US Renal Data System 2017 Annual Data Report: Epidemiology of Kidney Disease in the United States

Specific alterations in gut microbiota in patients with chronic kidney disease: an updated systematic review

BACKGROUND

Emerging evidence demonstrates that gut dysbiosis is implicated in the pathogenesis of chronic kidney disease (CKD) with underlying mechanisms involving mucosal and/or systematic immunity or metabolic disorders. However, the profile of gut microbiota in patients with CKD has not been completely explored.

METHODS

Databases from their date of inception to 31 March 2020 were systematically searched for case-control or cross-sectional studies comparing the gut microbial profiles in adult patients with CKD or end-stage renal disease (ESRD) with those in healthy controls. Quantitative analysis of alterations in gut microbial profiles was conducted.

RESULTS

Twenty-five studies with a total of 1436 CKD patients and 918 healthy controls were included. The present study supports the increased abundance of, phylum Proteobacteria and Fusobacteria, genus Escherichia_Shigella, Desulfovibrio, and Streptococcus, while lower abundance of genus Roseburia, Faecalibacterium, Pyramidobacter, Prevotellaceae_UCG-001, and Prevotella_9 in patients with CKD; and increased abundance of phylum Proteobacteria, and genus Streptococcus and Fusobacterium, while lower abundance of Prevotella, Coprococcus, Megamonas, and Faecalibacterium in patients with ESRD. Moreover, higher concentrations of trimethylamine-N-oxide and p-cresyl sulfate and lower concentrations of short-chain fatty acids were observed. Gut permeability in patients with CKD was not determined due to the heterogeneity of selected parameters.

CONCLUSIONS

Specific alterations of gut microbial parameters in patients with CKD were identified. However, a full picture of the gut microbiota could not be drawn from the data due to the differences in methodology, and qualitative and incomplete reporting of different studies.

Metabolic Health, Obesity, and Renal Function: 2013-2018 National Health and Nutrition Examination Surveys

Rising rates of metabolic syndrome, obesity, and mortality from chronic kidney disease (CKD) have prompted further investigation into the association between metabolic phenotypes and CKD. Purpose: To report the frequency of strictly defined metabolic phenotypes, renal function within each phenotype, and individual risk factors associated with reduced renal function. We utilized the 2013-2018 National Health and Nutrition Examination Surveys (NHANES) and complex survey sample weighting techniques to represent 220 million non-institutionalized U.S. civilians. Metabolic health was defined as having zero of the risk factors defined by the National Cholesterol Education Program with the exception of obesity, which was defined as BMI ≥ 30 kg/m2 in non-Asians and BMI ≥ 25 kg/m2 in Asians. The metabolically healthy normal (MUN) phenotype comprised the highest proportion of the population (38.40%), whereas the metabolically healthy obese (MHO) was the smallest (5.59%). Compared to the MHN reference group, renal function was lowest in the strictly defined MUN (B = -9.60, p < 0.001) and highest in the MHO (B = 2.50, p > 0.05), and this persisted when an increased number of risk factors were used to define metabolic syndrome. Systolic blood pressure had the strongest correlation with overall eGFR (r = -0.25, p < 0.001), and individuals with low HDL had higher renal function compared to the overall sample. The MUN phenotype had the greatest association with poor renal function. While the MHO had higher renal function, this may be due to a transient state caused by renal hyperfiltration. Further research should be done to investigate the association between dyslipidemia and CKD.

The Therapeutic Strategies for Uremic Toxins Control in Chronic Kidney Disease

Uremic toxins (UTs) are mainly produced by protein metabolized by the intestinal microbiota and converted in the liver or by mitochondria or other enzymes. The accumulation of UTs can damage the intestinal barrier integrity and cause vascular damage and progressive kidney damage. Together, these factors lead to metabolic imbalances, which in turn increase oxidative stress and inflammation and then produce uremia that affects many organs and causes diseases including renal fibrosis, vascular disease, and renal osteodystrophy. This article is based on the theory of the intestinal-renal axis, from bench to bedside, and it discusses nonextracorporeal therapies for UTs, which are classified into three categories: medication, diet and supplement therapy, and complementary and alternative medicine (CAM) and other therapies. The effects of medications such as AST-120 and meclofenamate are described. Diet and supplement therapies include plant-based diet, very low-protein diet, probiotics, prebiotics, synbiotics, and nutraceuticals. The research status of Chinese herbal medicine is discussed for CAM and other therapies. This review can provide some treatment recommendations for the reduction of UTs in patients with chronic kidney disease.

Multicentre Performance Evaluation of the Elecsys Anti-SARS-CoV-2 Immunoassay as an Aid in Determining Previous Exposure to SARS-CoV-2

Introduction

We performed a multicentre evaluation of the Elecsys^® Anti-SARS-CoV-2 immunoassay (Roche Diagnostics), an assay utilising a recombinant protein representing the nucleocapsid (N) antigen, for the in vitro qualitative detection of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods

Specificity was evaluated using serum/plasma samples from blood donors and routine diagnostic specimens collected before September 2019 (i.e., presumed negative for SARS-CoV-2-specific antibodies); sensitivity was evaluated using samples from patients with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection. Point estimates and 95% confidence intervals (CIs) were calculated. Method comparison was performed versus commercially available assays.

Results

Overall specificity for the Elecsys Anti-SARS-CoV-2 immunoassay (n = 9575) was 99.85% (95% CI 99.75–99.92): blood donors (n = 6714; 99.82%), routine diagnostic specimens (n = 2861; 99.93%), pregnant women (n = 2256; 99.91%), paediatric samples (n = 205; 100.00%). The Elecsys Anti-SARS-CoV-2 immunoassay demonstrated significantly higher specificity versus LIAISON SARS-CoV-2 S1/S2 IgG (99.71% vs. 98.48%), EUROIMMUN Anti-SARS-CoV-2 IgG (100.00% vs. 94.87%), ADVIA Centaur SARS-CoV-2 Total (100.00% vs. 87.32%) and iFlash SARS-CoV-2 IgM (100.00% vs. 99.58%) assays, and comparable specificity to ARCHITECT SARS-CoV-2 IgG (99.75% vs. 99.65%) and iFlash SARS-CoV-2 IgG (100.00% vs. 100.00%) assays. Overall sensitivity for Elecsys Anti-SARS-CoV-2 immunoassay samples drawn at least 14 days post-PCR confirmation (n = 219) was 93.61% (95% CI 89.51–96.46). No statistically significant differences in sensitivity were observed between the Elecsys Anti-SARS-CoV-2 immunoassay versus EUROIMMUN Anti-SARS-CoV-2 IgG (90.32% vs. 95.16%) and ARCHITECT SARS-CoV-2 IgG (84.81% vs. 87.34%) assays. The Elecsys Anti-SARS-CoV-2 immunoassay showed significantly lower sensitivity versus ADVIA Centaur SARS-CoV-2 Total (85.19% vs. 95.06%) and iFlash SARS-CoV-2 IgG (86.25% vs. 93.75%) assays, but significantly higher sensitivity versus the iFlash SARS-CoV-2 IgM assay (86.25% vs. 33.75%).

Conclusion

The Elecsys Anti-SARS-CoV-2 immunoassay demonstrated very high specificity and high sensitivity in samples collected at least 14 days post-PCR confirmation of SARS-CoV-2 infection, supporting its use to aid in determination of previous exposure to SARS-CoV-2.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00504-9.

Linagliptin in the Management of Type 2 Diabetes Mellitus After Kidney Transplant

BACKGROUND

The incidence and prevalence of end-stage renal disease (ESRD) is increasing. The most common cause of ESRD is diabetes mellitus (DM). Kidney transplantation offers better quality of life and survival for patients with ESRD. Because of the use of immunosuppressive therapy and steroids post-kidney transplantation, the patients are at an increased risk for the development of posttransplant DM (PTDM). Management of DM after transplantation (whether pre-existing or transplant related) remains a challenge. Multiple treatment options are currently available to manage PTDM. Those medications have good safety and efficacy record in the general population and in patients with mild degrees of kidney disease.

METHODS

We conducted a retrospective single center analysis of safety and efficacy of linagliptin post-kidney transplantation. The study was approved by the institutional review board. We collected data (demographics, laboratory tests, and any symptoms or hospitalizations) for 42 patients for a period of 12 months.

RESULTS

All 42 patients received linagliptin throughout the study period. Patients' average age was 62 years. Twenty-three were women and all were of Middle Eastern descent and had kidney transplants on average of 25 months when they were included in the study. Nineteen patients had DM before the transplant, and the rest had PTDM. Eighteen patients were on metformin and 15 were on insulin, whereas the rest were not on any other medications at the start of the study. Baseline average creatinine was 1.5 mg/dL (132.9 mmol/L) and glycated hemoglobin (HbA1c) was 8.2 g/dL at the start of the study, whereas creatinine was 1.6 mg/dL (138.5 mmol/L) and HbA1c was 7.4 g/dL at the end. HbA1c dropped 0.8 on average within 3 months of starting linagliptin and remained at the same level for the rest of the study. Urine protein did not change significantly throughout the study. Three patients developed acute myocardial infarction during the study, and a fourth one was hospitalized with an opportunistic infection. Two patients had urinary tract infections. Adverse effects were minimal. No allergic reactions, hypoglycemia, or acute pancreatitis episodes were reported. The average weight and body mass index did not change throughout the study. None of the patients stopped the medication.

CONCLUSIONS

In this retrospective analysis, linagliptin seems to be safe and efficacious after kidney transplantation. It can be considered as a treatment option to manage DM after transplantation.

Optimizing diabetes screening frequencies for at-risk groups

There is strong evidence that diabetes is underdiagnosed in the US: the Centers for Disease Control and Prevention (CDC) estimates that approximately 25% of diabetic patients are unaware of their condition. To encourage timely diagnosis of at-risk patients, we develop screening guidelines stratified by body mass index (BMI), age, and prior test history by using a Partially Observed Markov Decision Process (POMDP) framework to provide more personalized screening frequency recommendations. We identify structural results that prove the existence of threshold solutions in our problem and allow us to determine the relative timing and frequency of screening given different risk profiles. We then use nationally representative empirical data to identify a policy that provides the optimal action (screen or wait) every six months from age 45 to 90. We find that the current screening guidelines are suboptimal, and the recommended diabetes screening policy should be stratified by age and by finer BMI thresholds than in the status quo. We identify age ranges and BMI categories for which relatively less or more screening is needed compared to the existing guidelines to help physicians target patients most at risk. Compared to the status quo, we estimate that an optimal screening policy would generate higher net monetary benefits by $3,200-$3,570 and save $120-$1,290 in health expenditures per individual in the US above age 45.

Monitoring dialysis adequacy: history and current practice

Dialysis adequacy for pediatric patients has largely followed the trends in adult dialysis by judging the success or adequacy of peritoneal or hemodialysis with urea kinetic modeling. While this provides a starting point to establish a dose of dialysis, it is clear that urea is only part of the picture. Many clinical parameters and interventions now have been identified that are just as impactful on mortality and morbidly as urea clearance. As such, our concept of adequacy is evolving to include non-urea parameters and assessing the impact that following an "adequate therapy" has on patient lives. As we move to a new era, we consider the impact these therapies have on patients and how it affects the quality of their lives; we must take these factors into consideration to achieve a therapy that is not just adequate, but livable.

Kidney-Related Research in the United States: A Position Statement From the National Kidney Foundation and the American Society of Nephrology

Kidney disease is an important US public health problem because it affects over 37 million Americans, and Medicare expenditures for patients with chronic kidney disease now alone exceed $130 billion annually. Kidney disease is characterized by strong racial, ethnic, and socioeconomic disparities, and reducing kidney disease incidence will positively impact US health disparities. Due to the aging of the US population and an unabated obesity epidemic, the number of patients receiving treatment for kidney failure is anticipated to increase, which will escalate kidney disease health expenditures. The historical and current investment in kidney-related research via the National Institute of Diabetes and Digestive and Kidney Diseases has severely lagged behind ongoing expenditures for kidney disease care. Increasing research investment will identify, develop, and increase implementation of interventions to slow kidney disease progression, reduce incidence of kidney failure, enhance survival, and improve quality of life. This perspective states the urgent reasons why increasing investment in kidney-related research is important for US public health. The National Kidney Foundation and the American Society of Nephrology are working together to advocate for increased funding for the National Institute of Diabetes and Digestive and Kidney Diseases. The long-term goal is to reduce the burden of kidney disease in the US population and improve the quality of life of patients living with kidney disease.

L-ergothioneine and its combination with metformin attenuates renal dysfunction in type-2 diabetic rat model by activating Nrf2 antioxidant pathway

L-ergothioneine (L-egt) is a bioactive compound recently approved by the food and drug administration as a supplement. L-egt exerts potent cyto-protective, antioxidant and anti-inflammatory properties in tissues exposed to injury, while metformin is a first-line prescription in type-2 diabetes. Therefore, the present study investigated the protective effect of L-egt alone, or combined with metformin, on renal damage in a type-2 diabetic (T2D) rat model. T2D was induced in male Sprague-Dawley rats using the fructose-streptozotocin rat model. L-egt administration, alone or combined with metformin, began after confirming diabetes and was administered orally for seven weeks. After the experiment, all animals were euthanized by decapitation, blood samples were collected, and both kidneys were excised. Biochemical analysis, Enzyme-link Immunoassay (ELISA), Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR), western blotting, and histological analyses were done to evaluate various biomarkers and structural changes associated with renal damage. Untreated diabetic rats showed loss of kidney functions characterized by increased serum creatinine, blood urea nitrogen, proteinuria, triglycerides, lipid peroxidation, inflammation, and decreased antioxidant enzymes. Histological evaluation showed evidence of fibrosis, mesangial expansion, and damaged basement membrane in the nephrons. However, L-egt alleviates these functional and structural derangements in the kidney, while co-administration with metformin reduced hyperglycemia and improves therapeutic outcomes. Furthermore, L-egt treatment significantly increased the expression of major antioxidant transcription factors, cytoprotective genes and decreased the expression of inflammatory genes in the kidney. Thus, combining L-egt and metformin may improve therapeutic efficacy and be used as an adjuvant therapy to alleviate renal damage in type-2 diabetes.

Predictors of Aspiration Pneumonia and Mortality in Patients with Dysphagia

OBJECTIVES/HYPOTHESIS

To identify risk factors for pneumonia incidence in patients with dysphagia undergoing a videofluoroscopic swallow study (VFSS) in an outpatient tertiary-care center.

STUDY DESIGN

Historical cohort study.

METHODS

All individuals undergoing a VFSS between 10/02/13 and 07/30/15 were identified and followed historically for 2 years. Demographic information, medical history, and fluoroscopic data were collected. The 2-year incidence of pneumonia was obtained from the medical records and telephone interview. The incidence of pneumonia and death were calculated and risk factors for pneumonia and mortality were ascertained.

RESULTS

689 patients were followed for 2 years. The mean age (±standard deviation) of the cohort was 65 (±15.5) years. 49% (338/689) were female. The most common causes of dysphagia were cricopharyngeus muscle dysfunction (270/689), head and neck cancer (175/689), and neurodegenerative disease (56/689). The incidence of pneumonia was 22% (153/689). The incidence of death was 11%. Multivariable logistic regression revealed that chronic obstructive pulmonary disorder [COPD] (odds ratio [OR] = 2.36, 95% confidence interval [CI]: 1.33-4.19), hypertension (OR = 1.82, 95% CI: 1.23-2.73), tracheotomy status (OR = 2.96, 95% CI: 1.09-7.99), and vallecular residue (OR = 1.88, 95% CI: 1.24-2.85) were all significantly associated with an elevated risk of pneumonia. Kidney disease (OR = 1.27, 95% CI: 1.02-9.9), COPD (OR = 3.27, 95% CI: 1.65-6.49), vallecular residue (OR = 2.35, 95% CI: 1.35-4.1), male gender (OR = 2.21, 95% CI: 1.25-3.92), and low body mass index (OR: 1.12, 95% CI: 1.06-1.19) were independent adjusted risk factors for death.

CONCLUSIONS

The incidence of aspiration pneumonia (22%) and death (11%) within 2-years of a VFSS was high. The greatest adjusted risk factors for incident pneumonia were tracheotomy (OR = 3.0), COPD (OR = 2.4) and vallecular residue (OR = 1.9). The greatest adjusted risk factors for death were COPD (OR = 3.3), vallecular residue (OR = 2.3), and male gender (OR = 2.2).

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Apelin‑13 alleviates diabetic nephropathy by enhancing nitric oxide production and suppressing kidney tissue fibrosis

Diabetes is a serious metabolic disease, and the kidney damage induced by diabetes also seriously affects the survival of patients. Apelin is a molecule that plays a crucial role in lipid metabolism, and recent studies have revealed that apelin-13, a subtype of apelin, plays an important role in regulating blood glucose levels. However, the role of apelin-13 in diabetic nephropathy remains unclear. In the present study, a rat model of diabetic nephropathy was constructed by the injection of streptozocin (STZ). During this process, these rats were injected with apelin-13. The blood glucose, urine protein and insulin levels were determined weekly. Next, the expression of angiotensin domain type 1 receptor-associated protein (APJ), endothelial nitric oxide synthase (eNOS), E-cadherin and α-smooth muscle actin (α-SMA) in the kidney tissues was determined with western blotting. Then, the endothelial cells of glomerular vessels were cultured with high glucose medium. These cells were treated with apelin-13 for 24 h. Finally, cell viability of these cells and the expression of APJ, eNOS, E-cadherin and α-SMA in these cells were determined with western blotting. As a result, treatment of apelin-13 induced the lower levels of blood glucose and urine protein. In addition, application of apelin-13 promoted the production of insulin and alleviated the insulin resistance. Treatment with apelin-13 promoted the expression of APJ, eNOS and E-cadherin while it suppressed the expression of α-SMA in kidney tissues of rats and endothelial cells of glomerular vessels. Furthermore, application of apelin-13 also promoted the cell viability of these cells. In conclusion, apelin-13 relieved diabetic nephropathy by promoting the production of nitric oxide (NO) and alleviating the fibrosis of kidney tissues.

Cognitive mapping as an approach to facilitate organ donation among African Americans

Making up 13.4% of the United States population, African Americans (AAs) account for 28.7% of candidates who are currently waiting for an organ donation. AAs are disproportionately affected by end-organ disease, particularly kidney disease, therefore, the need for transplantation among this population is high, and the high need is also observed for other solid organ transplantation. To this end, we worked with the AA community to derive an empirical framework of organ donation strategies that may facilitate AA decision-making. We used a cognitive mapping approach involving two distinct phases of primary data collection and a sequence of data analytic procedures to elicit and systematically organize strategies for facilitating organ donation. AA adults (n = 89) sorted 27 strategies identified from nominal group technique meetings in phase 1 based on their perceived similarities. Sorting data were aggregated and analyzed using Multidimensional scaling and hierarchical cluster analyses. Among 89 AA participants, 68.2% were female, 65.5% obtained > high school education, 69.5% reported annual household income ≤ $50,000. The average age was 47.4 years (SD = 14.5). Derived empirical framework consisted of five distinct clusters: fundamental knowledge, psychosocial support, community awareness, community engagement, and system accountability; and two dimensions: Approach, Donor-related Information. The derived empirical framework reflects an organization scheme that may facilitate AA decision-making about organ donation and suggests that targeted dissemination of donor-related information at both the individual-donor and community levels may be critical for increasing donation rates among AAs.

Temporal evolution of C-reactive protein levels and its association with the incident hospitalization risk among individuals with stage 3-4 chronic kidney disease

BACKGROUND

Elevated C-reactive protein (CRP) levels as an inflammatory marker have been associated with poor outcomes in patients with chronic kidney disease (CKD). However, its single assessment may not reflect clinical significance before an adverse clinical endpoint. We studied the CRP level trajectories, which may be related with the intensity of the inflammatory process, and its association with time-to-first hospitalization in CKD.

METHODS

A cohort of 739 patients with stage 3-4 CKD were retrospectively observed for seven years. The time-to-event outcome was all-cause hospitalization. Clinical and laboratory features were measured at baseline. Longitudinal changes in naturally logged CRP levels were modeled using the Joint Longitudinal-Survival model adjusted with baseline covariates.

RESULTS

Logged CRP changes were evaluated with a median measurement (interquartile range) of 4 (2, 7), during a median (interquartile range) follow-up of 2.3 (1.2, 3.9) years. The estimated mean increase in logged CRP was 0.35 mg/L per year. 299 (40.5%) patients reached the endpoint, and increase in logged CRP with time was associated with increased risk of hospitalization (HR 1.96; 95% CI 1.05-3.66; p = 0.034), but baseline logged CRP did not have a significant effect on the time-to-first hospitalization (HR 0.98; 95% CI 0.85-1.13; p = 0.736).

CONCLUSION

All-cause hospitalization was associated significantly with CRP trajectories. Temporal evolutions of these repeatedly measured biomarkers might predict clinical outcomes in patients with CKD and may be useful for individual risk profiling. Furthermore, early management may provide an opportunity to better patient survival.

Artery to vein configuration of arteriovenous fistula improves hemodynamics to increase maturation and patency

Arteriovenous fistulae (AVF) are the preferred mode of hemodialysis access, but 60% of conventional [vein-to-artery (V-A)] AVF fail to mature, and only 50% remain patent at 1 year. We previously showed improved maturation and patency in a pilot study of the radial artery deviation and reimplantation (RADAR) technique that uses an artery-to-vein (A-V) configuration. Here, we show that RADAR exhibits higher rates of maturation, as well as increased primary and secondary long-term patencies. RADAR is also protective in female patients, where it is associated with decreased reintervention rates and improved secondary patency. RADAR and conventional geometries were compared further in a rat bilateral carotid artery-internal jugular vein fistula model. There was decreased cell proliferation and neointimal hyperplasia in the A-V configuration in male and female animals, but no difference in hypoxia between the A-V and V-A configurations. Similar trends were seen in uremic male rats. The A-V configuration also associated with increased peak systolic velocity and expression of Kruppel-like factor 2 and phosphorylated endothelial nitric oxide synthase, consistent with improved hemodynamics. Computed tomography and ultrasound-informed computational modeling showed different hemodynamics in the A-V and V-A configurations, and improving the hemodynamics in the V-A configuration was protective against neointimal hyperplasia. These findings collectively demonstrate that RADAR is a durable surgical option for patients requiring radial-cephalic AVF for hemodialysis access.

Increased risk of pulmonary and extrapulmonary tuberculosis infection in patients with polycystic kidney disease: a nationwide population-based study with propensity score-matching analysis

Background

Polycystic kidney disease (PKD) is a common renal disorder affecting approximately 1 in 1000 live births. Tuberculosis (TB) is an infectious disease worldwide. This study investigated the risk of TB infection in patients with PKD.

Methods

A nationwide population-based cohort study was performed using Taiwan’s National Health Insurance Research Database. We used patients’ hospitalization files for the entire analysis during 2000–2012. As per diagnosis, we divided patients into PKD and non-PKD cohorts and the major outcome was TB infection.

Results

A total of 13,540 participants with 6770 patients in each cohort were enrolled. The PKD cohort had a higher risk of TB infection than did the non-PKD cohort after adjusting for age, sex, and comorbidities (adjusted hazard ratio (aHR) = 1.91, 95% confidence interval [CI] = 1.51–2.43). When classifying by sites of pulmonary TB (PTB) and extrapulmonary TB (EPTB), the PKD cohort demonstrated a significantly higher risk of EPTB (aHR = 2.44, 95% CI = 1.46–4.08) as well as a risk of PTB (aHR = 1.69, 95% CI = 1.29–2.22). When stratified by the presence or absence of a comorbidity, high TB infection risk was noted in the PKD patients without any comorbidity (HR = 2.69, 95% CI = 1.69–4.30).

Conclusions

Taken together, our findings suggest that PKD is associated with a 1.91-fold increased risk of TB infection. Medical professionls should maintain a high index of suspicion in daily practice for patients with PKD, particularly those with EPTB infection.

Feasible kidney donation with living marginal donors, including diabetes mellitus

Objectives

To compare the donor outcomes of living donor kidney transplantation between standard donors (SDs) and marginal donors (MDs) including diabetic patients (MD + DM).

Methods

MDs were defined according to Japanese guideline criteria: (a) age >70‐years, (b) blood pressure ≤130/80 mmHg on hypertension medicine, (c) body mass index >25 to ≤32 kg/m², (d) 24‐h creatinine clearance ≥70 to <80 ml/min/1.73 m², and (e) hemoglobin A1c > 6.2 or ≤6.5 with oral diabetic medicine. Fifty‐three of 114 donors were MDs. We compared donor kidney functions until 60 months postoperatively.

Results

No kidney function parameters were different between SDs and MDs. When comparing SD and MD + DM, MD + DM had a lower postoperative eGFR (48 vs. 41 (1 (month), p = .02), 49 vs. 40 (12, p < .01), 48 vs. 42 (24, p = .04), 47 vs. 38 (36, p = .01)) and the percentage of residual eGFR (SD vs. MD + DM: 63 vs. 57 (1 (month), p < .01), 63 vs. 57 (2, p < .01), 64 vs. 56 (12, p < .01), 63 vs. 57 (24, p < .01), 63 vs. 52 (36, p = .02)). However, when MD with a single risk factor of DM was compared to SD, the difference disappeared. Nine out of 12 (75%) MD + DM had ≥2 risk factors.

Conclusions

Although long‐term observation of donor kidney function is necessary, careful MD + DM selection had the potential to expand the donor pool.

A systematic review and meta-analysis of cell-based interventions in experimental diabetic kidney disease

Regenerative, cell‐based therapy is a promising treatment option for diabetic kidney disease (DKD), which has no cure. To prepare for clinical translation, this systematic review and meta‐analysis summarized the effect of cell‐based interventions in DKD animal models and treatment‐related factors modifying outcomes. Electronic databases were searched for original investigations applying cell‐based therapy in diabetic animals with kidney endpoints (January 1998‐May 2019). Weighted or standardized mean differences were estimated for kidney outcomes and pooled using random‐effects models. Subgroup analyses tested treatment‐related factor effects for outcomes (creatinine, urea, urine protein, fibrosis, and inflammation). In 40 studies (992 diabetic rodents), therapy included mesenchymal stem/stromal cells (MSC; 61%), umbilical cord/amniotic fluid cells (UC/AF; 15%), non‐MSC (15%), and cell‐derived products (13%). Tissue sources included bone marrow (BM; 65%), UC/AF (15%), adipose (9%), and others (11%). Cell‐based therapy significantly improved kidney function while reducing injury markers (proteinuria, histology, fibrosis, inflammation, apoptosis, epithelial‐mesenchymal‐transition, oxidative stress). Preconditioning, xenotransplantation, and disease‐source approaches were effective. MSC and UC/AF cells had greater effect on kidney function while cell products improved fibrosis. BM and UC/AF tissue sources more effectively improved kidney function and proteinuria vs adipose or other tissues. Cell dose, frequency, and administration route also imparted different benefits. In conclusion, cell‐based interventions in diabetic animals improved kidney function and reduced injury with treatment‐related factors modifying these effects. These findings may aid in development of optimal repair strategies through selective use of cells/products, tissue sources, and dose administrations to allow for successful adaptation of this novel therapeutic in human DKD.

CKD Prevalence in the Military Health System: Coded Versus Uncoded CKD

Rationale & Objective

Chronic kidney disease (CKD) is common but often goes unrecorded.

Study Design

Cross-sectional.

Setting & Participants

Military Health System (MHS) beneficiaries aged 18 to 64 years who received care during fiscal years 2016 to 2018.

Predictors

Age, sex, active duty status, race, diabetes, hypertension, and numbers of kidney test results.

Outcomes

We defined CKD by International Classification of Diseases, Tenth Revision (ICD-10) code and/or a positive result on a validated electronic phenotype that uses estimated glomerular filtration rate and measures of proteinuria with evidence of chronicity. We defined coded CKD by the presence of an ICD-10 code. We defined uncoded CKD by a positive e-phenotype result without an ICD-10 code.

Analytical Approach

We compared coded and uncoded populations using 2-tailed t tests (continuous variables) and Pearson χ² test for independence (categorical variables).

Results

The MHS population included 3,330,893 beneficiaries. Prevalence of CKD was 3.2%, based on ICD code and/or positive e-phenotype result. Of those identified with CKD, 63% were uncoded. Compared with beneficiaries with coded CKD, those with uncoded CKD were younger (aged 45 ± 13 vs 52 ± 11 years), more often women (54.4% vs 37.6%) and active duty (20.2% vs 12.5%), and less often of Black race (18.5% vs 31.5%) or with diabetes (23.5% vs 43.5%) or hypertension (46.6% vs 77.1%; P < 0.001). Beneficiaries with coded (vs uncoded) CKD had greater numbers of kidney test results (P < 0.001).

Limitations

Use of cross-sectional administrative data prevents inferences about causality. The CKD e-phenotype may fail to capture CKD in individuals without laboratory data and may underestimate CKD.

Conclusions

The prevalence of CKD in the MHS is ~3.2%. Beneficiaries with well-known CKD risk factors, such as older age, male sex, Black race, diabetes, and hypertension, were more likely to be coded, suggesting that clinicians may be missing CKD in groups traditionally considered lower risk, potentially resulting in suboptimal care.

Intradialytic exercise in end-stage renal disease: An umbrella review of systematic reviews and/or meta-analytical studies

OBJECTIVES

This umbrella review aimed to understand the clinical benefits and adverse events associated with different modalities of intradialytic exercise in patients with end-stage renal disease undergoing hemodialysis.

DATA SOURCES

The search was performed until September 10th, 2020 on Scopus, Web of Science, the Cochrane Database, CINAHL, and PubMed.

METHODS

This umbrella review was conducted following the PRISMA guideline statement. The methodological quality of the reviews was assessed with the AMSTAR-2. Standardized mean differences with 95% confidence intervals were estimated. The I-squared statistic was used to assess heterogeneity and the Eggers' test was performed to test asymmetry/small-study effects.

RESULTS

Eleven reviews were included and 48 unique meta-analyses were examined. Nine were supported by suggestive evidence (P < 0.05, small heterogeneity, absence of small-study effects, and excess significance bias). Clinical benefits were found for functional capacity associated with aerobic exercise (d = 0.81; k = 6), resistance training (d = 0.58; k = 6), neuromuscular electrical stimulation (d = 0.70; k = 5), and inspiratory muscle training (d = 1.13; k = 2), measured by the distance covered in the 6-minutes walking test. This outcome was also associated with aerobic exercise (d = 0.28; k = 7) and combined exercise, measured by VO2peak (d = 1.01; k = 5) and by the duration of the cardiopulmonary test (d = 1.07; k = 4). Isometric quadriceps muscle strength improved with neuromuscular electrical stimulation (d = 1.19; k = 7) while patients' perception of vitality improved with combined exercise (d = 0.60; k = 3).

CONCLUSIONS

Suggestive evidence was found for the associations between various modalities of intradialytic exercise and functional capacity. Combined exercise was associated with improvements in physical and psychosocial variables. Few or no adverse events were reported.

Chronic kidney disease progression among patients with type 2 diabetes identified in US administrative claims: a population cohort study

BACKGROUND

Chronic kidney disease (CKD), one of the most common complications of type 2 diabetes (T2D), is associated with poor health outcomes and high healthcare expenditures. As the CKD population increases, a better understanding of the prevalence and progression of CKD is critical. However, few contemporary studies have explored the progression of CKD relative to its onset in T2D patients using established markers derived from real-world care settings.

METHODS

This retrospective, population-based cohort study assessed CKD progression among adults with T2D and with newly recognized CKD identified from US administrative claims data between 1 January 2008 and 30 September 2018. Included were patients with T2D and laboratory evidence of CKD as indicated by the established estimated glomerular filtration rate (eGFR) and urine albumin:creatinine ratio (UACR) criteria. Disease progression was described as transitions across the eGFR- and UACR-based stages.

RESULTS

A total of 65 731 and 23 035 patients with T2D contributed to the analysis of eGFR- and UACR-based CKD stage progression, respectively. CKD worsening was observed in approximately 10-17% of patients over a median follow-up of 2 years. Approximately one-third of patients experienced an increase in eGFR values or a decrease in UACR values during follow-up.

CONCLUSIONS

A relatively high proportion of patients were observed with disease progression over a short period of time, highlighting the need for better identification of patients at risk of rapidly progressive CKD. Future studies are needed to determine the clinical characteristics of these patients to inform earlier diagnostic and therapeutic interventions aimed at slowing disease progression.

Low Health Literacy is Associated with the Onset of CKD during the Life Course

BACKGROUND

Health literacy, the ability to deal with information related to one's health, is a predictor of health outcomes in CKD. However, research has not explored whether low health literacy predicts the onset of CKD.

METHODS

We used data from participants of Lifelines, a prospective population-based cohort study of individuals living in The Netherlands, to assess the share of individuals with low health literacy by eGFR category, whether low health literacy is associated with CKD onset in the general population and in the subgroup of older adults, and whether established CKD risk factors mediate this association.

RESULTS

In the total sample of 93,885 adults (mean follow-up 3.9 years), low health literacy was more likely among individuals in worse eGFR categories, increasing from 26.4% in eGFR category 1 to 50.0% in category 5 (P=0.02). Low health literacy, compared with adequate health literacy, was associated with the onset of CKD in the total sample (3.0% versus 2.1%) and in the subgroup of older adults (13.4% versus 11.3%), with odds ratios (ORs) of 1.44 (95% confidence interval (95% CI), 1.31 to 1.59) and 1.21 (95% CI, 1.04 to 1.41), respectively. After adjustment for sex, age, education, and income, health literacy was associated with CKD onset only in older adults (OR, 1.25; 95% CI, 1.04 to 1.50). This association was mediated by hypertension and high body mass index (BMI) in the crude model, but only by BMI after adjustment (with BMI explaining 18.8% of the association).

CONCLUSIONS

Low health literacy is a risk factor for CKD onset among older adults, which suggests that CKD prevention might benefit from strategies to address low health literacy.

Ginsenoside Rh1 Improves Type 2 Diabetic Nephropathy through AMPK/PI3K/Akt-Mediated Inflammation and Apoptosis Signaling Pathway

Although ginseng (Panax ginseng C.A. Meyer) has received extensive attention in the treatment and prevention of type 2 diabetes mellitus (T2DM) in the past few decades, there are few studies on the complications of T2DM. At present, obesity-linked diabetic nephropathy (DN) has become the most prevailing element of the end-stage renal failure in the world. The aim of this work is to evaluate the ameliorative effects of ginsenoside Rh1 (G-Rh1) on DN induced by high fat diet plus streptozotocin (HFD/STZ) through some potential and combined mechanisms of action. The results showed that G-Rh1 treatment at 5 and 10 mg/kg for 8 weeks exerted excellent effects in controlling fasting blood glucose (FBG), improving glucose tolerance, and increasing insulin level. In addition, G-Rh1 effectively prevents the excessive production of advanced glycation end products (AGEs), a diabetic nephropathy marker, in HFD/STZ induced DN mice. Meanwhile, oxidation indicators including SOD, GSH, and MDA were improved by G-Rh1 treatment to varying degrees. It is worth noting that G-Rh1 not only inhibits the secretion of Nox1 and Nox4 in kidney tissues, but also has an inhibitory effect on inflammatory factors and NF-[Formula: see text]B signaling pathway. Importantly, further in-depth research on molecular mechanisms provides vital evidence that the ameliorative effect of G-Rh1 on DN is related to the inhibition of apoptosis and the AMPK/PI3K/Akt signaling pathway. In summary, G-Rh1 may be of great value in improving the treatment of DN although more experimental data is needed.

Mortality, hospitalization and transfer to haemodialysis and hybrid therapy, in Japanese peritoneal dialysis patients

BACKGROUND AND OBJECTIVES

Survival of peritoneal dialysis (PD) patients in Japan is high, but few reports exist on cause-specific mortality, transfer to haemodialysis (HD) or hybrid dialysis and hospitalisation risks. We aimed to identify reasons for transfer to HD, hybrid dialysis and hospitalisation in the Japan Peritoneal Dialysis and Outcomes Practice Patterns Study.

METHODS

This observational study included 808 adult PD patients across 31 facilities in Japan in 2014-2017. Information on all-cause and cause-specific mortality and hospitalisation and permanent transfer to HD and PD/HD hybrid therapy were prospectively collected and rates calculated.

RESULTS

Median follow-up time was 1.66 years where 162 patients transferred to HD, 79 transferred to hybrid dialysis and 74 patients died. All-cause and cardiovascular disease (CVD)-related mortality rates were 5.1 and 1.7 deaths/100 patient-years, respectively. Rates of transfer to HD and hybrid therapy were 11.2 and 5.5 transfers/100 patient-years, respectively. Among HD transfers, 40% were due to infection (including peritonitis), while 20% were due to inadequate solute/water clearance. Eighty-one percent of hybrid dialysis transfers were due to inadequate solute/water clearance. All--cause, peritonitis-related and CVD-related hospitalisation rates were 120.4, 21.1 and 15.6/100 patient-years, respectively. Median hospital length of stay was 19 days.

CONCLUSIONS

Mortality, hospitalisation and transfer to HD/hybrid dialysis rates are relatively low in Japan compared to many other countries with hybrid transfers, accounting for one-third of dialysis transfers from PD. Further study is needed to explain the high inter-facility variation in hospitalisation rates and how to further reduce hospitalisation rates for Japanese PD patients.

The Immunomodulatory Effect of the Gut Microbiota in Kidney Disease

The human gut microbiota is a complex cluster composed of 100 trillion microorganisms, which holds a symbiotic relationship with the host under normal circumstances. Intestinal flora can facilitate the treatment of human metabolic dysfunctions and interact with the intestinal tract, which could influence intestinal tolerance, immunity, and sensitivity to inflammation. In recent years, significant interests have evolved on the association of intestinal microbiota and kidney diseases within the academic circle. Abnormal changes in intestinal microbiota, known as dysbiosis, can affect the integrity of the intestinal barrier, resulting in the bacterial translocation, production, and accumulation of dysbiotic gut-derived metabolites, such as urea, indoxyl sulfate (IS), and p-cresyl sulfate (PCS). These processes lead to the abnormal activation of immune cells; overproduction of antibodies, immune complexes, and inflammatory factors; and inflammatory cell infiltration that can directly or indirectly cause damage to the renal parenchyma. The aim of this review is to summarize the role of intestinal flora in the development and progression of several renal diseases, such as lupus nephritis, chronic kidney disease, diabetic nephropathy, and renal ischemia-reperfusion injury. Further research on these mechanisms should provide insights into the therapeutic potential of regulating intestinal flora and intervening related molecular targets for the abovementioned nephropathy.

Nomenclature for kidney function and disease-executive summary and glossary from a Kidney Disease: Improving Global Outcomes (KDIGO) consensus conference

The worldwide burden of kidney disease is rising, but public awareness remains limited, underscoring the need for more effective communication by stakeholders in the kidney health community. Despite this need for clarity, the nomenclature for describing kidney function and disease lacks uniformity. In June 2019, Kidney Disease: Improving Global Outcomes (KDIGO) convened a consensus conference with the goal of standardizing and refining the nomenclature used in the English language to describe kidney function and disease, and of developing a glossary that could be used by journals in scientific publications. Guiding principles of the conference were that the revised nomenclature should be patient-centred, precise, and consistent with nomenclature used in the KDIGO guidelines. Conference attendees reached general consensus on the following recommendations: (i) to use 'kidney' rather than 'renal' or 'nephro' when referring to kidney disease and kidney function; (ii) to use 'kidney failure' with appropriate descriptions of the presence or absence of symptoms, signs, and treatment rather than 'end-stage' kidney disease; (iii) to use the KDIGO definition and classification of acute kidney diseases and disorders (AKD) and acute kidney injury (AKI) rather than alternative descriptions to define and classify the severity of AKD and AKI; (iv) to use the KDIGO definition and classification of chronic kidney disease (CKD) rather than alternative descriptions to define and classify the severity of CKD; and (v) to use specific kidney measures, such as albuminuria or decreased glomerular filtration rate, rather than 'abnormal or reduced kidney function' to describe alterations in kidney structure and function. A proposed five-part glossary contains specific items for which there was general agreement. Conference attendees acknowledged limitations of the recommendations and glossary but considered that standardizing scientific nomenclature is essential for improving communication.

[Calpain activation promotes dialysis-associated peritoneal fibrosis in rats]

OBJECTIVE

To explore the role of calpain activation in the progression of peritoneal fibrosis.

OBJECTIVE

Twenty-four male Sprague-Dawley rats were randomized equally into control group, MDL28170 (a calpain inhibitor)+normal saline group, peritoneal dialysis (PD) model group and PD + MDL28170 group. In the latter two groups, the rats received daily intraperitoneal injections of 100 mL/kg of 4.25% glucose PD solution, and those in PD+MDL28170 group and MDL28170 saline group received daily infusion of 4 mg/kg MDL28170 every other day. Eight weeks later, the rats were euthanized for pathological examination of the parietal peritoneum, and the visceral peritoneum was used for examining the activation status of calpain and the expressions of fibronectin (FN) and collagen I (COL-I). Calpain activation and expressions of FN, COL-I and α-SMA were also examined using Western blotting and immunofluorescence assay in primary cultures of rat peritoneal mesothelial cells treated with MDL28170, transforming growth factor-β (TGF-β), or both.

OBJECTIVE

Compared with the control rats, the rats in PD model group showed significantly increased peritoneal peritoneum thickness, calpain activation in the peritoneal tissue, and expressions of FN and COL-I (P < 0.05). Treatment with MDL28170 significantly alleviated associated peritoneal fibrosis, decreased the thickness of the peritoneum (P < 0.05), and reduced the expressions of FN and COL-I in the rats with daily PD (P < 0.05). In the in vitro experiment, the expressions of FN and COL-I were also significantly lower in rat peritoneal mesothelial cells treated with both MDL28170 and TGF-β than in the cells treated with TGF-β alone (P < 0.05).

OBJECTIVE

Peritoneal calpain activity and expressions FN and COL-I all increase significantly in rat models of PD-associated peritoneal fibrosis. Calpain activation can promote peritoneal fibrosis, and inhibition of calpain can alleviate peritoneal fibrosis.

Estimated left ventricular pressure-myocardial strain loop as an index of cardiac work predicts all-cause mortality in patients receiving regular hemodialysis

BACKGROUND

A non-invasive method for left ventricular pressure-strain analysis has recently been introduced to provide information on cardiac work and detect subtler changes in cardiac function. This study aims to verify and construct a novel index that could accurately and independently predict the prognosis of patients with end-stage kidney disease (ESRD) receiving regular hemodialysis.

METHODS

Patients with end-stage kidney disease (ESRD) receiving maintenance hemodialysis (4-h sessions, 3 times weekly for 3 months or more) and who underwent echocardiography between 2009 and 2014 in China Medical University Hospital, Taichung, Taiwan, were enrolled. Conventional (left ventricular ejection fraction, LVEF) and strain echocardiography parameters (global longitudinal strain, GLS; cardiac work index, CWI) in 102 eligible patients were analyzed and compared. CWI was calculated from estimated LV pressure-myocardial strain loop area.

RESULTS

Results show that, while no significant differences were found between LVEF (0.57 ± 0.12 vs. 0.59 ± 0.09, P = 0.27) and GLS (-16.12 ± 6.57% vs. -18.44 ± 5.54%, P = 0.07), deceased patients had significantly lower CWI (1339 ± 683.05 mmHg% vs. 1883.38 ± 640.99 mmHg%, P = 0.0002) than surviving patients. The predictive values defined by area under the curve (AUC) of LVEF, GLS and CWI were 0.499, 0.619 and 0.724, respectively.

CONCLUSION

In conclusion, CWI is an accurately independent predictor of all-cause mortality in ESRD patients receiving regular hemodialysis and may superior to the current predictors such as LVEF and GLS.

Epigenome-wide association study of kidney function identifies trans-ethnic and ethnic-specific loci

BACKGROUND

DNA methylation (DNAm) is associated with gene regulation and estimated glomerular filtration rate (eGFR), a measure of kidney function. Decreased eGFR is more common among US Hispanics and African Americans. The causes for this are poorly understood. We aimed to identify trans-ethnic and ethnic-specific differentially methylated positions (DMPs) associated with eGFR using an agnostic, genome-wide approach.

METHODS

The study included up to 5428 participants from multi-ethnic studies for discovery and 8109 participants for replication. We tested the associations between whole blood DNAm and eGFR using beta values from Illumina 450K or EPIC arrays. Ethnicity-stratified analyses were performed using linear mixed models adjusting for age, sex, smoking, and study-specific and technical variables. Summary results were meta-analyzed within and across ethnicities. Findings were assessed using integrative epigenomics methods and pathway analyses.

RESULTS

We identified 93 DMPs associated with eGFR at an FDR of 0.05 and replicated 13 and 1 DMPs across independent samples in trans-ethnic and African American meta-analyses, respectively. The study also validated 6 previously published DMPs. Identified DMPs showed significant overlap enrichment with DNase I hypersensitive sites in kidney tissue, sites associated with the expression of proximal genes, and transcription factor motifs and pathways associated with kidney tissue and kidney development.

CONCLUSIONS

We uncovered trans-ethnic and ethnic-specific DMPs associated with eGFR, including DMPs enriched in regulatory elements in kidney tissue and pathways related to kidney development. These findings shed light on epigenetic mechanisms associated with kidney function, bridging the gap between population-specific eGFR-associated DNAm and tissue-specific regulatory context.

MRC2 Promotes Proliferation and Inhibits Apoptosis of Diabetic Nephropathy

Diabetic nephropathy (DN) is an important microvascular complication of diabetes and is the main cause of end-stage renal disease. Type 2 mannose receptor C (MRC2) is a member of the mannose receptor protein family, which has been confirmed to have the ability to promote the cell migration signaling pathway and invasion. By complementary DNA chip screening and analysis, we found that the expression of MRC2 was upregulated in the kidneys of mice with diabetic nephropathy. However, the role of MRC2 in diabetic nephropathy is still unclear. This work studied the effect of MRC2 on diabetic nephropathy. After verifying the results of the chip by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting, we used small interfering RNAs (siRNAs) to knock down the expression of MRC2 in mouse mesangial cells (MMCs) and analyzed the level of cell proliferation and apoptosis using western blotting, Cell Counting Kit-8, and flow cytometry. The results showed that the MRC2 knockdown inhibited MMC proliferation and induced cell apoptosis. These results suggest that MRC2 may be a molecular marker and a therapeutic target for diabetic nephropathy.

Stratified Cox models with time-varying effects for national kidney transplant patients: A new blockwise steepest ascent method

Analyzing the national transplant database, which contains about 300,000 kidney transplant patients treated in over 290 transplant centers, may guide the disease management and inform the policy of kidney transplantation. Cox models stratified by centers provide a convenient means to account for the clustered data structure, while studying more than 160 predictors with effects that may vary over time. As fitting a time-varying effect model with such a large sample size may defy any existing software, we propose a blockwise steepest ascent procedure by leveraging the block structure of parameters inherent from the basis expansions for each coefficient function. The algorithm iteratively updates the optimal blockwise search direction, along which the increment of the partial likelihood is maximized. The proposed method can be interpreted from the perspective of the minorization-maximization algorithm and increases the partial likelihood until convergence. We further propose a Wald statistic to test whether the effects are indeed time varying. We evaluate the utility of the proposed method via simulations. Finally, we apply the method to analyze the national kidney transplant data and detect the time-varying nature of the effects of various risk factors.

Greater variability in lipid measurements associated with kidney diseases in patients with type 2 diabetes mellitus in a 10-year diabetes cohort study

This study aimed to evaluate the associations between variability of lipid parameters and the risk of kidney disease in patients with type 2 diabetes mellitus. Low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were specifically addressed in this study. This retrospective cohort study included 105,552 patients aged 45-84 with type 2 diabetes mellitus and normal kidney function who were managed under Hong Kong public primary care clinics during 2008-2012. Those with kidney disease (estimated glomerular filtration rate < 60 mL/min/1.73 m2 or urine albumin to creatinine ratio ≥ 3 mg/mmol) were excluded. Variabilities of low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were determined using the standard deviation of the respective parameter obtained from a mixed effects model to minimize regression dilution bias. The associations between lipid variability and renal outcomes including incident kidney disease, renal function decline defined as ≥ 30% reduction in estimated glomerular filtration rate since baseline, and end-stage renal disease (estimated glomerular filtration rate < 15 mL/min/1.73 m2) were evaluated by multivariable Cox regression. After a median follow-up of 66.5 months (0.5 million person-years in total), 49,653 kidney disease, 29,358 renal function decline, and 1765 end-stage renal disease cases were recorded. Positive linear associations between low-density lipoprotein-cholesterol and total cholesterol to high-density lipoprotein-cholesterol ratio variabilities and the risk of all renal outcomes were demonstrated. However, no association between triglyceride variability and any outcome was found. Each mmol/L increase in low-density lipoprotein-cholesterol variability was associated with 20% (Hazard ratio 1.20 [95% CI 1.15-1.25]), 38% (Hazard ratio 1.37 [95% CI 1.30-1.45]), and 108% (Hazard ratio 2.08 [95% CI 1.74-2.50]) higher risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Similarly, each unit increase in total cholesterol to high-density lipoprotein-cholesterol ratio variability was associated with 35% (Hazard ratio 1.15 [95% CI 1.10-1.20]), 33% (Hazard ratio 1.33 [95% CI 1.26-1.40]), and 75% (Hazard ratio 1.75 [95% CI 1.46-2.09]) heightened risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Cholesterol variability may potentially be a useful predictor of kidney diseases in patients with type 2 diabetes mellitus. Attention should be drawn to cholesterol variability when managing diabetic patients and further research is warranted to investigate the modifiable risk factors for lipid variability.

Nephrology and Palliative Care Collaboration in the Care of Patients With Advanced Kidney Disease: Results of a Clinician Survey

Rationale & Objective

Despite calls for integrating palliative care into chronic kidney disease (CKD) care, uptake remains low. The study aim was to describe clinicians’ perceptions of the clinical and research priorities in CKD care and the main barriers to collaboration.

Study Design

This was a descriptive cross-sectional study using an online survey developed by clinicians and researchers as the primary data collection method.

Setting & Participants

Clinicians in nephrology and palliative care departments (N = 195) at an academic health center in Virginia were invited to participate. Of the 48.7% (n = 95) who responded, most were registered nurses (65.3%) in nephrology (80%) with more than 15 years’ experience (40%).

Predictors

Factors including discipline (nursing, social work, and physician) and practice area (palliative care or nephrology) were assessed.

Outcomes

Main outcomes of interest included clinicians’ perceptions of the role of palliative care, barriers to collaboration, and the top clinical and research priorities for patients with advanced CKD.

Analytic Approach

Survey data were analyzed using SPSS using descriptive statistics.

Results

Respondents reported being comfortable caring for patients near the end of life and endorsed advance care planning and collaboration between nephrology and palliative care teams. However, both rarely happen. Fragmentation, or poor coordination of care, was perceived to be the main barrier to collaboration. Perceptions regarding collaboration facilitation differed; nephrology clinicians identified patient/family education as the most important facilitator while palliative care clinicians identified clinician education as most important. Top clinical priorities differed. Palliative care clinicians reported pain/symptom management as taking priority while nephrology clinicians identified caregiver/family support. Developing interventions to support treatment-related decision making was the top research priority.

Limitations

Results reflect perceptions of about half the clinicians at 1 academic health center.

Conclusions

Additional studies to capture patients’ and families’ perspectives and examine end-of-life care processes are needed. Results may inform future targeted interventions.

Microbial genetic and transcriptional contributions to oxalate degradation by the gut microbiota in health and disease

Over-accumulation of oxalate in humans may lead to nephrolithiasis and nephrocalcinosis. Humans lack endogenous oxalate degradation pathways (ODP), but intestinal microbes can degrade oxalate using multiple ODPs and protect against its absorption. The exact oxalate-degrading taxa in the human microbiota and their ODP have not been described. We leverage multi-omics data (>3000 samples from >1000 subjects) to show that the human microbiota primarily uses the type II ODP, rather than type I. Furthermore, among the diverse ODP-encoding microbes, an oxalate autotroph, Oxalobacter formigenes, dominates this function transcriptionally. Patients with inflammatory bowel disease (IBD) frequently suffer from disrupted oxalate homeostasis and calcium oxalate nephrolithiasis. We show that the enteric oxalate level is elevated in IBD patients, with highest levels in Crohn's disease (CD) patients with both ileal and colonic involvement consistent with known nephrolithiasis risk. We show that the microbiota ODP expression is reduced in IBD patients, which may contribute to the disrupted oxalate homeostasis. The specific changes in ODP expression by several important taxa suggest that they play distinct roles in IBD-induced nephrolithiasis risk. Lastly, we colonize mice that are maintained in the gnotobiotic facility with O. formigenes, using either a laboratory isolate or an isolate we cultured from human stools, and observed a significant reduction in host fecal and urine oxalate levels, supporting our in silico prediction of the importance of the microbiome, particularly O. formigenes in host oxalate homeostasis.

Combination of polycarboxybetaine coating and factor XII inhibitor reduces clot formation while preserving normal tissue coagulation during extracorporeal life support

Blood contact with high surface area medical devices, such as dialysis and extracorporeal life support (ECLS), induces rapid surface coagulation. Systemic anticoagulation, such as heparin, is thus necessary to slow clot formation, but some patients suffer from bleeding complications. Both problems might be reduced by 1) replacing heparin anticoagulation with artificial surface inhibition of the protein adsorption that initiates coagulation and 2) selective inhibition of the intrinsic branch of the coagulation cascade. This approach was evaluated by comparing clot formation and bleeding times during short-term ECLS using zwitterionic polycarboxybetaine (PCB) surface coatings combined with either a potent, selective, bicyclic peptide inhibitor of activated Factor XII (FXII900) or standard heparin anticoagulation. Rabbits underwent venovenous ECLS with small sham oxygenators for 60 min using three means of anticoagulation (n = 4 ea): (1) PCB coating + FXII900 infusion, (2) PCB coating + heparin infusion with an activated clotting time of 220-300s, and (3) heparin infusion alone. Sham oxygenator blood clot weights in the PCB + FXII900 and PCB + heparin groups were 4% and 25% of that in the heparin group (p < 10^-6 and p < 10^-5), respectively. At the same time, the bleeding time remained normal in the PCB + FXII900 group (2.4 ± 0.2 min) but increased to 4.8 ± 0.5 and 5.1 ± 0.7 min in the PCB + heparin and heparin alone groups (p < 10^-4 and 0.01). Sham oxygenator blood flow resistance was significantly lower in the PCB + FXII900 and PCB + heparin groups than in the heparin only group (p < 10^-6 and 10^-5). These results were confirmed by gross and scanning electron microscopy (SEM) images and fibrinopeptide A (FPA) concentrations. Thus, the combined use of PCB coating and FXII900 markedly reduced sham oxygenator coagulation and tissue bleeding times versus the clinical standard of heparin anticoagulation and is a promising anticoagulation method for clinical ECLS.

A dose-escalating toxicology study of the candidate biologic ELP-VEGF

Vascular Endothelial Growth Factor (VEGF), a key mediator of angiogenesis and vascular repair, is reduced in chronic ischemic renal diseases, leading to microvascular rarefaction and deterioration of renal function. We developed a chimeric fusion of human VEGF-A₁₂₁ with the carrier protein Elastin-like Polypeptide (ELP-VEGF) to induce therapeutic angiogenesis via targeted renal VEGF therapy. We previously showed that ELP-VEGF improves renal vascular density, renal fibrosis, and renal function in swine models of chronic renal diseases. However, VEGF is a potent cytokine that induces angiogenesis and increases vascular permeability, which could cause undesired off-target effects or be deleterious in a patient with a solid tumor. Therefore, the current study aims to define the toxicological profile of ELP-VEGF and assess its risk for exacerbating tumor progression and vascularity using rodent models. A dose escalating toxicology assessment of ELP-VEGF was performed by administering a bolus intravenous injection at doses ranging from 0.1 to 200 mg/kg in Sprague Dawley (SD) rats. Blood pressure, body weight, and glomerular filtration rate (GFR) were quantified longitudinally, and terminal blood sampling and renal vascular density measurements were made 14 days after treatment. Additionally, the effects of a single administration of ELP-VEGF (0.1-10 mg/kg) on tumor growth rate, mass, and vascular density were examined in a mouse model of breast cancer. At doses up to 200 mg/kg, ELP-VEGF had no effect on body weight, caused no changes in plasma or urinary markers of renal injury, and did not induce renal fibrosis or other histopathological findings in SD rats. At the highest doses (100-200 mg/kg), ELP-VEGF caused an acute, transient hypotension (30 min), increased GFR, and reduced renal microvascular density 14 days after injection. In a mouse tumor model, ELP-VEGF did not affect tumor growth rate or tumor mass, but analysis of tumor vascular density by micro-computed tomography (μCT) revealed significant, dose dependent increases in tumor vascularity after ELP-VEGF administration. ELP-VEGF did not induce toxicity in the therapeutic dosing range, and doses one hundred times higher than the expected maximum therapeutic dose were needed to observe any adverse signs in rats. In breast tumor-bearing mice, ELP-VEGF therapy induced a dose-dependent increase in tumor vascularity, demanding caution for potential use in a patient suffering from kidney disease but with known or suspected malignancy.

Differences between diabetic and non-diabetic nephropathy patients in cardiac structure and function at the beginning of hemodialysis and their impact on the prediction of mortality

OBJECTIVES

To characterize differences in cardiac structure and function in hemodialysis (HD) patients with diabetic nephropathy (DN) and in those without using echocardiography and to determine their impact on the prediction of mortality using echocardiographic parameters.

METHODS

Clinical, laboratory, and echocardiographic data were collected from patients commencing HD.

RESULTS

Compared with those without DN, patients with DN had lower peak velocity of the early diastolic wave (e'), larger left atria, and higher peak early diastolic velocity (E)/e' and peak velocity of tricuspid regurgitation (TR). In addition, a larger proportion of DN patients had a combination of left ventricular (LV) diastolic dysfunction, cardiac valve calcification, moderate-to-severe cardiac valve regurgitation (CVR), and at least moderate pericardial effusion (PE). After accounting for age, sex, smoking, hypertension, hemoglobin, and albumin, DN was responsible for e'  < 10 cm/s, E/e' >13 m/s, TR >2.8 m/s, LV diastolic dysfunction, CVR, and PE. LV diastolic dysfunction and E/e' >13 were the most useful predictors of mortality in patients with DN.

CONCLUSIONS

Patients with DN who undergo HD tend to have worse LV diastolic function and are more likely to have heart valve problems. LV diastolic dysfunction and E/e' are predictors of death in DN patients.

Development and Validation of a Chronic Kidney Disease Prediction Model for Type 2 Diabetes Mellitus in Thailand

OBJECTIVES

The objective of this study was to investigate predictors and develop risk equations for stage-3 chronic kidney disease (CKD) in Thai patients with type 2 diabetes mellitus (DM).

METHODS

A retrospective cohort study was conducted in patients with type 2 DM. The outcome was the development of stage-3 CKD. The data set was randomly split into training and validation data sets. Cox proportional hazard regression was used for model development. Discrimination (Harrell's C statistic) and calibration (the Hosmer-Lemeshow chi-square test and survival probability curve) were applied to evaluate model performance.

RESULTS

In total, 2178 type 2 DM patients without stage-3 CKD, visiting the hospital from January 1, 2008, to December 31, 2017, were recruited, with median follow-up time of 1.29 years (interquartile range, 0.5-2.5 years); 385 (17.68%) subjects had developed stage-3 CKD. The final predictors included age, male sex, urinary albumin to creatinine ratio, estimated glomerular filtration rate, and hemoglobin A1c. Two 3-year stage-3 CKD risk models, model 1 (laboratory model) and model 2 (simplified model), had the C statistic in validation data sets of 0.890 and 0.812, respectively.

CONCLUSIONS

Two 3-year stage-3 CKD risk models were developed for Thai patients with type 2 DM. Both models have good discrimination and calibration. These stage-3 CKD prediction models could equip health providers with tools for clinical management and supporting patient education.

Inhibition of T-Cells by Cyclosporine A Reduces Macrophage Accumulation to Regulate Venous Adaptive Remodeling and Increase Arteriovenous Fistula Maturation

OBJECTIVE

Arteriovenous fistulae (AVF) are the preferred vascular access for hemodialysis, but the primary success rate of AVF remains poor. Successful AVF maturation requires vascular wall thickening and outward remodeling. A key factor determining successful AVF maturation is inflammation that is characterized by accumulation of both T-cells and macrophages. We have previously shown that anti-inflammatory (M2) macrophages are critically important for vascular wall thickening during venous remodeling; therefore, regulation of macrophage accumulation may be an important mechanism promoting AVF maturation. Since CD4+ T-cells such as T-helper type 1 cells, T-helper type 2 cells, and regulatory T-cells can induce macrophage migration, proliferation, and polarization, we hypothesized that CD4+ T-cells regulate macrophage accumulation to promote AVF maturation. Approach and Results: In a mouse aortocaval fistula model, T-cells temporally precede macrophages in the remodeling AVF wall. CsA (cyclosporine A; 5 mg/kg, sq, daily) or vehicle (5% dimethyl sulfoxide) was administered to inhibit T-cell function during venous remodeling. CsA reduced the numbers of T-helper type 1 cells, T-helper type 2, and regulatory T-cells, as well as M1- and M2-macrophage accumulation in the wall of the remodeling fistula; these effects were associated with reduced vascular wall thickening and increased outward remodeling in wild-type mice. However, these effects were eliminated in nude mice, showing that the effects of CsA on macrophage accumulation and adaptive venous remodeling are T-cell-dependent.

CONCLUSIONS

T-cells regulate macrophage accumulation in the maturing venous wall to control adaptive remodeling. Regulation of T-cells during AVF maturation may be a strategy that can improve AVF maturation. Graphic Abstract: A graphic abstract is available for this article.

Comparison of shared decision making in patients undergoing hemodialysis and peritoneal dialysis for choosing a dialysis modality

Background

Shared decision making (SDM) is recognized as the gold standard for patient-centered care. This study aimed to assess and compare the SDM among patients undergoing hemodialysis and peritoneal dialysis for choosing a dialysis modality.

Methods

This is a cross-sectional study that was performed on 300 dialysis patients (218 HD and 82 PD) referred to two Dialysis Centers. Data were collected using demographic information and a 9-item Shared Decision Making Questionnaire (SDM-Q-9). The data were analyzed using ANOVA and independent t-test by SPSS software.

Results

The mean SDM-Q-9 score in all samples (PD and HD) was 21.94 ± 15.08 (in a possible range of 0 to 45). Results of the independent t-test showed that the mean SDM-Q-9 score in PD patients (33.11 ± 10.08) was higher than HD patients (17.14 ± 74.24) (p < 0.001). The results showed a statistically significant difference in mean SDM-Q-9 score based on patients’ age, educational level, and income (p < 0.05).

Conclusion

Implementing shared decision making and providing information on RRT should be started in the early stage of CKD. The health care providers should involve patients with CKD and their families in dialysis-related decisions and it should be started in the early stage of CKD.

Association between anemia and mortality in hemodialysis patients is modified by the presence of diabetes

BACKGROUND

The prevalence and severity of anemia differ between diabetic and non-diabetic patients. We investigated whether the effect of hemoglobin (Hb) on patient outcome was affected by the presence or absence of diabetes among Japanese patients receiving chronic hemodialysis (HD).

METHODS

We enrolled 149,308 patients from a nationwide dialysis registry in Japan at the end of 2012 (mean age, 67.6 ± 12.3 years; male, 61.7%; diabetes, 43.5%; median dialysis duration, 65 months) who underwent three HD sessions weekly. One-year all-cause and cardiovascular (CV) mortality were assessed using Cox regression analysis and competing-risks regression analysis. We used multiple imputation to deal with missing covariate data.

RESULTS

Baseline Hb and serum ferritin levels were independently associated with all-cause and CV mortality. In non-diabetic patients, a significantly higher risk for all-cause mortality compared to the reference group (10 to 11 g/dL) was observed in patients with Hb < 8 g/dL (hazard ratio (HR): 1.266; 95% confidence interval (CI) 1.097-1.460) and 8 to  9 g/dL(HR: 1.153; 95% CI 1.030-1.290). On the other hand, diabetic HD patients in the same Hb category group did not have increased risk of all-cause mortality.

CONCLUSIONS

We found that non-diabetic HD patients had an increased risk of all-cause mortality if they had lower Hb levels, whereas the effect of Hb levels on mortality was attenuated in diabetic HD patients. These data suggest that the association between Hb levels and mortality rate could be different between diabetic and non-diabetic HD patients.

Procalcitonin as a Marker of Comorbid Atrial Fibrillation in Chronic Kidney Disease and History of Sepsis

Cardiovascular disease and infection are the leading causes of mortality in patients with stage 5 chronic kidney disease on hemodialysis (CKD5-HD). Inflammation is a large component in the pathogenesis of both atrial fibrillation (AF) and sepsis and may link these conditions in CKD5-HD. Procalcitonin (PCT) is an inflammatory biomarker elevated in systemic infection and CKD5-HD, yet its value with regard to comorbid AF has not been thoroughly investigated. The aim of this study sought to evaluate circulating inflammatory markers, including PCT, Angiopoietin-1, Angiopoetin-2, CD40-L, C-reactive protein, d-dimer, and von Willebrand factor in relation to these conditions. Plasma levels of inflammatory markers were measured by enzyme linked immunosorbent assay method in CKD5-HD (n = 97) patients and controls (n = 50). Procalcitonin levels were significantly elevated (P = .0270) in CKD5-HD with comorbid AF compared to those without AF. Further analysis of patients with a history of sepsis demonstrated significantly elevated levels of PCT (P = .0405) in those with comorbid AF (160.7 ± 39.5 pg/mL) compared to those without AF (117.4 ± 25.3 pg/mL). This study demonstrates that the inflammatory biomarker PCT is further elevated in the presence of both AF and a history of sepsis in hemodialysis patients and suggests that underlying chronic inflammation following sepsis resolution may place these patients at greater risk of developing AF.

Chronic elevation of cardiac troponin I predicts the extent of coronary disease in hemodialysis patients presenting with acute enzyme elevation

Introduction

Elevation of cardiac troponin I (cTn-I) is associated with coronary artery disease (CAD) in asymptomatic patients with end-stage renal disease (ESRD) receiving hemodialysis. We aim to investigate the diagnostic value of chronically elevated cTn-I in ESRD patients presenting with an acute rise in serum cTn-I levels.

Methods

We performed a retrospective analysis of 364 patients. Using coronary angiography, we correlated baseline elevation of cTn-I with the severity of CAD when hemodialysis patients present with acute symptomatic elevation in serum cTn-I.

Results

In hemodialysis patients presenting with a rise in serum cTn-I above baseline levels, 59% had severe CAD, and 17% had no angiographic evidence of CAD. Hemodialysis patients with severe CAD had significantly higher baseline cTn-I levels compared to patients with non-severe CAD or normal coronaries (p < 0.0001). Baseline elevation of cTn-I in the severe CAD group was correlated with the degree of CAD occlusion (r2 0.56, p < 0.0001), fitting a positive linear model. Furthermore, baseline cTn-I differentiates between patients with and without severe CAD with a test accuracy of 0.72 (95% CI, 0.69-0.75, p < 0.001). At a value of ≥0.2 ng/mL (cutoff for myocardial necrosis), the specificity of baseline cTn-I for underlying severe CAD was 0.95.

Conclusions

Elevated baseline cTn-I has good accuracy for anticipating more advanced angiographic CAD when hemodialysis patients present with a symptomatic rise in serum cTn-I above baseline levels. Baseline elevation of cTn-I can be used for cardiac disease risk management in hemodialysis patients presenting with symptoms suggestive of CAD.

Dipeptidyl peptidase 4 promotes peritoneal fibrosis and its inhibitions prevent failure of peritoneal dialysis

Peritoneal dialysis (PD) possesses multiple advantages for end stage renal disease. However, long-term PD triggers peritoneal fibrosis (PF). From the nationwide analysis of diabetic PD patients (n = 19,828), we identified the incidence of PD failure was significantly lower in diabetic patients treated with dipeptidyl peptidase 4 (DPP4) inhibitors. Experimental study further showed high concentration of glucose remarkably enhanced DPP4 to promote epithelial-mesenchymal transition (EMT) in the mesothelial cells. In chlorhexidine gluconate (CG)-induced PF model of rats, DPP4 expression was enriched at thickening peritoneum. Moreover, as to CG-induced PF model, DPP4 deficiency (F344/DuCrlCrlj strain), sitagliptin and exendin-4 treatments significantly inhibited DPP4 to reverse the EMT process, angiogenesis, oxidative stress, and inflammation, resulting in the protection from PF, preservation of peritoneum and the corresponding functional integrity. Furthermore, DPP4 activity was significantly correlated with peritoneal dysfunction. Taken together, DPP4 caused peritoneal dysfunction/PF, whereas inhibition of DPP4 protected the PD patients against PD failure.

Prognostic Value of Soluble Suppression of Tumorigenicity 2 in Chronic Kidney Disease Patients: A Meta-Analysis

Objective

Previous studies have controversial results about the prognostic role of soluble suppression of tumorigenicity 2 (sST2) in chronic kidney disease (CKD). Therefore, we conduct this meta-analysis to access the association between sST2 and all-cause mortality, cardiovascular disease (CVD) mortality, and CVD events in patients with CKD.

Methods

The publication studies on the association of sST2 with all-cause mortality, CVD mortality, and CVD events from PubMed and Embase were searched through August 2020. We pooled the hazard ratio (HR) comparing high versus low levels of sST2 and subgroup analysis based on treatment, continent, and diabetes mellitus (DM) proportion, and sample size was also performed.

Results

There were 15 eligible studies with 11,063 CKD patients that were included in our meta-analysis. Elevated level of sST2 was associated with increased risk of all-cause mortality (HR 2.05; 95% confidence interval (CI), 1.51-2.78), CVD mortality (HR 1.68; 95% CI, 1.35-2.09), total CVD events (HR 1.88; 95% CI, 1.26-2.80), and HF (HR 1.35; 95% CI, 1.11-1.64). Subgroup analysis based on continent, DM percentage, and sample size showed that these factors did not influence the prognostic role of sST2 levels to all-cause mortality.

Conclusions

Our results show that high levels of sST2 could predict the all-cause mortality, CVD mortality, and CVD events in CKD patients.

Music-based interventions for pain relief in patients undergoing hemodialysis: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Music therapy and music-based interventions have been used widely in numerous medical procedures to reduce the physical and psychological disorders. However, the effect of music therapy on pain relief in hemodialysis patients still remains unclear.

METHODS

Electronic databases were comprehensively searched through MEDLINE, Web of Science, EMBASE, Cochrane, and WANFANG. All studies met inclusion criteria were eligible for systematic review and meta-analysis. Clinical variables were extracted and pooled results were obtained using STATA software.

RESULTS

A total of 10 studies with 722 participants were included for systematic review. Overall, music therapy showed a significantly favorable effect on reducing pain for patients undergoing hemodialysis (SMD: -0.90, 95%CIs: -1.25 to -0.55, P < .001). No publication bias was observed.

CONCLUSIONS

Music-based interventions could significantly relieve pain for patients undergoing hemodialysis, which should be promoted as an effective and safe complementary method.

Relationships between resilience, empathy, compassion fatigue, work engagement and turnover intention in haemodialysis nurses: A cross-sectional study

AIM

To explore the relationships between resilience, empathy, compassion fatigue, work engagement and turnover intention in Chinese haemodialysis nurses.

BACKGROUND

Although several studies explored nurses' turnover intention in multiple hospital wards, fewer studies focused on turnover intention and its predictors among nurses in dialysis care.

METHODS

We conducted a cross-sectional study and adopted a two-stage sampling method to recruit 528 Chinese haemodialysis nurses. Multiple regression analysis was performed to explore the effects of resilience, empathy, compassion fatigue and work engagement on turnover intention.

RESULTS

The prevalence of high and exceptionally high levels of turnover intention was 59.1% and 9.0%. Compassion fatigue had the strongest significant effect on turnover intention (β = 0.276), followed by work engagement (β = -0.256) and resilience (β = 0.193). Haemodialysis nurses in tertiary hospitals reported significant higher levels of turnover intention than those in secondary hospitals (β = 0.127).

CONCLUSIONS

Higher levels of compassion fatigue and lower levels of resilience and work engagement can result in higher turnover intention in haemodialysis nurses.

IMPLICATIONS FOR NURSING MANAGEMENT

Strategies such as resilience training programme, mindfulness-based intervention and establishing a positive work environment may be effective methods to improve resilience, reduce compassion fatigue, promote work engagement and decrease turnover intention.

Diabetes, Hypertension, and Incidence of Chronic Kidney Disease: Is There any Multiplicative or Additive Interaction?

BACKGROUND

The burden of chronic kidney disease (CKD) is on the rise worldwide; diabetes and hypertension are mentioned as the main contributors.

OBJECTIVES

The current study aimed to investigate the multiplicative and additive interaction of diabetes and hypertension in the incidence of CKD.

METHODS

In this population-based cohort study, 7342 subjects aged 20 years or above (46.8% male) were divided into four groups: no diabetes and hypertension; diabetes and no hypertension; hypertension and no diabetes; and both diabetes and hypertension. The multivariable Cox regression was used to determine the effect of diabetes, hypertension, and their multiplicative interaction on CKD. The following indices were used to determine the additive interaction of diabetes and hypertension: the relative excess risk of interaction, the attributable proportion due to interaction, and the synergism index.

RESULTS

Diabetes and hypertension had no significant multiplicative interaction in men (hazard ratio of 0.93, P value: 0.764) and women (hazard ratio of 0.79, P value: 0.198); furthermore, no additive interaction was found in men (relative excess risk due to interaction of 0.79, P value: 0.199; attributable proportion due to interaction of 0.22, P value: 0.130; synergy index of 1.44, P value: 0.183) and women (relative excess risk due to interaction of -0.26, P value: 0.233, attributable proportion due to interaction of -0.21, P value: 0.266; synergy index of 0.48, P value: 0.254).

CONCLUSIONS

This study demonstrated no synergic effect between diabetes and hypertension on the incidence of CKD.

High Circulating Follicle-Stimulating Hormone Level Is a Potential Risk Factor for Renal Dysfunction in Post-Menopausal Women

OBJECTIVE

Menopause contributes to renal dysfunction in women, which is generally attributed to estrogen withdrawal. In addition to decreased estrogen level, serum follicle-stimulating hormone (FSH) level increases after menopause. This study investigated the association between high circulating FSH level and renal function in post-menopausal women.

METHODS

This observational cross-sectional study included 624 pre-menopausal, 121 peri-menopausal, and 2540 post-menopausal women. The levels of female sex hormones were examined by chemiluminescence and indices of renal function were measured using a clinical chemistry analyzer. The post-menopausal women were grouped into quartiles according to serum FSH levels.

RESULTS

Renal function progressively declined from pre-menopause to peri-menopause to post-menopause, which was accompanied by increasing serum FSH level. In post-menopausal women, serum creatinine level increased with increasing FSH quartile, which was accompanied by a decrease in estimated glomerular filtration rate (eGFR) (p for trend <0.001); moreover, the prevalence of declined eGFR (<90 ml/min/1.73 m²) and chronic kidney disease (CKD; eGFR <60 ml/min/1.73 m²) increased (p for trend <0.001). Even after adjusting for confounders, the odds ratios (ORs) of declined eGFR and CKD increased with increasing FSH quartiles in post-menopausal women. The ORs of declined eGFR (OR=2.19, 95% confidence interval [CI]: 1.63-2.92) and CKD (OR=10.09, 95% CI: 2.28-44.65) in the highest FSH quartile were approximately 2- and 10-fold higher, respectively, than in the lowest FSH quartile (p<0.05). After stratifying post-menopausal women by median age (61 years), the OR for declined eGFR for each FSH quartile in the older group was higher than that for the corresponding FSH quartile in the younger group.

CONCLUSIONS

A high circulating FSH level is an independent risk factor for renal dysfunction in women after menopause. Additionally, aging may aggravate the association of high FSH levels with reduced renal function in post-menopausal women.