at the moment they were enrolled in the study. They were followed for at least 18 months.

RESULTS

At the end of 18 months, 38 (17.7%) deaths, 20 renal transplants (9.3%), four facilities transference (1.9%), three dialysis method change (1.4%) and one renal function recovery (0.5%) were observed. One hundred seventy one patients completed at least 24 months of follow-up, and during this additional period, there were five deaths and one renal transplant more. Score higher than 7 points was able to predict mortality for both follow-up periods using sensitivity and specificity analysis and ROC curves. Using this cut-off on Kaplan-Meier survival curve, it was possible to confirm the association of MIS with all-cause mortality at 18 months and 24 or more months of follow-up. Finally, Cox multivariate analysis adjusted for demographic, clinical and nutritional variables showed MIS as the only significant predictor of mortality.

CONCLUSION

MIS is an independent predictor of mortality in hemodialysis patients.

Change in serum albumin concentration is inversely and independently associated with risk of incident metabolic syndrome

BACKGROUND

Low serum albumin concentration is associated with a high risk of morbidity and mortality from cardiovascular diseases. However, high serum albumin level appears to be linked to metabolic syndrome (MetS). This study aimed to dissect the relative contributions of baseline and change in serum albumin concentration to the risk of incident metabolic syndrome.

METHODS

This was a 5-year (63,060 person-years) retrospective longitudinal study of 12,567 participants without metabolic syndrome, diabetes, or cardiovascular disease who were enrolled in a health screening program. The risk of developing MetS was analyzed according to baseline and change in serum albumin concentration.

RESULTS

A total of 2582 incident cases of metabolic syndrome developed. The hazard ratio (HR) for incident MetS increased with increasing quartile of baseline serum albumin level compared with those in the lowest quartile, in a fully adjusted model (p for trend = 0.013). The HRs [95% confidence intervals (CIs)] of incident MetS comparing the second, third, and fourth quartiles to the first quartile of change in serum albumin level were 0.478 (0.421-0.544), 0.353 (0.307-0.405), and 0.262 (0.224-0.305) in the fully adjusted model, respectively (p for trend <0.001). Percent change in serum albumin concentration inversely correlated with percent change in serum level of high-sensitivity C-reactive protein (r=-3.5444, p<0.001).

CONCLUSIONS

Although a higher baseline level of serum albumin was linked to increased risk of incident metabolic syndrome, increase in serum albumin concentration might be a protective factor against the risk of MetS.

Analysis of the kinetics of the parathyroid hormone, and of associated patient outcomes, in a cohort of haemodialysis patients

Background

Observational studies have recently associated a decrease in serum parathyroid hormone (PTH) level with a higher rate of mortality among hemodialysis (HD) patients. Decreases in PTH level can result from medical intervention (MPD) and surgical parathyroidectomy (PTX), or may occur spontaneously, usually associated with an underlying malnutrition-inflammation syndrome (SPD). The aim of our study was to prospectively identify the incidence of decreases in PTH level in a cohort of HD patients and the frequency distribution of the different causes (MPD, PTX and SPD), as well as to evaluate the survival outcomes for each PTH group (MPD, PTX and SPD) compared to patients who did not experience a PTH decrease over the first 36 months of the study (NPD).

Methods

The 197 patients receiving HD at our center in January 2010, and meeting our eligibility criteria, were enrolled in our prospective study, and were observed for a period of 60 months. A decrease in PTH level >50 % between two successive PTH measurements obtained within an interval <3 months was defined as a significant event. MPD referred to a decrease in PTH due to an increased oral calcium intake, increased dialysate calcium concentration (DCC), increased alfacalcidol use, or use of cinacalcet therapy. A surgical 7/8 PTX was performed in young patients or in patients in whom cinacalcet therapy failed. SPD referred to a decrease in PTH related to a medical or surgical event. Baseline characteristics among patients in each group (MPD, PTX, SPD, and NPD) were evaluated using Fisher’s exact test. The 60-month survival was evaluated using Kaplan-Meier and Cox multivariable proportional hazards models. Univariate and multivariate Cox analyzes were used identify variables with mortality. The relative risk of mortality was expressed as a hazard ratio (HR).

Results

The distribution of the 197 patients forming our four study groups was 34 % in the NPD group, 35 % in the SPD group, 25 % in the MSD group and 6 % in the PTX group. Among patients in the SPD group, the main acute comorbid conditions were peripheral vascular and cardiac complications, sepsis, fractures, and cancers with an increase in serum CRP level (from 14.3 ± 18 to 132 ± 90 mg/L) and a decrease in serum albumin (from 33 ± 4.5 to 28.6 ± 4 g/L). In the MPD group, the main therapeutic change was an increase in DCC, either independently or in association with cinacalcet therapy. The median survival rate among patients was 10 months for SPD, compared to 22 months among patients in the MPD group (p < 0.001). Using multivariable Cox model and taking the NPD group as reference, the risk of mortality was lower among patients in the MPD group (HR, 0.42[0.2-0.87] p = 0.01), with survival being comparable for the SPD and NPD groups (HR, 1.3 [0.75-2.2]). No mortality was observed in the PTX group.

Conclusion

The poor outcomes associated with SPD, related to acute comorbid conditions, should not lead to undertreat secondary hyperparathyroidism whose appropriate medical or surgical therapies are associated with better outcomes.

Psoriatic inflammation causes hepatic inflammation with concomitant dysregulation in hepatic metabolism via IL-17A/IL-17 receptor signaling in a murine model

Psoriatic inflammation has been shown to be associated with cardiovascular dysfunction and systemic inflammation. Recently, psoriasis has also been linked to hepatic disorders, however underlying mechanism connecting the two are unknown. IL-17A being a central pro-inflammatory cytokine in the pathogenesis of psoriasis may be involved in hepatic inflammation through its receptor and downward signaling; however so far no study has investigated IL-17A related signaling in the liver during psoriasis in a murine model. Therefore, this study explored psoriasis-induced hepatic inflammation and concurrent metabolic changes. Mice were applied topically imiquimod (IMQ) to develop psoriatic inflammation. Additionally mice were also treated either with IL-17A or anti-IL17A antibody to explore the role of IL-17 related signaling in liver. Mice were then assessed for hepatic inflammation through assessment of inflammatory/oxidative stress markers (IL-17RC, NFκB, IL-6, MCP-1, IL-1β, GM-CSF, ICAM-1, iNOS, lipid peroxides and myeloperoxidase activity) as well as hepatic injury (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) and protein/lipid metabolic biomarkers (total proteins, albumin, total bilirubin, triglycerides, HDL cholesterol, and total cholesterol). IMQ treatment led to hepatic inflammation as evidenced by increased pro-inflammatory cytokines and oxidative stress with concomitant dysregulation in hepatic protein/lipid metabolism. Treatment with IL-17A further aggravated, whereas treatment with anti-IL17A antibody ameliorated IMQ-induced changes in hepatic injury/inflammation and protein/lipid metabolism. Our study shows for the first time that psoriatic inflammation leads to hepatic inflammation which results in dysregulated protein/lipid metabolism through IL-17RC/NFκB signaling. This could result in increased risk of cardiovascular dysfunction in patients with psoriasis.

Tumor necrosis factor α is a risk factor for infection in peritoneal dialysis patients

BACKGROUND/AIMS

It has been shown that circulating tumor necrosis factor α (TNF-α) is elevated in end stage renal disease patients; however, the relationship between TNF-α and the development of infection in these patients is unknown. In this study, we investigated the association of plasma TNF-α and interleukin 6 (IL-6) with infection in peritoneal dialysis (PD) patients. We also evaluated the association of their plasma levels with the production by peripheral blood mononuclear cells (PBMC), and with various clinical parameters.

METHODS

We enrolled 32 patients on maintenance PD and 10 healthy controls. Plasma and PBMC were isolated from blood. PBMC were stimulated with lipopolysaccharide in vitro.

RESULTS

Mean follow-up duration was 775 days. Six patients developed organ infections (five pneumonia and one liver abscess), and six patients developed PD peritonitis and eight developed exit site infection. Plasma TNF-α and IL-6 levels were significantly elevated in organ infections but not in peritonitis or in exit site infection. Plasma TNF-α was the only significant risk factor for organ infections and pneumonia in multivariate regression analysis. Patients with high plasma TNF-α levels showed a significantly greater cumulative hazard rate for organ infections compared to those with low TNF-α levels. Plasma TNF-α levels correlated with TNF-α production by PBMC and showed an inverse association with Kt/V.

CONCLUSIONS

This is the first study showing that plasma TNF-α is a significant risk factor for infection in PD patients.

Comparison and relationship of thyroid hormones, IL-6, IL-10 and albumin as mortality predictors in case-mix critically ill patients

OBJECTIVE

To compare the ability of thyroid hormones, IL-6, IL-10, and albumin to predict mortality, and to assess their relationship in case-mix acute critically ill patients.

METHODS

APACHE II scores and serum thyroid hormones (FT3, FT4, and TSH), IL-6, IL-10, and albumin were obtained at EICU admission for 79 cases of mix acute critically ill patients without previous history of thyroid disease. Patients were followed for 28 days with patient's death as the primary outcome. All mean values were compared, correlations assessed with Pearson' test, and mortality prediction assessed by multivariate logistic regression and ROC.

RESULTS

Non survivors were older, with higher APACHE II score (p=0.000), IL-6 (p<0.05), IL-10 (p=0.000) levels, and lower albumin (p=0.000) levels compared to survivors at 28 days. IL-6 and IL-10 had significant negative correlation with albumin (p=0.001) and FT3 (p ⩽ 0.05) respectively, while low albumin had a direct correlation with FT3 (p<0.05). In the mortality prediction assessment, IL-10, albumin and APACHE II were independent morality predictors and showed to have a good (0.70-0.79) AUC-ROC (p<0.05). Despite that the entire cohort showed low FT3 serum levels (p=0.000), there was not statistical difference between survivors and non-survivors; neither showed any significance as mortality predictor.

CONCLUSIONS

IL-6 and IL-10 are correlated with Low FT3 and hypoalbuminemia. Thyroid hormones assessed at EICU admission did not have any predictive value in our study. And finally, high levels of IL-6 and IL-10 in conjunction with albumin could improve our ability to evaluate disease's severity and predict mortality in the critically ill patients. When use in combination with APACHE II scores, our model showed improved mortality prediction.

Salivary levels of interleukin-6 and tumor necrosis factor-α in patients undergoing hemodialysis

Background:

Inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) are elevated in end-stage renal disease (ESRD). IL-6 and TNF-α are toxins which deteriorate renal function, and their pathogenic role has been confirmed in cardiovascular and oral diseases. This study was designed to investigate the salivary levels of IL-6 and TNF-α in patients with ESRD undergoing hemodialysis (HD).

Materials and Methods:

Twenty patients with ESRD who were treated with 4 h HD sessions, with low flux membrane were included in this cross-sectional study. Average Kt/V index in patients was 1.19 ± 0.1. Twenty age-sex-matched healthy controls with no infectious diseases during 1 month before saliva sampling were selected. Unstimulated whole saliva was collected and TNF-α and IL-6, concentrations were measured using human IL-6 and TNF-α ELISA kits. Independent t-test was used to analyze the data using SPSS (α = 0.05).

Results:

There was a significant difference between dialysis and control groups regarding the salivary levels of TNF-α (P = 0.034) and IL-6 (P = 0.001).

Conclusion:

Considering the results of this study and reported role of inflammatory cytokines in the pathogenesis of cardiovascular and oral diseases, measurement of salivary IL-6 and TNF-α in HD patients may help in risk stratification of HD patients and in planning pertinent preventive strategies.

Understanding cachexia as a cancer metabolism syndrome

Metabolic reprogramming occurs in tumors to foster cancer cell proliferation, survival and metastasis, but as well at a systemic level affecting the whole organism, eventually leading to cancer cachexia. Indeed, as cancer cells rely on external sources of nitrogen and carbon skeleton to grow, systemic metabolic deregulation promoting tissue wasting and metabolites mobilization ultimately supports tumor growth. Cachectic patients experience a wide range of symptoms affecting several organ functions such as muscle, liver, brain, immune system and heart, collectively decreasing patients' quality of life and worsening their prognosis. Moreover, cachexia is estimated to be the direct cause of at least 20% of cancer deaths. The main aspect of cachexia syndrome is the unstoppable skeletal muscle and fat storage wasting, even with an adequate caloric intake, resulting in nutrient mobilization – both directly as lipid and amino acids and indirectly as glucose derived from the exploitation of liver gluconeogenesis – that reaches the tumor through the bloodstream. From a metabolic standpoint, cachectic host develops a wide range of dysfunctions, from increased insulin and IGF-1 resistance to induction of mitochondrial uncoupling proteins and fat tissue browning resulting in an increased energy expenditure and heat generation, even at rest. For a long time, cachexia has been merely considered an epiphenomenon of end-stage tumors. However, in specific tumor types, such as pancreatic cancers, it is now clear that patients present markers of tissue wasting at a stage in which tumor is not yet clinically detectable, and that host amino acid supply is required for tumor growth. Indeed, tumor cells actively promote tissue wasting by secreting specific factors such as parathyroid hormone-related protein and micro RNAs. Understanding the molecular and metabolic mediators of cachexia will not only advance therapeutic approaches against cancer, but also improve patients' quality of life.

Lipoprotein(a) is a risk factor for aortic and mitral valvular stenosis in peripheral arterial disease

AIMS

Lipoprotein(a) (Lp(a)) levels have been associated with aortic valvular calcification and stenosis. The prevalence and risk factors, including Lp(a) level, for valvular heart disease (VHD) were investigated in patients with peripheral arterial disease (PAD).

METHODS AND RESULTS

Echocardiography was performed in 861 patients with PAD to detect abnormal cardiac findings. Relationships between VHD and risk factors were analysed. The prevalence of VHD was 43.6%, and the prevalences of aortic valve regurgitation (AR), mitral valve regurgitation (MR), aortic valve stenosis (AS), mitral valve stenosis (MS), and tricuspid regurgitation (TR) were 26.8, 19.7, 5.9, 1.3, and 9.4%, respectively. In stepwise multiple regression analysis, severity of AR was related to age, albumin, and estimated glomerular filtration rate (eGFR); MR was related to eGFR and age; AS was related to eGFR, Lp(a), and age; MS was related to Lp(a) and female gender; and TR was related to age, body mass index, and total cholesterol (all P < 0.05). Lp(a) level was higher in patients with AS compared with those without AS [34.0 (16.7-50.0) vs. 20.0 (11.0-35.0) mg/dL, P = 0.002], in patients with MS compared with those without MS [37.0 (21.5-77.3) vs. 21.0 (11.0-35.0), P = 0.037], and in patients with AS and/or MS compared with those without AS and MS [34.0 (17.3-50.0) vs. 20.0 (11.0-35.0), P = 0.001]. Lp(a) levels were related to low-density lipoprotein cholesterol and high-sensitivity C-reactive protein levels (P = 0.004).

CONCLUSIONS

The high prevalence of VHD is found, especially in AR and MR, and the Lp(a) level is associated with increased risks of AS and MS in patients with PAD.

Patterns of oral disease in adults with chronic kidney disease treated with hemodialysis

BACKGROUND

Oral disease is a potentially treatable determinant of mortality and quality of life. No comprehensive multinational study to quantify oral disease burden and to identify candidate preventative strategies has been performed in the dialysis setting.

METHODS

The ORAL disease in hemoDialysis (ORALD) study was a prospective study in adults treated with hemodialysis in Europe (France, Hungary, Italy, Poland, Portugal and Spain) and Argentina. Oral disease was assessed using standardized WHO methods. Participants self-reported oral health practices and symptoms. Sociodemographic and clinical factors associated with oral diseases were determined and assessed within nation states.

RESULTS

Of 4726 eligible adults, 4205 (88.9%) participated. Overall, 20.6% were edentulous [95% confidence interval (CI), 19.4-21.8]. Participants had on average 22 (95% CI 21.7-22.2) decayed, missing or filled teeth, while moderate to severe periodontitis affected 40.6% (95% CI 38.9-42.3). Oral disease patterns varied markedly across countries, independent of participant demographics, comorbidity and health practices. Participants in Spain, Poland, Italy and Hungary had the highest mean adjusted odds of edentulousness (2.31, 1.90, 1.90 and 1.54, respectively), while those in Poland, Hungary, Spain and Argentina had the highest odds of ≥14 decayed, missing or filled teeth (23.2, 12.5, 8.14 and 5.23, respectively). Compared with Argentina, adjusted odds ratios for periodontitis were 58.8, 58.3, 27.7, 12.1 and 6.30 for Portugal, Italy, Hungary, France and Poland, respectively. National levels of tobacco consumption, diabetes and child poverty were associated with edentulousness within countries.

CONCLUSIONS

Oral disease in adults on hemodialysis is very common, frequently severe and highly variable among countries, with much of the variability unexplained by participant characteristics or healthcare. Given the national variation and high burden of disease, strategies to improve oral health in hemodialysis patients will require implementation at a country level rather than at the level of individuals.

Risk of Early Mortality in Patients With Newly Diagnosed Multiple Myeloma

The overall survival of patients with multiple myeloma (MM) has been improved greatly over the last 2 decades with the broader use of novel drugs and autologous tandem transplantation. However, more than one tenth of myeloma patients still die shortly after diagnosis. We therefore aim to investigate the risk factors of early mortality (death within 60 days after diagnosis) in patients with MM. We included in this study 451 consecutive patients with MM, newly diagnosed at an Asian tertiary medical center between January 1, 2002 and April 30, 2015. A total of 57 subjects who experienced early mortality were identified. Risk factors for early mortality in myeloma patients were collected and analyzed. Early mortality occurred in 57 (12.6%) of the myeloma patients. In the multivariate analysis, being male (adjusted OR 2.93, 95% CI 1.17-7.31), serum albumin < 3.5  g/dL (adjusted OR 2.71, 95% CI 1.09-6.74), primary plasma cell leukemia (adjusted OR 17.61, 95% CI 1.01-306.05), serum albumin (adjusted OR 2.70, 95% CI 1.15-6.38), corrected serum calcium ≥ 12  mg/dL (adjusted OR 2.94, 95% CI 1.21-7.14), and LDH ≥ 250  U/L (adjusted OR 3.07, 95% CI 1.50-6.27) were identified as independent risk factors of early mortality. Pneumonia with other infections contributed most to early mortality (n = 36, 65%), followed by renal failure and cardiac failure. The early mortality rate is high (12.6%) in patients with MM. Patients who are male and those with primary plasma cell leukemia, low serum albumin, high-corrected serum calcium, or LDH are at risk of early mortality. Nearly two thirds of the myeloma patients who experienced early mortality in our study (37 of 57, 65%) died of infection. Once a high-risk group is identified, much effort is required to target new approaches for prevention, early detection, and treatment of infections.

Correlation of Inflammation and Lipoprotein (a) with Hypercoagulability in Hemodialysis Patients

Background:

Inflammatory and procoagulant markers are potential mediators for the cardiovascular risk in hemodialysis patients. Lipoprotein (a) [Lp(a)], is another important risk factor with inflammatory and procoagulant effects.

Materials and methods:

In 78 hemodialysis patients and 40 controls, C-reactive protein (CRP), Interleukin-6 (IL-6), lipoprotein (a) [Lp (a)], fibrinogen, D-dimer, von Wilebrand factor (vWF) and serum albumin were determined.

Results:

CRP, IL-6, Lp(a), fibrinogen, D-dimer and vWF, were significantly higher, and serum albumin was significantly lower in patients compared to controls (24.40 mg/L vs. 6.39 mg/L, p<0.001; 1.92 pg/ml vs. 0.35 pg/ml, 28.05 mg/dL vs.16.25 mg/dL, p<0.001; 3.44 g/L vs. 2.55 g/L, p<0.01; 1.81 µgFEU /ml vs. 0.50 µgFEU /ml, p<0.01; 152.9 % vs. 85.6 %, p<0.001; 32.1 g/L vs. 40.50 g/L, p<0.001). The patients were divided into two groups: 40 patients with CRP levels over than 10 mg/L and 38 with CRP levels in normal range. These parameters showed significant differences between patients with elevated CRP and patients with normal CRP levels. CRP and IL-6 correlated positively with Lp(a), (r = 0.62, p < 0.001; r=0.54, p<0.001), fibrinogen, (r = 0.63, p < 0.001; r = 0.49, p<0.01) D dimer (r = 0.72, p<0.001; r = 0.55, p<0.01), vWF (r = 0.76, p<0.01; r = 0.63, p<0.001) and negatively with serum albumin (r = -0.80, p<0.01; r = -0.60, p<0.001), in patients with elevated CRP, but not in patients with normal CRP levels and controls.

Conclusion:

According to the results hemodialysis patients with increased inflammatory markers, have the elevated Lp(a) and procoagulant markers and the greater risk for atherosclerotic cardiovascular disease.

Warfarin use and the risks of stroke and bleeding in hemodialysis patients with atrial fibrillation: A systematic review and a meta-analysis

BACKGROUND AND AIM

The efficacy and safety of warfarin therapy in hemodialysis (HD) patients with atrial fibrillation (AF) remains controversial. Thus, we performed, up to date, the first meta-analysis on the risks of stroke and bleeding in warfarin treatment in these populations.

METHODS AND RESULTS

The relevant literature was searched using the following electronic databases without any language restrictions: the Cochrane Library Database, PubMed, ISI, Ovid, and Chinese Biomedical Database from the establishment of the database to October 2014. The studies were included if (a) studies described the risk of stroke or bleeding with or without warfarin in dialysis patients with AF, (b) studies provided information about hazard ratio (HR) and 95% confidence interval (CI) of stroke or bleeding, and (c) the study design was a clinical cohort. The inverse variance method was used to obtain overall HRs and 95% CIs. Sensitivity analyses and publication bias were also performed. We identified six eligible studies with a total of 9816 patients. Combined HRs showed that warfarin cannot prevent strokes in HD patients with AF (HR = 1.23, 95% CI 0.80-1.87; P = 0.347), but its use was associated with a higher risk of bleeding (HR = 1.20, 95% CI 1.03-1.39; P = 0.019).

CONCLUSION

This meta-analysis suggested that warfarin should not be recommended for the routine treatment of HD patients with AF.

An intradialytic increase in serum interleukin-6 levels is associated with an increased mortality in hemodialysis patients

BACKGROUND

The inflammatory marker interleukin-6 (IL-6) increases early in the inflammatory cascade. The aim of this study was to evaluate whether an increase in serum IL-6 levels during a hemodialysis (HD) session is associated with mortality.

METHODS

57 adult patients treated with HD for more than 1 month were prospectively studied over a 3-year follow-up period. Demographic and clinical data were collected and blood samples were drawn before and after a midweek HD session. Events of death and censoring were recorded.

RESULTS

During the 3-year follow-up, 50.8% of the patients died. In univariate Cox regression analysis, an increase in IL-6 levels during HD was associated with an increased mortality (HR 1.41 per pg/ml; 95% CI 1.06 to 1.88; P = .017). In multivariate Cox models, the only independent predictors of all-cause mortality were: an increase in IL-6 levels during dialysis (HR 1.46 per pg/ml; 95% CI 1.08 to 1.98; P = .014), higher baseline C-reactive protein (CRP) levels and older age. When predictors of an increase in serum IL-6 levels during HD were introduced into the model, mortality was still significantly associated with IL-6 elevation during dialysis (HR 1.47 per pg/ml, 95% CI 1.01 to 2.14; P = .045).

CONCLUSIONS

A rise in serum IL-6 levels during a single HD session is associated with a higher mortality among HD patients, independent of predialysis CRP or IL-6 levels. The results may imply the presence of an intradialytic inflammatory response that affects survival in HD patients.

Intradialytic protein supplementation reduces inflammation and improves physical function in maintenance hemodialysis patients

OBJECTIVE

Protein malnutrition is both a cause and consequence of inflammation and related comorbidities for maintenance hemodialysis (MHD) patients. This study sought to determine if oral supplementation with soy or whey protein during dialysis treatment reduces inflammation and improves physical function and body composition in MHD patients.

DESIGN

The design used in the study was randomized controlled trial, and the setting used was hemodialysis clinics in Champaign and Chicago, Illinois.

SUBJECTS

Patients who received treatment ≥3 days/week, were ages ≥30 years did not have congestive heart failure or chronic obstructive pulmonary disease, and were receiving dialysis treatment for ≥3 months were eligible for inclusion.

INTERVENTION

Patients were randomized to oral supplementation with a whey protein, soy protein, or placebo beverage. Patients (WHEY, n = 11; SOY, n = 12; CON, n = 15) consumed their assigned beverage before every dialysis session for 6 months.

MAIN OUTCOME MEASURES

Body composition was measured by dual-energy x-ray absorptiometry, physical function by gait speed and shuttle walk test, and markers of inflammation (C-reactive protein and interleukin 6) using commercially available enzyme-linked immunosorbent assay kits before and after the 6-month intervention. Dietary intake was assessed by 24-hour dietary recalls.

RESULTS

Six months of whey or soy supplementation significantly reduced predialysis interleukin 6 levels (P < .05 for both), whereas there was a trend for a reduction in C-reactive protein when both protein groups were combined (P = .062). Gait speed and shuttle walk test performance also significantly improved in the protein groups (P < .05 for both). No changes in body composition were observed. However, alkaline phosphatase, a marker of bone turnover, was significantly reduced in the protein groups.

CONCLUSIONS

Intradialytic protein supplementation during a 6-month intervention reduced inflammation and improved physical function and represents an affordable intervention to improve the health of MHD patients.

Indoxyl sulfate induces IL-6 expression in vascular endothelial and smooth muscle cells through OAT3-mediated uptake and activation of AhR/NF-κB pathway

BACKGROUND/AIMS

Interleukin-6 (IL-6) is one of the inflammation biomarkers with highest predictive value for outcome in chronic kidney disease (CKD) patients. The present study aimed to determine the effects of indoxyl sulfate (IS) on IL-6 expression in vascular cells.

METHODS

IS was administered to normo- and hypertensive rats. Human umbilical vein endothelial cells (HUVECs) and human aortic smooth muscle cells (HASMCs) were incubated with or without IS.

RESULTS

Immunohistochemistry revealed that IS-administered rats showed increased expression of IL-6 in the aortic tissues. IS increased IL-6 expression in HUVECs and HASMCs in a time- and dose-dependent manner. Knockdown of organic anion transporter 3 (OAT3) using small interfering RNA (siRNA) inhibited IS-induced expression of IL-6 in HUVECs and HASMCs. IS induced activation of aryl hydrocarbon receptor (AhR) and nuclear factor-κB (NF-κB) subunit p65 in HUVECs and HASMCs. Both AhR siRNA and p65 siRNA inhibited IS-induced expression of IL-6. AhR siRNA inhibited IS-induced phosphorylation and nuclear translocation of p65 without change in total p65 level. However, p65 siRNA did not inhibit IS-induced nuclear translocation of AhR. Thus, AhR is responsible for IS-induced p65 signaling transduction.

CONCLUSION

IS induces IL-6 expression in vascular endothelial and smooth muscle cells through OAT3/AhR/NF-κB pathway.

Therapeutic C3 inhibitor Cp40 abrogates complement activation induced by modern hemodialysis filters

Approximately 350,000 individuals in the United States rely on maintenance hemodialysis treatment because of end-stage renal disease. Despite improvements in dialysis technology, the mortality rate for patients treated with maintenance dialysis is still exceptionally high, with a 5-year survival rate of only 35%. Many patients succumb to conditions resulting at least in part from the chronic induction of inflammation. Among the triggers of inflammation, the complement system is of particular importance, being a well-appreciated mediator of inflammatory processes that is involved in many pathologic states. Here we used a refined pre-clinical model of hemodialysis in cynomolgus monkeys to confirm that even modern, polymer-based hemodialysis filters activate complement and to evaluate the potential of Cp40, a peptidic C3 inhibitor, to attenuate hemodialysis-induced complement activation. Our data show marked induction of complement activation even after only a single session of hemodialysis. Importantly, complete inhibition of complement activation was achieved in response to two distinct Cp40 treatment regimens. Further, we show that application of Cp40 during hemodialysis resulted in increased levels of the anti-inflammatory cytokine IL-10, indicating that Cp40 may be a potent and cost-effective treatment option for attenuating chronic inflammatory conditions in dialysis-dependent patients.

Can serum NGAL levels be used as an inflammation marker on hemodialysis patients with permanent catheter?

BACKGROUND

Neutrophil gelatinase-associated lipocalin (NGAL) is a member of lipocalin family and released from many tissues and cells. We aimed to investigate the relationship among serum NGAL levels, the inflammation markers (IL-6, hs-CRP, TNF-α) and different vascular access types used in dialysis patients.

METHODS

The study population included 90 patients and 30 healthy age-matched controls. The patients were divided into three groups (I, II, III) and group IV included the controls. In group I and II, the patients were with central venous permanent catheter and arterio-venous fistula, respectively. Group III included 30 patients with chronic renal failure. Hemogram, biochemical assays, ferritin, IL-6, hs-CRP, TNF-α, and NGAL were evaluated in all groups.

RESULTS

Serum NGAL levels were markedly higher in group I than in group II (7645.80 ± 924.61 vs. 4131.20 ± 609.87 pg/mL; p < 0.05). Positive correlation was detected between NGAL levels and duration of catheter (r: 0.903, p: 0.000), hs-CRP (r: 0.796, p: 0.000), IL-6 (r: 0.687, p: 0.000), TNF-α (r: 0.568, p: 0.000) levels and ferritin (r: 0.318, p: 0.001), whereas NGAL levels were negatively correlated with serum albumin levels (r: -0.494, p: 0.000). In multiple regression analysis, duration of catheter hs-CRP and TNF-α were predictors of NGAL in hemodialysis patients.

CONCLUSION

Inflammation was observed in hemodialysis patients and increases with catheter. Our findings show that a strong relationship among serum NGAL levels, duration of catheter, hs-CRP and TNF-α. NGAL may be used as a new inflammation marker in hemodialysis patients.

Increased serum levels of GDF-15 associated with mortality and subclinical atherosclerosis in patients on maintenance hemodialysis

BACKGROUND/AIMS

Increased carotid intima-media thickness (CIMT) was shown to be an independent predictor of cardiovascular (CV) mortality in dialysis patients and the general population. Growth differentiation factor 15 (GDF-15), a member of the transforming growth factor superfamily, is produced by cardiomyocytes and atherosclerotic lesions under stress conditions such as inflammation. We assessed associations between serum concentrations of GDF-15, mortality, and CIMT for subclinical atherosclerosis in hemodialysis (HD) patients.

METHODS

A total of 87 patients on maintenance hemodialysis and 45 sex- and age-matched healthy controls were included in this prospective study. Serum GDF-15 levels were measured by ELISA. CIMT was assessed by Doppler ultrasonography. The association between serum GDF-15 levels and mortality was assessed using Cox regression analysis with serum levels categorized into two groups according to the median value (328.18 pg/ml). Patients were followed for 2 years and cause-specific and all-cause mortality were determined.

RESULTS

The median level of serum GDF-15 was significantly higher in HD patients than controls [328 (198-522) vs. 176 (101-289) pg/ml, p < 0.01, respectively]. Serum GDF-15 levels were correlated to CIMT (r = 0.607, p < 0.001), C-reactive protein (CRP; r = 0.250, p = 0.010), HD duration (r = 0.376, p = 0.004), and serum albumin (r = - 0.156, p = 0.030). The multivariate analysis revealed that GDF-15 was found to be an independent variable of CIMT in HD patients. In the study, the serum GDF-15 level was an independent marker of all-cause of mortality when adjusted for age, CRP, and history of diabetes mellitus.

CONCLUSION

The relationship between serum GDF-15, mortality, and carotid artery thickening suggests that GDF-15 may be a novel marker of atherosclerosis, inflammation, and malnutrition in HD patients.

Recent advances in the management of hemodialysis patients: a focus on cardiovascular disease

The number of patients requiring chronic hemodialysis is rapidly growing worldwide. Hemodialysis both greatly reduces quality of life and is associated with extremely high mortality rates. Management of care of patients requiring chronic hemodialysis is complex, and randomized controlled trials aimed at reducing primary outcomes of cardiovascular disease events, mortality, or both in this population have largely been unsuccessful. Topics of major concern in the management of maintenance hemodialysis patients as related to these outcomes include the overall cardiovascular disease burden, blood pressure control, anemia, abnormalities in mineral metabolism, and inflammation. The focus of this review is a discussion of these topics on the basis of current recommendations from major organizations, expert opinion, and the available randomized controlled trials to date. These issues are further complicated by sometimes conflicting observational and randomized controlled trial data. Overall, treatment options for reducing these endpoints in maintenance hemodialysis patients are limited, and future randomized controlled trials are essential to continuing to advance care in this population, with the goal of ultimately improving hard outcomes. Such trials should consider new therapies to better target these factors, additional risk factors that have not been well tested to date, and therapies with new targets, including inflammation.

The association of uremic toxins and inflammation in hemodialysis patients

BACKGROUND

Cardiovascular disease is the leading cause of mortality in hemodialysis patients and is associated with chronic inflammation. Elevation of uremic toxins, particular protein-bound uremic toxins, is a possible cause of hyper-inflammation in hemodialysis patients. But the association between uremic toxins and inflammatory markers in hemodialysis is still unclear.

METHODS

We conducted a cross-sectional study to evaluate the association of the serum uremic toxins and inflammatory markers in hemodialysis patients.

RESULTS

The uremic toxins were not associated with inflammatory markers--including high sensitivity C-reactive protein, IL(Interleukin) -1β, IL-6, tumor necrosis factor-α. In multiple linear regression, serum levels of total p-cresol sulfate (PCS) were independently significantly associated with serum total indoxyl sulfate (IS) (standardized coefficient: 0.274, p<0.001), and co-morbidity of diabetes mellitus (DM) (standardized coefficient: 0.342, p<0.001) and coronary artery disease (CAD) (standardized coefficient: 0.128, p = 0.043). The serum total PCS levels in hemodialysis with co-morbidity of DM and CAD were significantly higher than those without co-morbidity of DM and CAD (34.10±23.44 vs. 16.36±13.06 mg/L, p<0.001). Serum levels of total IS was independently significantly associated with serum creatinine (standardized coefficient: 0.285, p<0.001), total PCS (standardized coefficient: 0.239, p = 0.001), and synthetic membrane dialysis (standardized coefficient: 0.139, p = 0.046).

CONCLUSION

The study showed that serum levels of total PCS and IS were not associated with pro-inflammatory markers in hemodialysis patients. Besides, serum levels of total PCS were independently positively significantly associated with co-morbidity of CAD and DM.