Mitochondrial calcium uniporter promotes kidney aging in mice through inducing mitochondrial calcium-mediated renal tubular cell senescence

Renal tubular epithelial cell senescence plays a critical role in promoting and accelerating kidney aging and age-related renal fibrosis. Senescent cells not only lose their self-repair ability, but also can transform into senescence-associated secretory phenotype (SASP) to trigger inflammation and fibrogenesis. Recent studies show that mitochondrial dysfunction is critical for renal tubular cell senescence and kidney aging, and calcium overload and abnormal calcium-dependent kinase activities are involved in mitochondrial dysfunction-associated senescence. In this study we investigated the role of mitochondrial calcium overload and mitochondrial calcium uniporter (MCU) in kidney aging. By comparing the kidney of 2- and 24-month-old mice, we found calcium overload in renal tubular cells of aged kidney, accompanied by significantly elevated expression of MCU. In human proximal renal tubular cell line HK-2, pretreatment with MCU agonist spermine (10 μM) significantly increased mitochondrial calcium accumulation, and induced the production of reactive oxygen species (ROS), leading to renal tubular cell senescence and age-related kidney fibrosis. On the contrary, pretreatment with MCU antagonist RU360 (10 μM) or calcium chelator BAPTA-AM (10 μM) diminished D-gal-induced ROS generation, restored mitochondrial homeostasis, retarded cell senescence, and protected against kidney aging in HK-2 cells. In a D-gal-induced accelerated aging mice model, administration of BAPTA (100 μg/kg. i.p.) every other day for 8 weeks significantly alleviated renal tubuarl cell senescence and fibrosis. We conclude that MCU plays a key role in promoting renal tubular cell senescence and kidney aging. Targeting inhibition on MCU provides a new insight into the therapeutic strategy against kidney aging.

Frailty, but not cognitive impairment, improves mortality risk prediction among those with chronic kidney disease-a nationally representative study

BACKGROUND

Though older adults with chronic kidney disease (CKD) have a greater mortality risk than those without CKD, traditional risk factors poorly predict mortality in this population. Therefore, we tested our hypothesis that two common geriatric risk factors, frailty and cognitive impairment, and their co-occurrence, might improve mortality risk prediction in CKD.

METHODS

Among participants aged ≥ 60 years from National Health and Nutrition Examination Survey (2011-2014), we quantified associations between frailty (physical frailty phenotype) and global/domain-specific cognitive function (immediate-recall [CERAD-WL], delayed-recall [CERAD-DL], verbal fluency [AF], executive function/processing speed [DSST], and global [standardized-average of 4 domain-specific tests]) using linear regression, and tested whether associations differed by CKD using a Wald test. We then tested whether frailty, global cognitive impairment (1.5SD below the mean), or their combination improved prediction of mortality (Cox models, c-statistics) compared to base models (likelihood-ratios) among those with and without CKD.

RESULTS

Among 3,211 participants, 1.4% were cognitively impaired, and 10.0% were frail; frailty and cognitive impairment co-occurrence was greater among those with CKD versus those without (1.2%vs.0.1%). Frailty was associated with worse global cognitive function (Cohen's d = -0.26SD,95%CI -0.36,-0.17), and worse cognitive function across all domains; these associations did not differ by CKD (pinteractions > 0.05). Mortality risk prediction improved only among those with CKD when accounting for frailty (p[likelihood ratio test] < 0.001) but not cognitive impairment.

CONCLUSIONS

Frailty is associated with worse cognitive function regardless of CKD status. While CKD and frailty improved mortality prediction, cognitive impairment did not. Risk prediction tools should incorporate frailty to improve mortality prediction among those with CKD.

Associations between long-term exposure to air pollution and kidney function utilizing electronic healthcare records: a cross-sectional study

BACKGROUND

Chronic kidney disease (CKD) affects more than 38 million people in the United States, predominantly those over 65 years of age. While CKD etiology is complex, recent research suggests associations with environmental exposures.

METHODS

Our primary objective is to examine creatinine-based estimated glomerular filtration rate (eGFRcr) and diagnosis of CKD and potential associations with fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) using a random sample of North Carolina electronic healthcare records (EHRs) from 2004 to 2016. We estimated eGFRcr using the serum creatinine-based 2021 CKD-EPI equation. PM2.5 and NO2 data come from a hybrid model using 1 km2 grids and O3 data from 12 km2 CMAQ grids. Exposure concentrations were 1-year averages. We used linear mixed models to estimate eGFRcr per IQR increase of pollutants. We used multiple logistic regression to estimate associations between pollutants and first appearance of CKD. We adjusted for patient sex, race, age, comorbidities, temporality, and 2010 census block group variables.

RESULTS

We found 44,872 serum creatinine measurements among 7,722 patients. An IQR increase in PM2.5 was associated with a 1.63 mL/min/1.73m2 (95% CI: -1.96, -1.31) reduction in eGFRcr, with O3 and NO2 showing positive associations. There were 1,015 patients identified with CKD through e-phenotyping and ICD codes. None of the environmental exposures were positively associated with a first-time measure of eGFRcr < 60 mL/min/1.73m2. NO2 was inversely associated with a first-time diagnosis of CKD with aOR of 0.77 (95% CI: 0.66, 0.90).

CONCLUSIONS

One-year average PM2.5 was associated with reduced eGFRcr, while O3 and NO2 were inversely associated. Neither PM2.5 or O3 were associated with a first-time identification of CKD, NO2 was inversely associated. We recommend future research examining the relationship between air pollution and impaired renal function.

Association between systemic immune-inflammation index and chronic kidney disease: A population-based study

BACKGROUND

Systemic immune-inflammation index (SII) is a new indicator of inflammation, and chronic kidney disease (CKD) has a connection to inflammation. However, the relationship between SII and CKD is still unsure. The aim of this study was whether there is an association between SII and CKD in the adult US population.

METHODS

Data were from the National Health and Nutrition Examination Survey (NHANES) in 2003-2018, and multivariate logistic regression was used to explore the independent linear association between SII and CKD. Smoothing curves and threshold effect analyses were utilized to describe the nonlinear association between SII and CKD.

RESULTS

The analysis comprised 40,660 adults in total. After adjusting for a number of factors, we found a positive association between SII and CKD [1.06 (1.04, 1.07)]. In subgroup analysis and interaction tests, this positive correlation showed differences in the age, hypertension, and diabetes strata (p for interaction<0.05), but remained constant in the sex, BMI, abdominal obesity, smoking, and alcohol consumption strata. Smoothing curve fitting revealed a non-linear positive correlation between SII and CKD. Threshold analysis revealed a saturation effect of SII at the inflection point of 2100 (1,000 cells/μl). When SII < 2100 (1,000 cells/μl), SII was an independent risk element for CKD.

CONCLUSIONS

In the adult US population, our study found a positive association between SII and CKD (inflection point: 2100). The SII can be considered a positive indicator to identify CKD promptly and guide therapy.

Prosthetic brachial artery-external jugular vein arteriovenous grafts as a novel option for hemodialysis access: A case report

Following the exhaustion of all conventional hemodialysis access options in the upper extremities, a prosthetic arteriovenous loop was performed between the brachial artery (BA) and the external jugular vein (EJV) as a novel access option for hemodialysis in the present case report. During the procedure, a polytetrafluoroethylene graft was anastomosed to the BA and the EJV, and looped on the upper limb. The safety and reliability of BA-EJV access was evaluated by determining the complications, patency and intervention rates. The patient was then followed up for 20 months. The graft became thrombosed 20 months after the placement. There were no complications, such as infection, bleeding or aneurysmal lesions. Overall, the present study demonstrates that hemodialysis via BA-EJV access represents an unusual, yet effective and safe procedure, which may be conducted with acceptable complications and patency rates.

Severe Anemia from Multiple Gastric Hyperplastic Polyps in a Hemodialysis Patient after Long-term Use of a Proton-pump Inhibitor

A 90-year-old man on maintenance hemodialysis was admitted due to severe symptomatic anemia. Biopsies under esophagogastroduodenoscopy demonstrated that the cause of anemia was intermittent blood oozing from multiple gastric hyperplastic polyps. Even after successful eradication of Helicobacter pylori, he showed hypergastrinemia (480 pg/mL) owing to esomeprazole (proton-pump inhibitor) therapy for the past 4.5 years to treat reflux esophagitis. Seven months after we switched esomeprazole to famotidine (H2-receptor antagonist), those gastric polyps and anemia were remarkably ameliorated with lowered gastrin levels. This case indicates that long-term use of a proton-pump inhibitor triggers chronic hypergastrinemia, leading to gastric hyperplastic polyps and subsequent severe anemia.

Efficacy and Safety of Ferric Citrate on Hyperphosphatemia among Chinese Patients with Chronic Kidney Disease Undergoing Hemodialysis: A Phase III Multicenter Randomized Open-Label Active-Drug-Controlled Study

INTRODUCTION

Hyperphosphatemia in chronic kidney disease (CKD) patients is positively associated with mortality. Ferric citrate is a potent phosphorus binder that lowers serum phosphorus level and improves iron metabolism. We compared its efficacy and safety with active drugs in Chinese CKD patients with hemodialysis.

METHODS

Chinese patients undergoing hemodialysis were randomized into two treatment groups in a 1:1 ratio, receiving either ferric citrate or sevelamer carbonate, respectively, for 12 weeks. Serum phosphorus levels, calcium concentration, and iron metabolism parameters were evaluated every 2 weeks. Frequency and severity of adverse events were recorded.

RESULTS

217 (90.4%) patients completed the study with balanced demographic and baseline characteristics between two groups. Ferric citrate decreased the serum phosphorus level to 0.59 ± 0.54 mmol/L, comparable to 0.56 ± 0.62 mmol/L by sevelamer carbonate. There was no significant difference between two groups (p > 0.05) in the proportion of patients with serum phosphorus levels reaching the target range, the response rate to the study drug, and the changes of corrected serum calcium concentrations, and intact-PTH levels at the end of treatment. The change of iron metabolism indicators in the ferric citrate group was significantly higher than those in the sevelamer carbonate group. There are 47 (40.5%) patients in the ferric citrate group, and 26 (21.3%) patients in the sevelamer carbonate group experienced drug-related treatment emergent adverse events (TEAEs); most were mild and tolerable. Common drug-related TEAEs were gastrointestinal disorders, including diarrhea (12.9 vs. 2.5%), fecal discoloration (14.7 vs. 0%), and constipation (1.7 vs. 7.4%) in ferric citrate and sevelamer carbonate group.

CONCLUSION

Ferric citrate capsules have good efficacy and safety in the control of hyperphosphatemia in adult patients with CKD undergoing hemodialysis. Efficacy is not inferior to sevelamer carbonate. The TEAEs were mostly mild and tolerated by the patients.

Urgent Implantation of Peritoneal Dialysis Catheter in Chronic Kidney Disease and Acute Kidney Injury-A Review

Acute kidney injury (AKI) and sudden exacerbation of chronic kidney disease (CKD) frequently necessitate urgent kidney replacement therapy (UKRT). Peritoneal dialysis (PD) is recognized as a viable modality for managing such patients. Urgent-start peritoneal dialysis (USPD) may be associated with an increased number of complications and is rarely utilized. This review examines recent literature investigating the clinical outcomes of USPD in CKD and AKI. Relevant research was identified through searches of the MEDLINE (PubMed), Scopus, Web of Science, and Google Scholar databases using MeSH terms and relevant keywords. Included studies focused on the emergency use of peritoneal dialysis in CKD or AKI and reported treatment outcomes. While no official recommendations exist for catheter implantation in USPD, the impact of the technique itself on outcomes was found to be less significant compared with the post-implantation factors. USPD represents a safe and effective treatment modality for AKI, although complications such as catheter malfunctions, leakage, and peritonitis were observed. Furthermore, USPD demonstrated efficacy in managing CKD, although it was associated with a higher incidence of complications compared to conventional-start peritoneal dialysis. Despite its cost-effectiveness, PD requires greater technical expertise from medical professionals. Close supervision and pre-planning for catheter insertion are essential for CKD patients. Whenever feasible, an urgent start should be avoided. Nevertheless, in emergency scenarios, USPD does remain a safe and efficient approach.

Inhibiting NLRP3 signaling in aging podocytes improves their life- and health-span

The decrease in the podocyte's lifespan and health-span that typify healthy kidney aging cause a decrease in their normal structure, physiology and function. The ability to halt and even reverse these changes becomes clinically relevant when disease is superimposed on an aged kidney. RNA-sequencing of podocytes from middle-aged mice showed an inflammatory phenotype with increases in the NLRP3 inflammasome, signaling for IL2/Stat5, IL6 and TNF, interferon gamma response, allograft rejection and complement, consistent with inflammaging. Furthermore, injury-induced NLRP3 signaling in podocytes was further augmented in aged mice compared to young ones. The NLRP3 inflammasome (NLRP3, Caspase-1, IL1β IL-18) was also increased in podocytes of middle-aged humans. Higher transcript expression for NLRP3 in human glomeruli was accompanied by reduced podocyte density and increased global glomerulosclerosis and glomerular volume. Pharmacological inhibition of NLRP3 with MCC950, or gene deletion, reduced podocyte senescence and the genes typifying aging in middle-aged mice, which was accompanied by an improved podocyte lifespan and health-span. Moreover, modeling the injury-dependent increase in NLRP3 signaling in human kidney organoids confirmed the anti-senescence effect of MC9950. Finally, NLRP3 also impacted liver aging. Together, these results suggest a critical role for the NLRP3 inflammasome in podocyte and liver aging.

A nomogram for predicting the 4-year risk of chronic kidney disease among Chinese elderly adults

BACKGROUND

Chronic kidney disease (CKD) has become a major public health problem across the globe, leading to various complications. This study aimed to construct a nomogram to predict the 4-year risk of CKD among Chinese adults.

METHODS

The study was based on the China Health and Retirement Longitudinal Study (CHARLS). A total of 3562 participants with complete information in CHARLS2011 and CHARLS2015 were included, and further divided into the training cohort and the validation cohort by a ratio of 7:3. Univariate and multivariate logistic regression analyses were used to select variables of the nomogram. The nomogram was evaluated by receiver-operating characteristic curve, calibration plots, and decision curve analysis (DCA).

RESULTS

In all, 2494 and 1068 participants were included in the training cohort and the validation cohort, respectively. A total of 413 participants developed CKD in the following 4 years. Five variables selected by multivariate logistic regression were incorporated in the nomogram, consisting of gender, hypertension, the estimated glomerular filtration rate (eGFR), hemoglobin, and Cystatin C. The area under curve was 0.809 and 0.837 in the training cohort and the validation cohort, respectively. The calibration plots showed agreement between the nomogram-predicted probability and the observed probability. DCA indicated that the nomogram had potential clinical use.

CONCLUSIONS

A predictive nomogram was established and internally validated in aid of identifying individuals at increased risk of CKD.

Anticoagulation for Stroke Prevention of Concomitant Atrial Fibrillation and End-Stage Renal Disease: Insights of Cardiologists and Nephrologists From India

Introduction Patients with concomitant atrial fibrillation (AF) and end-stage renal disease (ESRD) are at increased risk of thrombosis and bleeding. Diligent anticoagulant therapy that prevents major bleeding is essential for stroke prevention. There is a dearth of evidence and guidance on anticoagulation in this patient subset. Methods A validated questionnaire was sent to 500 physicians across India. Anonymized responses from 353 consenting physicians (275 cardiologists and 78 nephrologists) were analyzed. Results Most physicians opined that the risk of progression of chronic kidney disease (CKD) stages 2-4 to ESRD was 1-5%, and that >10% of patients with ESRD had concomitant AF. Most physicians perceived that the risk of ischemic stroke, major bleeding, and mortality was 30-40%, <15%, and >40% respectively in patients with concomitant AF and ESRD. The first critical goal for the management of these patients was 'reduction of thrombotic risk', followed by 'prevention of bleeding' and finally 'prevention of ESRD progression' (72.0%, 68.0%, and 67.1% participants, respectively). Most participating physicians (93.8%) preferred non-vitamin K antagonist oral anticoagulants (NOACs) over warfarin for stroke prevention, and most of the participating physicians (94.9%) preferred an adjusted dose rather than the standard dose of the NOAC. Most of the responses were similar between cardiologists and nephrologists. Conclusion According to the survey response, patients with concomitant AF and ESRD have an increased risk of thrombosis, bleeding, and mortality. NOACs with dose adjustment are the preferred modality for stroke prevention among cardiologists and nephrologists in India, with the primary goal of preventing thrombotic events.

Clin-Star corner: What is new at the interface of geriatrics and nephrology?

Chronic kidney disease (CKD) is prevalent and burdensome among older adults in the United States. CKD affects at least 15% of the US population, and adults over 65 comprise the largest subset within this group. In this special article, we highlight key findings of three recent original investigations in nephrology and describe each study, relevance to the care of older adults, and current areas of uncertainty that warrant further investigation. Articles relate to removal of the race adjustment in the estimation of kidney function, the use of novel therapeutics to halt CKD progression and improve cardiovascular outcomes, and medication management for short-term pain control in CKD.

Assessing the efficacy of coproduction to better understand the barriers to achieving sustainability in NHS chronic kidney services and create alternate pathways

CONTEXT

Too many people living with chronic kidney disease are opting for and starting on hospital-based dialysis compared to a home-based kidney replacement therapy. Dialysis services are becoming financially unsustainable.

OBJECTIVE

This study aimed to assess the efficacy of coproductive research in chronic kidney disease service improvement to achieve greater sustainability.

DESIGN

A 2-year coproductive service improvement study was conducted with multiple stakeholders with the specific intention of maximizing engagement with the national health kidney services, patients and public.

SETTING AND PARTICIPANTS

A national health kidney service (3 health boards, 18 dialysis units), patients and families (n = 50), multidisciplinary teams including doctors, nurses, psychologists, social workers, and so forth (n = 68), kidney charities, independent dialysis service providers and wider social services were part of this study.

FINDINGS

Coproductive research identified underutilized resources (e.g., patients on home dialysis and social services) and their potential, highlighted unmet social care needs for patients and families and informed service redesign. Education packages were reimagined to support the home dialysis agenda including opportunities for wider service input. The impacts of one size fits all approaches to dialysis on specialist workforce skills were made clearer and also professional, patient and public perceptions of key sustainability policies.

DISCUSSION AND CONCLUSIONS

Patient and key stakeholders mapped out new ways to link services to create more sustainable models of kidney health and social care. Maintaining principles of knowledge coproduction could help achieve financial sustainability and move towards more prudent adult chronic kidney disease services.

PATIENT OR PUBLIC CONTRIBUTION

Involved in developing research questions, study design, management and conduct, interpretation of evidence and dissemination.

Application of a Novel Biosensor for Salivary Conductivity in Detecting Chronic Kidney Disease

The prevalence of chronic kidney disease (CKD) is increasing, and it brings an enormous healthcare burden. The traditional measurement of kidney function needs invasive blood tests, which hinders the early detection and causes low awareness of CKD. We recently designed a device with miniaturized coplanar biosensing probes for measuring salivary conductivity at an extremely low volume (50 μL). Our preliminary data discovered that the salivary conductivity was significantly higher in the CKD patients. This cross-sectional study aims to validate the relationship between salivary conductivity and kidney function, represented by the estimated glomerular filtration rate (eGFR). We enrolled 214 adult participants with a mean age of 63.96 ± 13.53 years, of whom 33.2% were male. The prevalence rate of CKD, defined as eGFR < 60 mL/min/1.73 m2, is 11.2% in our study. By multivariate linear regression analyses, we found that salivary conductivity was positively related to age and fasting glucose but negatively associated with eGFR. We further divided subjects into low, medium, and high groups according to the tertials of salivary conductivity levels. There was a significant trend for an increment of CKD patients from low to high salivary conductivity groups (4.2% vs. 12.5% vs. 16.9%, p for trend: 0.016). The receiver operating characteristic (ROC) curves disclosed an excellent performance by using salivary conductivity combined with age, gender, and body weight to diagnose CKD (AUC equal to 0.8). The adjusted odds ratio of CKD is 2.66 (95% CI, 1.10−6.46) in subjects with high salivary conductivity levels. Overall, salivary conductivity can serve as a good surrogate marker of kidney function; this real-time, non-invasive, and easy-to-use portable biosensing device may be a reliable tool for screening CKD.

Nephrologist referrals of elderly CKD patients in Singapore: A cross-sectional study

Background

Chronic kidney disease (CKD) is common in the elderly population. By 2035, approximately one-quarter of Singapore residents are expected to have CKD. Many of these patients are not referred to nephrologists.

Aim

We aimed to compare the characteristics of elderly (≥ 65 years old) patients with stage 3B CKD and above in the referral and non-referral groups.

Design and settings

A cross-sectional study in the primary care organisation National University Polyclinics (NUP), Singapore.

Method

Retrospective data were extracted from the electronic health records of CKD patients (≥ 65 years old) with stage 3B CKD and above.

Results

From 1 January to 31 December 2018, a total of 1,536 patients aged 65 years or older were diagnosed with stage 3B CKD or above (non-referral group =1,179 vs. referral group =357). The mean patient age in the non-referral group (78.3 years) was older than that in the referral group (75.9 years) (P<0.001). Indian elderly patients were referred more compared to their Chinese counterparts (P=0.008). The non-referral group was prescribed significantly less fibrate, statins, insulin, sulfonylureas, dipeptidyl peptidase-4 inhibitors, and antiplatelet than the referral group (P<0.05), but only the difference in fibrates remained significant on subsequent multivariate analysis.

Conclusions

This study demonstrates that there is a considerable number of elderly CKD patients exclusively managed in the primary care setting (n = 1,179) and that referrals primarily depend on demographic factors, namely age and ethnicity, rather than medical determinants of CKD severity or case complexity.

Biotic Supplements in Patients With Chronic Kidney Disease: Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Gut flora imbalance characterizes patients with chronic kidney disease (CKD). Although biotic supplementation has been proposed to lessen inflammation and oxidative stress and, thus, reduce the risk of progressive kidney damage and cardiovascular disease, the effects remain controversial. We conducted a meta-analysis to assess the therapeutic benefits of biotics in CKD.

METHODS

PubMed, Embase, and Cochrane databases were systematically searched for randomized controlled trials that evaluated any biotic (prebiotic, probiotic, synbiotics) supplements in patients with CKD (CKD, stage 3-4 to end-stage renal disease). Primary endpoints included changes in renal function, markers of inflammation, and oxidative stress. Secondary endpoints included changes in levels of uremic toxins and variations in lipid metabolism.

RESULTS

Twenty-three eligible studies included 842 participants. In a pooled-analysis, biotics did not change estimated glomerular filtration rate (mean difference [MD] = 0.08, P = .92) or serum albumin (MD = -0.01, P = .86), although prebiotics reduced serum creatinine (standardized mean difference [SMD] = -0.23, P = .009) and blood urea nitrogen (MD = -6.05, P < .00001). Biotics improved total antioxidative capacity (SMD = 0.37, P = .007) and malondialdehyde (SMD = -0.96, P = .006) and reduced the inflammatory marker interleukin-6 (SMD = -0.30, P = .01) although not C-reactive protein (SMD = -0.22, P = .20). Biotic intervention reduced some uremic toxins, including p-cresol sulfate (SMD = -2.18, P < .0001) and indoxyl sulfate (MD = -5.14, P = .0009), which decreased in dialysis-dependent patients. Another toxin, indole-3-acetic acid (MD = -0.22, P = .63), did not change. Lipids were unaffected by biotic intervention (total cholesterol: SMD = -0.01, P = .89; high-density lipoprotein: SMD = -0.08, P = .76; low-density lipoprotein: MD = 3.54, P = .28; triglyceride: MD = -2.26, P = .58).

CONCLUSION

The results highlight the favorable influence of biotics on circulating markers of creatinine, oxidant stress (malondialdehyde, total antioxidative capacity), inflammation (interleukin-6), and uremic toxins (p-cresol sulfate) in patients with CKD. Biotics did not affect estimated glomerular filtration rate, albumin, indole-3-acetic acid, or lipids in either predialysis or dialysis patients.

Effects of Helichrysum Psudoplicatum supplementation on pruritus intensity, fatigue, quality of life and anorexia in hemodialysis patients: a randomized, double-blind placebo-controlled trial

OBJECTIVES

Anorexia, fatigue and pruritus are common complications of hemodialysis (HD) patients. Today, the use of medicinal plants is more than synthetic drugs due to their safety. Therefore, we designed a randomized controlled clinical trial to evaluate the effects of Helichrysum psudoplicatum (H. psudoplicatum) supplementation on biochemical parameters, pruritus intensity, fatigue, quality of life and anorexia in HD patients.

METHODS

This randomized, double-blind, placebo-controlled trial was performed on 50 subjects with, aged 55-65 years old. HD patients were randomly divided into two groups. Intervention group received 250 mg/day of H. psudoplicatum supplement capsule for 6 weeks (n=25), and the placebo group was given placebo capsule for the same time duration and dosage (n=25). The serum concentrations of urea, creatinine, albumin and hemoglobin were measured enzymatically methods. Anorexia, pruritus intensity, quality of life the dialysis patients with pruritus and fatigue score was measured using a Simplified Nutritional Appetite Questionnaire (SNAQ), Numerical rating scale (NRS), Fatigue severity scale (FSS) and ItchyQoL questionnaire, respectively. Shapiro-Wilk and independent-samples t-test or Mann-Whitney test were used for the analysis of the data.

RESULTS

The results showed that the H. psudoplicatum supplementation significantly improved the pruritus intensity, quality of life the dialysis patients with pruritus and fatigue in HD patients, for 6 weeks (p<0.001). However, it did not significantly effect on the anorexia, albumin, hemoglobin, urea, creatinine, arm circumference, and body mass index (p>0.05).

CONCLUSIONS

According to the results of this study, H. psudoplicatum supplementation can be effective as an adjunct therapy to improve pruritus intensity, quality of life, fatigue and relative improvement of anorexia in HD patients.

Prevalence and risk factors of Hantavirus infection in patients undergoing hemodialysis in Khartoum, Sudan, in 2019: a cross-sectional study

BACKGROUND

Hantaviruses are enveloped negative sense RNA viruses that cause hemorrhagic fever with renal syndrome. This study aimed to identify the prevalence of Hantavirus IgG antibodies and possible risk factors for Hantaviruses infections among end-stage renal disease (ESRD) patients attending the Dr Salma dialysis center in Sudan.

METHODOLOGY

This was a cross-sectional study in which 91 ESRD patients and 30 healthy plasma samples were screened for Hantavirus IgG antibodies using ELISA. A questionnaire containing sociodemographics, history of rat exposure and clinical data information was filled in by each ESRD patient.

RESULTS

In this study, 9 out of 91 ESRD patients (9.9%) tested positive for Hantaviruses antibodies (IgG) while none of the 30 healthy plasma samples showed seropositivity. There was no statistically significant association between age, gender, educational level and rat exposure and Hantavirus infection in ESRD patients (p>0.05).

CONCLUSION

This study is the first to be conducted in Sudan regarding Hantaviruses and ESRD. The prevalence of Hantavirus antibodies among ESRD patients is high compared with findings reported in the literature from studies conducted on the same group of patients. It points to an interesting question as to whether Hantaviruses have an association with ESRD but further studies are needed before drawing any conclusions.

[Self-reported sleep and wake disorders in patients with ostheoarthrosis and end-stage renal disease]

OBJECTIVE

This study aimed to assess subjective sleep and wake disorders (SWD) in patients with osteoarthritis and comorbid end-stage renal disease (ESRD) receiving hemodialysis (ESRD-HD) compared to patients with osteoarthritis and without chronic kidney disease (CKD) as well as to clarify of the association of subjective sleep characteristics with the levels of anxiety and depression and pain, general health score and laboratory parameters in these cohorts.

MATERIAL AND METHODS

This pilot case-control study included the patients with stage III hip osteoarthritis with ESRD-HD (n=19) and without CKD (n=19) aged 18-85 years. The patients received the consultations of orthopedic surgeon and internal medicine specialist with anthropometry and clinical and biochemical blood tests. Subjective SWD were assessed with Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Fatigue Severity Scale (FSS), Insomnia Severity Index (ISI), diagnostic criteria for restless legs syndrome (RLS) and Berlin questionnaire. Anxiety and depression were assessed with Hospital Anxiety and Depression Scale (HADS) and Beck Depression Inventory (BDI). Subjective general health and osteoarthritis-related pain were assessed with visual analog scales (VAS).

RESULTS

Compared to the patients with osteoarthritis and without CKD, the patients with osteoarthritis and ESRD-HD had a lower VAS score for general health (50.00 (40.00-75.00) points and 80.00 (70.00-80.00) points, p=0.014), a higher PSQI (12.0 (8.5-14.5) points and 8.0 (6.0-11.0) points, p=0.046), a higher incidence of RLS (59% and 16.8%, p=0.017) and a lower level of anxiety according to HADS (0.0 (0.0-3.0) points and 3.0 (2.0-5.5) points, p=0.025). The correlation and regression analysis showed the association of PSQI score with VAS score for general health (b= -1.7 points, p=0.002 with adjustment for age, sex and ESRD-HD), as well as the association of SWD with laboratory markers (PSQI score with creatinine level, FSS with eosinophil count, RLS with creatinine, urea and potassium levels).

CONCLUSION

The results of our study demonstrated the high incidence of SWD in patients with osteoarthritis. These SWD have complex pathogenesis and require specific approach in patients with osteoarthritis and ESRD-HD.

Maternal and Infant Factors Influencing Human Milk Oligosaccharide Composition: Beyond Maternal Genetics

Maternal genetics is a key determinant of human milk oligosaccharide (HMO) composition in human milk. Beyond genetic status, other factors influencing the HMO profile are poorly defined. Thus, we aimed to review the existing evidence on the associations between nongenetic maternal and infant factors and HMO composition. A systematic search was performed on PubMed and Web of Science (without a time restriction) to identify any relevant studies published. In total, 1056 results were obtained, of which 29 articles were selected to be included in this review. The range of factors investigated include lactation stage, maternal pre-pregnancy BMI (ppBMI), maternal age, parity, maternal diet, mode of delivery, infant gestational age, and infant sex. The data suggest that, beyond maternal genetics, HMO composition seems to be influenced by all these factors, but the underlining mechanisms remain speculative. The published evidence is discussed in this review, along with potential implications for infant growth and development. For example, 2'-fucosyllactose, which was reportedly increased in mothers with higher ppBMIs, was also associated with increased infant weight and height. In addition, greater levels of sialylated HMOs after preterm birth may support brain development in these infants.

Application of mesenchymal stem cell-derived exosomes in kidney diseases

Kidney injury (KI) has high morbidity and mortality; there has been no ideal practical treatment available in clinical practice until now. Exosomes are formed from fusing multisubunit body membranes and are secreted into the extracellular matrix, intercellular communication membracusses. As a cell-free treatment, it offers a new approach to the treatment of KI. Exosomes are spherical vesicles with or no separator cup that shapes proteins, and RNA acts on the target cells through various means to promote tissue damage and mitigate apoptosis, both inflammation and oxidative stress. Exosomes derived from mesenchymal stem cells (MSC) have a paracrine function in promoting tissue repair and immune regulation. The MSC-Exos provide specific benefits over the MSCs. The urinary exosomes closely follow the functions and diseases of the kidneys. Though much of the research in this field is only at the preliminary stages, previous research has demonstrated that MSC-Exos damaged tissues to offer proteins, mRNAs, and microRNAs as remedies for kidney injury. Although exosomes' role in tissue repair is currently is greatly debated, several key issues remain unaddressed. This is a summarization of the work done concerning MSC in the treatment of KI.

Aging and Renal Disease: Old Questions for New Challenges

Chronic kidney disease (CKD) is a growing problem among aging population, and the number of individuals at risk of end stage renal disease is rising. Part of the reason lies in incomplete understanding of the pathways underlying renal aging and kidney disease, as well as insufficient delivery of evidence-based treatment to elderly patients with CKD. This review aims to address these unsolved issues by delineating updated mechanisms of renal senescence and summarizing recent findings on key clinical aspects of CKD in the elderly. Challenges and obstacles in caring for older people with CKD are discussed, with an emphasis on modification of risk factors, prevention of acute kidney injury, stabilization of progression and decision on dialysis initiation.

Prediction of Mortality in Hemodialysis Patients Using Moving Multivariate Distance

There is an increasingly widespread use of biomarkers in network physiology to evaluate an organism’s physiological state. A recent study showed that albumin variability increases before death in chronic hemodialysis patients. We hypothesized that a multivariate statistical approach would better allow us to capture signals of impending physiological collapse/death. We proposed a Moving Multivariate Distance (MMD), based on the Mahalanobis distance, to quantify the variability of the multivariate biomarker profile as a whole from one visit to the next. Biomarker profiles from a visit were used as the reference to calculate MMD at the subsequent visit. We selected 16 biomarkers (of which 11 are measured every 2 weeks) from blood samples of 763 chronic kidney disease patients hemodialyzed at the CHUS hospital in Quebec, who visited the hospital regularly (∼every 2 weeks) to perform routine blood tests. MMD tended to increase markedly preceding death, indicating an increasing intraindividual multivariate variability presaging a critical transition. In survival analysis, the hazard ratio between the 97.5th percentile and the 2.5th percentile of MMD reached as high as 21.1 [95% CI: 14.3, 31.2], showing that higher variability indicates substantially higher mortality risk. Multivariate approaches to early warning signs of critical transitions hold substantial clinical promise to identify early signs of critical transitions, such as risk of death in hemodialysis patients; future work should also explore whether the MMD approach works in other complex systems (i.e., ecosystems, economies), and should compare it to other multivariate approaches to quantify system variability.

Epidemiology of end-stage kidney disease

End-stage kidney disease (ESKD) is a common and morbid disease that affects patients' quality and length of life, representing a large portion of health care expenditure in the United States. These patients commonly have associated diabetes and cardiovascular disease, with high rates of cardiovascular-related death. Management of ESKD requires renal replacement therapy via dialysis or transplantation. While transplantation provides the greatest improvement in survival and quality of life, the vast majority of patients are treated initially with hemodialysis. However, outcomes differ significantly among patient populations. Barriers in access to care have particularly affected at-risk populations, such as Black and Hispanic patients. These patients receive less pre-ESKD nephrology care, are less likely to initiate dialysis with a fistula, and wait longer for transplants-even in pediatric populations. Priorities for ESKD care moving into the future include increasing access to nephrology care in underprivileged populations, providing patient-centered care based on each patient's "life plan," and focusing on team-based approaches to ESKD care. This review explores ESKD from the perspective of epidemiology, costs, vascular access, patient-reported outcomes, racial disparities, and the impact of the COVID-19 crisis.

Capillary Rarefaction in Obesity and Metabolic Diseases-Organ-Specificity and Possible Mechanisms

Obesity and its comorbidities like diabetes, hypertension and other cardiovascular disorders are the leading causes of death and disability worldwide. Metabolic diseases cause vascular dysfunction and loss of capillaries termed capillary rarefaction. Interestingly, obesity seems to affect capillary beds in an organ-specific manner, causing morphological and functional changes in some tissues but not in others. Accordingly, treatment strategies targeting capillary rarefaction result in distinct outcomes depending on the organ. In recent years, organ-specific vasculature and endothelial heterogeneity have been in the spotlight in the field of vascular biology since specialized vascular systems have been shown to contribute to organ function by secreting varying autocrine and paracrine factors and by providing niches for stem cells. This review summarizes the recent literature covering studies on organ-specific capillary rarefaction observed in obesity and metabolic diseases and explores the underlying mechanisms, with multiple modes of action proposed. It also provides a glimpse of the reported therapeutic perspectives targeting capillary rarefaction. Further studies should address the reasons for such organ-specificity of capillary rarefaction, investigate strategies for its prevention and reversibility and examine potential signaling pathways that can be exploited to target it.

Association of serum growth differentiation factor-15 with eGFR and hemoglobin in healthy older females

Purpose

Anemia and sarcopenia associated with renal dysfunction caused by cytokine imbalance can contribute to decreased quality of life for older individuals. Growth differentiation factor-15 (GDF-15) is associated with renal dysfunction, although whether it is related to anemia or sarcopenia is unclear. In this study we examined the association of GDF-15 with renal function, hemoglobin and sarcopenia in healthy community-dwelling older females in Japan.

Methods

A total of 66 healthy older community-dwelling females (age: 75.8 ± 6.2 years) were enrolled for this study. Skeletal muscle mass index was determined by bioelectrical impedance analysis. Hand-grip strength and walking speed were also assessed. Serum GDF-15 concentration was determined by enzyme-linked immunosorbent assay and both hemoglobin (Hb) level and estimated glomerular filtration rate (eGFR) were measured.

Results

Serum GDF-15 levels positively correlated with age but negatively correlated with eGFR and walking speed. In multiple regression analysis, eGFR and hemoglobin (Hb) were independent variables to predict serum GDF-15 levels, even after adjusting for age and body mass index (eGFR: β = −0.423, p < 0.001; Hb: β = −0.363, p = 0.004). Serum GDF-15 level was an independent variable to predict eGFR and Hb.

Conclusions

Both Hb and eGFR are predictors for serum GDF-15 concentration in healthy older females. In these community-dwelling older females, renal dysfunction via GDF-15 may be accompanied by anemia, but not sarcopenia.

Nurse-led advance care planning with older people who have end-stage kidney disease: feasibility of a deferred entry randomised controlled trial incorporating an economic evaluation and mixed methods process evaluation (ACReDiT)

BACKGROUND

Advance Care Planning is recommended for people with end-stage kidney disease but evidence is limited. Robust clinical trials are needed to investigate the impact of advance care planning in this population. There is little available data on cost-effectiveness to guide decision makers in allocating resources for advance care planning. Therefore we sought to determine the feasibility of a randomised controlled trial and to test methods for assessing cost-effectiveness.

METHODS

A deferred entry, randomised controlled feasibility trial, incorporating economic and process evaluations, with people with end-stage kidney disease, aged 65 years or older, receiving haemodialysis, in two renal haemodialysis units in Northern Ireland, UK. A nurse facilitator helped the patient make an advance care plan identifying: a surrogate decision-maker; what the participant would like to happen in the future; any advance decision to refuse treatment; preferred place of care at end-of-life.

RESULTS

Recruitment lasted 189 days; intervention and data collection 443 days. Of the 67 patients invited to participate 30 (45%) declined and 36 were randomised to immediate or deferred advance care plan groups. Twenty-two (61%) made an advance care plan and completed data collection at 12 weeks; 17 (47.2%) were able to identify a surrogate willing to be named in the advance care plan document. The intervention was well-received and encouraged end-of-life conversations, but did not succeed in helping patients to fully clarify their values or consider specific treatment choices. There was no significant difference in health system costs between the immediate and deferred groups.

CONCLUSIONS

A trial of advance care planning with participants receiving haemodialysis is feasible and acceptable to patients, but challenging. A full trial would require a pool of potential participants five times larger than the number required to complete data collection at 3 months. Widening eligibility criteria to include younger (under 65 years of age) and less frail patients, together with special efforts to engage and retain surrogates may improve recruitment and retention. Traditional advance care planning outcomes may need to be supplemented with those that are defined by patients, helping them to participate with clinicians in making medical decisions.

TRIAL REGISTRATION

Registered December 16, 2015. ClinicalTrials.gov Identifier: NCT02631200 .

Resveratrol Pretreatment Ameliorates Concanavalin A-Induced Advanced Renal Glomerulosclerosis in Aged Mice through Upregulation of Sirtuin 1-Mediated Klotho Expression

Aging kidneys are characterized by an increased vulnerability to glomerulosclerosis and a measurable decline in renal function. Evidence suggests that renal and systemic klotho and sirtuin 1 (SIRT1) deficiencies worsen kidney damage induced by exogenous stresses. The aim of this study was to explore whether resveratrol would attenuate concanavalin A (Con A)-induced renal oxidative stress and advanced glomerulosclerosis in aged mice. Aged male C57BL/6 mice were treated orally with resveratrol (30 mg/kg) seven times (12 h intervals) prior to the administration of a single tail-vein injection of Con A (20 mg/kg). The plasma and urinary levels of kidney damage markers were evaluated. The kidney histopathology, renal parameters, and oxidative stress levels were measured. Furthermore, klotho was downregulated in mouse kidney mesangial cells that were pretreated with 25 µM resveratrol followed by 20 µg/mL Con A. The urinary albumin/creatinine ratio, blood urea nitrogen, kidney mesangial matrix expansion, tubulointerstitial fibrosis, and renal levels of α-smooth muscle actin, transforming growth factor beta, fibronectin, procollagen III propeptide, and collagen type I significantly increased in Con A-treated aged mice. Aged mice kidneys also showed markedly increased levels of 8-hydroxydeoxyguanosine (8-OH-dG) and reactive oxygen species (ROS), with reduced superoxide dismutase activity and levels of glutathione, klotho, and SIRT1 after Con A challenge. Furthermore, in kidney mesangial cells, klotho silencing abolished the effects of resveratrol on the Con A-mediated elevation of the indices of oxidative stress and the expression of glomerulosclerosis-related factors. These findings suggest that resveratrol protects against Con A-induced advanced glomerulosclerosis in aged mice, ameliorating renal oxidative stress via the SIRT1-mediated klotho expression.

Association of smoking with incident CKD risk in the general population: A community-based cohort study

BACKGROUND

Chronic kidney disease (CKD) is a public health problem, and an unfavorable lifestyle has been suggested as a modifiable risk factor for CKD. Cigarette smoking is closely associated with cardiovascular disease and cancers; however, there is a lack of evidence to prove that smoking is harmful for kidney health. Therefore, we aimed to determine the relationship between cigarette smoking and CKD among healthy middle-aged adults.

METHODS

Using the database from the Korean Genome and Epidemiology Study, we analyzed 8,661 participants after excluding those with baseline estimated glomerular filtration rate (eGFR)<60 ml/min/1.72 m2 or proteinuria. Exposure of interest was smoking status: never-, former-, and current-smokers. Primary outcome was incident CKD defined as eGFR <60 ml/min/1.73 m2 or newly developed proteinuria.

RESULTS

The mean age of the subjects was 52 years, and 47.6% of them were males. There were 551 (6.4%) and 1,255 (14.5%) subjects with diabetes and hypertension, respectively. The mean eGFR was 93.0 ml/min/1.73 m2. Among the participants, 5,140 (59.3%), 1,336 (15.4%), and 2,185 (25.2%) were never-smokers, former-smokers, and current-smokers, respectively. During a median follow-up of 11.6 years, incident CKD developed in 1,941 (22.4%) subjects with a crude incidence rate of 25.1 (24.0-26.2) per 1,000 person-years. The multivariable Cox regression analysis after adjustment of confounding factors showed hazard ratios (95% confidence interval) of 1.13 (0.95-1.35) and 1.26 (1.07-1.48) for CKD development in the former- and current-smokers, compared with never-smokers.

CONCLUSION

This study showed that smoking was associated with a higher risk of incident CKD among healthy middle-aged adults.

Health Care Costs by Type of Expenditure across eGFR Stages among Patients with and without Diabetes, Cardiovascular Disease, and Heart Failure

BACKGROUND

CKD is associated with higher health care costs that increase with disease progression. However, research is lacking on the type of health care costs associated with CKD across all stages in a general population with a substantial comorbidity burden.

METHODS

Using electronic medical records of an integrated delivery system, we evaluated health care costs by expenditure type in general and in patients with CKD by eGFR and presence of comorbidities. We categorized 146,132 patients with eGFR data in 2016 or 2017 and examined nonmutually exclusive groups according to presence of diabetes mellitus, cardiovascular disease, or heart failure. We used 1 year of follow-up data to calculate outpatient, inpatient, emergency, pharmaceutical, dialysis, and total health care costs by eGFR (Kidney Disease Improving Global Outcomes-defined eGFR categories), adjusted for age, sex, and nonwhite race.

RESULTS

Mean total health care costs among patients with CKD without comorbidities were 31% higher than among patients without CKD ($7374 versus $5631, respectively). Hospitalizations accounted for 35% of total costs among those with CKD and no comorbidities but up to 55% among patients with CKD and heart failure. The proportion of costs attributable to hospitalizations accelerated with declining kidney function, reaching as high as 66%.

CONCLUSIONS

Poorer kidney function and the presence of diabetes mellitus, cardiovascular disease, or heart failure drive substantial health care costs and increase the proportion of costs attributable to inpatient care. The large contribution of inpatient costs begins in earlier stages of CKD and escalates as kidney function declines. Additional therapies to reduce CKD incidence, slow CKD progression, and lower hospitalization risk are needed to benefit patients and reduce CKD's economic burden.

Effects of surrounding environment on incidence of end stage renal disease

The rising prevalence and incidence of end-stage renal disease (ESRD) have been noted around the world. However, no study has been conducted to examine the effect of surrounding environment on incidence of ESRD. This study assessed the associations of exposure to PM2.5 level and surrounding green spaces, separately, with incidence of ESRD in Taiwan. Demographic and clinical data used in this study was retrieved from the National Health Insurance Research Database from 2003 to 2012. PM2.5 data collected from the Environmental Protection Administration of Taiwan and a hybrid land-use regression model was used to approximate long-term exposure to PM2.5. Percentage of exposure to surrounding green spaces was used to determine individual exposure level. Cox proportional hazards models with a generalized estimating equation were applied to investigate the effect of surrounding environment on incidence of ESRD. The results showed significant positive association between exposure to PM2.5 level and incidence of ESRD; but inverse association between exposure to surrounding green spaces and incidence of ESRD (adjusted hazard ratio (AHR) = 1.08, 95% CI: 1.00-1.15 for exposure to PM2.5 level; AHR = 0.90, 95%CI: 0.84-0.98 for surrounding green spaces). Together, the findings from this study have added suggestive evidence on the adverse effect of exposure to PM2.5 level and the beneficial effect of exposure to surrounding green spaces on the incidence of ESRD in a general population in Taiwan.

Kidney disease progression and all-cause mortality across estimated glomerular filtration rate and albuminuria categories among patients with vs. without type 2 diabetes

BACKGROUND

Studies of progression of kidney dysfunction typically focus on renal replacement therapy or percentage decline in estimated glomerular filtration rate (eGFR) as outcomes. Our aim was to compare real-world patients with and without T2D to estimate progression from and to clinically defined categories of kidney disease and all-cause mortality.

METHODS

This was an observational cohort study of 31,931 patients with and 33,201 age/sex matched patients without type 2 diabetes (T2D) who had a serum creatinine and urine albumin-to-creatinine ratio (UACR) or dipstick proteinuria (DP) values. We used the first available serum creatinine value between 2006 and 2012 to calculate baseline eGFR and categorized them and the corresponding UACR/DP values using the Kidney Disease Improving Global Outcomes (KDIGO) categories. To assess our primary outcomes, we extracted probabilities of eGFR progression or mortality from life-table analyses and conducted multivariable Cox regression analyses of relative risk adjusted for age, sex, race/ethnicity, smoking, ischemic heart disease, heart failure, and use of renal-angiotensin-aldosterone system inhibitors.

RESULTS

Patterns of eGFR decline were comparable among patients with vs. without T2D with larger percentage declines at higher albuminuria levels across all eGFR categories. eGFR decline was generally larger among T2D patients, particularly in those with severely increased albuminuria. Across all CKD categories, risk of progression to the next higher category of eGFR was substantially increased with increasing albuminuria. For example, the risk was 23.5, 36.2, and 65.1% among T2D patients with eGFR 30-59 ml/min/1.73m2 and UACR < 30, 30-299, and > 300 mg/dL, respectively (p < 0.001). Other comparisons were similarly significant. Among patients with low eGFR and normal to mildly increased albuminuria, the relative risk was up to 8-fold greater for all-cause mortality compared with the non-CKD subgroup (eGFR> 60 ml/min/1.73m2 with normal to mildly increased albuminuria).

CONCLUSIONS

Presence of albuminuria was associated with accelerated eGFR decline independent of T2D. Risk for adverse outcomes was remarkably high among patients with CKD and normal to mildly increased albuminuria levels. Independent of T2D or albuminuria, a substantial risk for adverse outcomes exists for CKD patients in a routine care setting.

Aetiology of chronic kidney disease and risk factors for disease progression in Chinese subjects: A single-centre retrospective study in Beijing

Aim

To assess the aetiological factors of chronic kidney disease (CKD) and factors associated with disease progression.

Methods

Single‐centre retrospective study evaluating thorough electronic medical records of patients diagnosed with CKD at Peking University People's Hospital (April 2010‐April 2015). The objectives were to identify the aetiological factors of CKD in Chinese patients and risk factors associated with CKD progression.

Results

Of 15 425 CKD patients, 12 380 had aetiology recorded. The leading aetiologies associated with CKD were chronic glomerulonephritis (CGN; 36.8%), hypertensive nephropathy (HTN; 28.5%) and diabetic nephropathy (DN; 27.1%). CGN was most common in patients with early stage disease (stages 1‐2); DN and HTN were common in advanced‐stages (stages 3‐4). In a longitudinal subcohort of 2923 patients with ≥6‐month follow‐up, 19.6% experienced CKD progression. Patients with CKD progression were significantly older in age and had a greater number of comorbidities and laboratory anomalies, and were more likely to have DN (40.5%) and CGN (40.5%) than HTN (5.5%) at baseline than patients without progression. In a multivariate analysis, factors associated with disease progression included macro‐ and micro‐albuminuria, anaemia, hyperkalaemia, hyperphosphataemia, metabolic acidosis, CKD stage 4 and type 2 diabetes mellitus (T2DM).

Conclusion

This study identified CGN, DN and HTN as the leading aetiological factors for CKD in Chinese patients. DN was a strong predictor of faster disease progression, with albuminuria (a complication of T2DM) associated with highest risk for disease progression.

This study identified diabetic nephropathy was a strong predictor of faster disease progression, and confirmed albuminuria to be associated with highest risk for disease progression.

Investigating Possible Infectious Causes of Chronic Kidney Disease of Unknown Etiology in a Nicaraguan Mining Community

A chronic kidney disease of unknown etiology (CKDu) has been killing workers in Central America. Occupational heat stress is thought to play an important role. Leptospirosis and hantavirus have been suggested as additional possible risk factors. In a case–control study in a Nicaraguan mining community, a structured survey was administered to adults, and biological measurements and specimens were taken. Serum was analyzed for antibodies to Leptospira and hantavirus. Before statistical analysis, a board-certified nephrologist determined final case and control status based on serum creatinine and other laboratory values. Multivariable analysis was by logistic regression. In sensitivity analyses, cases were restricted to those diagnosed with CKDu in the previous 3 years. Of 320 eligible participants, 112 were classified as presumptive cases, 176 as controls and 32 as indeterminant. The risk of CKDu in those ever having worked in mining or construction was 4.4 times higher than in other participants (odds ratio = 4.44, 95% CI: 1.96–10.0, P = 0.0003). Eighty-three (26%) of the 320 participants were seropositive for at least one tested strain of Leptospira. No evidence of a causal link between leptospirosis or hantavirus and CKDu was found. The sensitivity analyses provide some evidence against the hypotheses that leptospirosis or hantavirus leads to CKDu within a few years. A major limitation was the impossibility of determining the absolute or relative timing of infection and CKDu onset. A prospective cohort design, with repeated collection of specimens over several years, could yield clearer answers about infections as potential etiologic agents in CKDu.

Is Health Literacy of Dialyzed Patients Related to Their Adherence to Dietary and Fluid Intake Recommendations?

Non-adherence to dietary and fluid intake recommendations (NADFIR) is an important factor for the effective treatment of dialyzed patients and may be hindered by low health literacy (HL). Therefore, we assessed whether low HL of dialyzed patients is associated with their NADFIR. We performed a multicentric cross-sectional study in 20 dialysis clinics in Slovakia (n = 452; response rate: 70.1%; mean age = 63.6 years; males: 60.7%). We assessed the association between nine domains of HL and non-adherence (high serum potassium, high serum phosphate, relative overhydration, and self-reported NADFIR) using general linear models adjusted for age and gender. Moreover, we assessed the moderation by socioeconomic status (SES). We found higher NADFIR among patients with less sufficient information for health management (high serum phosphate level; odds ratio (OR): 0.77; 95% confidence interval (CI): 0.63-0.94), with a lower ability to actively manage their health (self-reported diet non-adherence; OR: 0.74; 95% CI: 0.62-0.89), and those less able to actively engage with healthcare providers (overhydrated; OR: 0.78; 95% CI: 0.65-0.94). Moreover, SES modified this relation. Low HL affects the adherence of dialyzed patients. This shows a need to support patients with low HL and to train healthcare providers to work with these patients, taking into account their SES.

Chronic kidney disease in the pathogenesis of acute ischemic stroke

Chronic kidney disease has a graded and independent inverse impact on cerebrovascular health. Both thrombotic and hemorrhagic complications are highly prevalent in chronic kidney disease patients. Growing evidence suggests that in chronic kidney disease patients, ischemic strokes are more common than hemorrhagic strokes. Chronic kidney disease is asymptomatic until an advanced stage, but mild to moderate chronic kidney disease incites various pathogenic mechanisms such as inflammation, oxidative stress, neurohormonal imbalance, formation of uremic toxins and vascular calcification which damage the endothelium and blood vessels. Cognitive dysfunction, dementia, transient infarcts, and white matter lesions are widespread in mild to moderate chronic kidney disease patients. Uremic toxins produced after chronic kidney disease can pass through the blood-brain barrier and mediate cognitive dysfunction and neurodegeneration. Furthermore, chronic kidney disease precipitates vascular risk factors that can lead to atherosclerosis, hypertension, atrial fibrillation, and diabetes. Chronic kidney disease also exacerbates stroke pathogenesis, worsens recovery outcomes, and limits the eligibility of stroke patients to receive available stroke therapeutics. This review highlights the mechanisms involved in the advancement of chronic kidney disease and its possible association with stroke.

[Association of metabolic syndrome with chronic kidney disease in premenopausal and postmenopausal women]

OBJECTIVE

To explore the relationship between metabolic syndrome (MS) and the risk for chronic kidney disease (CKD) in premenopausal and postmenopausal women.

METHODS

We conducted a cross-sectional study among 1346 community-based women from June to October 2012 and collected the data of personal history, lifestyle, physical measures and laboratory indicators. The diagnosis of CKD was established for an eGFR of less than 60 mL/min per 1.73 m² or albuminuria. The diagnosis of metabolic syndrome was based on the International Diabetes Federation Guide. According to an epidemiological survey in Guangdong province, women older than 48.9 years were classified as having a postmenopausal status. The prevalence of MS and CKD was determined in both the premenopausal and postmenopausal women, and the association between MS and CKD was analyzed using logistic regression models.

RESULTS

MS was significantly correlated with CKD in premenopausal women in both unadjusted analyses (OR=3.10, 95% CI: 1.32-7.28, P=0.009) and in analysis after adjustment for potential confounders (OR=4.09, 95% CI: 1.63- 10.32, P=0.003). When adjusted for diabetes, hypertension, and hyperuricemia, no correlation was found between MS and CKD in premenopausal women (OR=1.56, 95% CI: 0.31-7.63, P= 0.592); in the unadjusted analyses, MS was significantly correlated with CKD in postmenopausal women (P &lt; 0.001). After further adjustment for age, education status, current smoking, physical inactivity, and current drinking, MS was still significantly correlated with CKD (OR=2.60, 95% CI: 1.69-3.99, P &lt; 0.001). When adjusted for diabetes, hypertension, and hyperuricemia, the correlation between MS and CKD was still significant (OR=1.61, 95% CI: 1.09-2.37, P=0.018). In the unadjusted model, a high blood pressure (OR=2.77, 95%CI: 1.57-4.89, P &lt; 0.001), an elevated serum triglyceride level (OR=1.84, 95%CI: 1.16-2.90, P=0.009) and a high fast glucose level (OR=2.07, 95%CI: 1.30-3.28, P=0.002) were all significantly correlated with CKD in postmenopausal women. After adjusting for age, current smoking, current alcohol use, education status and physical inactivity, a high blood pressure (OR=2.28, 95%CI: 1.22-4.26, P=0.01), a high serum triglyceride level (OR=1.71, 95%CI: 1.03-2.86, P=0.039) and a high fast glucose (OR=2.25, 95%CI: 1.36-3.73, P=0.002) were still significantly correlated with CKD in postmenopausal women. Blood pressure, serum triglyceride level, fast glucose, serum HDL cholesterol level and central obesity were not correlated with CKD in either the unadjusted model or adjusted model in premenopausal women (P &gt; 0.05).

CONCLUSIONS

MS is correlated with CKD in both premenopausal and postmenopausal women, and the association is dependent on diabetes, hypertension, and hyperuricemia in premenopausal women but not in postmenopausal women.

Uremic Pruritus: Prevalence and Impact on Quality of Life and Depressive Symptoms in Hemodialysis Patients

Background

End-stage renal disease (ESRD) is a major public health problem with many associated symptoms. Uremic pruritus (UP) develops in 40% of patients on hemodialysis and has major effects on the patient’s life. It is also an independent risk factor for increased mortality, and its psychiatric implications remain poorly characterized in our local setup, where it tends to be underdiagnosed and undertreated.

Objectives and rationale

The study aims to report the prevalence of uremic pruritus in our study population and associate it with various patient parameters, which may define a subset of patients at high risk for this pruritus. We also assess the effects of uremic pruritus on the patient’s quality of life (by using the Dermatology Life Quality Index; DLQI) and depressive symptoms (by using the Public Health Questionnaire; PHQ-9).

Materials and methods

It was a descriptive, cross-sectional study conducted in the nephrology unit of the multi-organ failure (MOF) center of the Holy Family Hospital (HFH), Rawalpindi, Pakistan, from February 2019 to June 2019, during which 173 male patients on hemodialysis were selected. Informed consent was taken from patients and other skin-related causes of pruritis were excluded. Uremic pruritus was defined as pruritis lasting for at least three months after the onset of ESRD. The 5-D, PHQ-9, and DLQI questionnaires were used to assess pruritis, depressive symptoms, and quality of life, respectively. Their Cronbach's Alpha values for 73 responses were 0.83, 0.81, and 0.71, respectively. The descriptive analysis was performed using SPSS v23.0 (IBM Corp, Armonk, NY, US). Spearman’s rank-order correlation, independent samples t-test, and one-way analysis of variance (ANOVA) were used to analyze study variables.

Results

The prevalence of uremic pruritus was 49.1%, with many patients having generalized itching. Unemployment and longer disease duration predisposed the patients towards uremic pruritus, as the mean 5-D score in this subset were greater (p<0.05 in the independent samples t-test). The results of one-way ANOVA were significant (p<0.05), indicating higher 5-D scores in worsening categories of depressive symptoms and quality of life. Spearman’s correlation matrix showed that 5-D, PHQ-9, and DLQI scores were strongly correlated with each other.

Conclusions

The prevalence of uremic pruritus among male hemodialysis patients is high, at 49.1%. It significantly contributes to depressive symptoms and a lower quality of life, which are associated with worse prognosis in hemodialysis patients. Thus, a clinician must keep in mind the psychiatric implications of uremic pruritus and treat it effectively to optimize the patient’s medical care.

Association between Plasma Levels of Growth Differentiation Factor-15 and Renal Function in the Elderly: Korean Frailty and Aging Cohort Study

BACKGROUND/AIMS

Growth differentiation factor-15 (GDF-15) expression has been reported to increase in response to tissue damage and has recently emerged as a useful biomarker for various diseases. Although emerging evidence supports the clinicopathological value of GDF-15 in renal impairment, few studies have analyzed it in the elderly. Thus, we conducted a cross-sectional study to investigate the association of plasma GDF-15 with renal function and the presence of chronic kidney disease (CKD) in community-dwelling elderly.

MATERIALS

The present study was based on the baseline data of the Korean Frailty and Aging Cohort Study (KFACS), a nationwide cohort study that began in 2016. Of the 1,559 participants assessed in the first year, 443 with available plasma GDF-15 data were enrolled in this study. We investigated the association of plasma GDF-15 levels with clinical and biochemical parameters. The study population was divided into two groups according to renal function (CKD and non-CKD groups) to investigate whether GDF-15 can determine the presence of renal dysfunction in the elderly. Plasma GDF-15 was measured by enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

In a simple regression analysis, the levels of plasma GDF-15 were negatively correlated with estimated glomerular filtration rate (eGFR; r = -0.383, p < 0.001). In multiple linear regression analysis, GDF-15 levels were still significantly correlated with eGFR, even after adjusting for other parameters (r = -0.259, p < 0.001). Plasma GDF-15 levels were significantly higher in the elderly with CKD than in those without CKD (2,364.025 ± 1,052.23 ng/L and 1,451.23 ± 835.79 ng/L, respectively; p < 0.001). The optimal cut-off value of plasma GDF-15 for detecting the presence of CKD was 1,699.4 ng/L (76.5% sensitivity and 76.0% specificity), as determined by the receiver operating characteristic curve. The area under the curve was 0.793 ± 0.033 (95% CI 0.729-0.857, p < 0.001).

CONCLUSION

Plasma GDF-15 levels were negatively associated with eGFR and were significantly increased in the elderly with CKD. Our results suggested that plasma GDF-15 might be a useful marker for discriminating renal impairment in the elderly. Further large and prospective outcome studies of extended duration are needed.

Incremental hemodialysis, a valuable option for the frail elderly patient

Management of older people on dialysis requires focus on the wider aspects of aging as well as dialysis. Recognition and assessment of frailty is vital in changing our approach in elderly patients. Current guidelines in dialysis have a limited evidence base across all age group, but particularly the elderly. We need to focus on new priorities of care when we design guidelines "for people not diseases". Patient-centered goal-directed therapy, arising from shared decision-making between physician and patient, should allow adaption of the dialysis regime. Hemodialysis (HD) in the older age group can be complicated by intradialytic hypotension, prolonged time to recovery, and access-related problems. There is increasing evidence relating to the harm associated with the delivery of standard thrice-weekly HD. Incremental HD has a lower burden of treatment. There appears to be no adverse clinical effects during the first years of dialysis in presence of a significant residual kidney function. The advantages of incremental HD might be particularly important for elderly patients with short life expectancy. There is a need for more research into specific topics such as the assessment of the course of frailty with progression of chronic kidney disease and after dialysis initiation, the choice of dialysis modality impacting on the trajectory of frailty, the timing of dialysis initiation impacting on frailty or on other outcomes. In conclusion, understanding each individual's goals of care in the context of his or her life experience is particularly important in the elderly, when overall life expectancy is relatively short, and life experience or quality of life may be the priority.

Serum Triglycerides Are Related to Chronic Kidney Disease (CKD) Stage 2 in Young and Middle-Aged Chinese Individuals During Routine Health Examination

BACKGROUND The aim of this study was to determine the risk factors for early chronic kidney disease (CKD) (GFR 60-89 ml/min/1.73 m²; CKD stage 2) in asymptomatic Chinese individuals undergoing routine health examination. MATERIAL AND METHODS This cross-sectional study enrolled 9100 individuals who received voluntary medical examinations between 10/01/2011 and 09/30/2017. Demographic data, clinical history, clinical examination, medication, smoking, alcohol, blood biochemistry, urinalysis, and carotid ultrasound were extracted from the medical records. All laboratory analyses were performed routinely. Multivariable logistic regression for factors predicting CKD stage 2 was performed. RESULTS A total of 9100 individuals were enrolled (age of 18-65 and 65.4% male). CKD stage 2 was found in 1989/9100 individuals (21.9%). Male gender (OR=6.711, 95%CI: 5.376-8.403, P<0.001), older age (OR=1.077, 95%CI: 1.068-1.086, P<0.001), hemoglobin levels (OR=1.051, 95%CI: 1.046-1.057, P<0.001), triglycerides levels (OR=1.174, 95%CI: 1.067-1.292, P=0.001), HDL-C (OR=0.539, 95%CI: 0.380-0.763, P<0.001), Lp(a) levels (OR=1.000, 95%CI: 1.000-1.001, P=0.03), and carotid atherosclerosis (OR=1.248, 95%CI: 1.005-1.550, P=0.045) were associated with CKD stage 2 among all subjects. Serum triglycerides levels were associated with CKD stage 2 in the 18-45 and 45-65 years of age subgroups. CONCLUSIONS Factors that are routinely assessed during routine health examinations (male gender, age, hemoglobin levels, triglycerides levels, HDL-C, Lp(a) levels, and carotid atherosclerosis) can help identify individuals at higher risk of having CKD stage 2. The Chinese dyslipidemia is characterized by high triglycerides and low HDL-C and occurs in young and middle-aged individuals. Those factors could help identify individuals at higher risk for CKD stage 2 and who could benefit from preventive treatments.

Predictores de progresión de enfermedad renal en el paciente anciano

El riñón del anciano experimenta cambios estructurales y funcionales, que lo convierte en más vulnerable para la enfermedad renal. La mayoría de ancianos con enfermedad renal crónica fallece antes de desarrollar progresión renal. Sin embargo, el principal grupo de pacientes incidentes de nefropatía terminal es el de personas mayores de 65 años, representando la diabetes mellitus y las causas vasculares sus principales etiologías. En esta revisión se analizan elementos renales (filtrado glomerular, proteinuria/albuminuria, potasio, fracaso renal agudo y diuréticos) y factores geriátricos (estado funcional, cognitivo y fragilidad) como predictores de progresión de enfermedad renal. La identificación de estos factores contribuirá a establecer estrategias de prevención renal y al pronóstico de la enfermedad en la toma decisiones.

Influence of age on the effect of reduced renal function on outcomes in patients with coronary artery disease

BACKGROUND

Ageing is a risk factor for both coronary artery disease (CAD) and reduced renal function (RRF), and it is also associated with poor prognosis in patients with CAD or RRF. However, little is known about whether the impact of RRF on clinical outcomes are different in CAD patients at different age groups. This study aimed to investigate whether ageing influences the effect of RRF on long-term risk of death in patients with CAD.

METHODS

A retrospective analysis was conducted using data from a single-center cohort study. Three thousand and two consecutive patients with CAD confirmed by coronary angiography were enrolled. RRF was defined as an estimated glomerular filtration rate (eGFR) of less than 60 ml/min. The primary endpoint in this study was all-cause mortality.

RESULTS

The mean follow-up time was 29.1 ± 12.5 months and death events occurred in 275 cases (all-cause mortality: 9.2%). The correlation analysis revealed a negative correlation between eGFR and age (r = - 0.386, P < 0.001). Comparing the younger group (age ≤ 59) with the elderly one (age ≥ 70), the prevalence of RRF increased from 5.9 to 27.5%. Multivariable Cox regression revealed that RRF was independently associated with all-cause mortality in all age groups, and the relative risks in older patients were lower than those in younger ones (age ≤ 59 vs. age 60-69 vs. age ≥ 70: hazard ratio [HR] 2.57, 95% confidence interval [CI] 1.04-6.37 vs. HR 2.00, 95% CI 1.17-3.42 vs. HR 1.46, 95% CI 1.06-2.02). There was a significant trend for HRs for all-cause mortality according to the interaction terms for RRF and age group (RRF*age [≤59] vs. RRF*age [60-69] vs. RRF*age [≥70]: HR 1.00[reference] vs. HR 0.60, 95% CI 0.23-1.54 vs. HR 0.32, 95% CI 0.14-0.75; P for trend = 0.010).

CONCLUSIONS

RRF may have different impacts on clinical outcomes in CAD patients at different age groups. The association of RRF with the risk of all-cause mortality was attenuated with ageing.

Effects of Probiotics on Inflammation and Uremic Toxins Among Patients on Dialysis: A Systematic Review and Meta-Analysis

BACKGROUND/OBJECTIVES

We performed this systematic review and meta-analysis to evaluate effects of probiotics on inflammation, uremic toxins, and gastrointestinal (GI) symptoms in end-stage renal disease (ESRD) patients.

METHODS

A literature search was conducted utilizing MEDLINE, EMBASE, and Cochrane Database from inception through October 2017. We included studies that assessed assessing effects of probiotics on inflammatory markers, protein-bound uremic toxins (PBUTs), and GI symptoms in ESRD patients on dialysis. Effect estimates from the individual study were extracted and combined utilizing random effect, generic inverse variance method of DerSimonian and Laird. The protocol for this meta-analysis is registered with PROSPERO; No. CRD42017082137.

RESULTS

Seven clinical trials with 178 ESRD patients were enrolled. There was a significant reduction in serum C-reactive protein (CRP) from baseline to post-probiotic course (≥ 2 months after treatment) with standardized mean difference (SMD) of - 0.42 (95% CI - 0.68 to - 0.16, p = 0.002). When compared to control, patients who received probiotics also had a significant higher degree of reduction in CRP level with SMDs of - 0.37 (95% CI - 0.72 to 0.03, p = 0.04). However, there were no significant changes in serum TNF-alpha or albumin with SMDs of - 0.32 (95% CI - 0.92 to 0.28, p = 0.29) and 0.16 (95% CI - 0.20 to 0.53, p = 0.39), respectively. After probiotic course, there were also significant decrease in PBUTs and improvement in overall GI symptoms (reduction in GI symptom scores) with SMDs of - 0.61 (95% CI - 1.16 to - 0.07, p = 0.03) and - 1.04 (95% CI - 1.70 to - 0.38, p = 0.002), respectively.

CONCLUSION

Our study demonstrates potential beneficial effects of probiotics on inflammation, uremic toxins, and GI Symptoms in ESRD patients. Future large-scale clinical studies are required to assess its benefits on other important clinical outcomes including patient mortality.

Prevalence and correlations of hepatorenal functions in diabetes and cardiovascular disease among stratified adults

Background: The vulnerability of older adults to diabetes and cardiovascular complications is a global concern. Hepatorenal pathophysiology is implicated in these complications, but has yet to be clearly established, especially from rural low-mid income countries. This study investigates differences in prevalence of diabetes in aging groups and correlations of age with hepatorenal variables. Methods: 203 participants of both sexes above the age of 18 years underwent anthropometric measurements at Catholic Hospital, Abbi, Nigeria. Questionnaires collected demographic information and medical history. Urinalysis as well as routine liver and renal function tests were performed. Data analysis included determination of levels of hepatorenal abnormalities and prevalence of diseases in age groups. Percentage of disease subpopulations made up by each age-group was also determined as well as Pearson’s correlation coefficient between age and hepatorenal variables, and comparison of average age and hepatorenal variables in disease subgroups. Results: Percentage hepatorenal abnormalities are not significantly different between age-groups. There is no significant difference in percentage level of disease between groups, but in age-groups constituting disease sub-populations (p<0.00001). The apparently healthy subpopulation comprises of younger adults compared to older adults constituting diabetes and hypertension (p < 0...). Age shows moderate correlation with renal function parameters, especially urea and chloride (r = 0.42), but relatively insignificant with liver function variables. Conclusion: This report affirms that diabetes cardiovascular co-morbidity comes with aging. It also indicates that renal pathophysiology may be more associated, than liver, functions in the vulnerability of adults. (www.actabiomedica.it)

A Systematic Review of Cognitive Impairments Associated With Kidney Failure in Adults Before Natural Age-Related Changes

OBJECTIVES

Recognition of cognitive impairment in chronic kidney disease (CKD) and its impact on functioning in adults is growing. The vast majority of studies to date have been conducted in older populations where CKD is more pronounced; however, the degree to which age-related cognitive changes could be influencing these findings remains unaddressed. This current study thus aimed to review cognitive impairment findings by stage in non-elderly CKD samples.

METHODS

PubMed and Medline via Scopus were searched for cross-sectional or cohort studies and randomized controlled trials that assessed cognitive function in individuals with CKD in any research setting. CKD studies including patients at any illness stage were included providing participants were below 65 years old, were not on peritoneal dialysis and had not undergone a kidney transplant.

RESULTS

Fifteen studies, with a total of 9304 participants, were included. Cognitive function broadly deteriorated from stage 1 to stage 5. Early stage CKD was associated with a drop in speed of processing, attention, response speed, and short-term memory abilities. Moderate stage CKD was associated with deficits in executive functioning, verbal fluency, logical memory, orientation and concentration. People with end stage kidney disease manifested significant deficits in all previous cognitive domains, along with cognitive control, delayed and immediate memory, visuospatial impairment, and overall cognitive impairment.

CONCLUSIONS

Cognitive impairment is evident across the stages of CKD, independent of age-related changes, for both lower-order and higher-order cognitive abilities. These impairments also increase between the stages, suggesting a cumulative effect. Future directions for research are discussed. (JINS, 2019, 25, 101-114).

Age Modifies the Association of Dietary Protein Intake with All-Cause Mortality in Patients with Chronic Kidney Disease

Whether the effect of a low-protein diet on progression to end-stage renal disease (ESRD) and mortality risk differs between young and elderly adults with chronic kidney disease (CKD) is unclear. We conducted a retrospective CKD cohort study to investigate the association between protein intake and mortality or renal outcomes and whether age affects this association. The cohort comprised 352 patients with stage G3-5 CKD who had been followed up for a median 4.2 years, had undergone educational hospitalization, and for whom baseline protein intake was estimated from 24-h urine samples. We classified the patients into a very low protein intake (VLPI) group (<0.6 g/kg ideal body weight/day), a low protein intake (LPI) group (0.6⁻0.8 g), and a moderate protein intake (MPI) group (>0.8 g). Compared with the LPI group, the MPI group had a significantly lower risk of all-cause mortality (hazard ratio: 0.29; 95% confidence interval: 0.07 to 0.94) but a similar risk of ESRD, although relatively high protein intake was related to a faster decline in the estimated glomerular filtration rate. When examined per age group, these results were observed only among the elderly patients, suggesting that the association between baseline dietary protein intake and all-cause mortality in patients with CKD is age-dependent.