Strong association between malnutrition, inflammation, and atherosclerosis in chronic renal failure

Geriatric Nutritional Risk Index is associated with adverse outcomes in patients with hypertension: the Fukushima Cohort study

Malnutrition is reportedly associated with adverse clinical outcomes in various populations. However, associations between nutritional status and adverse outcomes in patients with hypertension have not been sufficiently elucidated. We therefore aimed to investigate the impact of nutritional status as evaluated by the Geriatric Nutritional Risk Index (GNRI) on adverse outcomes in patients with hypertension. We conducted a retrospective cohort study of 1588 hypertensive patients enrolled in the Fukushima Cohort Study. Participants were categorized into tertiles (T1-T3) according to GNRI at baseline. The primary endpoint of the present study was a kidney event, defined as a combination of a 50% decline in eGFR from baseline and end-stage kidney disease requiring kidney replacement therapy. Associations between GNRI and kidney events were assessed using Kaplan-Meier curves and multivariate Cox regression analyses. Median age was 64 years, 55% were men, median eGFR was 63.1 mL/min/1.73 m2, and median GNRI was 101.3. The lower GNRI group (T1) showed an increased incidence of kidney events in the Kaplan-Meier curve analysis. Compared to the highest GNRI group (T3), lower GNRI carried a higher risk of kidney events for both T2 (hazard ratio [HR] 1.38, 95% confidence interval [CI] 0.71-2.68) and T1 (HR 3.59, 95%CI 1.96-6.63). Similar relationships were observed for risks of all-cause death and cardiovascular events. Lower GNRI was associated with kidney events, all-cause death, and cardiovascular events in patients with hypertension. Nutritional status as evaluated by GNRI could offer a simple and useful predictor of adverse outcomes in this population.

The predictive value of cardiovascular outcomes and mortality assessed by the C-reactive protein to albumin ratio in the UK Biobank

BACKGROUND

The C-reactive protein/albumin ratio (CAR) seems to mirror disease severity and prognosis in several acute disorders particularly in elderly patients, yet less is known about if CAR is superior to C-reactive protein (CRP) in the general population.

METHODS

Prospective study design on the UK Biobank, where serum samples of CRP and Albumin were used. Cox regression analyses were conducted to assess all-cause and cardiovascular mortality, myocardial infarction, ischemic stroke, and heart failure over a follow-up period of approximately 12.5 years. The Cox model was adjusted for established cardiovascular disease (CVD) risk factors, including age, sex, smoking habits, physical activity level, BMI level, systolic blood pressure, LDL-cholesterol, statin treatment, diabetes, and previous CVD, with hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). Analyses were also stratified by sex, CRP level (< 10 and ≥ 10 mg/ml) and age (< 60 and ≥ 60 years).

RESULTS

In total, 411,506 individuals (186,043 men and 225,463 women) were included. In comparisons between HRs for all adverse outcomes, the results were similar or identical for CAR and CRP. For example, both CAR and CRP, adjusted HRs for all-cause mortality were 1.13 (95% CI 1.12-1.14). Regarding CVD mortality, the adjusted HR for CAR was 1.14 (95% CI 1.12-1.15), while for CRP, it was 1.13 (95% CI 1.11-1.15).

CONCLUSIONS

Within this study CAR was not superior to CRP in predictive ability of mortality or CVD disorders.

CLINICAL TRIAL REGISTRATION NUMBER

Not applicable (cohort study).

Preventive dental care reduces risk of cardiovascular disease and pneumonia in hemodialysis population: a nationwide claims database analysis

This study aims to investigate the impact of dental care utilization status on the occurrence of fatal complications such as cerebral/cardiovascular disease (CVD) and infectious diseases in patients with end-stage renal disease (ESRD) undergoing hemodialysis. This retrospective cohort study was performed using the Japanese claims database and included patients who first underwent hemodialysis between April 2014 and September 2020. The exposure variable of interest was the pattern of dental utilization, which was categorized into three groups, "dental treatment group", "preventive dental care group", and "no-dental visit group". The primary outcomes were the time interval until a composite end point of first major cardiovascular event (acute myocardial infarction, heart failure, or cerebral infarction) of infectious disease (pneumonia and sepsis). The secondary outcomes were the time interval until the incidence of each component of primary outcomes. Survival analyses, including log-rank tests and Cox proportional hazards regression analyses, were performed. Among the 10,873 patients who underwent the first dialysis treatment, 6152 were assigned to the no-dental visit group, 2221 to the dental treatment group, and 2500 to the preventive dental care group. The preventive dental care group had significantly lower hazard ratios (HRs) of the incidence of CVD (adjusted hazard ratio [aHR]: 0.86, 95% confidence interval [CI]: 0.77-0.96) and infectious diseases (aHR: 0.86, 95% CI: 0.76-0.97). As for pneumonia, preventive dental care and dental treatment groups had significantly lower HRs (aHR: 0.74 and 0.80, 95% CI: 0.61-0.88, 0.66-0.96) than the no-dental visit group. This study demonstrated that dental visits for preventive dental care were associated with a significant risk reduction in CVD and infectious complications in patients with ESRD undergoing hemodialysis.

Skeletal Muscle Injury in Chronic Kidney Disease-From Histologic Changes to Molecular Mechanisms and to Novel Therapies

Chronic kidney disease (CKD) is associated with significant reductions in lean body mass and in the mass of various tissues, including skeletal muscle, which causes fatigue and contributes to high mortality rates. In CKD, the cellular protein turnover is imbalanced, with protein degradation outweighing protein synthesis, leading to a loss of protein and cell mass, which impairs tissue function. As CKD itself, skeletal muscle wasting, or sarcopenia, can have various origins and causes, and both CKD and sarcopenia share common risk factors, such as diabetes, obesity, and age. While these pathologies together with reduced physical performance and malnutrition contribute to muscle loss, they cannot explain all features of CKD-associated sarcopenia. Metabolic acidosis, systemic inflammation, insulin resistance and the accumulation of uremic toxins have been identified as additional factors that occur in CKD and that can contribute to sarcopenia. Here, we discuss the elevation of systemic phosphate levels, also called hyperphosphatemia, and the imbalance in the endocrine regulators of phosphate metabolism as another CKD-associated pathology that can directly and indirectly harm skeletal muscle tissue. To identify causes, affected cell types, and the mechanisms of sarcopenia and thereby novel targets for therapeutic interventions, it is important to first characterize the precise pathologic changes on molecular, cellular, and histologic levels, and to do so in CKD patients as well as in animal models of CKD, which we describe here in detail. We also discuss the currently known pathomechanisms and therapeutic approaches of CKD-associated sarcopenia, as well as the effects of hyperphosphatemia and the novel drug targets it could provide to protect skeletal muscle in CKD.

A clustering approach to improve our understanding of the genetic and phenotypic complexity of chronic kidney disease

Chronic kidney disease (CKD) is a complex disorder that causes a gradual loss of kidney function, affecting approximately 9.1% of the world's population. Here, we use a soft-clustering algorithm to deconstruct its genetic heterogeneity. First, we selected 322 CKD-associated independent genetic variants from published genome-wide association studies (GWAS) and added association results for 229 traits from the GWAS catalog. We then applied nonnegative matrix factorization (NMF) to discover overlapping clusters of related traits and variants. We computed cluster-specific polygenic scores and validated each cluster with a phenome-wide association study (PheWAS) on the BioMe biobank (n = 31,701). NMF identified nine clusters that reflect different aspects of CKD, with the top-weighted traits signifying areas such as kidney function, type 2 diabetes (T2D), and body weight. For most clusters, the top-weighted traits were confirmed in the PheWAS analysis. Results were found to be more significant in the cross-ancestry analysis, although significant ancestry-specific associations were also identified. While all alleles were associated with a decreased kidney function, associations with CKD-related diseases (e.g., T2D) were found only for a smaller subset of variants and differed across genetic ancestry groups. Our findings leverage genetics to gain insights into the underlying biology of CKD and investigate population-specific associations.

Handgrip strength and mortality in a cohort of kidney failure patients: Comparative analysis of different normalization methods

OBJECTIVES

Reduced handgrip strength (HGS) is associated with adverse clinical outcomes. We analyzed and compared associations of HGS with mortality risk in dialysis patients, using different normalization methods of HGS.

METHODS

HGS and clinical and laboratory parameters were measured in a cohort of 446 incident dialysis patients (median age 56 y, 62% men). The area under the receiver operating characteristic curve (AUROC) was used to compare different normalization methods of HGS as predictors of mortality: absolute HGS in kilograms; HGS normalized to height, weight, or body mass index; and HGS of a reference population of sex-matched controls (percentage of the mean HGS value [HGS%]). Multivariate linear regression analysis was used to assess HGS predictors. Competing risk regression analysis was used to evaluate 5-year all-cause mortality risk. Differences in survival time between HGS% tertiles were quantitated by analyzing the restricted mean survival time.

RESULTS

The AUROC for HGS% was higher than the AUROCs for absolute or normalized HGS values. Compared with the high HGS% tertile, low HGS% (subdistribution hazard ratio [sHR] = 2.36; 95% CI, 1.19-3.70) and middle HGS% (sHR = 1.79; 95% CI, 1.12-2.74) tertiles were independently associated with higher all-cause mortality and those with high HGS% tertile survived on average 7.95 mo (95% CI, 3.61-12.28) and 18.99 mo (95% CI, 14.42-23.57) longer compared with middle and low HGS% tertile, respectively.

CONCLUSIONS

HGS% was a strong predictor of all-cause mortality risk in incident dialysis patients and a better discriminator of survival than absolute HGS or HGS normalized to body size dimensions.

Investigational new drugs for the treatment of chronic renal failure: an overview of the literature

INTRODUCTION

Chronic kidney disease (CKD) is widespread throughout the world, with a high social and health impact. It is considered a 'silent killer' for its sudden onset without symptoms in the early stages of the disease. The main goal of nephrologists is to slow the progression of kidney disease and treat the associated symptoms with a range of new medications.

AREAS COVERED

The aim of this systematic review is to analyze the new investigational drugs for the treatment of chronic renal failure. Data were obtained from the available scientific literature and from the ClinicalTrials.gov website.

EXPERT OPINION

Among the drugs currently being researched, SGLT2 inhibitors appear to be the most promising drugs for the treatment of CKD, has they have slower progression of CKD and protection of cardiorenal function. An important role in the future of CKD treatment is played by autologous cell-therapy, which appears to be a new frontier in the treatment of CKD. Other therapeutic strategies are currently being investigated and have been shown to slow the progression of CKD. However, further studies are needed to determine whether these approaches may offer benefits in slowing the progression of CKD in the near future.

A simple score for malnutrition-inflammation complex syndrome (MICS) is associated with the risk of mortality in Japanese patients undergoing maintenance hemodialysis

INTRODUCTION

Malnutrition-inflammation complex syndrome (MICS) is highly prevalent in patients undergoing hemodialysis. We determined the prognostic value of the Simple MICS score, calculated using a combination of age, body mass index, and serum concentrations of albumin, creatinine, and C-reactive protein.

METHODS

We retrospectively recruited 218 Japanese patients undergoing maintenance hemodialysis. The primary outcome was all-cause mortality, and the main exposure was the Simple MICS score. Cox proportional hazard regression analysis and logistic regression analysis were used to characterize the relationship between the Simple MICS score and mortality.

RESULTS

During a median 4.4-year follow-up period, 56 patients died. Multivariable-adjusted models showed that a higher Simple MICS score was associated with higher risks of mortality. The predictability for all-cause mortality of the Simple MICS score was significantly better than conventional nutrition-related indices.

CONCLUSION

The Simple MICS score can be used to stratify mortality risk in patients undergoing maintenance hemodialysis.

Making the invisible visible: imaging techniques for assessing muscle mass and muscle quality in chronic kidney disease

Muscle wasting and low muscle mass are prominent features of protein energy wasting (PEW), sarcopenia and sarcopenic obesity in patients with chronic kidney disease (CKD). In addition, muscle wasting is associated with low muscle strength, impaired muscle function and adverse clinical outcomes such as low quality of life, hospitalizations and increased mortality. While assessment of muscle mass is well justified, the assessment of skeletal muscle should go beyond quantity. Imaging techniques provide the means for non-invasive, comprehensive, in-depth assessment of the quality of the muscle such as the infiltration of ectopic fat. These techniques include computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound. Dual energy X-ray absorptiometry is also an imaging technique, but one that only provides quantitative and not qualitative data on muscle. The main advantage of imaging techniques compared with other methods such as bioelectrical impedance analysis and anthropometry is that they offer higher precision and accuracy. On the other hand, the higher cost for acquiring and maintaining the imaging equipment, especially CT and MRI, makes these less-used options and available mostly for research purposes. In the field of CKD and end-stage kidney disease (ESKD), imaging techniques are gaining attention for evaluating muscle quantity and more recently muscle fat infiltration. This review describes the potential of these techniques in CKD and ESKD settings for muscle assessment beyond that of muscle quantity.

Association between Serum GDF-15 and Cognitive Dysfunction in Hemodialysis Patients

Cognitive dysfunction is more frequent in end-stage renal disease (ESRD) patients undergoing hemodialysis compared with the healthy population, emphasizing the need for early detection. Interest in serum markers that reflect cognitive function has recently increased. Elevated serum growth differentiation factor 15 (GDF-15) levels are known to be associated with an increased risk of decreased renal function and cognitive dysfunction. This study investigated the relationship between GDF-15 and cognitive dysfunction in hemodialysis patients using a retrospective analysis of 92 individuals aged ≥ 18 years. Cognitive function was assessed using the Korean version of the Mini-Mental Status Examination (K-MMSE), categorizing patients into normal (≥24 points) and cognitive dysfunction (<24 points). As a result, serum GDF-15 concentrations were at significantly higher levels in the cognitive dysfunction group (7500.42 pg/mL, p = 0.001). Logistic regression indicated an increased risk of K-MMSE scores < 24 points when serum GDF-15 exceeded 5408.33 pg/mL. After indoxyl sulfate exposure in HT22 cells, HT22 cells survival was decreased and GDF-15 expression in HT22 cells was increased. Similarly, exposure to indoxyl sulfate in mouse brain tissue resulted in an increased expression of GDF-15. This study highlights the potential of serum GDF-15 as a marker for cognitive dysfunction in hemodialysis patients, offering a valuable screening tool. Serum GDF-15 is related to cognitive dysfunction in hemodialysis patients and may be helpful in screening for cognitive dysfunction in hemodialysis patients.

Glasgow prognostic score as an outcome predictor for patients initiating hemodialysis

INTRODUCTION

This retrospective study examined the relationship between the Glasgow Prognostic Score (GPS) at hemodialysis (HD) initiation and overall/cardiovascular mortality.

METHODS

A total of 264 patients starting HD between 2014 and 2015 at a single center were studied. Follow-up persisted until therapy change, death, or study end (December 31, 2021), with a median of 6.8 years.

RESULTS

Patients with a higher GPS more frequently had emergent HD initiation and showed increased eGFR at initiation. During follow-up, 60% of patients died, with cardiovascular disease being the leading cause. Univariate analysis revealed a significant difference in median survival time across GPS classes. Cox proportional hazard models confirmed a significant association between GPS and mortality.

CONCLUSIONS

We report a significant association between GPS at HD initiation and mortality. GPS may prove useful as a prognostic tool for identifying high-risk patients, underscoring the need for future research to validate these findings and explore the potential of GPS-based interventions.

Navigating sarcopenia in COVID-19 patients and survivors: Understanding the long-term consequences, transitioning from hospital to community with mechanisms and interventions for future preparedness

The coronavirus disease 2019 (COVID-19) pandemic has caused widespread devastation, with millions of confirmed cases and deaths worldwide. Although there were efforts made to develop treatments and vaccines for COVID-19, the coexistence of sarcopenia, a muscle disorder, has been largely overlooked. It is while new variants of this disease (eg, BA.2.86) are challenging the current protocols. Sarcopenia is associated with increased mortality and disability, and shares common mechanisms with COVID-19, such as inflammation, hormonal changes, and malnutrition. This can worsen the effects of both conditions. Furthermore, survived patients with COVID-19 who have elevated risk, as well as aging, which increases the process of sarcopenia. Therefore, addressing sarcopenia in patients with COVID-19 and surviving individuals can be crucial for improving outcomes and preventing long-term disability. During hospital stays, assessing sarcopenia through indicators like muscle wasting and malnutrition is important. Nutritional interventions, such as malnutrition screening and enteral feeding, play a critical role in preventing sarcopenia in hospitals. Mental health and physical activity evaluations and interventions are also necessary. Even after recovering from COVID-19, there is a risk of developing sarcopenia, requiring continued monitoring. Nutrition and physical activity considerations are vital for prevention and management, necessitating tailored training programs and diet therapy. Mental health should not be overlooked, with regular screening, and community-based interventions. Infrastructure should support physical activity, and mental health services must become more accessible. Community engagement through support groups and peer networks can foster resilience and social connection. Efforts are needed to promote healthy diets and ensure access to nutritious foods.

Prognostic Factors in Children with Acute Kidney Injury Requiring Continuous Renal Replacement Therapy

INTRODUCTION

This study aimed to evaluate prognostic factors and outcomes in a single-center PICU cohort that received continuous renal replacement therapy (CRRT).

METHODS

This retrospective study analyzed clinical characteristics, laboratory data, and outcomes. Ninety-day mortality and advanced chronic kidney disease (CKD) (eGFR <60 mL/min/1.73 m2) were defined as primary and secondary outcomes, respectively.

RESULTS

Seventy-five patients were enrolled, all of whom received CRRT for indications including acute kidney injury with complicated refractory metabolic acidosis, electrolyte derangement, and existed or impending fluid overload. The 90-day mortality and advanced CKD were 53% and 29%, respectively. Multivariate Cox regression analysis demonstrated that only underlying bone marrow transplantation (BMT) (HR 4.58; 95% CI: 2.04-10.27) and a high pSOFA score (HR 1.12; 95% CI: 1.01-1.23) were independent risk factors for 90-day mortality. Among survivors, ten developed advanced CKD on the 90th day, and this group had a higher serum fibrinogen level (OR 1.01; 95% CI: 1.01-1.03) at the start of CRRT.

CONCLUSION

In critically ill children with AKI requiring CRRT, post-BMT and high pSOFA scores are independent risk factors for 90-day mortality. Additionally, a high serum fibrinogen level at the initiation of CRRT is associated with the development of advanced CKD.

Association between systemic immune inflammation Index and all-cause mortality in incident peritoneal dialysis-treated CKD patients: a multi-center retrospective cohort study

BACKGROUND

Chronic inflammatory disorders in peritoneal dialysis (PD) contribute to the adverse clinical outcome. Systemic immune inflammation index (SII) is the novel and convenient measurement that is positively associated with various diseases. However, scarce is known regarding the association between SII with all-cause mortality among PD patients.

METHODS

In this multi-center retrospective cohort study, 1,677 incident patients with PD were enrolled. Eligible patients were stratified into groups based on SII level: tertile 1(< 456.76), tertile 2(456.76 to 819.03), and tertile 3(> 819.03). The primary endpoint was the all-cause mortality. Both Cox regression analysis and competing risk models were used to examine the association between SII and all-cause mortality. Subgroup analysis was performed to assess the influence of the SII tertiles on all-cause mortality in different subgroups.

RESULTS

During the follow-up period of 30.5 ± 20.0 months, 26.0% (437/1,677) patients died, of whom the SII tertile 3 group accounted for 39.1% (171/437) of the deaths. Patients in the SII tertile 3 group had a higher all-cause mortality rate than patients in the SII tertile 1 and 2 groups (log-rank = 13.037, P < 0.001). The SII tertile 3 group was significantly associated with 80% greater risk (95% confidence interval:1.13 to 2.85; P = 0.013) compared with the SII tertile 1 group in multivariable Cox regression analysis. The competing risk model also indicated that the relationship between SII tertiles and all-cause mortality remains (subdistribution hazard ratio: 1.86; 95% confidence interval: 1.15 to 2.02, P = 0.011). Furthermore, the relationship between the log-transformed SII and all-cause mortality in patients with PD was nearly linear (P = 0.124).

CONCLUSION

A close relationship was observed between the SII and all-cause mortality in patients undergoing PD, suggesting that more attention should be paid to the SII, which is a convenient and effective measurement in clinical practice.

Chronic Kidney Disease Interplay with Comorbidities and Carbohydrate Metabolism: A Review

Chronic kidney disease (CKD) poses a global health challenge, engendering various physiological and metabolic shifts that significantly impact health and escalate the susceptibility to severe illnesses. This comprehensive review delves into the intricate complexities of CKD, scrutinizing its influence on cellular growth homeostasis, hormonal equilibrium, wasting, malnutrition, and its interconnectedness with inflammation, oxidative stress, and cardiovascular diseases. Exploring the genetic, birth-related, and comorbidity factors associated with CKD, alongside considerations of metabolic disturbances, anemia, and malnutrition, the review elucidates how CKD orchestrates cellular growth control. A pivotal focus lies on the nexus between CKD and insulin resistance, where debates persist regarding its chronological relationship with impaired kidney function. The prevalence of insulin abnormalities in CKD is emphasized, contributing to glucose intolerance and raising questions about its role as a precursor or consequence. Moreover, the review sheds light on disruptions in the growth hormone and insulin-like growth factor axis in CKD, underscoring the heightened vulnerability to illness and mortality in cases of severe growth retardation. Wasting, a prevalent concern affecting up to 75% of end-stage renal disease (ESRD) patients, is analyzed, elucidating the manifestations of cachexia and its impact on appetite, energy expenditure, and protein reserves. Taste disturbances in CKD, affecting sour, umami, and salty tastes, are explored for their implications on food palatability and nutritional status. Independent of age and gender, these taste alterations have the potential to sway dietary choices, further complicating the management of CKD. The intricate interplay between CKD, inflammation, oxidative stress, and cardiovascular diseases is unraveled, emphasizing the profound repercussions on overall health. Additionally, the review extends its analysis to CKD's broader impact on cognitive function, emotional well-being, taste perception, and endothelial dysfunction. Concluding with an emphasis on dietary interventions as crucial components in CKD management, this comprehensive review navigates the multifaceted dimensions of CKD, providing a nuanced understanding essential for developing targeted therapeutic strategies.

Low intensity pulsed ultrasound ameliorates Adriamycin-induced chronic renal injury by inhibiting ferroptosis

OBJECTIVE

It is very important to develop a new therapeutic strategy to cope with the increasing morbidity and mortality of chronic kidney disease (CKD). As a kind of physical therapy, low intensity pulsed ultrasound (LIPUS) has remarkable anti-inflammatory and repair-promoting effects and is expected to become a new therapeutic method for CKD. This study aims to clarify the treatment effect of LIPUS on CKD-related renal inflammation and fibrosis, and to further explore the potential signal network of LIPUS treatment for ameliorating chronic renal injury.

METHODS

A rat model simulating the progress of CKD was established by twice tail-vein injection of Adriamycin (ADR). Under anesthesia, bilateral kidneys of CKD rats were continuously stimulated by LIPUS for four weeks. The parameters of LIPUS were 1.0 MHz, 60 mW/cm2, 50% duty cycle and 20 min/d.

RESULTS

LIPUS treatment effectively inhibited ADR-induced renal inflammation and fibrosis, and improved CKD-related to oxidative stress and ferroptosis. In addition, the therapeutic effect of LIPUS is closely related to the regulation of TGF-β1/Smad and Nrf2/keap1/HO-1 signalling pathways.

DISCUSSION

This study provides a new direction for further mechanism research and lays an important foundation for clinical trials.

Association of serum thymosin β4 with malnutrition-inflammation-atherosclerosis syndrome in peritoneal dialysis patients: a cross-sectional study

BACKGROUND

Malnutrition-inflammation-atherosclerosis (MIA) syndrome may worsen the prognosis of peritoneal dialysis (PD) patients. Serum thymosin β4 (sTβ4) protects against inflammation, fibrosis and cardiac dysfunction.

OBJECTIVES

The present study aimed to characterize the association between sTβ4 and MIA syndrome as well as to investigate the potential of regulating sTβ4 to improve the prognosis of PD patients.

METHODS

We performed a cross-sectional, single-center pilot study involving 76 PD patients. Demographic characteristics, clinical characteristics, nutritional profiles, inflammatory mediators, atherosclerosis-related factors and sTβ4 levels were collected and subjected to association analysis for sTβ4 and MIA syndrome.

RESULTS

sTβ4 levels did not significantly vary with sex or primary disease in PD patients. Ages and PD features did not vary between patients with different levels of sTβ4. PD patients with higher levels of sTβ4 had significantly higher levels of nutritional indicators, including subjective global nutritional assessment (SGA) (p < 0.001) and serum albumin (ALB) (p < 0.001) but lower levels of inflammatory and atherosclerotic indicators, including serum C reaction protein (CRP) (p = 0.009), the right common carotid artery (RCCA) intimal thickness (p < 0.001) and the left common carotid artery (LCCA) intimal thickness (p = 0.02). Correlation analysis showed that sTβ4 was positively associated with SGA (p < 0.001) and serum ALB (p < 0.001) but negatively associated with CRP (p = 0.020), RCCA intimal thickness (p < 0.001) and LCCA intimal thickness (p = 0.033). In multiple adjusted models, the prevalence of MIA syndrome was significantly decreased in PD patients with increased levels of sTβ4 when patients without MIA syndrome were compared to those with all indicators of MIA syndrome (OR = 0.996, 95% CI 0.993-0.999, p = 0.003) or those with at least one indicator of MIA syndrome (OR = 0.997, 95% CI 0.995-0.998, p < 0.001).

CONCLUSIONS

The sTβ4 level decreases in PD patients with MIA syndrome. The prevalence of MIA syndrome decreases significantly as the level of sTβ4 increases in PD patients.

Association of a low ankle brachial index with progression to end-stage kidney disease in patients with advanced-stage diabetic kidney disease

INTRODUCTIONS

The effect of a low ankle-brachial index (ABI) in patients with advanced-stage diabetic kidney disease is not fully understood. This study investigates the prevalence of a low ABI in patients with advanced-stage diabetic kidney disease, which was defined as a urinary albumin-to-creatinine ratio (UACR) ≥300 mg/g and an estimated glomerular filtration rate (eGFR) between 15-60 mL/min/1.73 m². Furthermore, the association between a low ABI and end-stage kidney disease (ESKD) was determined.

METHODS

This single-center, retrospective, cohort study included 529 patients with advanced-stage diabetic kidney disease who were stratified into groups according to the ABI: high (>1.3), normal (0.9-1.3), and low (<0.9). The Kaplan-Meier method and Cox proportional analysis were used to examine the association between the ABI and ESKD.

RESULTS

A total of 42.5% of patients with a low ABI progressed to ESKD. A low ABI was associated with a greater risk of ESKD (hazard ratio (HR): 1.073). After adjusting for traditional chronic kidney disease risk factors, a low ABI remained associated with a greater risk of ESKD (HR: 1.758; 95% confidence interval: 1.243-2.487; p = 0.001).

CONCLUSIONS

These results indicate that patients with a low ABI should be monitored carefully. Furthermore, preventive therapy should be considered to improve the long-term kidney survival of patients with residual kidney function.

The correlation between serum growth differentiation factor 15 and malnutrition in patients with end-stage kidney disease on hemodialysis

OBJECTIVE

Malnutrition commonly occurs in patients undergoing maintenance hemodialysis. Early detection of malnutrition could allow early interventions to prevent later complications. At present, there are not many biomarkers with high predictive value of end-stage kidney disease (ESKD)-related malnutrition, especially for early malnutrition in hemodialysis patients, which needs more in-depth research. Therefore, we performed a cross-sectional study on 97 patients to identify biomarkers for malnutrition in hemodialysis patients.

RESEARCH METHODS & PROCEDURES

7-point subjective global assessment (SGA) was applied to evaluate the nutritional status of patients on hemodialysis. Serum levels of growth differentiation factor 15 (GDF15), albumin, pre-albumin, c-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), hemoglobin, low density lipoprotein-cholesterol, and high density lipoprotein-cholesterol were detected before hemodialysis. Logistic analysis and linear regression were used to analyze the association between GDF15 levels and the SGA score after adjustment for basic characteristics and laboratory findings.

RESULTS

Among the 97 patients on hemodialysis, 51 had malnutrition (SGA < 6). There was no difference between the malnourished and well nourished (SGA ≥ 6) groups for dialysis duration, cholesterol, CRP, TNF-α, and hemoglobin. The malnutrition group had significantly lower grip strength (p < 0.05). GDF15 levels correlated negatively with the SGA score after adjustment for possible confounding factors [rho (male) = -0.312, rho(female)= -0.437;P(male) = 0.0181, P(female) = 0.005], and might contribute to the malnutritional status, the AUCs of GDF15 for malnutrition was 0.697 (p = 0.011) in male and 0.828 (p < 0.001) in female.

CONCLUSIONS

GDF15 is associated with malnutrition according to the SGA score in patients with ESKD on hemodialysis, suggesting that GDF15 might be involved in the pathogenesis of malnutrition patients with ESKD in this setting. Furthermore, GDF15 is likely to be a potential diagnostic biomarker for malnutrition according to the SGA score.

Association between High Bleeding Risk and 2-Year Mortality in Patients with Chronic Limb-Threatening Ischemia

AIM

Patients with chronic limb-threatening ischemia (CLTI) have a high bleeding risk (HBR) and mortality rate. The 2-year life expectancy is an important factor in deciding the appropriate treatment strategy. This study aimed to assess the influence of HBR on the prognosis of patients with CLTI.

METHODS

A total of 259 patients with CLTI who underwent endovascular therapy (EVT) (mean age, 76.2 years; male, 62.9%) between January 2018 and December 2019 were evaluated. The Academic Research Consortium for HBR (ARC-HBR) criteria were applied to each patient, and the ARC-HBR scores were calculated. The cut-off score for predicting all-cause mortality within two years was derived using a survival classification and regression tree (CART) model. Causes of death and the association between ARC-HBR scores and major bleeding events within two years were also investigated.

RESULTS

Based on the CART model, patients were divided into three groups (low HBR score 0-1.0, 48 patients; moderate HBR score 1.5-3.0, 176 patients; and high HBR score ≥ 3.5, 35 patients). During the study period, 82 patients (39.6%) died due to cardiac (n=23) and non-cardiac causes (n=59). All-cause mortality increased significantly with increasing ARC-HBR scores. Cox multivariate analysis revealed a significant association between high ARC-HBR scores and the risk of all-cause mortality within two years. Major bleeding events increased significantly with increasing ARC-HBR scores.

CONCLUSIONS

The ARC-HBR score could predict 2-year mortality in patients with CLTI who underwent EVT. Thus, this score can help determine the best revascularization strategy for patients with CLTI.

The C-reactive protein Albumin ratio was not consistently associated with cardiovascular and all-cause mortality in two community-based cohorts of 70-year-olds

C-reactive protein (CRP)/Albumin ratio (CAR) seems to mirror disease severity and prognosis in several acute disorders particularly in elderly patients, which we aimed to study. As method we use a prospective study design; the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS; n = 912, women 50%; mean age 70 years, baseline 2001 and 2004, median follow-up 15.0 years, end of follow-up 2019) and the Uppsala Longitudinal Study of Adult Men (ULSAM, n = 924 mean age 71 years, baseline 1991-1995, median follow-up 15.6 years, end of follow-up 2016). Serum samples were used for analyses of CRP and Albumin. Cox regression analyses were performed for cardiovascular and all-cause mortality in models adjusting for several factors (age; physical activity; Interleukin-6; cardiovascular (CVD) risk factors: smoking, BMI level, systolic blood pressure, LDL-cholesterol, and diabetes), with 95% confidence interval (CI). When adjusting for age and CVD risk factors, CAR was significantly associated with cardiovascular mortality for meta-analyzed results from PIVUS and ULSAM, HR 1.09 (95% 1.01-1.18), but neither in PIVUS (HR 1.14, 95% CI 0.99-1.31) nor in ULSAM (1.07, 95% CI 0.98-1.17). Additionally, CAR was significantly associated with all-cause mortality in ULSAM 1.31 (95% CI 1.12-1.54) but not in PIVUS HRs 1.01 (95% 0.089-1.15). The predictive value of CAR was similar to CRP alone in PIVUS and ULSAM and slightly better than albumin for the prediction of CVD-mortality in ULSAM. In conclusion, CAR was not consistently associated with cardiovascular and all-cause mortality in the two cohorts. The prognostic value of CAR for long-term CVD-mortality was similar to CRP.

MicroRNA regulators of vascular pathophysiology in chronic kidney disease

Coronary artery disease (CAD) is a severe comorbidity in chronic kidney disease (CKD) due to heavy calcification in the medial layer and inflamed plaques. Chronic inflammation, endothelial dysfunction and vascular calcification are major contributors that lead to artherosclerosis in CKD. The lack of specific symptoms and signs of CAD and decreased accuracy of noninvasive diagnostic tools result in delayed diagnosis leading to increased mortality. MicroRNAs (miRNAs) are post-transcriptional regulators present in various biofluids throughout the body. In the circulation, miRNAs have been reported to be encapsulated in extracellular vesicles and serve as stable messengers for crosstalk among cells. miRNAs are involved in pathophysiologic mechanisms including CAD and can potentially be extended from basic research to clinical translational practice.

A Study of Oxidative Stress, Inflammation, and Endothelial Dysfunction in Diabetic and Nondiabetic Chronic Kidney Disease Pre-Dialysis Patients

Background

Oxidative stress, inflammation, and endothelial dysfunction represent a key triad for the development and progression of atherosclerosis. Due to chronic low-grade inflammation in chronic kidney disease (CKD), concentrations of various inflammatory, endothelial, and oxidative stress markers are elevated, increasing the risk of atherosclerosis. The present study was undertaken to compare oxidative stress, inflammation, and endothelial dysfunction in diabetic and nondiabetic CKD pre-dialysis patients.

Materials and Methods

This was an observational study on 120 CKD pre-dialysis patients: 60 with diabetes and 60 without diabetes. Markers of oxidative stress were measured in blood - malondialdehyde (MDA), ferric reducing ability of plasma (FRAP), paroxonase-1 (PON-1), ischemia-modified albumin (IMA); inflammation - interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP); and endothelial dysfunction - nitric oxide (NO), carotid wall intima-media thickness (CIMT). Comparisons between the two groups for continuous variables were made with the Student's unpaired t-test or Mann-Whitney test and for categorical values with χ2-test, as appropriate.

Results

MDA, IMA, IL-6, hsCRP, NO, and CIMT were significantly higher, while FRAP and PON-1 were significantly lower in the diabetic group when compared to nondiabetic group (P < 0.001). The number of atherosclerotic plaques was also significantly higher in the diabetic group compared to nondiabetic group.

Conclusion

Our study showed increased oxidative stress, inflammation, endothelial dysfunction, and atherosclerosis in diabetic CKD pre-dialysis patients when compared to nondiabetic CKD pre-dialysis patients and in late stages when compared to early stages of CKD in both groups, indicating increased cardiovascular risk in late stages and diabetic CKD pre-dialysis patients.

Increased risk of chronic kidney disease in uric acid stone formers with high neutrophil-to-lymphocyte ratio

Urolithiasis is associated with an increased risk of chronic kidney disease (CKD), irrespective of stone compositions. Chronic inflammation is an important factor for CKD progression. Neutrophil-to-lymphocyte ratio (NLR) has been recognized as a reliable biomarker of inflammation, yet its use in predicting renal deterioration in patients with urolithiasis remains limited. We aimed to explore whether the combination of stone composition and NLR could be useful as a predictor for CKD risk. A total of 336 stone formers with at least one stone submission for analysis were enrolled in the retrospective study. Stones were classified into uric acid and calcium groups. Renal functions were assessed at least one month after stone treatment. Uric acid stone formers had significantly lower estimated glomerular filtration rate (eGFR) compared with calcium stone formers (p < 0.001). NLR was significantly higher in uric acid stone formers (p = 0.005), and a significantly negative correlation (p < 0.001) between NLR and eGFR had been observed only in uric acid stone group. Univariate and multivariate logistic regression analyses showed that higher proportion of uric acid stone composition and higher NLR were both significantly associated with CKD risks. A nomogram integrating independent predictors was generated for CKD prediction, yielding an AUC of 0.811 (0.764-0.858). In conclusion, our study demonstrated that stone formers with higher proportion of uric acid composition and higher NLR levels were associated with higher CKD risk.

A clustering approach to improve our understanding of the genetic and phenotypic complexity of chronic kidney disease

Chronic kidney disease (CKD) is a complex disorder that causes a gradual loss of kidney function, affecting approximately 9.1% of the world's population. Here, we use a soft-clustering algorithm to deconstruct its genetic heterogeneity. First, we selected 322 CKD-associated independent genetic variants from published genome-wide association studies (GWAS) and added association results for 229 traits from the GWAS catalog. We then applied nonnegative matrix factorization (NMF) to discover overlapping clusters of related traits and variants. We computed cluster-specific polygenic scores and validated each cluster with a phenome-wide association study (PheWAS) on the BioMe biobank (n=31,701). NMF identified nine clusters that reflect different aspects of CKD, with the top-weighted traits signifying areas such as kidney function, type 2 diabetes (T2D), and body weight. For most clusters, the top-weighted traits were confirmed in the PheWAS analysis. Results were found to be more significant in the cross-ancestry analysis, although significant ancestry-specific associations were also identified. While all alleles were associated with a decreased kidney function, associations with CKD-related diseases (e.g., T2D) were found only for a smaller subset of variants and differed across genetic ancestry groups. Our findings leverage genetics to gain insights into the underlying biology of CKD and investigate population-specific associations.

A clustering approach to improve our understanding of the genetic and phenotypic complexity of chronic kidney disease

Chronic kidney disease (CKD) is a complex disorder that causes a gradual loss of kidney function, affecting approximately 9.1% of the world's population. Here, we use a soft-clustering algorithm to deconstruct its genetic heterogeneity. First, we selected 322 CKD-associated independent genetic variants from published genome-wide association studies (GWAS) and added association results for 229 traits from the GWAS catalog. We then applied nonnegative matrix factorization (NMF) to discover overlapping clusters of related traits and variants. We computed cluster-specific polygenic scores and validated each cluster with a phenome-wide association study (PheWAS) on the BioMe biobank (n=31,701). NMF identified nine clusters that reflect different aspects of CKD, with the top-weighted traits signifying areas such as kidney function, type 2 diabetes (T2D), and body weight. For most clusters, the top-weighted traits were confirmed in the PheWAS analysis. Results were found to be more significant in the cross-ancestry analysis, although significant ancestry-specific associations were also identified. While all alleles were associated with a decreased kidney function, associations with CKD-related diseases (e.g., T2D) were found only for a smaller subset of variants and differed across genetic ancestry groups. Our findings leverage genetics to gain insights into the underlying biology of CKD and investigate population-specific associations.

Cardiovascular Calcifications Are Correlated with Inflammation in Hemodialysis Patients

Background and Objectives: The main cause of morbidity and mortality in hemodialysis patients is cardiovascular disease, which is quite common. The main objective of our study was to investigate the relationship between oxidative stress, inflammation, and vascular and valvular calcifications in hemodialysis patients. Materials and Methods: This observational study had 54 hemodialysis patients, with an average age of 60.46 ± 13.18 years. Cardiovascular ultrasound was used to detect and/or measure aortic and mitral valve calcifications, carotid and femoral atheroma plaques, and common carotid intima-media thickness. The aortic calcification score was determined using a lateral abdomen plain radiograph. The inflammatory, oxidative, metabolic, and dietary statuses, as well as demographic characteristics, were identified. Results: There were significant correlations between the levels of IL-6 and carotid plaque number (p = 0.003), fibrinogen level and aortic valve calcifications (p = 0.05), intima-media thickness (p = 0.0007), carotid plaque number (p = 0.035), femoral plaque number (p = 0.00014), and aortic calcifications score (p = 0.0079). Aortic annulus calcifications (p = 0.03) and intima-media thickness (p = 0.038) were adversely linked with TNF-α. Nutrition parameters were negatively correlated with atherosclerosis markers: number of carotid plaques with albumin (p = 0.013), body mass index (p = 0.039), and triglycerides (p = 0.021); number of femoral plaques with phosphorus (0.013), aortic calcifications score with albumin (p = 0.051), intima-media thickness with LDL-cholesterol (p = 0.042). Age and the quantity of carotid plaques, femoral plaques, and aortic calcifications were linked with each other (p = 0.0022, 0.00011, and 0.036, respectively). Aortic annulus calcifications (p = 0.011), aortic valve calcifications (p = 0.023), and mitral valve calcifications (p = 0.018) were all associated with an increased risk of death. Conclusions: Imaging measures of atherosclerosis are adversely connected with dietary status and positively correlated with markers of inflammation and risk of mortality.

Factors associated with elevated blood lactate levels in patients undergoing maintenance hemodialysis

Factors associated with chronic elevation of the blood lactate levels in patients undergoing chronic maintenance hemodialysis (hereinafter, hemodialysis patients) have not yet been thoroughly investigated. The purpose of the present study was to clarify factors associated with elevated blood lactate levels in hemodialysis patients. We divided the hemodialysis patients into two groups according the blood lactate levels (the high blood lactate group [> 2 mmol/L] and normal blood lactate group), and conducted a retrospective comparison of the following items between the two groups: (1) the creatinine generation rate (%CGR) and the geriatric nutrition risk index (GNRI) as indices of the nutritional status; (2) the left ventricular ejection fraction (LVEF) and E/A, an indicator of diastolic function; (3) the ankle-brachial index (ABI) and transcutaneous partial pressure of oxygen as indices of the adequacy of circulation in the peripheral blood vessels of the lower extremities; (4) the white blood cell count and serum level of C-reactive protein (CRP) before dialysis as markers of an inflammatory state. The mean age and serum CRP level were significantly higher in the high blood lactate group than in the normal blood lactate group. There were no significant differences in the markers of the nutritional status, cardiac function, or adequacy of circulation in the peripheral blood vessels of the lower extremities between the two groups. Advanced age and a state of chronic inflammation appear to be associated with elevated blood lactate levels in patients undergoing chronic maintenance hemodialysis.

Prognostic impacts of geriatric nutritional risk index in patients with ischemic heart failure after percutaneous coronary intervention

BACKGROUND

Malnutrition has been proven to be associated with increased risk of poor prognosis in a series of diseases. This study explored the association between poor nutritional status and prognosis in patients with ischemic heart failure (IHF) undergoing percutaneous coronary intervention (PCI).

METHODS

The study enrolled 1745 patients with IHF undergoing PCI. The mean follow-up time was 28.7 months. Nutritional status was assessed by geriatric nutritional risk index (GNRI). All patients were divided into four groups according to GNRI quartiles (median and interquartile range: 103.8, 99.9-107.7). The primary endpoint was major adverse cardiovascular events (MACE), and the secondary endpoints were each component of the primary endpoint as follows: all-cause mortality, non-fatal myocardial infarction (MI), and any revascularization. The Kaplan-Meier survival analyses were performed to evaluate the incidence of the endpoints among 4 groups. The multivariate Cox proportional hazards analysis confirmed the independent effect of GNRI on the primary endpoint and secondary endpoints. The restricted cubic spline (RCS) was performed to evaluate the non-linear association of GNRI with MACE.

RESULT

The negative correlation of the GNRI with MACE (Log-rank P < 0.001), all-cause mortality (Log-rank P < 0.001) and any revascularization (Log-rank P < 0.001) was confirmed through the Kaplan-Meier curves. Multivariate analysis showed that the decreased GNRI was independently related to increased risk of MACE (Quartile 1 versus Quartile 4: HR, 95% CI: 2.66, 2.01-3.51, P < 0.001), all-cause mortality (Quartile 1 versus Quartile 4: HR, 95% CI: 2.33, 1.54-3.50, P < 0.001) and any revascularization (Quartile 1 versus Quartile 4: HR, 95% CI: 3.42, 2.22-5.27, P < 0.001). In addition, the non-linear association of GNRI with MACE was shown through RCS and the risk of MACE decreased as the GNRI increased in general (Non-linear P < 0.001).

CONCLUSION

Decreased GNRI was an independent risk factor of MACE in IHF patients undergoing PCI.

Coronary artery calcification and aortic valve calcification in patients with kidney failure: a sex-disaggregated study

BACKGROUND

Chronic kidney disease (CKD) is linked to an increased cardiovascular disease (CVD) burden. Albeit underappreciated, sex differences are evident in CKD with females being more prone to CKD development, but males progressing more rapidly to kidney failure (KF). Cardiovascular remodelling is a hallmark of CKD with increased arterial and valvular calcification contributing to CKD. However, little is known regarding sex differences in calcific cardiovascular remodelling in KF patients. Thus, we hypothesise that sex differences are present in coronary artery calcification (CAC) and aortic valve calcification (AVC) in patients with KF.

METHODS

KF patients, males (n = 214) and females (n = 107), that had undergone computer tomography (CT) assessment for CAC and AVC were selected from three CKD cohorts. All patients underwent non-contrast multi-detector cardiac CT scanning, with CAC and AVC scoring based on the Agatston method. Baseline biochemical measurements were retrieved from cohort databases, including plasma analyses for inflammation markers (IL-6, TNF, hsCRP) and oxidative stress by skin autofluorescence measuring advanced glycation end-products (AGE), amongst other variables.

RESULTS

Sex-disaggregated analyses revealed that CAC score was associated with age in both males and females (both p < 0.001). Age-adjusted analyses revealed that in males CAC was associated with diabetes mellitus (DM) (p = 0.018) and CVD (p = 0.011). Additionally, for females CAC associated with IL-6 (p = 0.005) and TNF (p = 0.004). In both females and males CAC associated with AGE (p = 0.042 and p = 0.05, respectively). CAC was associated with mortality for females (p = 0.015) independent of age. AVC in females was not reviewed due to low AVC-positive samples (n = 14). In males, in multivariable regression AVC was associated with age (p < 0.001) and inflammation, as measured by IL-6 (p = 0.010).

CONCLUSIONS

In female KF patients inflammatory burden and oxidative stress were associated with CAC. Whereas in male KF patients oxidative stress and inflammation were associated with CAC and AVC, respectively. Our findings suggest a sex-specific biomarker signature for cardiovascular calcification that may affect the development of cardiovascular complications in males and females with KF.

The Contribution of Muscle Innate Immunity to Uremic Cachexia

Protein energy wasting (PEW) is a common complication both in chronic kidney disease (CKD) and end-stage kidney disease (ESKD). Of note, PEW is one of the stronger predictors of morbidity and mortality in this patient population. The pathogenesis of PEW involves several mechanisms, including anorexia, insulin resistance, acidosis and low-grade inflammation. In addition, "sterile" muscle inflammation contributes to PEW at an advanced CKD stage. Both immune and resident muscle cells can activate innate immunity; thus, they have critical roles in triggering "sterile" tissue inflammation. Toll-like receptor 4 (TLR4) can detect endogenous danger-associated molecular patterns generated or retained in blood in uremia and induce a sterile muscle inflammatory response via NF-κB in myocytes. In addition, TLR4, though the activation of the NLRP3 inflammasome, links the sensing of metabolic uremic stress in muscle to the activation of pro-inflammatory cascades, which lead to the production of IL-1β and IL-18. Finally, uremia-induced accelerated cell senescence is associated with a secretory phenotype that favors fibrosis in muscle. Targeting these innate immune pathways could lead to novel therapies for CKD-related PEW.

Emerging evidence on the role of clonal hematopoiesis of indeterminate potential in chronic kidney disease

Chronic kidney disease (CKD) was responsible for 1.2 million deaths globally in 2016. Despite the large and growing burden of CKD, treatment options are limited and generally only preserve kidney function. Characterizing molecular precursors to incident and progressive CKD could point to critically needed prevention and treatment strategies. Clonal hematopoiesis of indeterminate potential (CHIP) is typically characterized by the clonal expansion of blood cells carrying somatic mutations in specific driver genes. An age-related disorder, CHIP is rare in the young but common in older adults. Recent studies have identified causal associations between CHIP and atherosclerotic cardiovascular disease which are most likely mediated by inflammation, a hallmark of CKD. Animal evidence has supported causal effects of CHIP on kidney injury, inflammation, and fibrosis, providing impetus for human research. Although prospective epidemiologic studies investigating associations of CHIP with development and progression of CKD are few, intriguing findings have been reported. CHIP was significantly associated with kidney function decline and end stage kidney disease in the general population, although effect sizes were modest. Recent work suggests larger associations of CHIP with kidney disease progression in CKD patients, but further investigations in this area are needed. In addition, the accumulating literature has identified some heterogeneity in associations between CHIP and kidney endpoints across study populations, but reasons for these differences remain unclear. The current review provides an in-depth exploration into this nascent area of research, develops a conceptual framework linking CHIP to CKD, and discusses the clinical and public health implications of this work.

Interleukin-6-to-Albumin Ratio as a Superior Predictor of Mortality in End-Stage Kidney Disease Patients

INTRODUCTION

In patients with chronic kidney disease (CKD), high interleukin-6 (IL-6) and low albumin circulating concentrations are associated with worse outcomes. We examined the IL-6-to-albumin ratio (IAR) as a predictor of risk of death in incident dialysis patients.

METHODS

In 428 incident dialysis patients (median age 56 years, 62% men, 31% diabetes mellitus, 38% cardiovascular disease [CVD]), plasma IL-6 and albumin were measured at baseline to calculate IAR. We compared the discrimination of IAR with other risk factors for predicting 60-month mortality using receiver operating characteristic curve (ROC) and analyzed the association of IAR with mortality using Cox regression analysis. We divided patients into IAR tertiles and analyzed: (1) cumulative incidence of mortality and the association of IAR with mortality risk in Fine-Gray analysis, taking kidney transplantation as competing risk and (2) the restricted mean survival time (RMST) to 60-month mortality and differences of RMST (∆RMST) between IAR tertiles to describe quantitative differences of survival time.

RESULTS

For all-cause mortality, the area under the ROC curve (AUC) for IAR was 0.700, which was greater than for IL-6 and albumin separately, while for CV mortality, the AUC for IAR (0.658) showed negligible improvement over IL-6 and albumin separately. In Cox regression analysis, IAR was significantly associated with all-cause mortality but not with CV mortality. Both high versus low and middle versus low tertiles of IAR associated with higher risk of all-cause mortality, subdistribution hazard ratio of 2.22 (95% CI 1.40-3.52) and 1.85 (95% CI 1.16-2.95), respectively, after adjusting for age, sex, diabetes mellitus, CVD, smoking, and estimated glomerular filtration rate. ∆RMST at 60 months showed significantly shorter survival time in middle and high IAR tertiles compared with low IAR tertile for all-cause mortality.

CONCLUSIONS

Higher IAR was independently associated with significantly higher all-cause mortality risk in incident dialysis patients. These results suggest that IAR may provide useful prognostic information in patients with CKD.

The role of decoy receptor 3 in inflammation and atherosclerosis in patients with chronic kidney disease and renal transplant patients

INTRODUCTION

The cardiovascular risk has been increased in chronic kidney disease associated with chronic inflammation and atherosclerosis. Decoy receptor 3, is a member of the TNF receptor superfamily and associated with inflammation and atherosclerosis. The aim of our study is to determine the relationship, between serum DcR3 levels and inflammatory markers in patients with renal transplantation, those receiving dialysis treatment and cases with chronic renal failure that did not receive replacement therapy, and to evaluate their correlation with USG findings.

MATERIAL AND METHODS

A total of 150 patients aged between 22-86 years, consisting of 4 groups, namely renal transplantation, dialysis, predialysis chronic kidney disease and control groups, were included in the study. Serum decoy receptor 3, VCAM-1, ICAM-1 and IL-8 measured with ELISA method. Carotid intima-media thickness and presence of carotis arter plaque performed by ultrasound probe, non-invasively.

RESULTS

All serum markers were higher in dialysis and pre-dialysis chronic kidney disease groups compared to renal transplant and control groups (p<0.05). Serum decoy receptor 3 level (median(min-max)) of renal transplant group (0.49ng/mL (0.19-1.65)) was higher than control group (0.35ng/mL (0.19-2.22)). There was no difference between patients receiving dialysis (0.89ng/mL (0.41-4.98)) and patients with pre-dialysis chronic kidney disease (0.71ng/mL (0.29-1.68)). There was no difference between patient groups in terms of the presence of plaque.

CONCLUSION

Although renal transplantation provides a significant improvement in the inflammatory process, not return completely. Inflammatory process associated with uremic milieu may predispose to atherosclerosis in patients with pre-dialysis chronic kidney disease and hemodialysis patients.

Adipose tissue metabolic changes in chronic kidney disease

Adipose tissue is a complex organ whose functions go beyond being an energy reservoir to sustain proper body energy homeostasis. Functioning as an endocrine organ, the adipose tissue has an active role in the body's metabolic balance regulation through several secreted factors generally termed as adipokines. Thus, adipose tissue dysregulation in chronic kidney disease (CKD) can have a deep impact in the pathophysiology of diseases associated with metabolic dysregulation including metabolic syndrome, insulin resistance (IR), atherosclerosis, and even cachexia. CKD is a progressive disorder linked to increased morbidity and mortality. Despite being characterized by renal function loss, CKD is accompanied by metabolic disturbances such as dyslipidemia, protein energy wasting, chronic low-grade inflammation, IR, and lipid redistribution. Thus far, the mechanisms by which these changes occur and the role of adipose tissue in CKD development and progression are unclear. Further understanding of how these factors develop could have implications for the management of CKD by helping identify pharmacological targets to improve CKD outcomes.

Simplified geriatric nutritional risk index for assessing nutritional status and stratifying mortality risk in patients receiving maintenance hemodialysis

INTRODUCTION

The geriatric nutritional risk index (GNRI) is a widely used tool for nutritional assessment in patients receiving hemodialysis. The simplification of the GNRI calculation would be more useful for easier screening of malnutrition and for providing an intuitive stratification of mortality risk.

METHODS

We retrospectively evaluated 218 Japanese patients receiving maintenance hemodialysis at two hemodialysis centers. The primary outcome was all-cause mortality. The main exposure was a simplified GNRI (sGNRI) calculated as follows: sGNRI = serum albumin (g/dL) + 0.1 × body mass index (kg/m² ).

RESULTS

During the median 4.4-year follow-up, 56 patients died. Multivariable-adjusted Cox proportional hazard risk models showed that patients with a lower sGNRI showed a significantly increased mortality risk. No significant difference was observed between the original GNRI and sGNRI regarding mortality predictability.

CONCLUSION

sGNRI is as useful as the original GNRI for screening for malnutrition and stratifying hemodialysis patients at increased mortality risk.

Malnutrition and Insulin Resistance May Interact with Metabolic Syndrome in Prevalent Hemodialysis Patients

Background: We sought to determine the prevalence of metabolic syndrome (Mets) and whether 100 cm2 of visceral fatty area (VFA) measured by computed tomography (CT) validates the criteria of waist circumference (WC) in hemodialysis (HD) patients. Methods: The study comprised 141 HD patients. Mets was defined according to the criteria of Adult Treatment Panel III (ATP III) and the modified criteria of National Cholesterol Education Program (NCEP) that defines abdominal obesity as a WC of >=85 cm in men and >=90 cm in women. Results: The prevalence of Mets was 31.9% in men and 13.6% in women. However, the prevalence of patients with a body mass index over 25 in all HD patients was only 11.2%. The visceral fatty area (VFA) measured by CT showed a strong positive correlation with WC. The patients with Mets, comparing with those without Mets, have significantly shorter duration of HD, higher high-sensitive C-reactive protein, and higher Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). In the patients with Mets, there was a significant negative correlation between HOMA-IR and serum albumin levels. Multivariate logistic regression analysis showed that HOMA-IR and short duration of HD were chosen as independent risk factors for Mets. Conclusions: Mets is more prevalent in HD patients. In Japanese HD patients, 100 cm2 of VFA corresponded to a WC of 85 cm in men and 90 cm in women, thus confirming the validity of the modified criteria. HOMA-IR and serum albumin were significantly correlated in HD patients with Mets.

Low-Plasma Insulin-Like Growth Factor-1 Associates With Increased Mortality in Chronic Kidney Disease Patients With Reduced Muscle Strength

OBJECTIVES

Chronic kidney disease (CKD) leads to metabolic and nutritional abnormalities including resistance to insulin-like growth factor-1 (IGF-1) action, and reduced muscle mass and strength. Low IGF-1 as well as low hand-grip muscle strength (HGS) are independent predictors of increased mortality in CKD patients.

METHODS

In 685 patients (CKD Stage 3-5, median age 58 years; 62% men), baseline measurements of IGF-1, HGS, subjective global assessment (SGA), lean body mass index (LBMI), and metabolic and inflammatory biomarkers potentially linked to IGF-1 were analyzed in relation to mortality during 5 years of follow-up. We compared survival in 4 groups with high or low (cut-offs defined by receiver operating characteristic curve analysis) levels of IGF-1 and HGS.

RESULTS

Patients with low IGF-1 were older; had lower BMI, HGS, and LBMI, were more likely to have diabetes, cardiovascular disease (CVD), and malnutrition (SGA >1); and had high-sensitivity C-reactive protein levels. During 5 years of follow-up, 208 patients died. The mortality rate was highest among patients with Low IGF-1 + Low HGS. In competing-risk regression analysis, Low IGF-1 + Low HGS was independently associated with 2.8 times higher all-cause mortality risk than Low IGF-1 + High HGS, after adjusting for Framingham's CVD risk score, presence of CVD, SGA, dialysis status, high-sensitivity C-reactive protein, albumin, LBMI, and sample time in freezer.

CONCLUSION

Low IGF-1 was associated with increased all-cause mortality in patients who also had low HGS but not in those with high HGS, suggesting that the association of IGF-1 with survival in CKD patients depends on nutritional status.

Positive Correlation between Relative Concentration of Spermine to Spermidine in Whole Blood and Skeletal Muscle Mass Index: A Possible Indicator of Sarcopenia and Prognosis of Hemodialysis Patients

Several mechanisms strictly regulate polyamine concentration, and blood polyamines are excreted in urine. This indicates polyamine accumulation in renal dysfunction, and studies have shown increased blood polyamine concentrations in patients with renal failure. Hemodialysis (HD) may compensate for polyamine excretion; however, little is known about polyamine excretion. We measured whole-blood polyamine levels in patients on HD and examined the relationship between polyamine concentrations and indicators associated with health status. Study participants were 59 hemodialysis patients (median age: 70.0 years) at Minami-Uonuma City Hospital and 26 healthy volunteers (median age: 44.5 years). Whole-blood spermidine levels were higher and spermine/spermidine ratio (SPM/SPD) was lower in hemodialysis patients. Hemodialysis showed SPD efflux into the dialysate; however, blood polyamine levels were not altered by hemodialysis and appeared to be minimally excreted. The skeletal muscle mass index (SMI), which was positively correlated with hand grip strength and serum albumin level, was positively correlated with SPM/SPD. Given that sarcopenia and low serum albumin levels are reported risk factors for poor prognosis in HD patients, whole blood SPM/SPD in hemodialysis patients may be a new indicator of the prognosis and health status of HD patients.

Utility of the Global Leadership Initiative on Malnutrition criteria for the nutritional assessment of patients with end-stage renal disease receiving chronic hemodialysis

BACKGROUND

Malnutrition is associated with adverse outcomes in patients on chronic haemodialysis. Thus, identifying accurate methods for diagnosing malnutrition is essential. The present retrospective study investigated the utility of the new Global Leadership Initiative on Malnutrition (GLIM) criteria in patients undergoing chronic haemodialysis.

METHODS

Phase angle and fat-free mass index (FFMI) were derived using bioelectrical impedance analysis. Malnutrition was determined when the subjects had at least one phenotypic criterion (weight loss, low body mass index [BMI] or FFMI).

RESULTS

This study included 103 patients undergoing chronic haemodialysis and 46 (44.7%) patients were diagnosed as malnourished. Malnutrition determined using the GLIM criteria was associated with increased risks of all-cause death (hazard ratio = 3.0, p = 0.044) and infection requiring hospitalisation (hazard ratio = 2.4, p = 0.015), independent of age, sex and comorbidities. However, malnutrition was not related to major adverse cardiovascular events (p = 0.908). We further evaluated the longitudinal changes in phenotypic parameters. Subjects with median levels of high-sensitivity C-reactive protein exceeding 5 mg L^-1 exhibited decreased body weight and BMI (p = 0.015 and 0.016, respectively). In addition, body weight, BMI and FFMI were reduced in subjects with a median protein catabolic rate of < 1.0 mg kg^-1 day^-1 , even after adjustment for age, sex and comorbidities (p = 0.026, 0.053 and 0.039, respectively).

CONCLUSIONS

Malnutrition assessed using the GLIM criteria could be a useful predictor of mortality and infection in patients on chronic haemodialysis. To improve nutritional status, approaches for decreasing inflammation and increasing protein intake are needed.

Evaluation of Renal Impairment Influence on Metabolic Drug Clearance using a Modelling Approach

BACKGROUND AND OBJECTIVE

Chronic kidney disease (CKD) may alter drug renal elimination but is also known for interacting with hepatic metabolism via multiple uremic components. However, few global models, considering the five major cytochromes, have been published, and none specifically address the decrease in cytochrome P450 (CYP450) activity. The aim of our study was to estimate the possibility of quantifying residual cytochrome activity as a function of filtration rate, according to the data available in the literature.

METHODS

For each drug in the DDI-predictor database, we collected available pharmacokinetic data comparing drug exposition in the healthy patient and in various stages of CKD, before building a model capable of predicting the variation of exposure according to the degree of renal damage. We followed an In vivo Mechanistic Static Model (IMSM) approach, previously validated for predicting change in liver clearance. We estimated the remaining fraction parameters at glomerular filtration rate (GFR) = 0 and the alpha value of GFR to 50% impairment for the 5 major cytochromes using a non-linear constrained regression using Matlab software.

RESULTS

Thirty-one compounds had usable pharmacokinetic data, with 51 AUC ratios between healthy and renal impaired patients. The remaining CYP3A4 activity was estimated to be 0.4 when CYP2D6, 2C9, 2C19 and 1A2 activity was estimated to be 0.43; 1; 0.73 and 0.7, respectively. The alpha value was estimated to be at 6.62; 25; 9.8; 1.38 and 11.04 for each cytochrome. In comparison with published data, all estimates but one were correctly predicted in the range of 0.5-2.

CONCLUSION

Our approach was able to describe the impact of CKD on metabolic elimination. Modelling this process makes it possible to anticipate changes in clearance and drug exposure in CKD patients, with the advantage of greater simplicity than approaches based on physiologically-based pharmacokinetic modelling. However, a precise estimation of the impact of renal failure is not possible with an IMSM approach due to the large variability of the published data, and thus should rely on specific pharmacokinetic modelling for narrow therapeutic margin drugs.

The effect of high-dose vitamin D supplementation on hepcidin-25 and erythropoiesis in patients with chronic kidney disease

BACKGROUND

Hepcidin is considered to play a central role in the pathophysiology of renal anemia. Recent studies in healthy individuals have demonstrated a suppressive effect of vitamin D (VD) on the expression of hepcidin. In this post-hoc analysis based on a randomized controlled study, we evaluated the effect of supplementing chronic kidney disease (CKD) patients (stage G3-G4) with a high daily dose of native VD on serum levels of hepcidin-25, the hepcidin/ferritin ratio, as well as on markers of erythropoiesis.

METHODS

Patients with CKD stage G3-G4 included in a double blind, randomized, placebo (PBO) controlled study with available hepcidin measurements were analyzed. Study subjects received either 8000 international units (IU) of cholecalciferol daily or PBO for 12 weeks. We evaluated the change in markers of hepcidin expression, erythropoiesis, and iron status from baseline to week 12 and compared the change between the groups.

RESULTS

Eighty five patients completed the study. Calcitriol, but not 25-hydroxyvitamin D (25(OH) D), was inversely correlated with serum levels of hepcidin-25 (rho = -0,38; p =  < 0, 01 and rho = -0,02; p = 0, 89, respectively) at baseline. Supplementation with VD significantly raised the serum concentration of serum 25(OH)D in the treatment group (from 54 (39-71) to 156 (120-190) nmol/L; p =  < 0, 01)) but had no effect on any of the markers of hepcidin, erythropoiesis, or iron status in the entire cohort. However, we did observe an increase in hemoglobin (HB) levels and transferrin saturation (TSAT) as compared to the PBO group in a subgroup of patients with low baseline 25(OH)D levels (< 56 nmol/L). In contrast, in patients with high baseline 25(OH)D values (≥ 56 nmol/L), VD supplementation associated with a decrease in HB levels and TSAT (p = 0,056) within the VD group in addition to a decrease in hepcidin levels as compared to the PBO group.

CONCLUSION

High-dose VD supplementation had no discernible effect on markers of hepcidin or erythropoiesis in the entire study cohort. However, in patients with low baseline 25(OH)D levels, high-dose VD supplementation associated with beneficial effects on erythropoiesis and iron availability. In contrast, in patients with elevated baseline 25(OH)D levels, high-dose VD supplementation resulted in a decrease in hepcidin levels, most likely due to a deterioration in iron status.

Implication of changes in xanthine oxidase activity following hemodialysis

BACKGROUND

Xanthine oxidase activity has a key role in the development of oxidative stress and progression of cardiovascular diseases. However, the change of xanthine oxidase activity following hemodialysis and its prognostic impact remain uncertain.

METHODS

We prospectively included hemodialysis patients who did not take any anti-hyperuricemic agents and measured their xanthine oxidase activity before and after the index hemodialysis. The impact of change in xanthine oxidase activity during hemodialysis on cardiovascular death were investigated.

RESULTS

A total of 46 patients (median 72 years old, 29 men) were included. During hemodialysis, a common logarithm of xanthine oxidase activity decreased significantly from 1.16 (0.94, 1.27) to 1.03 (0.80, 1.20) (p < 0.01). Of them, xanthine oxidase activity remained unchanged or increased in 16 patients, who had a greater decrease in blood pressure and more hemoconcentration compared with others. Two-year survival from cardiovascular death was not significantly stratified by the changes in xanthine oxidase activity (p = 0.43).

CONCLUSIONS

During hemodialysis, xanthine oxidase activity decreased among the overall cohort, whereas some patients experienced its increases, which might be associated with hypotension and hemoconcentration during hemodialysis. Further larger-scale studies are required to validate our findings and find clinical implication of change in xanthine oxidase activity during hemodialysis.

N-Acetylcysteine: more than preventing contrast-induced nephropathy in uremic patients-focus on the antioxidant and anti-inflammatory properties

Oxidative stress (OS) has been recognized as a pathophysiologic mechanism underlying the development and progression of chronic kidney disease (CKD). OS, which results from the disturbance of balance among pro-oxidants and antioxidants favoring the pro-oxidants, is present even in early CKD and increases progressively along with deterioration of kidney function to end-stage kidney disease (ESKD). In ESKD, OS is further exacerbated mainly due to dialysis procedures per se and predisposes to increased cardiovascular morbidity and mortality. Therefore, since OS plays a pivotal role in the pathogenesis and progression of atherosclerosis in uremic patients, several strategies aiming to ameliorate OS in these patients have been proposed. Among those, N-acetylcysteine (NAC), a thiol-containing antioxidant agent, has attracted special attention due to its pleiotropic functions and beneficial effect in various OS-related entities including paracetamol overdose and prevention of contrast-induced nephropathy. In this review, we present the currently available literature on the antioxidant and anti-inflammatory properties of NAC in CKD, including hemodialysis and peritoneal dialysis.

Nutritional status, symptom burden, and predictive validity of the Pt-Global web tool/PG-SGA in CKD patients: A hospital based cross sectional study

BACKGROUND

Despite not being frequently recognized, malnutrition, a consequence of chronic kidney disease, negatively affects morbidity, mortality, functional activity, and patient's quality of life. Management of this condition is made more difficult by the dearth of knowledge regarding the symptom burden brought on by inadequate nutritional status. Additionally, there are multiple tools to evaluate nutritional status in CKD; but, Pt-Global web tool/PG-SGA used in oncology, has not been investigated in chronic kidney disease patients. This study aimed to explore the nutritional status, symptom burden and also investigate the predictive validity of Pt-Global web tool/PG-SGA among pre-dialysis diabetic and non-diabetic chronic kidney disease patients.

METHODOLOGY

This cross-sectional study was carried out at a renal clinic of a tertiary care public teaching hospital. Nutritional status and symptom burden was evaluated by employing a 'Pt-Global web tool/PG-SGA' which is considered as a preeminent interdisciplinary tool in oncology and other chronic catabolic conditions. The predictive validity of the Pt-Global web tool/PG-SGA, referred as overall score for malnutrition was ascertained using Receiver Operating Curves (ROC). The conclusions were drawn using descriptive statistics, correlation, and regression analysis.

RESULTS

In a sample of 450 pre-dialysis CKD patients, the malnutrition was present in 292(64.9%) patients. Diabetic CKD patients exhibit higher proportion of malnutrition 159(35.3%). The prevalence of malnutrition was exacerbated by eGFR reduction. The overall Pt-Global web tool/PGA-SGA score was significantly influenced by the symptoms of fatigue (81.5%), appetite loss (54.8%), physical pain (45.3%), constipation (31.78%), dry mouth (26.2%), and feeling full quickly (25.8%). The ROC analysis showed that the AUC for the total PG-SGA score was 0.988 (95% CI: 0.976-1.000), indicating that it is a reliable indicator of malnutrition. The sensitivity (84.2%) for identifying malnutrition was low when using the conventional tool cut off score of ≥9. Instead, it was discovered that a score of ≥3 had a greater sensitivity (99.3%) and specificity (44.3%) and was therefore recommended.

CONCLUSIONS

This study not only presents empirical evidence of poor nutritional status in CKD patients but also reveals that it is worse in patients with diabetes, hypoalbuminemia, and poorer kidney function (well recognized risk factors for cardiovascular disease). Early diagnosis and management of symptoms contributing malnutrition will reduce mortality and CKD progression. The Pt-Global web tool/PG-SGA total score of 3 or more appears to be the ideal cut off score for identifying malnutrition, which can be utilized by dietician for improving malnutrition.

Central obesity as assessed by conicity index and a-body shape index associates with cardiovascular risk factors and mortality in kidney failure patients

Background

Anthropometric indices of central obesity, waist circumference (WC), conicity index (CI), and a-body shape index (ABSI), are prognostic indicators of cardiovascular (CV) risk. The association of CI and ABSI with other CV risk indices, markers of nutritional status and inflammation, and clinical outcomes in chronic kidney disease (CKD) stage 5 (CKD5) patients was investigated.

Methods

In a cross-sectional study with longitudinal follow up of 203 clinically stable patients with CKD5 (median age 56 years; 68% males, 17% diabetics, 22% with CV disease, and 39% malnourished), we investigated CI and ABSI and their associations with atherogenic index of plasma (AIP), Framingham CV risk score (FRS), Agatston scoring of coronary artery calcium (CAC) and aortic valve calcium (AVC), handgrip strength (HGS), high sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6). CV events (CVE) and all-cause mortality during up to 10-years follow up were analyzed by multivariate survival analysis of restricted mean survival time (RMST).

Results

Chronic kidney disease patients with middle and highest CI and ABSI tertiles (indicating greater abdominal fat deposition), compared to those with the lowest CI and ABSI tertiles, tended to be older, more often men and diabetic, had significantly higher levels of hsCRP, IL-6, AIP, FRS, CAC and AVC scores. CI and ABSI were positively correlated with CAC, FRS, AIP, hsCRP and IL-6. Both CI and ABSI were negatively correlated with HGS. In age-weighted survival analysis, higher CI and ABSI were associated with higher risk of CVE (Wald test = 4.92, p = 0.027; Wald test = 4.95, p = 0.026, respectively) and all-cause mortality (Wald test = 5.24, p = 0.022; Wald test = 5.19, p = 0.023, respectively). In RMST analysis, low vs. high and middle tertiles of CI and ABSI associated with prolonged CVE-free time and death-free time, and these differences between groups increased over time.

Conclusion

Abdominal fat deposit indices, CI and ABSI, predicted CV outcomes and all-cause mortality, and were significantly associated with the inflammatory status in CKD patients.

New mechanisms involved in the development of cardiovascular disease in chronic kidney disease

Chronic kidney disease (CKD) is a pathology with a high worldwide incidence and an upward trend affecting the elderly. When CKD is very advanced, the use of renal replacement therapies is required to prolong its life (dialysis or kidney transplantation). Although dialysis improves many complications of CKD, the disease does not reverse completely. These patients present an increase in oxidative stress, chronic inflammation and the release of extracellular vesicles (EVs), which cause endothelial damage and the development of different cardiovascular diseases (CVD). CKD patients develop premature diseases associated with advanced age, such as CVD. EVs play an essential role in developing CVD in patients with CKD since their number increases in plasma and their content is modified. The EVs of patients with CKD cause endothelial dysfunction, senescence and vascular calcification. In addition, miRNAs free or transported in EVs together with other components carried in these EVs promote endothelial dysfunction, thrombotic and vascular calcification in CKD, among other effects. This review describes the classic factors and focuses on the role of new mechanisms involved in the development of CVD associated with CKD, emphasizing the role of EVs in the development of cardiovascular pathologies in the context of CKD. Moreover, the review summarized the EVs' role as diagnostic and therapeutic tools, acting on EV release or content to avoid the development of CVD in CKD patients.