Abdominal lean muscle is associated with lower mortality among kidney waitlist candidates

Morphometric assessments, such as muscle density and body fat distribution, have emerged as strong predictors of cardiovascular risk and postoperative morbidity and mortality. To date, no study has examined morphometric mortality risk prediction among kidney transplant (KT) candidates. KT candidates, waitlisted 2008‐2009, were identified (n=96) and followed to the earliest of transplant, death, or administrative end of study. Morphometric measures, including abdominal adipose tissue, paraspinous and psoas muscle composition, and aortic calcification, were measured from CTs. Risk of waitlist mortality was examined using Cox proportional hazard regression. On adjusted analyses, radiologic measures remained independently and significantly associated with lower waitlist mortality; the addition of radiologic measures significantly improved model predictive ability over models containing traditional risk factors alone (net reclassification index: 0.56, 95% CI: 0.31‐0.75). Higher psoas muscle attenuation (indicative of leaner muscle) was associated with decreased risk of death (aHR: 0.93, 95% CI: 0.91‐0.96, P<.001), and for each unit increase in lean paraspinous volume, there was an associated 2% decreased risk for death (aHR: 0.98, 95% CI: 0.96‐0.99, P=.03). Radiologic measures of lean muscle mass, such as psoas muscle attenuation and paraspinous lean volume, may improve waitlist mortality risk prediction and candidate selection.     

ESRD patients using permanent vascular access report greater physical activity compared with catheter users

Purpose

Low levels of physical activity among end-stage renal disease (ESRD) patients are associated with increased risk of hospitalization and mortality, and contributors to low activity levels are important to identify. Among hemodialysis (HD) patients, use of a central venous catheter (CVC) might impede physical activity due to factors such as infection or patient fear of catheter dislodgement.

Methods

This Comprehensive Dialysis Study surveyed patients who had recently started regular dialysis. Physical activity level was ascertained using responses to the Human Activity Profile (HAP) provided by 1,458 HD participants. We examined the association of vascular access type with patients’ scores on HAP subscales measuring self-care and leg effort, two dimensions that are especially important for daily living.

Results

32.6% of patients used an arteriovenous fistula (AVF), 11.5% used an arteriovenous graft, 51.8% used a CVC, and 4.1% used a CVC with another maturing access. Patients’ self-care and leg effort scores differed by vascular access type and receipt of early nephrology care, and the mean self-care score of AVF users who received early care was similar to the mean score reported for healthy adults.

Conclusions

Reported levels of self-care and leg effort activity were higher among incident HD patients using an AVF compared to those using a CVC. Future research should examine whether reinforcing the importance of regular physical activity in the pre-dialysis period, as well as wider early use of AVF in the HD population, may improve physical activity levels among ESRD patients.     

HMG-CoA reductase inhibitors are associated with reduced mortality in ESRD patients.

BACKGROUND.: Patients with end-stage renal disease (ESRD) suffer from markedly higher rates of cardiovascular disease than the general population. Although therapy with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors ("statins") has been demonstrated to reduce the mortality from cardiovascular disease in patients without ESRD, only 10% of patients on dialysis are treated with these medications by day 60 of ESRD. We determined whether the use of statins is associated with a reduction in cardiovascular-specific death and total mortality in ESRD patients. METHODS: Data were analyzed from the U.S. Renal Data System Dialysis Morbidity and Mortality Wave-2 study, a cohort of randomly selected patients who were initiating dialysis in 1996. Information about the use of statins as well as other baseline characteristics was abstracted from the patients' dialysis records by dialysis personnel. Cox proportional hazards models were developed to determine the association between use of statins at baseline and subsequent risk of mortality, with adjustment for known mortality risk factors. RESULTS: Follow-up data were available for 3716 patients through July 1998. At baseline, 362 (9.7%) of patients were using statins. These patients had a mortality rate of 143/1000 person-years, compared with a rate of 202/1000 person-years for patients not using statins. Statin use was independently associated with a reduced risk of total mortality [relative risk (RR)=0.68, 95% confidence interval (CI)=0.54, 0.87] as well as cardiovascular-specific mortality (RR=0.64, 95% CI=0.45, 0.91). In contrast, the use of fibrates was not associated with reduced mortality (RR=1.29). CONCLUSIONS: Statin use was associated with a reduction in cardiovascular-specific death and total mortality in patients on dialysis.     

Arteriovenous fistula aneurysmorrhaphy is associated with improved patency and decreased vascular access abandonment

BackgroundUpper extremity hemodialysis arteriovenous fistulas (AVFs) can become aneurysmal over time due to repeated cannulation and/or outflow steno-occlusive disease. The optimal surgical management of aneurysmal AVFs (aneurysmorrhaphy vs interposition graft) has remained unclear.MethodsWe performed a retrospective review in which current procedural terminology codes were used to screen for patients who had undergone surgical treatment of aneurysmal AVFs between 2016 and 2021 at a single hospital system. The patients were included after a review of the operative reports. The cases were divided by surgical procedure (aneurysmorrhaphy vs interposition graft placement). The patients who had undergone primary AVF ligation or other types of repair were excluded. The primary outcomes were primary assisted and secondary patency, and the secondary outcome was dialysis access abandonment. Multivariable Cox proportional hazards regression was used to test the association between the type of AVF aneurysm repair and the primary and secondary outcomes.ResultsFrom 2016 to 2021, 6951 patients had undergone 16,190 dialysis access procedures. Of these procedures, 381 (2.4%) were related to surgical treatment of an aneurysmal AVF. We excluded 58 primary AVF ligation cases and 20 cases involving other types of repair, leaving 303 cases for analysis. These were divided into two groups: aneurysmorrhaphy (n = 123; 41%) and interposition graft (n = 180; 59%). No differences were found between the groups in male gender (68% vs 63%), hypertension (98% vs 98%), or central stenosis (14% vs 22%). The patients who had undergone aneurysmorrhaphy were younger (median age, 54 years vs 59 years); had had a lower rate of diabetes (41% vs 59%), coronary artery disease (41% vs 58%), and congestive heart failure (41% vs 55%); and were less likely to have undergone upper arm access (72% vs 92%). The median follow-up was 11.1 months (interquartile range, 3.6-25.2 months). No differences were found in the incidence of 30-day wound complications (1% vs 3%) or surgical site infections (4% vs 6%). On multivariable Cox regression, interposition graft placement was associated with the loss of primary assisted patency (adjusted hazard ratio [aHR], 2.42; 95% confidence interval [CI], 1.18-4.95), loss of secondary patency (aHR, 3.10; 95% CI, 1.21-7.94), and abandonment of dialysis access (aHR, 3.07; 95% CI, 1.61-5.87; P < .05 for all) at 2 years.ConclusionsAVF aneurysmorrhaphy was associated with improved primary assisted and secondary patency and decreased abandonment of dialysis access. We suggest using aneurysmorrhaphy when AVF aneurysms are indicated for repair. However, individual factors such as patient comorbidities, AVF anatomy, remaining dialysis access options, and patient preference should be considered when planning the surgical approach.     

Higher center volume is significantly associated with lower mortality in trauma patients with shock

IntroductionInjured patients presenting in shock are at high risk of mortality despite numerous efforts to improve resuscitation. Identifying differences in outcomes among centers for this population could yield insights to improve performance. We hypothesized that trauma centers treating higher volumes of patients in shock would have lower risk-adjusted mortality.MethodsWe queried the Pennsylvania Trauma Outcomes Study from 2016 to 2018 for injured patients ≥16 years of age at Level I&II trauma centers who had an initial systolic blood pressure (SBP) of <90 mmHg. We excluded patients with critical head injury (abbreviated injury score [AIS] head ≥5) and patients coming from centers with a shock patient volume of ≤10 for the study period. The primary exposure was tertile of center-level shock patient volume (low, medium, or high volume). We compared risk-adjusted mortality by tertile of volume using multivariable Cox proportional hazards model incorporating age, injury severity, mechanism, and physiology.ResultsOf 1,805 included patients at 29 centers, 915 (50.7%) died. The median annual shock trauma patient volume was 9 patients for low volume centers, medium 19.5, and high 37. Median ISS was higher at high volume compared to low volume centers (22 vs 18, p <0.001). Raw mortality was 54.9% at high volume centers, 46.7% for medium, and 42.9% for low. Time elapsed from arrival to emergency department (ED) to the operating room (OR) was lower at high volume than low volume centers (median 47 vs 78 min) p = 0.003. In adjusted analysis, hazard ratio for high volume centers (referenced to low volume) was 0.76 (95% CI 0.59–0.97, p = 0.030).ConclusionAfter adjusting for patient physiology and injury characteristics, center-level volume is significantly associated with mortality. Future studies should seek to identify key practices associated with improved outcomes in high-volume centers. Furthermore, shock patient volume should be considered when new trauma centers are opened.     

Catheter use is high even among hemodialysis patients with a fistula or graft

At any given time, approximately 27% of patients in the United States (US) receive hemodialysis through a permanent catheter. However, this cross-sectional estimate may significantly underestimate the lifetime exposure of patients to hemodialysis catheters, and hence, to the excess risk of the adverse clinical events associated with catheter use. To further clarify catheter use in hemodialysis patients, we identified a cohort of fistula and graft patients in the US Renal Data System using Current Procedural Terminology (CPT) codes. Patients were included if their first hemodialysis was between 1 January 1996 and 31 December 2001, and Medicare was their primary payer. We identified permanent catheter insertions in these patients using CPT codes starting 6 months before their first hemodialysis session (or fistula or graft placement, if earlier), and ending 40 months afterward. Most patients (82%) were >65 years old, 57% were male, and 72% were white. The overall rate of permanent catheter insertions was 44 per 100 patient years, with 57% of patients having at least one catheter insertion. The percent of patients receiving a catheter was similar before (30%) and after (27%) the first fistula or graft placement. Cross-sectional analysis may significantly underestimate the lifetime risk of exposure to hemodialysis catheters. Because catheter use is common even in fistula and graft patients, measures used to prevent adverse events associated with catheter use are important in all patients regardless of current access type.     

Asymptomatic cryptococcal antigenemia is associated with mortality among HIV-positive patients in Indonesia

Introduction

Previous studies, mostly from Africa, have shown that serum cryptococcal antigenemia may precede the development of cryptococcal meningitis and early death among patients with advanced HIV infection. We examined cryptococcal antigenemia as a risk factor for HIV-associated mortality in Indonesia, which is experiencing a rapidly growing HIV epidemic.

Methods

We included ART-naïve HIV patients with a CD4 cell count below 100 cells/μL and no signs of meningitis in an outpatient HIV clinic in Bandung, West Java, Indonesia. Baseline clinical data and follow-up were retrieved from a prospective database, and cryptococcal antigen was measured in stored serum samples using a semiquantitative lateral flow assay. Cox regression analysis was used to identify factors related to mortality.

Results

Among 810 patients (median CD4 cell count 22), 58 (7.1%) had a positive cryptococcal antigen test with a median titre of 1:80 (range: 1:1 to 1:2560). Cryptococcal antigenemia at baseline was strongly associated with the development of cryptococcal meningitis and early death and loss to follow-up. After one year, both death (22.4% vs. 11.6%; p=0.016; adjusted HR 2.19; 95% CI 1.78–4.06) and the combined endpoint of death or loss to follow-up (67.2% vs. 40.4%; p<0.001; adjusted HR 1.57; 95% CI 1.12–2.20) were significantly higher among patients with a positive cryptococcal antigen test.

Conclusions

Cryptococcal antigenemia is common and clinically relevant among patients with advanced HIV in this setting. Routine screening for cryptococcal antigen followed by lumbar puncture and pre-emptive antifungal treatment for those who are positive may help in reducing early mortality.     

Arteriovenous fistula associated with adenocarcinoma of the kidney.

We present a case of a large renal arteriovenous fistula associated with an adenocarcinoma. The clinical and radiological findings are presented together with a brief review of the literature.     

Increased dietary sodium is independently associated with greater mortality among prevalent hemodialysis patients

Dietary sodium is thought to play a major role in the pathogenesis of hypertension, hypervolemia, and mortality in hemodialysis patients; hence, sodium restriction is almost universally recommended. Since the evidence upon which to base these assumptions is limited, we undertook a post-hoc analysis of 1770 patients in the Hemodialysis Study with available dietary, clinical, and laboratory information. Within this cohort, 772 were men, 1113 black, and 786 diabetic, with a mean age of 58 years and a median dietary sodium intake of 2080 mg/day. After case-mix adjustment, linear regression modeling found that higher dietary sodium was associated with a greater ultrafiltration requirement, caloric and protein intake; sodium to calorie intake ratio was associated with a greater ultrafiltration requirement; and sodium to potassium ratio was associated with higher serum sodium. No indices were associated with the pre-dialysis systolic blood pressure. Cox regression modeling found that higher baseline dietary sodium and the ratio of sodium to calorie or potassium were each independently associated with greater all-cause mortality. No association between a prescribed dietary sodium restriction and mortality were found. Thus, higher reported dietary sodium intake is independently associated with greater mortality among prevalent hemodialysis patients. Randomized trials will be necessary to determine whether dietary sodium restriction improves survival.     

Complex endovascular aneurysm repair is associated with higher perioperative mortality but not late mortality compared with infrarenal endovascular aneurysm repair among octogenarians

Objective

As our collective experience with complex endovascular aneurysm repair (EVAR) has grown, an increasing number of older patients are being offered endovascular repair of juxtarenal aneurysms. Outcomes after complex EVAR in this older subpopulation are not well-described. We sought to specifically evaluate clinical outcomes after complex EVAR compared with infrarenal EVAR in a cohort of octogenarians.

High doses of epoetin do not lower mortality and cardiovascular risk among elderly hemodialysis patients with diabetes

A randomized trial had suggested that high doses of erythropoiesis-stimulating agents (ESAs) might increase the risk of cardiovascular outcomes in predialysis diabetic patients. To evaluate this risk in diabetic patients receiving dialysis, we used data from 35,593 elderly Medicare patients on hemodialysis in the US Renal Data System of whom 19,034 were diabetic. A pooled logistic model was used to estimate the monthly probability of mortality and a composite cardiovascular end point. Inverse probability weighting was used to adjust for measured time-dependent confounding by indication, estimated separately for diabetic and non-diabetic cohorts. The adjusted 9-month mortality risk, significantly different between an ESA dose of 45,000 and 15,000?U/week, was 13% among diabetics and 5% among non-diabetics. In diabetic patients, the hazard ratio (HR) for more than 40,000?U/week was 1.32 for all-cause mortality and 1.26 for a composite end point of death and cardiovascular events compared with patients receiving 20,000 to 30,000?U/week. The corresponding HRs in non-diabetic patients were 1.06 and 1.10, respectively. A smaller effect of dose was found in non-diabetic patients. Thus, higher ESA doses, which are often necessary to achieve high hemoglobin levels, are not beneficial, and possibly harmful, to diabetic patients receiving dialysis. Our findings support a Food and Drug Administration advisory recommending that the lowest possible ESA dose be used to treat hemodialysis patients.     

Robotic-assisted radical cystectomy is associated with lower perioperative mortality in octogenarians

ObjectivesTo compare perioperative outcomes between robotic and open radical cystectomy in octogenarians using real-world dataSubjects and methodsUsing the Premier Healthcare Database, we found 13,127 patients who underwent robotic-assisted radical cystectomy (RARC) between 2008 and 2017, of which 15.1% were ≥80 years old. Perioperative mortality was the primary outcome of interest. Secondary outcomes include complications, hospital length of stay, readmission rates, and disposition after discharge. Multivariable regression analysis was used to adjust for patient and hospital characteristics.ResultsIn octogenarians, mortality at the index admission was 2.2% in those who underwent RARC, compared to 4.6% in those who underwent open surgery (P = 0.027). On multivariable analysis, robotic surgery was associated with lower in-hospital mortality in octogenarians (OR 0.46, 95% CI 0.22–0.99, P = 0.047) even after controlling for patient, and hospital characteristics.ConclusionRARC is safe and feasible in octogenarians. Elderly patients may derive more benefit from minimally invasive radical cystectomy compared to a younger cohort.     

Non-dipping is a potent predictor of cardiovascular mortality and is associated with autonomic dysfunction in haemodialysis patients.

BACKGROUND: Lack of nocturnal blood pressure (BP) fall (non-dipping) is common among haemodialysis (HD) patients, but much less is known regarding its association with cardiovascular (CV) disease morbidity and mortality. METHODS: Eighty HD patients initially underwent 24 h ambulatory BP monitoring (ABPM), and then they were defined as either 'dippers' (n=24, nocturnal BP fall > or = 10%) or 'non-dippers' (n=56, fall <10%). Coronary angiography was performed in the patients who had signs and/or symptoms of coronary artery disease (CAD). Twenty-four hour ambulatory ECG was recorded in 20 dippers and 20 non-dipper HD patients, and in 20 normal subjects. All patients were followed for up to 5.8 years (33.0+/-19.1 months). The outcome events studied were the hospitalisations due to CV diseases and CV death. RESULTS: Compared with dippers, non-dippers initially had a higher incidence of coronary artery stenosis (P<0.05) along with left ventricular asynergy (both Ps<0.01). The circadian rhythm of autonomic function was impaired in non-dippers. The incidences of CV events and CV deaths were 3.5 and 9 times higher in non-dippers than in dippers. The cumulative CV event-free survival and CV survival rates were lower in non-dippers than in dippers (P=0.02 and P=0.005, respectively). Based on Cox analysis, non-dipping was associated positively with CV events and CV mortality [hazard ratio (HR) 2.46, 95% CI 1.02-5.92, P=0.038 and HR 9.62, 95% CI 1.23-75.42, P=0.031, respectively]. Meanwhile, nocturnal systolic BP fall, diurnal systolic BP and diurnal pulse pressure were negatively associated with CV event/death. The clinic BP was not associated with CV event/death. CONCLUSIONS: The non-dipping phenomenon is closely related to a high incidence of CV diseases, a poor long-term survival and profound autonomic dysfunction. ABPM is useful in predicting long-term CV prognosis in HD patients.     

Control of hyperphosphatemia among patients with ESRD

Derangements of mineral metabolism occur during the early stages of chronic kidney disease (CKD). Hyperphosphatemia develops in the majority of patients with ESRD and has long been associated with progression of secondary hyperparathyroidism and renal osteodystrophy. More recent observational data have associated hyperphosphatemia with increased cardiovascular mortality among dialysis patients. Adequate control of serum phosphorus remains a cornerstone in the clinical management of patients with CKD not only to attenuate the progression of secondary hyperparathyroidism but also possibly to reduce the risk for vascular calcification and cardiovascular mortality. These measures include dietary phosphorus restriction, dialysis, and oral phosphate binders. Dietary restriction is limited in advanced stages of CKD. Phosphate binders are necessary to limit dietary absorption of phosphorus. Aluminum hydroxide is an efficient binder; however, its use has been nearly eliminated because of concerns of toxicity. Calcium salts are inexpensive and have been used effectively worldwide as an alternative to aluminum. Concerns of calcium overload have led to the investigation of alternatives. Currently, only two Food and Drug Administration-approved noncalcium, nonaluminum binders are available. Sevelamer hydrochloride is an exchange resin and was not as effective as calcium acetate in meeting new guideline recommendations in one double-blind clinical trial. Lanthanum carbonate is a rare earth element and has been studied less extensively. Concerns of long-term administration and toxicity exist. Furthermore, these agents are significantly more expensive than calcium salts, which may contribute to patient noncompliance.