US Renal Data System 2018 Annual Data Report: Epidemiology of Kidney Disease in the United States

Comprehensive review of current management guidelines of chronic kidney disease

Chronic kidney disease (CKD) is a prevalent and progressive condition affecting millions worldwide. It is a long-term condition characterized by gradual loss of kidney function over time. The management of CKD is complex and requires a multidisciplinary approach. This review aims to outline the current management guidelines for CKD. The study included a comprehensive search of various PubMed, Embase, and the Cochrane Library databases for articles published between 2010 and 2023. The search terms used were "chronic kidney disease," "management," and "guidelines." The inclusion criteria were articles that provided management guidelines for patients with CKD. A total of 23 articles were included in the review. Most articles were based on the Kidney Disease Improving Global Outcomes guidelines, the most widely recognized and used guidelines for managing CKD. The study found that the guidelines emphasize the importance of early detection and management of CKD and the need for an approach that involves multiple disciplines in its management. The guidelines recommend several interventions to slow the progression of CKD, including blood pressure control, glycemic control in diabetic patients, and reduce proteinuria. Other interventions include lifestyle modifications such as dietary changes, physical activity, and smoking cessation. The guidelines also recommend regular monitoring of kidney function and referral to a nephrologist for patients with advanced CKD or other complications. Overall, the current management guidelines for CKD emphasize the importance of early detection and a multidisciplinary approach to its management.

Hybrid Method for Peritoneal Dialysis Catheter Insertion: A New Technique for Improved Outcomes and Reduced Costs

INTRODUCTION

Peritoneal dialysis (PD) is a well-established treatment choice for end-stage kidney disease (ESKD). While there are several methods for PD catheter insertion, they each have limitations. In this study, we present a new hybrid method for PD catheter insertion and compare it to the conventional laparoscopic method.

METHODS

This retrospective study included 171 patients who were undergoing their first PD catheter insertion, and a total of 20% of the enrolled patients had a past medical history of abdominal surgery. Out of these, 101 patients underwent the laparoscopic method and 70 underwent a new invented hybrid method. The study aimed to compare the surgical outcomes, incidence of early and late complications, hospital stay, and medical expenses between the two groups.

RESULTS

There were no notable differences in basic demographic features and comorbid conditions between the two groups. The results of our data revealed that the hybrid group had a significantly shorter break-in period and did not require temporary hemodialysis. Additionally, length of hospital stay and medical costs were significantly lower in the hybrid group (all p < 0.05). The incidence of early complications was lower in the hybrid group, while the incidence of late complications was comparable between the two groups.

CONCLUSION

Our study demonstrates that the hybrid method of PD catheter insertion provides a safe and efficient alternative to the traditional laparoscopic method, enabling urgent-start PD and reducing hospital stays and medical expenses. Our findings support the use of the hybrid method as a new standard of care for ESKD patients undergoing PD catheter insertion.

Evolution of kidney allograft loss causes over 40 years (1979-2019)

INTRODUCTION

The improvement of kidney allograft recipient and graft survival showed a decrease over the last 40 years. Long-term graft loss rate remained stable during a 25-year time span. Knowing the changing causes and the risk factors associated with graft loss requires special attention. The present study aimed to assess the causes of graft loss and kidney allograft recipient death. Also, we aimed to compare two different periods (1979-1999 and 2000-2019) to identify changes in the characteristics of the failed allografts and recipient and donors profile.

METHODS AND PATIENTS

We performed a single-center cohort study. We included all the kidney transplant recipients at the Hospital del Mar (Barcelona) between May 1979 and December 2019. Graft loss was defined as recipient death with functioning graft and as loss of graft function (return to dialysis or retransplantation). We assessed the causes of graft loss using clinical and histological information. We also analyzed the results of the two different transplant periods (1979-1999 and 2000-2019).

RESULTS

Between 1979 and 2019, 1522 transplants were performed. The median follow-up time was 56 (IQR 8-123) months. During follow-up, 722 (47.5%) grafts were lost: 483 (66.9%) due to graft failure and 239 (33.1%) due to death with functioning graft. The main causes of death were cardiovascular (25.1%), neoplasms (25.1%), and infectious diseases (21.8%). These causes were stable between the two periods of time. Only the unknown cause of death has decreased in the last period. The main cause of graft failure (loss of graft function) was the allograft chronic dysfunction (75%). When histologic information was available, antibody-mediated rejection (ABMR) and interstitial fibrosis/tubular atrophy (IF/TA) were the most frequent specific causes (15.9% and 12.6%). Of the graft failures, 213 (29.5%) were early (<1 year of transplantation). Vascular thrombosis was the main cause of early graft failure in the second period (2000-2019) (46.7%) and T-cell-mediated rejection (TCMR) was the main cause (31.3%) in the first period (1979-1999). The causes of late graft loss were similar between the two periods.

CONCLUSIONS

The causes of kidney allograft recipient death are still due to cardiovascular and malignant diseases. Vascular thrombosis has emerged as a frequent cause of early graft loss in the most recent years. The evaluation of the causes of graft loss is necessary to improve kidney transplantation outcomes.

Unraveling the Crosstalk between Lipids and NADPH Oxidases in Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a serious complication of diabetes mellitus and a leading cause of end-stage renal disease. Abnormal lipid metabolism and intrarenal accumulation of lipids have been shown to be strongly correlated with the development and progression of diabetic kidney disease (DKD). Cholesterol, phospholipids, triglycerides, fatty acids, and sphingolipids are among the lipids that are altered in DKD, and their renal accumulation has been linked to the pathogenesis of the disease. In addition, NADPH oxidase-induced production of reactive oxygen species (ROS) plays a critical role in the development of DKD. Several types of lipids have been found to be tightly linked to NADPH oxidase-induced ROS production. This review aims to explore the interplay between lipids and NADPH oxidases in order to provide new insights into the pathogenesis of DKD and identify more effective targeted therapies for the disease.

Associated factors of cardiac valve calcification and its prognostic effects among patients with chronic kidney disease: a systematic review and meta-analysis

Background

Cardiac valve calcification (CVC) is highly prevalent and a risk factor for adverse outcomes in patients with chronic kidney disease (CKD). This meta-analysis aimed to investigate the risk factors for CVC and association between CVC and mortality in CKD patients.

Method

Three electronic databases including PubMed, Embase, and Web of Science were searched for relevant studies up to November 2022. Hazard ratios (HR), odds ratios (OR), and 95% confidence intervals (CI) were pooled using random-effect meta-analyses.

Results

22 studies were included in the meta-analysis. Pooled analyses showed that CKD patients with CVC were relatively older, had a higher body mass index, left atrial dimension, C-reaction protein level, and a declined ejection fraction. Calcium and phosphate metabolism dysfunction, diabetes, coronary heart disease, and duration of dialysis were all predictors for CVC in CKD patients. The presence of CVC (both aortic valve and mitral valve) increased the risk of all-cause and cardiovascular mortality in CKD patients. However, the prognostic value of CVC for mortality was not significant anymore in patients with peritoneal dialysis.

Conclusion

CKD patients with CVC had a greater risk of all-cause and cardiovascular mortality. Multiple associated factors for development of CVC in CKD patients should be taken into consideration by healthcare professionals to improve prognosis.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier [CRD42022364970].

Evaluation of Renal Fibrosis Using Magnetization Transfer Imaging at 1.5T and 3T in a Porcine Model of Renal Artery Stenosis

Renal fibrosis is an important marker in the progression of chronic kidney disease, and renal biopsy is the current reference standard for detecting its presence. Currently, non-invasive methods have only been partially successful in detecting renal fibrosis. Magnetization transfer imaging (MTI) allows estimates of renal fibrosis but may vary with scanning conditions. We hypothesized that MTI-derived renal fibrosis would be reproducible at 1.5T and 3T MRI and over time in fibrotic kidneys. Fifteen pigs with unilateral renal artery stenosis (RAS, n = 9) or age-matched sham controls (n = 6) underwent MTI-MRI at both 1.5T and 3T 6 weeks post-surgery and again 4 weeks later. Magnetization transfer ratio (MTR) measurements of fibrosis in both kidneys were compared between 1.5T and 3T, and the reproducibility of MTI at the two timepoints was evaluated at 1.5T and 3T. MTR at 3T with 600 Hz offset frequency successfully distinguished between normal, stenotic, and contralateral kidneys. There was excellent reproducibility of MTI at 1.5T and 3T over the two timepoints and no significant differences between MTR measurements at 1.5T and 3T. Therefore, MTI is a highly reproducible technique which is sensitive to detect changes in fibrotic compared to normal kidneys in the RAS porcine model at 3T.

Prospective associations of health literacy with clinical outcomes in adults with CKD: findings from the CRIC study

BACKGROUND

Limited health literacy is associated with significant morbidity and mortality in the general population but the relation of health literacy with long-term clinical outcomes among adults with chronic kidney disease (CKD) is less clear.

METHODS

Prospective data from the Chronic Renal Insufficiency Cohort (CRIC) Study (n = 3715) were used. Health literacy was assessed with the Short Test of Functional Health Literacy in Adults (dichotomized as limited/adequate). Cox proportional hazards models were used to separately examine the relations of health literacy with CKD progression, cardiovascular event (any of the following: myocardial infarction, congestive heart failure, stroke or peripheral artery disease), and all-cause, cardiovascular and non-cardiovascular mortality. Poisson regression was used to assess the health literacy-hospitalization association. Models were sequentially adjusted: Model 1 adjusted for potential confounders (sociodemographic factors), while Model 2 additionally adjusted for potential mediators (clinical and lifestyle factors) of the associations of interest.

RESULTS

In confounder-adjusted models, participants with limited (vs adequate) health literacy [555 (15%)] had an increased risk of CKD progression [hazard ratio (HR) 1.34; 95% confidence interval (CI) 1.06-1.71], cardiovascular event (HR 1.67; 95% CI 1.39-2.00), hospitalization (rate ratio 1.33; 95% CI 1.26-1.40), and all-cause (HR 1.54; 95% CI 1.27-1.86), cardiovascular (HR 2.39; 95% CI 1.69-3.38) and non-cardiovascular (HR 1.27; 95% CI 1.01-1.60) mortality. Additional adjustments for potential mediators (Model 2) showed similar results except that the relations of health literacy with CKD progression and non-cardiovascular mortality were no longer statistically significant.

CONCLUSIONS

In the CRIC Study, adults with limited (vs adequate) health literacy had a higher risk for CKD progression, cardiovascular event, hospitalization and mortality-regardless of adjustment for potential confounders.

Development and validation of a nomogram for predicting in-hospital mortality of elderly patients with persistent sepsis-associated acute kidney injury in intensive care units: a retrospective cohort study using the MIMIC-IV database

OBJECTIVES

To identify the clinical risk factors that influence in-hospital mortality in elderly patients with persistent sepsis-associated acute kidney injury (S-AKI) and to establish and validate a nomogram to predict in-hospital mortality.

DESIGN

Retrospective cohort analysis.

SETTING

Data from critically ill patients at a US centre between 2008 and 2021 were extracted from the Medical Information Mart for Intensive Care (MIMIC)-IV database (V.1.0).

PARTICIPANTS

Data from 1519 patients with persistent S-AKI were extracted from the MIMIC-IV database.

PRIMARY OUTCOME

All-cause in-hospital death from persistent S-AKI.

RESULTS

Multiple logistic regression revealed that gender (OR 0.63, 95% CI 0.45-0.88), cancer (2.5, 1.69-3.71), respiratory rate (1.06, 1.01-1.12), AKI stage (2.01, 1.24-3.24), blood urea nitrogen (1.01, 1.01-1.02), Glasgow Coma Scale score (0.75, 0.70-0.81), mechanical ventilation (1.57, 1.01-2.46) and continuous renal replacement therapy within 48 hours (9.97, 3.39-33.9) were independent risk factors for mortality from persistent S-AKI. The consistency indices of the prediction and the validation cohorts were 0.780 (95% CI: 0.75-0.82) and 0.80 (95% CI: 0.75-0.85), respectively. The model's calibration plot suggested excellent consistency between the predicted and actual probabilities.

CONCLUSIONS

This study's prediction model demonstrated good discrimination and calibration abilities to predict in-hospital mortality of elderly patients with persistent S-AKI, although it warrants further external validation to verify its accuracy and applicability.

Dual-modality and Noninvasive Diagnostic of MNP-PEG-Mn Nanoprobe for Renal Fibrosis Based on Photoacoustic and Magnetic Resonance Imaging

To date, imaging-guided multimodality therapy is important to improve the accuracy of the diagnosis of renal fibrosis, and nanoplatforms for imaging-guided multimodality diagnosis are gaining more and more attention. There are many limitations and deficiencies in clinical use for early-stage diagnosis of renal fibrosis, and multimodal imaging can contribute more thoroughly and provide in-detail information for effective clinical diagnosis. Melanin is an endogenous biomaterial, and we developed an ultrasmall particle size melanin nanoprobe (MNP-PEG-Mn) based on photoacoustic (PA) and magnetic resonance (MR) dual-modal imaging. MNP-PEG-Mn nanoprobe, with the average diameter about 2.7 nm, can be passively targeted for accumulation in the kidney, and it has excellent free radical scavenging and antioxidant abilities without further exacerbating renal fibrosis. Using the normal group signal as a control, the dual-modal imaging results showed that the MR imaging (MAI) and PA imaging (PAI) signals reached the strongest at 6 h when MNP-PEG-Mn entered the 7 day renal fibrosis group via the left vein of the tail end of the mice; however, the strength of the dual-modal imaging signal and the gradient of signal change were significantly weaker in the 28 day renal fibrosis group than in the 7 day renal fibrosis group and normal group. The phenomenon preliminarily indicates that as a PAI/MRI dual-modality contrast medium candidate, MNP-PEG-Mn has outstanding ability in clinical application potential.

The spectrum and changes of biopsy-proven kidney diseases in Chinese children

AIM

The study aimed to investigate the spectrum of biopsy-proven kidney disease in Chinese children.

METHODS

Records of children 0-17 years old who underwent native kidney biopsy from June 1st, 2013 to December 31st, 2018 in the national inpatients' database of China were analyzed. Biopsy-proven kidney diseases of different sex, age groups, and diagnosis, and the changing patterns of kidney disease compared with the previous study were analyzed.

RESULTS

A total of 21,311 patients from 232 hospitals with a median age of 11.34 years were included. Immunoglobulin A vasculitis with nephritis (IgAVN) was the most common pathological finding [29.17%, 95% confidence interval (confidence interval, CI) = 28.56-29.78], followed by IgA nephropathy (IgAN) (22.70%, 95% CI = 22.14-23.27). IgAN was the most common finding in patients with hematuria (60.75%, 95% CI = 58.83-62.65], proteinuria (33.43%, 95% CI = 30.54-36.42), and hematuria plus proteinuria (62.77%, 95% CI = 56.19-69.02). Minimal change disease was the most common finding (40.69%, 95% CI = 39.41-41.98) in nephrotic syndrome. The proportion of IgAVN in patients with biopsy-proven glomerular disease increased year by year during 2013-2018 (p for trend < 0.001) and was higher than that of 2004-2014 [29.41% (95% CI = 29.10-29.72) in 2013-2018 vs. 13.35% (95% CI = 12.97-13.73) 2004-2014, p < 0.001]. The proportion of hepatitis B virus associated nephritis during 2013-2018 was lower than that of  2004-2014 [0.44% (95% CI = 0.36-0.54) in 2013-2018 vs. 0.87% (95% CI = 0.67-1.10) in 2004-2014, p < 0.001].

CONCLUSIONS

IgAVN and IgAN were the most common types of pathological findings in children who underwent kidney biopsies from 2013 to 2018. The pathological spectrum of kidney biopsy changed over time.

Gut Microbiota-Targeted Interventions in the Management of Chronic Kidney Disease

Recent advances in microbiome research have informed the potential role of the gut microbiota in the regulation of metabolic, cardiovascular, and renal systems, and, when altered, in the pathogenesis of various cardiometabolic disorders, including chronic kidney disease (CKD). The improved understanding of gut dysbiosis in cardiometabolic pathologies in turn has led to a vigorous quest for developing therapeutic strategies. These therapeutic strategies aim to investigate whether interventions targeting gut dysbiosis can shift the microbiota toward eubiosis and if these shifts, in turn, translate into improvements in (or prevention of) CKD and its related complications, such as premature cardiovascular disease. Existing evidence suggests that multiple interventions (eg, plant-based diets; prebiotic, probiotic, and synbiotic supplementation; constipation treatment; fecal microbiota transplantation; and intestinal dialysis) might result in favorable modulation of the gut microbiota in patients with CKD, and thereby potentially contribute to improving clinical outcomes in these patients. In this review, we summarize the current understanding of the characteristics and roles of the gut microbiota in CKD and discuss the potential of emerging gut microbiota-targeted interventions in the management of CKD.

C-L Case Conference: Torsades de Pointes in a Patient With Lifelong Medical Trauma, COVID-19, Remdesivir, Citalopram, Quetiapine, and Hemodialysis

We present a case of Torsades de Pointes (TdP) in a patient with COVID-19 infection and multiple TdP risk factors including QT-interval prolongation, hemodialysis, bradycardia, and treatment with remdesivir, citalopram, and quetiapine. The case was complicated by post-resuscitation anxiety superimposed on a history of medical trauma since childhood. Top experts in the field of consultation-liaison psychiatry, trauma informed care, and cardiac electrophysiology provide perspectives on this case with a review of the literature. Key teaching topics include identification of TdP risk factors in patients with a complex illness; the necessity for prompt electrophysiology consultation in clinical scenarios with high risk for TdP; and the approach to patients with medical trauma using a trauma-informed lens. We highlight the contributions of COVID-19, the pharmacokinetics of QT-interval-prolonging psychotropic medications, the risks of hemodialysis, and the role of remdesivir-induced bradycardia in this first reported case of TdP in a patient treated with remdesivir.

Parathyroidectomy and Cinacalcet Use in Medicare-Insured Kidney Transplant Recipients

RATIONALE & OBJECTIVE

Posttransplant hyperparathyroidism is common, and treatment practices are poorly characterized. The goal of this study was to examine the incidence, associations, and outcomes of posttransplant parathyroidectomy and calcimimetic use in a cohort of Medicare-insured US kidney transplant recipients.

STUDY DESIGN

Retrospective observational cohort study.

SETTING & PARTICIPANTS

We used the US Renal Data System to extract demographic, clinical, and prescription data from Medicare Parts A, B, and D-insured patients who received their first kidney transplant in 2007-2013. We excluded patients with pretransplant parathyroidectomy.

PREDICTORS

Calendar year of transplantation and pretransplant patient characteristics.

OUTCOME

(1) Incidence of and secular trends in parathyroidectomy and cinacalcet use in the 3 years after transplant; (2) 90-day outcomes after posttransplant parathyroidectomy and cinacalcet initiation.

ANALYTICAL APPROACH

Temporal trends and pretransplant correlates of parathyroidectomy and cinacalcet use were assessed using proportional hazards models and multivariable Poisson regression, respectively.

RESULTS

The inclusion criteria were met by 30,127 patients, of whom 10,707 used cinacalcet before transplant, 551 underwent posttransplant parathyroidectomy, and 5,413 filled≥1 prescription for cinacalcet. The rate of posttransplant parathyroidectomy was stable over time. By contrast, cinacalcet use increased during the period studied. Long dialysis vintage and pretransplant cinacalcet use were strongly associated with posttransplant parathyroidectomy and cinacalcet use. Roughly 1 in 4 patients were hospitalized within 90 days of posttransplant parathyroidectomy, with hypocalcemia-related diagnoses being the most common complication. Parathyroidectomy (vs cinacalcet initiation) was not associated with an increase in acute kidney injury.

LIMITATIONS

We lacked access to laboratory data to help assess the severity of secondary/tertiary hyperparathyroidism. The cohort was limited to Medicare beneficiaries.

CONCLUSIONS

Almost one-fifth of our study cohort was treated with parathyroidectomy and/or cinacalcet. Further studies are needed to establish the optimal treatment for posttransplant hyperparathyroidism.

Maximizing opportunities for kidney transplantation in older adults

PURPOSE OF REVIEW

To summarize the current state of evidence related to the outcomes of older adults who need and receive kidney transplants, and strategies to facilitate appropriate transplant access in this at-risk group.

RECENT FINDINGS

Older adults are a rapidly growing subgroup of the kidney transplant waitlist. Compared to younger adults, older kidney transplant recipients have increased mortality after kidney transplant and lower death-censored graft survival. In determining suitability for transplantation in older patients, clinicians must balance procedural and immunosuppression-related risk with incremental survival when compared with dialysis. To appropriately increase access to transplantation in this population, clinicians and policy makers consider candidates' chronological age and frailty, as well as the quality of and waiting time for a donated allograft. Given risk of deterioration prior to transplant, candidates should be rapidly evaluated, listed, and transplanted using living donor and or less than ideal deceased donor organs when available.

SUMMARY

Access to transplantation for older adults can be increased through targeted interventions to address frailty and reduce waiting times through optimized organ use. Focused study and educational interventions for patients and providers are needed to improve the outcomes of this vulnerable group.

Endovascular creation of hemodialysis arteriovenous fistulae: the current status and future perspective-a literature review

Background and Objective

End-stage renal disease (ESRD) is increasingly prevalent among Americans. Traditionally, the gold standard of dialysis fistulae creation is surgical arteriovenous fistulae (AVF), which is preferred over central venous catheter (CVC) and arteriovenous graft (AVG). However, it is associated with many challenges, particularly its high primary failure rate, which is partially attributed to neointimal hyperplasia. Endovascular creation of arteriovenous fistulae (endoAVF) is a recently emerging method, and is thought to circumvent many of the surgical challenges. It is theorized to reduce the peri-operative trauma to the vessel, thus reducing the amount of neointimal hyperplasia. In this article, we aim to review the current status and future perspectives of endoAVF.

Methods

An electronic search was performed on MEDLINE and Embase to identify relevant articles from 2015 to 2021.

Key Content and Findings

The initial trial data has been promising, resulting in the increased adoption of endoAVF devices in clinical practice. Further, short- and mid-term data has shown that endoAVF has been associated with good maturation rate, re-intervention rate, primary and secondary patency rates. In comparison to historical surgical data, endoAVF has been shown to be comparable in certain aspects. Lastly, endoAVF has been used in an increasing range of clinical applications, including wrist AVF and two-stage transposition procedure.

Conclusions

Although current data has been promising, endoAVF is associated with a host of unique challenges, and the current data has mostly been derived from selective patient population. Further studies are required to further assess its usefulness and its role in the dialysis care algorithm.

Management of concomitant central venous disease

Symptomatic central venous disease (CVD) is a significant common problem in patients with end-stage renal disease given its adverse impact on hemodialysis (HD) vascular access (VA). The current mainstay management is percutaneous transluminal angioplasty (PTA) with or without stenting which is typically reserved for unsatisfactory angioplasty or more challenging lesions. Despite factors such as target vein diameters and lengths and vessel tortuosity that may determine the choice of bare-metal versus covered stents (CS), current scientific literature is pointing out the superiority of the latter one. Alternative management options such as hemodialysis reliable outflow (HeRO) graft showed favorable results in terms of high patency rates and fewer infections, however, complications such as a steal syndrome and, to a lesser extent, graft migration and separation are major concerns. The surgical reconstruction approaches such as bypass, patch venoplasty, or chest wall arteriovenous graft with or without endovascular interventions as a hybrid procedure are still viable options and may be considered. However, further long-term investigations are needed to highlight the comparative outcomes of these approaches. Open surgery might be an alternative before proceeding to more unfavorable approaches such as lower extremity vascular access (LEVA). The appropriate therapy should be selected based upon a patient-centered interdisciplinary discussion utilizing the locally available expertise in the area of VA creation and maintenance.

Sarcopenia of kidney transplant recipients as a predictive marker for reduced graft function and graft survival after kidney transplantation

PURPOSE

The association between sarcopenia of kidney transplant recipients and outcome after kidney transplantation (KT) has not yet been fully understood and is still considered controversial. The aim of our study was to analyze the impact of pre-transplant sarcopenia on graft function, postoperative complication rates, and survival of the patients after renal transplantation.

METHODS

In this retrospective single-center study, all patients who underwent KT (01/2013-12/2017) were included. Demographic data, rejection rates, delayed graft function, and graft and patient survival rates were analyzed. Sarcopenia was measured in computed tomography images by the sex-adjusted Hounsfield unit average calculation (HUAC).

RESULTS

During the study period, 111 single KTs (38 women and 73 men) were performed. Living donor kidney transplants were performed in 48.6%. In total, 32.4% patients had sarcopenia. Sarcopenic patients were significantly older (59.6 years vs. 49.8 years; p < 0.001), had a higher body mass index (BMI = 27.6 kg/m2 vs. 25.0 kg/m2; p = 0.002), and were more likely to receive deceased donor kidneys (72.2% vs. 41.3%; p = 0.002). Interestingly, 3 years after KT, the creatinine serum levels were significantly higher (2.0 mg/dl vs. 1.5 mg/dl; p = 0.001), whereas eGFR (39.9 ml/min vs. 53.4 ml/min; p = 0.001) and graft survival were significantly lower (p = 0.004) in sarcopenic transplant recipients. Sarcopenic patients stayed in hospital significantly longer postoperatively than those who were non-sarcopenic.

CONCLUSIONS

At the time of kidney transplantation, sarcopenia was found to predict reduced long-term graft function and diminished graft survival after KT. The early identification of sarcopenic patients can not only enable an optimized selection of recipients, but also the initiation of pre-habilitation programs during the waiting period.

Distinct phenotypes of kidney transplant recipients aged 80 years or older in the USA by machine learning consensus clustering

OBJECTIVES

This study aimed to identify distinct clusters of very elderly kidney transplant recipients aged ≥80 and assess clinical outcomes among these unique clusters.

DESIGN

Cohort study with machine learning (ML) consensus clustering approach.

SETTING AND PARTICIPANTS

All very elderly (age ≥80 at time of transplant) kidney transplant recipients in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database database from 2010 to 2019.

MAIN OUTCOME MEASURES

Distinct clusters of very elderly kidney transplant recipients and their post-transplant outcomes including death-censored graft failure, overall mortality and acute allograft rejection among the assigned clusters.

RESULTS

Consensus cluster analysis was performed in 419 very elderly kidney transplant and identified three distinct clusters that best represented the clinical characteristics of very elderly kidney transplant recipients. Recipients in cluster 1 received standard Kidney Donor Profile Index (KDPI) non-extended criteria donor (ECD) kidneys from deceased donors. Recipients in cluster 2 received kidneys from older, hypertensive ECD deceased donors with a KDPI score ≥85%. Kidneys for cluster 2 patients had longer cold ischaemia time and the highest use of machine perfusion. Recipients in clusters 1 and 2 were more likely to be on dialysis at the time of transplant (88.3%, 89.4%). Recipients in cluster 3 were more likely to be preemptive (39%) or had a dialysis duration less than 1 year (24%). These recipients received living donor kidney transplants. Cluster 3 had the most favourable post-transplant outcomes. Compared with cluster 3, cluster 1 had comparable survival but higher death-censored graft failure, while cluster 2 had lower patient survival, higher death-censored graft failure and more acute rejection.

CONCLUSIONS

Our study used an unsupervised ML approach to cluster very elderly kidney transplant recipients into three clinically unique clusters with distinct post-transplant outcomes. These findings from an ML clustering approach provide additional understanding towards individualised medicine and opportunities to improve care for very elderly kidney transplant recipients.

De novo major cardiovascular events in kidney transplant recipients: a comparative matched cohort study

BACKGROUND

Although cardiovascular disease is known to be one of the leading causes of death after kidney transplantation (KT), evidence on the risk difference of de novo major adverse cardiovascular events (MACEs) in kidney transplant recipients (KTRs) compared with that in dialysis patients or the general population (GP) remains rare.

METHODS

We identified KTRs using the nationwide health insurance database in South Korea and then 1:1 matched them with the dialysis and GP controls without a pre-existing MACE. The primary endpoint was defined as de novo MACEs consisting of myocardial infarction, coronary revascularization and ischemic stroke. The secondary endpoints were all-cause mortality and death-censored graft failure (DCGF) in KTRs.

RESULTS

We included 4156 individuals in each of the three groups and followed them up for 4.7 years. De novo MACEs occurred in 3.7, 21.7 and 2.5 individuals per 1000 person-years in the KTRs, dialysis controls and GP controls, respectively. KTRs showed a lower MACE risk {adjusted hazard ratio (aHR) 0.16 [95% confidence interval (CI) 0.12-0.20], P < .001} than dialysis controls, whereas a similar MACE risk to GP controls [aHR 0.81 (95% CI 0.52-1.27), P = .365]. In addition, KTRs showed a similar MACE risk compared with the GP group, regardless of age, sex and the presence of comorbidities, including hypertension, diabetes and dyslipidemia. Among KTRs, de novo MACEs were associated with an increased risk of all-cause mortality, but not with DCGF.

CONCLUSIONS

De novo MACEs in KTRs were much lower than that in dialysis patients and had a similar risk to the GP, but once it occurred it caused elevated mortality risk in KTRs.

Association of intraabdominal fat with the risk of incident chronic kidney disease according to body mass index among Korean adults

BACKGROUND

The association between abdominal visceral adipose tissue and the risk of incident chronic kidney disease according to body mass index in the Asian population, remains unclear. We evaluated the impact of abdominal adiposity stratified by body mass index on the risk of incident chronic kidney disease.

METHODS

A cohort study included 11,050 adult participants who underwent health check-ups and re-evaluated the follow-up medical examination at a single university-affiliated healthcare center. Cross-sectional abdominal adipose tissue areas were measured using computed tomography. The primary outcome was progression to chronic kidney disease (estimated glomerular filtration rate <60 ml/min/1.73m2). The highest quartile of visceral adipose tissue was used for the cut-off of central obesity.

RESULTS

During the mean of 5.6 follow-up years, 104 incident chronic kidney disease cases were identified. The risk for chronic kidney disease incidence was significantly increased in the 3rd and 4th quartile ranges of visceral adipose tissue [hazard ratio (95% confidence interval)]: 4.59 (1.48-14.30) and 7.50 (2.33-24.20), respectively. In the analysis stratified by body mass index, the chronic kidney disease incidence risk was increased in the highest quartile range of visceral adipose tissue in the normal weight group: 7.06 (1.35-37.04). However, there was no significant relationship between visceral adipose tissue and chronic kidney disease in the obese group. Compared to the subjects with normal weight and absent central obesity, the hazard ratio for chronic kidney disease incidence was 2.32 (1.26-4.27) among subjects with normal weight and central obesity and 1.81 (1.03-3.15) among subjects with obesity and central obesity.

CONCLUSION

Visceral adipose tissue was a significant risk factor for subsequent chronic kidney disease progression, and the association was identified only in the normal weight group. Normal-weight central obesity was associated with excess risk of chronic kidney disease, similar to the risk in the group with obesity and central obesity.

Effect of kidney transplantation on indices of cardiorespiratory fitness assessed with cardiopulmonary exercise testing: a systematic review and meta-analysis

BACKGROUND

Patients with kidney failure often present with reduced cardiovascular reserve. Kidney transplantation (KT) is the optimal treatment for patients with end-stage kidney disease as it is associated with longer survival and improved quality of life compared to dialysis.

METHODS

This is a systematic review and meta-analysis of studies using cardiopulmonary-exercise-testing to examine the cardiorespiratory fitness of patients with kidney failure before and after KT. The primary outcome was difference in pre- and post-transplantation values of peak oxygen uptake (VO2peak). Literature search involved three databases (PubMed-Web of Science-Scopus), manual search, and grey literature.

RESULTS

From 379 records initially retrieved, six studies were included in final meta-analysis. A marginal, but not significant, improvement was observed in VO2peak after KT compared to pre-transplantation values (SMD: 0.32, 95%CI -0.02; 0.67). Oxygen consumption at anaerobic threshold was significantly improved after KT (WMD: 2.30 ml/kg/min, 95%CI 0.50; 4.09). Consistent results were shown between preemptive and after-dialysis-initiation transplantation and a trend for improvement in VO2peak was observed at least 3 months post-transplantation, but not earlier.

CONCLUSION

Several major indices of cardiorespiratory fitness tend to improve after KT. This finding may represent another modifiable factor contributing to better survival rates of kidney transplant recipients compared to patients undergoing dialysis.

Diagnosis, prevalence, and outcomes of sarcopenia in kidney transplantation recipients: A systematic review and meta-analysis

The prevalence of sarcopenia and its clinical predictors and clinical impact vary among kidney transplant recipients (KTRs), in part because of different diagnostic criteria. This study aimed to assess the reported diagnosis criteria of sarcopenia and compare them in terms of prevalence, clinical predictors, and impact of sarcopenia. The Medline, Embase, and Cochrane Library were searched for the full-length reports published until 28 January 2022. The subgroup analysis, meta-regression, and sensitivity analysis were performed and heterogeneity was assessed using the I² . A total of 681 studies were retrieved, among which only 23 studies (including 2535 subjects, 59.7% men, mean age 49.8 years) were eventually included in the final analysis. The pooled prevalence in these included studies was 26% [95% confidence interval (95% CI): 20-34%, I²  = 93.45%], including 22% (95% CI: 14-32%, I²  = 88.76%) in men and 27% (95% CI: 14-41%, I²  = 90.56%) in women (P = 0.554 between subgroups). The prevalence of sarcopenia diagnosed using low muscle mass was 34% (95% CI: 21-48%, I²  = 95.28%), and the prevalence of using low muscle mass in combination with low muscle strength and/or low physical performance was 21% (95% CI: 15-28%, I²  = 90.37%) (P = 0.08 between subgroups). In meta-regression analyses, the mean age (regression coefficient: 1.001, 95% CI: 0.991-1.011) and percentage male (regression coefficient: 0.846, 95% CI: 0.367-1.950) could not predict the effect size. Lower body mass index (odds ratio (OR): 0.57, 95% CI: 0.39-0.84, I²  = 61.5%), female sex (OR: 0.31, 95% CI: 0.16-0.61, I²  = 0.0%), and higher age (OR: 1.08, 95% CI: 1.05-1.10, I²  = 10.1%) were significantly associated with a higher risk for sarcopenia in KTRs, but phase angle (OR: 0.81, 95% CI: 0.16-4.26, I²  = 84.5%) was not associated with sarcopenia in KTRs. Sarcopenia was not associated with rejections (risk ratio (RR): 0.67, 95% CI: 0.23-1.92, I²  = 12.1%), infections (RR: 1.03, 95% CI: 0.34-3.12, I²  = 87.4%), delayed graft functions (RR: 0.81, 95% CI: 0.46-1.43, I²  = 0.0%), and death (RR: 0.95, 95% CI: 0.32-2.82, I²  = 0.0%) in KRTs. Sarcopenia was found to be very common in KRTs. However, we have not found that sarcopenia had a negative impact on clinical health after kidney transplantation. Large study cohorts and multicentre longitudinal studies in the future are urgently needed to explore the prevalence and prognosis of sarcopenia in kidney transplant patients.

Cannabis Use and Risk of Acute Kidney Injury in Patients with Advanced Chronic Kidney Disease Transitioning to Dialysis

Background: The current social and legal landscape is likely to foster the medicinal and recreational use of cannabis. Synthetic cannabinoid use is associated with acute kidney injury (AKI) in case reports; however, the association between natural cannabis use and AKI risk in patients with advanced chronic kidney disease (CKD) is unknown. Materials and Methods: From a nationally representative cohort of 102,477 U.S. veterans transitioning to dialysis between 2007 and 2015, we identified 2215 patients with advanced CKD who had undergone urine toxicology (UTOX) tests within a year before dialysis initiation and had inpatient serial serum creatinine levels measured within 7 days after their UTOX test. The exposure of interest was cannabis use compared with no use as ascertained by the UTOX test. We examined the association of this exposure with AKI using logistic regression and inverse probability of treatment weighting with extensive adjustment for potential confounders. Results: The mean age of the overall cohort was 61 years; 97% were males, 51% were African Americans, 97% had hypertension, 76% had hyperlipidemia, and 75% were diabetic. AKI occurred in 56% of the cohort, and in multivariable-adjusted analysis, cannabis use (when compared with no substance use) was not associated with significantly higher odds of AKI (odds ratio 0.85, 95% confidence interval 0.38-1.87; p=0.7). These results were robust to various sensitivity analyses. Conclusions: In this observational study examining patients with advanced CKD, cannabis use was not associated with AKI risk. Additional studies are needed to characterize the impact of cannabis use on risk of kidney disease and injury.

All-Cause Standardized Mortality Ratio in Hemodialysis and Peritoneal Dialysis Patients: A Nationwide Population-Based Cohort Study

Patients with end-stage renal disease (ESRD) are at a higher mortality risk compared with the general population. Previous studies have described a relationship between mortality and patients with ESRD, but the data on standardized mortality ratio (SMR) corresponding to different causes of death in patients undergoing hemodialysis (HD) and peritoneal dialysis (PD) are limited. This study was designed as a nationwide population-based retrospective cohort study. Incident dialysis patients between January 2000 and December 2015 in Taiwan were included. Using data acquired from the Taiwan Death Registry, SMR values were calculated and compared with the overall survival. The results showed there were a total of 128,966 patients enrolled, including 117,376 incident HD patients and 11,590 incident PD patients. It was found that 75,297 patients (58.4%) died during the period of 2000-2017. The overall SMR was 5.21. The neoplasms SMR was 2.11; the endocrine, nutritional, metabolic, and immunity disorders SMR was 13.53; the circulatory system SMR was 4.31; the respiratory system SMR was 2.59; the digestive system SMR was 6.1; and the genitourinary system SMR was 27.22. Therefore, more attention should be paid to these diseases in clinical care.

One-Year Mortality after Hemodialysis Initiation: The Prognostic Role of the CHA2DS2-VASc Score

BACKGROUND

CKD is a significant cause of morbidity, cardiovascular and all-cause mortality. CHA2DS2-VASc is a score used in patients with atrial fibrillation to predict thromboembolic risk; it also appears to be useful to predict mortality risk. The aim of the study was to evaluate CHA2DS2-VASc scores as a tool for predicting one-year mortality after hemodialysis is started and for identifying factors associated with higher mortality.

METHODS

Retrospective analysis of patients who started hemodialysis between January 2014 and December 2019 in Centro Hospitalar Universitário Lisboa Norte. We evaluated mortality within one year of hemodialysis initiation. The CHA2DS2-VASc score was calculated at the start of hemodialysis.

RESULTS

Of 856 patients analyzed, their mean age was 68.3 ± 15.5 years and the majority were male (61.1%) and Caucasian (84.5%). Mortality within one-year after starting hemodialysis was 17.8% (n = 152). The CHA2DS2-VASc score was significantly higher (4.4 ± 1.7 vs. 3.5 ± 1.8, p < 0.001) in patients who died and satisfactorily predicted the one-year risk of mortality (AUC 0.646, 95% CI 0.6-0.7, p < 0.001), with a sensitivity of 71.7%, a specificity of 49.1%, a positive predictive value of 23.9% and a negative predictive value of 89.2%. In the multivariate analysis, CHA2DS2-VASc ≥3.5 (adjusted HR 2.24 95% CI (1.48-3.37), p < 0.001) and central venous catheter at dialysis initiation (adjusted HR 3.06 95% CI (1.93-4.85)) were significant predictors of one-year mortality.

CONCLUSION

A CHA2DS2-VASc score ≥3.5 and central venous catheter at hemodialysis initiation were predictors of one-year mortality, allowing for risk stratification in hemodialysis patients.

Genetically proxied therapeutic prolyl-hydroxylase inhibition and cardiovascular risk

Prolyl hydroxylase (PHD) inhibitors are in clinical development for anaemia in chronic kidney disease. Epidemiological studies have reported conflicting results regarding safety of long-term therapeutic haemoglobin (Hgb) rises through PHD inhibition on risk of cardiovascular disease. Genetic variation in genes encoding PHDs can be used as partial proxies to investigate the potential effects of long-term Hgb rises. We used Mendelian randomization to investigate the effect of long-term Hgb level rises through genetically proxied PHD inhibition on coronary artery disease (CAD: 60 801 cases; 123 504 controls), myocardial infarction (MI: 42 561 cases; 123 504 controls) or stroke (40 585 cases; 406 111 controls). To further characterize long-term effects of Hgb level rises, we performed a phenome-wide association study (PheWAS) in up to 451 099 UK Biobank individuals. Genetically proxied therapeutic PHD inhibition, equivalent to a 1.00 g/dl increase in Hgb levels, was not associated (at P < 0.05) with increased odds of CAD; odd ratio (OR) [95% confidence intervals (CI)] = 1.06 (0.84, 1.35), MI [OR (95% CI) = 1.02 (0.79, 1.33)] or stroke [OR (95% CI) = 0.91 (0.66, 1.24)]. PheWAS revealed associations with blood related phenotypes consistent with EGLN's role, relevant kidney- and liver-related biomarkers like estimated glomerular filtration rate and microalbuminuria, and non-alcoholic fatty liver disease (Bonferroni-adjusted P < 5.42E-05) but these were not clinically meaningful. These findings suggest that long-term alterations in Hgb through PHD inhibition are unlikely to substantially increase cardiovascular disease risk; using large disease genome-wide association study data, we could exclude ORs of 1.35 for cardiovascular risk with a 1.00 g/dl increase in Hgb.

Association between Fiber Intake and Risk of Incident Chronic Kidney Disease: The UK Biobank Study

OBJECTIVES

Dietary fiber intake is associated with a lower risk of diabetes, cardiovascular disease, and cancer. However, it is unknown whether dietary fiber has a beneficial effect on preventing the development of chronic kidney disease (CKD).

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Using the UK Biobank prospective cohort, 110,412 participants who completed at least one dietary questionnaire and had an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, urinary albumin-to-creatinine ratio <30 mg/g, and no history of CKD were included. The primary exposure was total dietary fiber density, calculated by dividing the absolute amount of daily total fiber intake by total energy intake (g/1,000 kcal). We separately examined soluble and insoluble fiber densities as additional predictors. The primary outcome was incident CKD based on diagnosis codes.

RESULTS

A total of 3,507 (3.2%) participants developed incident CKD during a median follow-up of 9.9 years. In a multivariable cause-specific model, the adjusted hazard ratios (aHRs; 95% confidence intervals [CIs]) for incident CKD were 0.85 (0.77-0.94), 0.78 (0.70-0.86), and 0.76 (0.68-0.86), respectively, for the second, third, and highest quartiles of dietary fiber density (reference: lowest quartile). In a continuous model, the aHR for each +∆1.0g/1,000 kcal increase in dietary fiber density was 0.97 (95% CI, 0.95-0.99). This pattern of associations was similar for both soluble and insoluble fiber densities and did not differ across subgroups of sex, age, body mass index, hypertension, diabetes, smoking, and inflammation.

CONCLUSION

Increased fiber intake was associated with a lower risk of CKD in this large well-characterized cohort.

Outcomes of kidney transplant recipients who underwent pre-transplant bariatric surgery for severe obesity: a long-term follow-up study

BACKGROUND

Kidney transplantation (KT) is the preferred therapy for end-stage renal disease (ESRD). While a major cause for ESRD, obesity is also a key obstacle to candidacy for KT. Bariatric surgery, particularly sleeve gastrectomy (SG), is increasingly used to improve access to KT in patients with obesity, but the literature especially on outcomes post-KT remains lacking. We aimed to provide a long-term follow-up analysis of efficacy and outcomes of a previously described cohort of patients with obesity, who had SG as a means for access to KT.

METHODS

This is a single-center retrospective follow-up study of 32 patients with advanced chronic kidney disease or ESRD, who were referred and underwent SG between 2013 and 2018 as an access strategy to KT. The primary outcome was successful KT. Ninety-day outcomes, long-term graft function, and changes in weight and obesity-related comorbidities after KT were assessed. Descriptive statistics are presented as count (percentage) or median (interquartile range).

RESULTS

At baseline, 18 (56%) were male with a median age and BMI of 51 (11) years and 42.3 (5.2) kg/m², respectively. Median follow-up time post-SG was 53 (58) months. At last follow-up, 23 (72%) patients received KT. Median time to KT was 16 (20) months and BMI was 34.0 (5.1) kg/m² at time of transplant. At KT, 13 (57%) and 20 (87%) had diabetes and hypertension, respectively. Median follow-up post-KT was 16 (47) months. There was one graft loss requiring return to dialysis. At 5-year post-KT, median serum creatinine was 136 (66) µmol/l. At last follow-up post-KT, median BMI remained at 33.7 (7.6) kg/m². Among patients with diabetes and hypertension, 7/13 (54%) and 5/20 (25%) had either improvement or remission of their comorbidities, respectively.

CONCLUSION

SG is an effective strategy to improve access to KT in patients with severe obesity. Transplant recipients also continue to benefit from sustained weight loss and improved related comorbidities that may positively impact their graft function after KT.

Association between Circulating Ectodysplasin A and Diabetic Kidney Disease

Background

Ectodysplasin A (EDA), a member of the TNF family, plays important roles in ectodermal development, while recent studies expanded its regulatory effects on insulin resistance and lipid metabolism. This study was the first time to investigate the correlation between circulating EDA and albuminuria in patients with T2DM.

Methods

A total of 189 T2DM and 59 healthy subjects were enrolled in the study. We analyzed the concentrations of EDA by ELISA. Plasma glucose, insulin, HbA1c, lipids, creatinine, BUN, and UACR were also measured. Insulin resistance and pancreatic cell function were assessed by HOMA.

Results

Circulating EDA concentration was significantly increased in T2DM patients and increased with the degree of albuminuria. EDA was positively correlated with age, FIns, HOMA-IR, HOMA-β, Scr, and UACR, and negatively correlated with eGFR. Linear stepwise regression showed that FIns, HOMA-β, and UACR were independent influencing factors of EDA. Logistic regression analysis showed that EDA was independently associated with the occurrence of albuminuria in T2DM. ROC curve showed that EDA had an area under the receiver operating curve of 0.701 [95%CI = (0.625 - 0.777), P < 0.001].

Conclusion

EDA is positively correlated with the degree of albuminuria in patients with T2DM and may be involved in the occurrence and progression of diabetic kidney disease (DKD).

Proximal aortic repair in dialysis patients: A national database analysis

OBJECTIVES

Dialysis is a well-established risk factor for morbidity and mortality after cardiovascular procedures. However, little is known regarding the outcomes of proximal aortic surgery in this high-risk cohort.

METHODS

Perioperative (in-hospital or 30-day mortality) and 10-year outcomes were analyzed for all the patients who underwent open proximal aortic repair with the diagnosis of nonruptured thoracic aortic aneurysm (aneurysm, n = 325) or type A aortic dissection (dissection, n = 461) from 1987 to 2015 using the US Renal Data System database.

RESULTS

In patients with aneurysm, perioperative mortality was 12.6%. The 10-year mortality was 81% ± 3%. Age 65 years or more (hazard ratio [HR], 1.35; 95% confidence interval [CI], 1.03 to 1.78; P = .03), chronic obstructive pulmonary disease (HR, 1.68; 95% CI, 1.01-2.82; P = .047), and Black race (HR, 1.46; 95% CI, 1.09-1.97; P = .01) were independently associated with worse 10-year mortality. In patients with dissection, perioperative mortality was 24.3% and 10-year mortality was 87.9% ± 2.2%. Age 65 years or more (HR, 1.49; 95% CI, 1.19-1.86; P < .001), congestive heart failure (HR, 1.39; 95% CI, 1.11-2.57; P = .004), and diabetes mellitus as the cause of dialysis (HR, 1.75; 95% CI, 1.2-2.57; P = .004) were independently associated with worse 10-year mortality. Black race (HR, 0.74; 95% CI, 0.6-0.92; P = .008) was associated with a better outcome.

CONCLUSIONS

We described challenging perioperative and 10-year outcomes for dialysis patients undergoing proximal aortic repair. The present study suggests the need for careful patient selection in the elective repair of proximal aortic aneurysm for dialysis-dependent patients, whereas it affirms the feasibility of emergency surgery for acute type A aortic dissections.

Physical performance and muscle strength rather than muscle mass are predictor of all-cause mortality in hemodialysis patients

Objectives

Patients undergoing maintenance hemodialysis usually suffer a high burden of poor functional status. The aim of this study was to investigate the association between muscle mass, muscle strength as well as physical performance with all-cause mortality in hemodialysis patients.

Methods

923 hemodialysis patients (565 men, mean aged 61.3 ± 12.7 years) were included from eight facilities in Tianjin and Shanghai of China from 2019 to 2021. Muscle mass was evaluated by skeletal muscle index (SMI) and muscle strength was assessed by handgrip strength. Different measures of physical performance were measured via gait speed, Timed Up and Go Test (TUGT) and short physical performance battery (SPPB). Cox proportional hazards regression models were used to determine the adjusted hazard ratios (HRs) of mortality with 95% confidence intervals (95% CIs) for baseline muscle mass, muscle strength and different measures of physical performance. Additionally, the area under the Receiver Operating Characteristic (ROC) curves were constructed to determine which index is a better predictor of mortality.

Results

During a median follow-up of 14 (12-17 months), 79 (8.6%) patients died. Using the Cox regression analysis, we founded that muscle strength and physical performance rather than muscle mass were significantly negatively associated with mortality. The C-index for different measures of physical performance in predicting mortality were 0.709 for SPPB, 0.7 for TUGT and 0.678 for gait speed, respectively. The C-index for muscle strength was 0.635, and the ability of prediction was significantly lower than the physical performance.

Conclusions

Physical performance seems to a better indicator of mortality than muscle mass and strength in hemodialysis patients. Simple measures of physical performance may be appropriately used as a screening tool targeting high-risk hemodialysis patients for the prevention of mortality.

The effects of mineralocorticoid receptor antagonists on cardiovascular outcomes in patients with end-stage renal disease and heart failure

AIMS

Mineralocorticoid receptor antagonists (MRAs) have been shown to provide survival benefits in patients with heart failure; however, MRA use in patients with chronic kidney disease has been limited by safety concerns. The effects of MRAs on outcomes in patients with end-stage renal disease (ESRD) and heart failure remain unknown. The aim of this study was to evaluate the effects of MRAs on cardiovascular outcomes in patients with heart failure under maintenance dialysis in a real-world setting.

METHODS AND RESULTS

A retrospective cohort study was conducted by collecting data from the Taiwan National Health Insurance Research Database (NHIRD). Patients diagnosed with heart failure and ESRD and who started maintenance dialysis between 1 January 2001 and 31 December 2013 were identified. Patients were grouped according to MRA prescription. The outcomes of interest included cardiovascular (CV) death, hospitalization for heart failure (HHF), all-cause mortality, acute myocardial infarction (AMI), ischaemic stroke, any coronary revascularization procedures, and new-onset hyperkalaemia. Propensity score matching was performed at a 1:3 ratio between MRA users and non-users to minimize selection bias. A total of 50 872 patients who satisfied our inclusion and exclusion criteria were identified. After 1:3 matching, 2176 patients were included in the MRA group, and 6528 patients were included in the non-MRA group. The risk of CV death was significantly lower among patients who received MRAs than those who did not (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.80-0.95), as was the risk of all-cause mortality (HR 0.88, 95% CI 0.83-0.94). Reductions in the risks of CV death and all-cause mortality were more prominent among patients undergoing haemodialysis and those with coronary artery disease.

CONCLUSIONS

In patients undergoing regular dialysis who are diagnosed with heart failure, the use of MRAs is associated with lower risks of all-cause mortality and CV death. The benefits of MRA treatment in heart failure may persist in patients with ESRD. Further investigations through randomized controlled trials are needed to assess the efficacy and safety of MRAs in this high-risk population.

Increased soluble urokinase plasminogen activator levels modulate monocyte function to promote atherosclerosis

People with kidney disease are disproportionately affected by atherosclerosis for unclear reasons. Soluble urokinase plasminogen activator receptor (suPAR) is an immune-derived mediator of kidney disease, levels of which are strongly associated with cardiovascular outcomes. We assessed suPAR's pathogenic involvement in atherosclerosis using epidemiologic, genetic, and experimental approaches. We found serum suPAR levels to be predictive of coronary artery calcification and cardiovascular events in 5,406 participants without known coronary disease. In a genome-wide association meta-analysis including over 25,000 individuals, we identified a missense variant in the plasminogen activator, urokinase receptor (PLAUR) gene (rs4760), confirmed experimentally to lead to higher suPAR levels. Mendelian randomization analysis in the UK Biobank using rs4760 indicated a causal association between genetically predicted suPAR levels and atherosclerotic phenotypes. In an experimental model of atherosclerosis, proprotein convertase subtilisin/kexin-9 (Pcsk9) transfection in mice overexpressing suPAR (suPARTg) led to substantially increased atherosclerotic plaques with necrotic cores and macrophage infiltration compared with those in WT mice, despite similar cholesterol levels. Prior to induction of atherosclerosis, aortas of suPARTg mice excreted higher levels of CCL2 and had higher monocyte counts compared with WT aortas. Aortic and circulating suPARTg monocytes exhibited a proinflammatory profile and enhanced chemotaxis. These findings characterize suPAR as a pathogenic factor for atherosclerosis acting at least partially through modulation of monocyte function.

Calorie Restriction Provides Kidney Ischemic Tolerance in Senescence-Accelerated OXYS Rats

Kidney diseases belong to a group of pathologies, which are most common among elderly people. With age, even outwardly healthy organisms start to exhibit some age-related changes in the renal tissue, which reduce the filtration function of kidneys and increase the susceptibility to injury. The therapy of acute kidney injury (AKI) is aggravated by the absence of targeted pharmacotherapies thus yielding high mortality of patients with AKI. In this study, we analyzed the protective effects of calorie restriction (CR) against ischemic AKI in senescence-accelerated OXYS rats. We observed that CR afforded OXYS rats with significant nephroprotection. To uncover molecular mechanisms of CR beneficial effects, we assessed the levels of anti- and proapoptotic proteins of the Bcl-2 family, COX IV, GAPDH, and mitochondrial deacetylase SIRT-3, as well as alterations in total protein acetylation and carbonylation, mitochondrial dynamics (OPA1, Fis1, Drp1) and kidney regeneration pathways (PCNA, GDF11). The activation of autophagy and mitophagy was analyzed by LC3 II/LC3 I ratio, beclin-1, PINK-1, and total mitochondrial protein ubiquitination. Among all considered protective pathways, the improvement of mitochondrial functioning may be suggested as one of the possible mechanisms for beneficial effects of CR.

PRE-084 ameliorates adenine-induced renal fibrosis in rats

2-(4-morpholinoethyl)- 1-phenylcyclohexane-1-carboxylate hydrochloride (PRE-084) is a selective sigma 1 receptor agonist. It has been shown that PRE-084 protected various tissues from experimental injury. However, no reports are available on its effect on renal fibrosis. Rat model of adenine-induced chronic kidney disease was chosen to study this. Adenine feeding in rats caused renal dysfunction as shown by increased serum creatinine and reduced creatinine clearance along with increased high molecular weight (HMW) urine protein excretion. Further, adenine feeding induced profibrotic changes in the kidney as reflected by increased expression of alpha-smooth muscle actin (α-SMA), fibroblast specific protein-1 (FSP-1) and matrix metalloproteinase-2 (MMP-2) activity; reduced cytokeratin expression. Further, there was excess deposition of extracellular matrix in the kidney, a striking character of fibrosis. However, administration of PRE-084 to adenine fed rats led to reduction in creatinine and proteinuria parameters partly. This was accompanied by reduced expression of α-SMA, FSP-1 and MMP-2 activity and slight restoration of cytokeratin levels leading to reduced extracellular matrix deposition in the kidney. These data demonstrate that PRE-084 partly ameliorated renal dysfunction and exhibited anti-fibrotic potential in the kidney of adenine fed rats.

Left ventricular dysfunction with preserved ejection fraction: the most common left ventricular disorder in chronic kidney disease patients

Chronic kidney disease (CKD) is a risk factor for premature cardiovascular disease. As kidney function declines, the presence of left ventricular abnormalities increases such that by the time kidney replacement therapy is required with dialysis or kidney transplantation, more than two-thirds of patients have left ventricular hypertrophy. Historically, much research in nephrology has focussed on the structural and functional aspects of cardiac disease in CKD, particularly using echocardiography to describe these abnormalities. There is a need to translate knowledge around these imaging findings to clinical outcomes such as unplanned hospital admission with heart failure and premature cardiovascular death. Left ventricular hypertrophy and cardiac fibrosis, which are common in CKD, predispose to the clinical syndrome of heart failure with preserved left ventricular ejection fraction (HFpEF). There is a bidirectional relationship between CKD and HFpEF, whereby CKD is a risk factor for HFpEF and CKD impacts outcomes for patients with HFpEF. There have been major improvements in outcomes for patients with heart failure and reduced left ventricular ejection fraction as a result of several large randomized controlled trials. Finding therapy for HFpEF has been more elusive, although recent data suggest that sodium-glucose cotransporter 2 inhibition offers a novel evidence-based class of therapy that improves outcomes in HFpEF. These observations have emerged as this class of drugs has also become the standard of care for many patients with proteinuric CKD, suggesting that there is now hope for addressing the combination of HFpEF and CKD in parallel. In this review we summarize the epidemiology, pathophysiology, diagnostic strategies and treatment of HFpEF with a focus on patients with CKD.

The neutrophil-to-lymphocyte ratio may indicate when to start hemodialysis

We evaluated whether the neutrophil-to-lymphocyte ratio (NLR) could aid dialysis decision-making in combination with the clinical presentation and biochemical findings. We retrospectively evaluated the medical records of 279 patients who commenced chronic maintenance hemodialysis. We compared the laboratory findings at 6 months before dialysis to those at dialysis initiation. NLR cutoffs and risk factors for each of six uremic symptoms were determined. Mean age was 60.7 years and mean estimated glomerular filtration rate (eGFR) was 5.7 ± 2.5 mL/min/1.73 m² at the time of hemodialysis and 7.7 ± 3.8 mL/min/1.73 m² 6 months earlier (p < 0.001). The mean NLR increased significantly from 2.5 ± 1.0 to 4.9 ± 2.8 (p < 0.001). The NLR was positively correlated with the C-reactive protein level (r = 0.202, p = 0.009) and negatively correlated with those of albumin (r = −0.192, p = 0.001) and total CO₂ (r = −0.134, p = 0.023). The NLR cutoffs for neurological and gastrointestinal symptoms as determined using receiver operator curve analysis were 2.4 (area under the curve [AUC] 0.976; 95% confidence interval [CI] 0.960–0.993; sensitivity 92.2%; specificity 94.7%) and 3.6 (AUC 0.671; 95% CI 0.588–0.755; sensitivity 68.1%; specificity 63.5%), respectively. On multiple linear regression analysis of neurological symptoms, the NLR was a significant predictor (β = −0.218, p = 0.017), as was age (β = 0.314, p = 0.037). In conclusion, the NLR may serve as a supplementary marker predicting uremic symptoms and a need for hemodialysis in stage 5 CKD patients.

The needs of families who care for individuals with kidney failure on comprehensive conservative care: A qualitative systematic review

BACKGROUND

Integrating the family of patients with kidney failure on comprehensive conservative care could benefit patients, families, and the health care system. However, there is a knowledge gap in this phenomenon since no systematic review has focused on the families' needs who care for individuals with kidney failure on comprehensive conservative care.

OBJECTIVES

To understand the primary needs of families who care for people with kidney failure on comprehensive conservative care.

METHOD

A systematic literature review of qualitative studies, followed by a content analysis was carried out. PubMed, CINAHL, and PsycINFO databases were used to search for articles published in English and Spanish between 2010 and 2021. The ENTREQ guideline was used for reporting.

RESULTS

Five relevant studies were included in this study. The analysis has allowed identifying key aspects of knowledge, psychological, social and spiritual needs of family members of patients with kidney failure on comprehensive conservative care.

CONCLUSIONS

This systematic review has revealed that families experience a lack of information and continuity of care by health care professionals. Added to this is the psychological burden they bear due to the feeling of indefinite care in time and uncertainty about the death of their loved one. All this, without the necessary support from their immediate family environment and social institutions. In light of these data, a paradigm shift in society and the health care received by these families is essential.

Chronic Kidney Disease in Children

Chronic kidney disease (CKD) in children occurs mostly due to congenital anomalies of kidney and urinary tract and hereditary diseases. For advanced cases, a multidisciplinary team is needed to manage nutritional requirements and complications such as hypertension, hyperphosphatemia, proteinuria, and anemia. Neurocognitive assessment and psychosocial support are essential. Maintenance dialysis in children with end-stage renal failure has become the standard of care in many parts of the world. Children younger than 12 years have 95% survival after 3 years of dialysis initiation, whereas the survival rate for children aged 4 years or younger is about 82% at one year."

Identification of Serum Metabolites for Predicting Chronic Kidney Disease Progression according to Chronic Kidney Disease Cause

Early detection and proper management of chronic kidney disease (CKD) can delay progression to end-stage kidney disease. We applied metabolomics to discover novel biomarkers to predict the risk of deterioration in patients with different causes of CKD. We enrolled non-dialytic diabetic nephropathy (DMN, n = 124), hypertensive nephropathy (HTN, n = 118), and polycystic kidney disease (PKD, n = 124) patients from the KNOW-CKD cohort. Within each disease subgroup, subjects were categorized as progressors (P) or non-progressors (NP) based on the median eGFR slope. P and NP pairs were randomly selected after matching for age, sex, and baseline eGFR. Targeted metabolomics was performed to quantify 188 metabolites in the baseline serum samples. We selected ten progression-related biomarkers for DMN and nine biomarkers each for HTN and PKD. Clinical parameters showed good ability to predict DMN (AUC 0.734); however, this tendency was not evident for HTN (AUC 0.659) or PKD (AUC 0.560). Models constructed with selected metabolites and clinical parameters had better ability to predict CKD progression than clinical parameters only. When selected metabolites were used in combination with clinical indicators, random forest prediction models for CKD progression were constructed with AUCs of 0.826, 0.872, and 0.834 for DMN, HTN, and PKD, respectively. Select novel metabolites identified in this study can help identify high-risk CKD patients who may benefit from more aggressive medical treatment.

Impact of donor hypertension on graft survival and function in living and deceased donor kidney transplantation: a nationwide prospective cohort study

OBJECTIVES

Hypertensive living donors are potential candidates to expand the kidney donor pool. However, the impact of donor hypertension on graft survival and function remains to be clarified.

METHODS

We analyzed 3907 kidney transplant recipients registered in a nationwide prospective cohort from 2014 to 2018. Patients were divided by donor types and the presence of donor hypertension. The primary and secondary outcome was the occurrence of death-censored graft failure and renal allograft function, respectively.

RESULTS

The prevalence of hypertension was 9.4% (258/2740) and 19.9% (232/1167) in living and deceased donors, respectively. During a median follow-up of 21.8 months, death-censored graft survival rate was significantly worse in recipients of hypertensive living donors than in those of normotensive living donors ( P  = 0.008). In multivariable analysis, recipients of hypertensive living donors had a significantly increased risk of graft loss (adjusted hazard ratio 2.91; P  = 0.009). The risk of allograft loss was not different between recipients of hypertensive living and normotensive deceased donors. Propensity score-matched analyses had consistent worse graft survival rate in recipients of hypertensive living donors compared to those of normotensive living donors ( P  = 0.027), while it was not different between recipients of hypertensive living and normotensive deceased donors. Hypertension in living donors had a significant negative impact on one-year graft function (adjusted unstandardized β -3.64; P  = 0.011).

CONCLUSIONS

Hypertensive living donor recipients have significantly higher risks of renal allograft loss than normotensive living donor recipients, and showed similar outcomes compared to recipients of normotensive deceased donors.

Intradialytic hypertension: epidemiology and pathophysiology of a silent killer

The term intradialytic hypertension (IDH) describes a paradoxical rise in blood pressure (BP) during or immediately after the hemodialysis session. Although it was formerly considered a phenomenon without clinical implications, current evidence suggests that IDH may affect up to 15% of hemodialysis patients and exhibit independent associations with future cardiovascular events and all-cause mortality. Furthermore, during the last decade, several studies have tried to elucidate the complex pathophysiological mechanisms responsible for this phenomenon. Volume overload, intradialytic sodium gain, overactivity of the sympathetic-nervous-system and renin-angiotensin-aldosterone system, endothelial dysfunction and dialysis-related electrolyte disturbances have been proposed to be involved in the pathogenesis of the BP increase during hemodialysis. This review attempts to summarize existing evidence on the epidemiology, pathophysiology and clinical characteristics of the distinct phenomenon of IDH.

Analysis of hospital readmissions with competing risks

The 30-day hospital readmission rate has been used in provider profiling for evaluating inter-provider care coordination, medical cost effectiveness, and patient quality of life. Current profiling analyzes use logistic regression to model 30-day readmission as a binary outcome, but one disadvantage of this approach is that this outcome is strongly affected by competing risks (e.g., death). Thus, one, perhaps unintended, consequence is that if two facilities have the same rates of readmission, the one with the higher rate of competing risks will have the lower 30-day readmission rate. We propose a discrete time competing risk model wherein the cause-specific readmission hazard is used to assess provider-level effects. This approach takes account of the timing of events and focuses on the readmission rates which are of primary interest. The quality measure, then is a standardized readmission ratio, akin to a standardized mortality ratio. This measure is not systematically affected by the rate of competing risks. To facilitate the estimation and inference of a large number of provider effects, we develop an efficient Blockwise Inversion Newton algorithm, and a stabilized robust score test that overcomes the conservative nature of the classical robust score test. An application to dialysis patients demonstrates improved profiling, model fitting, and outlier detection over existing methods.

Black and White Adults With CKD Hospitalized With Acute Kidney Injury: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVE

Few studies have investigated racial disparities in acute kidney injury (AKI), in contrast to the extensive literature on racial differences in the risk of kidney failure. We sought to study potential differences in risk in the setting of chronic kidney disease (CKD).

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

We studied 2,720 self-identified Black or White participants with CKD enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study from July 1, 2013, to December 31, 2017.

EXPOSURE

Self-reported race (Black vs White).

OUTCOME

Hospitalized AKI (≥50% increase from nadir to peak serum creatinine).

ANALYTICAL APPROACH

Cox regression models adjusting for demographics (age and sex), prehospitalization clinical risk factors (diabetes, blood pressure, cardiovascular disease, estimated glomerular filtration rate, proteinuria, receipt of angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers), and socioeconomic status (insurance status and education level). In a subset of participants with genotype data, we adjusted for apolipoprotein L1 gene (APOL1) high-risk status and sickle cell trait.

RESULTS

Black participants (n = 1,266) were younger but had a higher burden of prehospitalization clinical risk factors. The incidence rate of first AKI hospitalization among Black participants was 6.3 (95% CI, 5.5-7.2) per 100 person-years versus 5.3 (95% CI, 4.6-6.1) per 100 person-years among White participants. In an unadjusted Cox regression model, Black participants were at a modestly increased risk of incident AKI (HR, 1.22 [95% CI, 1.01-1.48]) compared with White participants. However, this risk was attenuated and no longer significant after adjusting for prehospitalization clinical risk factors (adjusted HR, 1.02 [95% CI, 0.83-1.25]). There were only 11 AKI hospitalizations among individuals with high-risk APOL1 risk status and 14 AKI hospitalizations among individuals with sickle cell trait.

LIMITATIONS

Participants were limited to research volunteers and potentially not fully representative of all CKD patients.

CONCLUSIONS

In this multicenter prospective cohort of CKD patients, racial disparities in AKI incidence were modest and were explained by differences in prehospitalization clinical risk factors.

Shared Decision Making Among Older Adults With Advanced CKD

RATIONALE & OBJECTIVE

Older adults with advanced chronic kidney disease (CKD) face difficult decisions about dialysis initiation. Although shared decision making (SDM) can help align patient preferences and values with treatment options, the extent to which older patients with CKD experience SDM remains unknown.

STUDY DESIGN

A cross-sectional analysis of patient surveys examining decisional readiness, treatment options education, care partner support, and SDM.

SETTING & PARTICIPANTS

Adults aged 70 years or older from Boston, Chicago, San Diego, or Portland (Maine) with nondialysis advanced CKD.

PREDICTORS

Decisional readiness factors, treatment options education, and care partner support.

OUTCOMES

Primary: SDM measured by the 9-item Shared Decision Making Questionnaire (SDM-Q-9) instrument, with higher scores reflecting greater SDM. Exploratory: Factors associated with SDM.

ANALYTICAL APPROACH

We used multivariable linear regression models to examine the associations between SDM and predictors, controlling for demographic and health factors.

RESULTS

Among 350 participants, mean age was 78 ± 6 years, 58% were male, 13% identified as Black, and 48% had diabetes. Mean SDM-Q-9 score was 52 ± 28. SDM item agreement ranged from 41% of participants agreeing that "my doctor and I selected a treatment option together" to 73% agreeing that "my doctor told me that there are different options for treating my medical condition." In multivariable analysis adjusted for demographic characteristics, lower estimated glomerular filtration rate, and diabetes, being "well informed" and "very well informed" about kidney treatment options, having higher decisional certainty, and attendance at a kidney treatment options class were independently associated with higher SDM-Q-9 scores.

LIMITATIONS

The cross-sectional study design limits the ability to make temporal associations between SDM and the predictors.

CONCLUSIONS

Many older patients with CKD do not experience SDM when making dialysis decisions, emphasizing the need for greater access to and delivery of education for individuals with advanced CKD.

Association of Estimated Glomerular Filtration Rate with Risk of Head and Neck Cancer: A Nationwide Population-Based Study

In this study, through a cohort study of 10 million people, we investigated the association between estimated glomerular filtration rate (eGFR) and head and neck cancer (HNC) incidence. This is an observational cohort study using data from the national health claims database established by the Korean National Health Insurance Service (NHIS). We selected 9,598,085 participants older than 20 years who had undergone health checkups in 2009. A health checkup involves the history of any diseases, current health status, and results of several physical and blood exams including eGFR. We investigated the presence of HNC diagnosis in their national health insurance data from 2010 to 2018. Of the 9,598,085 participants, 10,732 had been newly diagnosed with HNC in the 9-year follow-up. In the multivariate Cox proportional hazard model, participants with elevated eGFR were associated with a risk of HNC incidence (HR = 1.129; 95% CI = 1.075−1.186 for eGFR = 90−104 mL/min/1.73 m2 and HR = 1.129; 95% CI = 1.076−1.194 for eGFR ≥ 105 mL/min/1.73 m2) compared with those with eGFR 60−89 mL/min/1.73 m2. Among HNC, the incidences of oral cavity, oropharyngeal, hypopharyngeal, and laryngeal cancers were significantly increased in the elevated eGFR group. According to the subgroup analysis, participants with eGFR ≥ 60 mL/min/1.73 m2 were correlated with risk of HNC incidence in middle age, non/mild drinker, low BMI, no diabetes, and no hypertension patients compared with those with eGFR < 60 mL/min/1.73 m2. Elevated eGFR was associated with the risk of some type of HNC, even in individuals with adjusted hypertension and diabetes without chronic diseases. The results of this study have implications for etiological investigations and preventive strategies.

GC × GC-TOFMS metabolomics analysis identifies elevated levels of plasma sugars and sugar alcohols in diabetic mellitus patients with kidney failure

Two dimensional GC (GC × GC)-time-of-flight mass spectrometry (TOFMS) has been used to improve accurate metabolite identification in the chemical industry, but this method has not been applied as readily in biomedical research. Here, we evaluated and validated the performance of high resolution GC × GC-TOFMS against that of GC-TOFMS for metabolomics analysis of two different plasma matrices, from healthy controls (CON) and diabetes mellitus (DM) patients with kidney failure (DM with KF). We found GC × GC-TOFMS outperformed traditional GC-TOFMS in terms of separation performance and metabolite coverage. Several metabolites from both the CON and DM with KF matrices, such as carbohydrates and carbohydrate-conjugate metabolites, were exclusively detected using GC × GC-TOFMS. Additionally, we applied this method to characterize significant metabolites in the DM with KF group, with focused analysis of four metabolite groups: sugars, sugar alcohols, amino acids, and free fatty acids. Our plasma metabolomics results revealed 35 significant metabolites (12 unique and 23 concentration-dependent metabolites) in the DM with KF group, as compared with those in the CON and DM groups (N = 20 for each group). Interestingly, we determined 17 of the 35 (14/17 verified with reference standards) significant metabolites identified from both the analyses were metabolites from the sugar and sugar alcohol groups, with significantly higher concentrations in the DM with KF group than in the CON and DM groups. Enrichment analysis of these 14 metabolites also revealed that alterations in galactose metabolism and the polyol pathway are related to DM with KF. Overall, our application of GC × GC-TOFMS identified key metabolites in complex plasma matrices.

Outcomes after Elective Abdominal Aortic Aneurysm Repair Have Improved Over Time in Patients on Dialysis

BACKGROUND

Prior studies have demonstrated poor perioperative and long-term survival of patients with end-stage kidney disease (ESKD) on dialysis who undergo abdominal aortic aneurysm repair (AAAR). However, survival in dialysis patients overall has improved over time. We hypothesize that the contemporary rates of perioperative and long-term survival following AAAR in ESKD patients are also improving.

METHODS

Data on AAAR procedures in dialysis patients were collected from the United States Renal Data System between 2008 and 2017. Endovascular (EVAR) and open AAA repair (OAR) were identified by Current Procedural Terminology codes. Patients with a functioning renal transplant, a ruptured aneurysm, and insurance other than Medicare were excluded. Demographics, comorbidities, procedural details, and long-term outcomes were collected. Standard statistical methods were used.

RESULTS

We identified 3,374 patients who underwent EVAR (86%, 2,914/3,374) and OAR (14%, 460/3,374). The utilization of OAR decreased significantly from 2008 to 2017 (17.34% vs. 7.43%, P < 0.001). Kaplan-Meier survival analysis revealed no significant difference in 5-year survival between OAR and EVAR (24% vs. 17%, P = 0.1, Wilcoxon-Breslow test), but open repair was associated with increased long-term survival (Hazards ratio 0.994, confidence interval 0.990-0.999, P = 0.017) in an adjusted Cox regression model. The cohort was then divided based on the year of AAAR, group 1: 2008-2010 (1,269/3,374), group 2: 2011-2013 (1,071/3,374), and group 3: 2014-2017 (1,034/3,374). Compared to groups 1 and 2, Group 3 was less likely to have coronary artery device, peripheral vascular disease, recent pneumonia, be nonambulatory, live in a nursing facility, or undergo an OAR and more likely to be younger and dialyze through an arteriovenous fistula/arteriovenous graft at the time of AAA repair. Thirty-day postoperative mortality was significantly lower in group 3 compared to groups 1 and 2 (5.4% [56/1,034] vs. 10.3% [131/1,269]/7.3% [78/1,071], P < 0.031). One-year survival by Kaplan-Meier estimate was significantly higher in group 3 (77.7% [803/1,034]) versus groups 1 and 2 (56.7% [719/1,269], 66.9% [716/1,071], P < 0.001, log-rank test). Five-year survival was also significantly higher in group 3 (27.3%) compared to groups 1 and 2 (14.2% and 16.5%, P < 0.001, log-rank test). In a Cox regression model of long-term mortality adjusted for variables significant on a univariate testing, more recent procedure year was associated with increased survival (Hazards ratio 0.81, [0.77, 0.85], P < 0.001).

CONCLUSIONS

Postoperative and long-term survival following AAA repair have increased over time in ESKD patients on dialysis. This increased survival persists after accounting for differences in patient demographics and type of procedure over time. Elective AAA repair should be considered in carefully selected good-risk patients on dialysis.

Bio-inspired hemocompatible surface modifications for biomedical applications

When blood first encounters the artificial surface of a medical device, a complex series of biochemical reactions is triggered, potentially resulting in clinical complications such as embolism/occlusion, inflammation, or device failure. Preventing thrombus formation on the surface of blood-contacting devices is crucial for maintaining device functionality and patient safety. As the number of patients reliant on blood-contacting devices continues to grow, minimizing the risk associated with these devices is vital towards lowering healthcare-associated morbidity and mortality. The current standard clinical practice primarily requires the systemic administration of anticoagulants such as heparin, which can result in serious complications such as post-operative bleeding and heparin-induced thrombocytopenia (HIT). Due to these complications, the administration of antithrombotic agents remains one of the leading causes of clinical drug-related deaths. To reduce the side effects spurred by systemic anticoagulation, researchers have been inspired by the hemocompatibility exhibited by natural phenomena, and thus have begun developing medical-grade surfaces which aim to exhibit total hemocompatibility via biomimicry. This review paper aims to address different bio-inspired surface modifications that increase hemocompatibility, discuss the limitations of each method, and explore the future direction for hemocompatible surface research.