Racial and Sex Disparities in Catheter Use and Dialysis Access in the United States Medicare Population

Care Fragmentation, Social Determinants of Health, and Postoperative Mortality in Older Veterans

INTRODUCTION

Veterans Affairs Surgical Quality Improvement Program (VASQIP) benchmarking algorithms helped the Veterans Health Administration (VHA) reduce postoperative mortality. Despite calls to consider social risk factors, these algorithms do not adjust for social determinants of health (SDoH) or account for services fragmented between the VHA and the private sector. This investigation examines how the addition of SDoH change model performance and quantifies associations between SDoH and 30-d postoperative mortality.

METHODS

VASQIP (2013-2019) cohort study in patients ≥65 y old with 2-30-d inpatient stays. VASQIP was linked to other VHA and Medicare/Medicaid data. 30-d postoperative mortality was examined using multivariable logistic regression models, adjusting first for clinical variables, then adding SDoH.

RESULTS

In adjusted analyses of 93,644 inpatient cases (97.7% male, 79.7% non-Hispanic White), higher proportions of non-veterans affairs care (adjusted odds ratio [aOR] = 1.02, 95% CI = 1.01-1.04) and living in highly deprived areas (aOR = 1.15, 95% CI = 1.02-1.29) were associated with increased postoperative mortality. Black race (aOR = 0.77, CI = 0.68-0.88) and rurality (aOR = 0.87, CI = 0.79-0.96) were associated with lower postoperative mortality. Adding SDoH to models with only clinical variables did not improve discrimination (c = 0.836 versus c = 0.835).

CONCLUSIONS

Postoperative mortality is worse among Veterans receiving more health care outside the VA and living in highly deprived neighborhoods. However, adjusting for SDoH is unlikely to improve existing mortality-benchmarking models. Reduction efforts for postoperative mortality could focus on alleviating care fragmentation and designing care pathways that consider area deprivation. The adjusted survival advantage for rural and Black Veterans may be of interest to private sector hospitals as they attempt to alleviate enduring health-care disparities.

Disparities in access to endovenous treatment options in chronic lower extremity superficial venous insufficiency: A national 7-year analysis

OBJECTIVE

The goal of this study was to analyze trends in treatment access for chronic superficial venous disease and to identify disparities in care.

METHODS

This retrospective study was exempt from institutional review board approval. The American College of Surgeon National Surgical Quality Improvement Program database was used to identify patients who underwent vein stripping (VS) and endovenous procedures for treatment of chronic superficial venous disease. Endovenous options included radiofrequency ablation (RFA) and laser ablation. Data was available from 2011 to 2018 and demographic information was extracted for each patient identified by Current Procedural Terminology codes. For all racial and ethnic groups, trend lines were plotted, and the relative rate of change was determined within each specified demographic.

RESULTS

There were 21,025 patients included in the analysis. The overall mean age was 54.2 years, and the majority of patients were female (64.8%). In total, 27.9%, 55.2%, and 16.9% patients underwent VS, RFA, and laser ablation, respectively. Patients who received laser ablation were older (P < .001). Hispanic ethnicity was associated with significantly lower odds of receiving endovascular thermal ablation (EVTA) over VS (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.64-0.78; P < .001). American Indian/Alaska Native patients were more likely to receive EVTA over VS (OR, 4.02; 95% CI, 2.48-6.86); similarly, Native Hawaiian/Pacific Islander patients were more likely to receive EVTA over VS, although this difference was not statistically significant (OR, 1.44; 95% CI, 0.93-2.27). On multinomial regression, Hispanic patients were less likely to receive RFA over VS, whereas American Indian/Alaskan Native patients were more likely to receive RFA over VS. In all racial and ethnic groups, the percentage of endovenous procedures increased, whereas vein stripping decreased.

CONCLUSIONS

Based on a hospital-based dataset, demographic indicators, including age, sex, race, and ethnicity, are associated with differences in endovenous treatments for chronic superficial venous insufficiency suggesting disparities in obtaining minimally invasive treatment options among certain patient groups.

Inherent Bias in Electronic Health Records: A Scoping Review of Sources of Bias

Objectives

1.1Biases inherent in electronic health records (EHRs), and therefore in medical artificial intelligence (AI) models may significantly exacerbate health inequities and challenge the adoption of ethical and responsible AI in healthcare. Biases arise from multiple sources, some of which are not as documented in the literature. Biases are encoded in how the data has been collected and labeled, by implicit and unconscious biases of clinicians, or by the tools used for data processing. These biases and their encoding in healthcare records undermine the reliability of such data and bias clinical judgments and medical outcomes. Moreover, when healthcare records are used to build data-driven solutions, the biases are further exacerbated, resulting in systems that perpetuate biases and induce healthcare disparities. This literature scoping review aims to categorize the main sources of biases inherent in EHRs.

Methods

1.2We queried PubMed and Web of Science on January 19th, 2023, for peer-reviewed sources in English, published between 2016 and 2023, using the PRISMA approach to stepwise scoping of the literature. To select the papers that empirically analyze bias in EHR, from the initial yield of 430 papers, 27 duplicates were removed, and 403 studies were screened for eligibility. 196 articles were removed after the title and abstract screening, and 96 articles were excluded after the full-text review resulting in a final selection of 116 articles.

Results

1.3Systematic categorizations of diverse sources of bias are scarce in the literature, while the effects of separate studies are often convoluted and methodologically contestable. Our categorization of published empirical evidence identified the six main sources of bias: a) bias arising from past clinical trials; b) data-related biases arising from missing, incomplete information or poor labeling of data; human-related bias induced by c) implicit clinician bias, d) referral and admission bias; e) diagnosis or risk disparities bias and finally, (f) biases in machinery and algorithms.

Conclusions

1.4Machine learning and data-driven solutions can potentially transform healthcare delivery, but not without limitations. The core inputs in the systems (data and human factors) currently contain several sources of bias that are poorly documented and analyzed for remedies. The current evidence heavily focuses on data-related biases, while other sources are less often analyzed or anecdotal. However, these different sources of biases add to one another exponentially. Therefore, to understand the issues holistically we need to explore these diverse sources of bias. While racial biases in EHR have been often documented, other sources of biases have been less frequently investigated and documented (e.g. gender-related biases, sexual orientation discrimination, socially induced biases, and implicit, often unconscious, human-related cognitive biases). Moreover, some existing studies lack causal evidence, illustrating the different prevalences of disease across groups, which does not per se prove the causality. Our review shows that data-, human- and machine biases are prevalent in healthcare and they significantly impact healthcare outcomes and judgments and exacerbate disparities and differential treatment. Understanding how diverse biases affect AI systems and recommendations is critical. We suggest that researchers and medical personnel should develop safeguards and adopt data-driven solutions with a "bias-in-mind" approach. More empirical evidence is needed to tease out the effects of different sources of bias on health outcomes.

Social Risk and Dialysis Facility Performance in the First Year of the ESRD Treatment Choices Model

Importance

The End-Stage Renal Disease Treatment Choices (ETC) model randomly selected 30% of US dialysis facilities to receive financial incentives based on their use of home dialysis, kidney transplant waitlisting, or transplant receipt. Facilities that disproportionately serve populations with high social risk have a lower use of home dialysis and kidney transplant raising concerns that these sites may fare poorly in the payment model.

Objective

To examine first-year ETC model performance scores and financial penalties across dialysis facilities, stratified by their incident patients' social risk.

Design, Setting, and Participants

A cross-sectional study of 2191 US dialysis facilities that participated in the ETC model from January 1 through December 31, 2021.

Exposure

Composition of incident patient population, characterized by the proportion of patients who were non-Hispanic Black, Hispanic, living in a highly disadvantaged neighborhood, uninsured, or covered by Medicaid at dialysis initiation. A facility-level composite social risk score assessed whether each facility was in the highest quintile of having 0, 1, or at least 2 of these characteristics.

Main Outcomes and Measures

Use of home dialysis, waitlisting, or transplant; model performance score; and financial penalization.

Results

Using data from 125 984 incident patients (median age, 65 years [IQR, 54-74]; 41.8% female; 28.6% Black; 11.7% Hispanic), 1071 dialysis facilities (48.9%) had no social risk features, and 491 (22.4%) had 2 or more. In the first year of the ETC model, compared with those with no social risk features, dialysis facilities with 2 or more had lower mean performance scores (3.4 vs 3.6, P = .002) and lower use of home dialysis (14.1% vs 16.0%, P < .001). These facilities had higher receipt of financial penalties (18.5% vs 11.5%, P < .001), more frequently had the highest payment cut of 5% (2.4% vs 0.7%; P = .003), and were less likely to achieve the highest bonus of 4% (0% vs 2.7%; P < .001). Compared with all other facilities, those in the highest quintile of treating uninsured patients or those covered by Medicaid experienced more financial penalties (17.4% vs 12.9%, P = .01) as did those in the highest quintile in the proportion of patients who were Black (18.5% vs 12.6%, P = .001).

Conclusions

In the first year of the Centers for Medicare & Medicaid Services' ETC model, dialysis facilities serving higher proportions of patients with social risk features had lower performance scores and experienced markedly higher receipt of financial penalties.

Health inequities in dialysis care: A scoping review

MAIN PROBLEM

We aim to look at potential gaps in current dialysis literature on inequities and explore future research that could contribute to more equitable care.

METHODS

Following guidelines from the Joanna Briggs Institute (JBI) and the Preferred Reporting Items for Systematic reviews and Meta Analyses extension for Scoping Reviews (PRISMA-ScR), we conducted a scoping review of health inequities in dialysis. PubMed and Ovid Embase were searched in July 2022 for articles published between 2016 and 2022 that examined at least one of the following NIH defined health inequities: race/ethnicity, sex/gender, LGBTQ+ identity, underserved rural populations, education level, income, and occupation status. Frequencies of each health inequity as well as trends over time of the four most examined inequities were analyzed.

RESULTS

In our sample of 69 included studies, gaps were identified in LGBTQ+ identity and patient education. Inequities pertaining to race/ethnicity, sex/gender, underserved rural populations, and income were sufficiently reported. No trends between inequities investigated over time were identified.

CONCLUSIONS

Our scoping review examined current literature on health inequities pertaining to dialysis and found gaps concerning LGBTQ+ and patients with lower levels of education. To help fill these gaps, and possibly alleviate additional burden to these patients, we recommend cultural competency training for providers and dialysis center staff as well as community-based educational programs to improve dialysis patients' health literacy.

Sex Disparities in Arteriovenous Fistula Maturation Outcomes

BACKGROUND

The end-stage kidney disease life-plan aims to individualize hemodialysis (HD) access selection in patients requiring renal replacement therapy. Paucity of data on risk factors for poor arteriovenous fistula (AVF) outcomes limits the ability of physicians to guide their patients on this decision. This is especially true for female patients, who are known to have worse AVF outcomes when compared to male patients. The goal of this study was to identify risk factors associated with poor AVF maturation outcomes in female patients that will help guide individualized access selection.

METHODS

A retrospective review of 1,077 patients that had AVF creation between 2014 and 2021 at an academic medical center was performed. Maturation outcomes were compared between 596 male and 481 female patients. Separate multivariate logistic regression models were created for the male and female cohorts to identify factors associated with unassisted maturation. AVF was considered mature if it was successfully used for HD for 4-week sessions without need for further interventions. Unassisted fistula was defined as an AVF that matured without any interventions.

RESULTS

The male patients were more likely to receive more distal HD access; 378 (63%) male versus 244 (51%) female patients had radiocephalic AVF, P < 0.001. Maturation outcomes were significantly worse in female patients; 387 (80%) AVFs matured in females and 519 (87%) in male patients, P < 0.001. Similarly, the rate of unassisted maturation was 26% (125) in female patients versus 39% (233) in male patients, P < 0.001. Mean preoperative vein diameters were similar in both groups; 2.8 ± 1.1 mm in male versus 2.7 ± 0.97 mm in female patients, P = 0.17. Multivariate logistic regression analysis of the female patients revealed that Black race (odds ratio [OR]: 0.6, 95% confidence interval [CI]: 0.4-0.9, P = 0.045), radiocephalic AVF (OR: 0.6, 95% CI: 0.4-0.9, P = 0.045), and preoperative vein diameter <2.5 mm (OR: 1.4, 95% CI: 10.33-0.901.1-1.7, P = 0.014) were independent predictors of poor unassisted maturation in this cohort. In male patients, preoperative vein diameter <2.5 mm (OR: 1.4, 95% CI: 1.2-1.7, P < 0.001) and need for HD prior to AVF creation (OR: 0.6, 95% CI: 0.3-0.9, P = 0.018) were independent predictors of poor unassisted maturation.

CONCLUSIONS

Black women with marginal forearm veins may have worse maturation outcomes, and upper arm HD access should be considered when advising patients on their end-stage kidney disease life-plan.

The effect of early conversion from central venous catheter to arteriovenous fistula on hospitalization and mortality in incident haemodialysis patients

BACKGROUND

Controversy remains as to whether initiating haemodialysis (HD) with a central venous catheter (CVC) and vascular access conversion are associated with the risk of morbidity and mortality in incident HD patients.

METHODS

At our dialysis centre, the vascular access strategy is to create an arteriovenous fistula (AVF) early and use the AVF to initiate HD. In emergency situations, HD is initiated with a CVC and subsequent conversion from a CVC to an AVF as soon as possible. The effects of early AVF conversion on hospitalization and mortality were analysed.

RESULTS

At HD initiation, 35.42% used AVF, 15.63% used CVC with immature AVF and 48.96% used CVC, and all patients were able to convert from CVC to AVF within approximately 3 months. Compared to starting HD using an AVF, using a CVC was associated with access-related hospitalizations at 2 years, regardless of whether an AVF was created before (incidence rate ratio (IRR) = 3.02, 95% CI 0.89-10.24, p = 0.03) or after (IRR = 4.10, 95% CI 1.55-10.85, p < 0.01) HD initiation. The Kaplan-Meier method showed that the 2-year survival probability was not statistically significant between the three groups (log-rank χ2 = 0.165, p = 0.921). Multivariate Cox proportional hazards regression showed that starting HD with a CVC was not associated with mortality at 2 years (p > 0.05).

CONCLUSION

In this cohort, initiating HD with a CVC was associated with more access-related hospitalizations. Under the impact of an early AVF conversion strategy, despite initiating HD with a CVC, subsequent conversion from a CVC to an AVF within approximately 3 months had no impact on all-cause mortality in incident HD patients.

Arteriovenous Graft Failure in the Veterans Health Administration: Outcome Disparities Associated with Race

Background Vascular access for ongoing hemodialysis often fails, frequently requiring repeated procedures to maintain vascular patency. While research has shown racial discrepancies in multiple aspects of renal failure treatment, there is poor understanding of how these factors might relate to vascular access maintenance procedures after arteriovenous graft (AVG) placement. Purpose To evaluate racial disparities associated with premature vascular access failure after percutaneous access maintenance procedures following AVG placement using a retrospective national cohort from the Veterans Health Administration (VHA). Materials and Methods All hemodialysis vascular maintenance procedures performed at VHA hospitals between October 2016 and March 2020 were identified. To ensure the sample represented patients who consistently used the VHA, patients without AVG placement within 5 years of their first maintenance procedure were excluded. Access failure was defined as a repeat access maintenance procedure or as hemodialysis catheter placement occurring 1-30 days after the index procedure. Multivariable logistic regression analyses were performed to calculate prevalence ratios (PRs) measuring the association between hemodialysis maintenance failure and African American race compared with all other races. Models controlled for vascular access history, patient socioeconomic status, and procedure and facility characteristics. Results In total, 1950 access maintenance procedures in 995 patients (mean age, 69 years ± 9 [SD], 1870 men) with an AVG created in one of 61 VHA facilities were identified. Most procedures involved African American patients (1169 of 1950, 60%) and patients residing in the South (1002 of 1950, 51%). Premature access failure occurred in 215 of 1950 (11%) procedures. When compared with all other races, African American race was associated with premature access site failure (PR, 1.4; 95% CI: 1.07, 1.43; P = .02). Among the 1057 procedures in 30 facilities with interventional radiology resident training programs, there was no evidence of racial disparity in the outcome (PR, 1.1; P = .63). Conclusion African American race was associated with higher risk-adjusted rates of premature arteriovenous graft failure after dialysis maintenance. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Forman and Davis in this issue.

Addressing kidney health disparities with new national policy: the time is now

End-stage kidney disease (ESKD) affects over 780,000 Americans and is associated with excess morbidity and premature death. Kidney disease health disparities are well-recognized, manifesting as ESKD overburden among racial and ethnic minority populations. Specifically, Black and Hispanic individuals have a 3.4-fold and 1.3-fold greater life risk of developing ESKD than their white counterparts. There is compelling evidence that communities of color have less opportunity to benefit from kidney-specific care throughout the course of their disease, from pre-ESKD, to ESKD home therapies and kidney transplantation. These healthcare inequities have the combined devastating impact of worse outcomes and quality of life for patients and families at a significant financial cost on the healthcare system. In the last three years, across two presidential administrations, bold, broad initiatives have been outlined that, together could lead to significant transformation in kidney health. The Advancing American Kidney Health (AAKH) initiative was established as a national framework to revolutionize kidney care but did not address health equity. More recently, the Advancing Racial Equity executive order was announced, outlining initiatives to promote equity for historically underserved communities. Building from these presidential directives, we outline strategies to address the complex issue of kidney health disparities, focusing on patient awareness, care delivery, scientific advancement, and workforce initiatives. An equity-focused framework will guide policy advancements to reduce the kidney disease burden in susceptible populations and positively impact the health and well-being of all Americans.

Study protocol of a randomized controlled trial of fistula vs. graft arteriovenous vascular access in older adults with end-stage kidney disease on hemodialysis: the AV access trial

BACKGROUND

Treatment of end-stage kidney disease (ESKD) with hemodialysis requires surgical creation of an arteriovenous (AV) vascular access-fistula (AVF) or graft (AVG)-to avoid (or limit) the use of a central venous catheter (CVC). AVFs have long been considered the first-line vascular access option, with AVGs as second best. Recent studies have suggested that, in older adults, AVGs may be a better strategy than AVFs. Lacking evidence from well-powered randomized clinical trials, integration of these results into clinical decision making is challenging. The main objective of the AV Access Study is to compare, between the two types of AV access, clinical outcomes that are important to patients, physicians, and policy makers.

METHODS

This is a prospective, multicenter, randomized controlled trial in adults ≥ 60 years old receiving chronic hemodialysis via a CVC. Eligible participants must have co-existing cardiovascular disease, peripheral arterial disease, and/or diabetes mellitus; and vascular anatomy suitable for placement of either type of AV access. Participants are randomized, in a 1:1 ratio, to a strategy of AVG or AVF creation. An estimated 262 participants will be recruited across 7 healthcare systems, with average follow-up of 2 years. Questionnaires will be administered at baseline and semi-annually. The primary outcome is the rate of CVC-free days per 100 patient-days. The primary safety outcome is the cumulative incidence of vascular access (CVC or AV access)-related severe infections-defined as access infections that lead to hospitalization or death. Secondary outcomes include access-related healthcare costs and patients' experiences with vascular access care between the two treatment groups.

DISCUSSION

In the absence of studies using robust and unbiased research methodology to address vascular access care for hemodialysis patients, clinical decisions are limited to inferences from observational studies. The goal of the AV Access Study is to generate evidence to optimize vascular access care, based on objective, age-specific criteria, while incorporating goals of care and patient preference for vascular access type in clinical decision-making.

TRIAL REGISTRATION

This study is being conducted in accordance with the tenets of the Helsinki Declaration, and has been approved by the central institutional review board (IRB) of Wake Forest University Health Sciences (approval number: 00069593) and local IRB of each participating clinical center; and was registered on Nov 27, 2020, at ClinicalTrials.gov (NCT04646226).

Vital Signs: Health Disparities in Hemodialysis-Associated Staphylococcus aureus Bloodstream Infections - United States, 2017-2020

Introduction

Racial and ethnic minorities are disproportionately affected by end-stage kidney disease (ESKD). ESKD patients on dialysis are at increased risk for Staphylococcus aureus bloodstream infections, but racial, ethnic, and socioeconomic disparities associated with this outcome are not well described.

Methods

Surveillance data from the 2020 National Healthcare Safety Network (NHSN) and the 2017-2020 Emerging Infections Program (EIP) were used to describe bloodstream infections among patients on hemodialysis (hemodialysis patients) and were linked to population-based data sources (CDC/Agency for Toxic Substances and Disease Registry [ATSDR] Social Vulnerability Index [SVI], United States Renal Data System [USRDS], and U.S. Census Bureau) to examine associations with race, ethnicity, and social determinants of health.

Results

In 2020, 4,840 dialysis facilities reported 14,822 bloodstream infections to NHSN; 34.2% were attributable to S. aureus. Among seven EIP sites, the S. aureus bloodstream infection rate during 2017-2020 was 100 times higher among hemodialysis patients (4,248 of 100,000 person-years) than among adults not on hemodialysis (42 of 100,000 person-years). Unadjusted S. aureus bloodstream infection rates were highest among non-Hispanic Black or African American (Black) and Hispanic or Latino (Hispanic) hemodialysis patients. Vascular access via central venous catheter was strongly associated with S. aureus bloodstream infections (NHSN: adjusted rate ratio [aRR] = 6.2; 95% CI = 5.7-6.7 versus fistula; EIP: aRR = 4.3; 95% CI = 3.9-4.8 versus fistula or graft). Adjusting for EIP site of residence, sex, and vascular access type, S. aureus bloodstream infection risk in EIP was highest in Hispanic patients (aRR = 1.4; 95% CI = 1.2-1.7 versus non-Hispanic White [White] patients), and patients aged 18-49 years (aRR = 1.7; 95% CI = 1.5-1.9 versus patients aged ≥65 years). Areas with higher poverty levels, crowding, and lower education levels accounted for disproportionately higher proportions of hemodialysis-associated S. aureus bloodstream infections.

Conclusions and implications for public health practice

Disparities exist in hemodialysis-associated S. aureus infections. Health care providers and public health professionals should prioritize prevention and optimized treatment of ESKD, identify and address barriers to lower-risk vascular access placement, and implement established best practices to prevent bloodstream infections.

Prevalence of Central Venous Stenosis among Black and White ESKD Patients with Dysfunctional Dialysis Access

In the United States, significant racial and ethnic disparities exist in chronic kidney disease (CKD) and its management. Hemodialysis constitutes the main stay of renal replacement therapy for end-stage kidney disease (ESKD), which is initiated using central venous catheters (CVC) in most CKD patients in the United States. Black ESKD patients have higher usage and greater time on CVC for hemodialysis compared to White patients. This trend places Black patients at a potentially higher risk for CVC-related complications such as central venous stenosis (CVS). We posited that Black patients would have a higher prevalence and a greater risk of CVS. A retrospective review was performed of ESKD patients who underwent a fistulogram for dialysis access malfunction. CVS was defined as > 50% stenosis in the central veins. Fistulograms of 428 ESKD patients were adjudicated, and CVS was noted in 167 of these patients. Of the entire cohort, 370 fistulograms belonged to self-reported unique Black and White ESKD patients, of whom 137 patients were noted to have CVS. There was no difference in the of CVS between Black (40%) and White (41%) ESKD patients. However, a higher severity of stenosis (>70%) (P = 0.03) was noted in White ESKD patients. An unadjusted model showed a significant association between CVS and cardiovascular disease and the use of CVCs. The risk-adjusted model showed a significant association between diabetes and CVS. Unlike arterial stenotic lesions, this work for the first time demonstrated higher prevalence of severe venous stenotic lesions in White ESKD patients and linked diabetes to stenotic venous disease. This work paves the way for future studies investigating the risk and influence of race and ethnicity on CVS using a larger and diverse data set.

Is there sex disparity in vascular access at dialysis initiation in France? A mediation analysis using the data of the REIN registry

Background

This study was conducted to estimate the direct effect of sex on the proportion of hemodialysis catheters at dialysis initiation and to investigate whether predialysis care or socioeconomic status acted as a mediator of the sex effect.

Methods

Patients who started dialysis between 01–01-2017 and 30–06-2018 in France were included using the data of the REIN registry. Logistic regression was performed to study the association between sex and the proportion of HD catheters. A mediation analysis with a counterfactual approach was carried out to evaluate whether there was an indirect effect of gender through the proxies of predialysis care (hemoglobin, albumin levels, glomerular filtration rate (GFR) at dialysis initiation) and socioeconomic status. Due to the identification of an interaction between gender and social deprivation, a subgroup analysis was performed among deprived and nondeprived patients.

Results

There were 16 032 patients included, and the sex ratio (M/F) was 10 405/5627. In the multivariable analysis, women were associated with a greater risk of starting dialysis with a catheter (OR 1.32 [95% CI: 1.23–1.42]). There was an indirect effect of sex on the proportion of HD catheters through proxies for predialysis care (albuminemia &lt; 30 g/L (OR 1.08 [95% CI: 1.05–1.10]), hemoglobin &lt; 11 g/dL (OR 1.03 [95% CI: 1.02–1.04]), GFR &lt; 7 ml/min (OR 1.05 [95% CI: 1.04–1.07])). Among deprived patients, there was no direct effect of sex on the catheter proportion.

Conclusions

Women were associated with a higher risk of starting dialysis through an HD catheter. The effect of sex was mediated by predialysis care, particularly for deprived patients.

Racial Disparities in Arteriovenous Fistula Use Among Hemodialysis Patients: The Role of Surgeon Supply

Introduction

Factors contributing to racial disparities in arteriovenous fistula (AVF) use among hemodialysis (HD) patients remain poorly defined. We evaluated whether the Black/White race disparity in AVF use is affected by vascular access surgeon supply.

Methods

Using Consolidated Renal Operations in a Web-Enabled Network (CROWNWeb) and Medicare claims data from the US Renal Data System (USRDS), competing risk analyses of all US patients initiating HD with a central venous catheter (CVC) from 2016 to 2017 (n = 100,227) were performed. The likelihood of successful AVF use was compared between Black and White patients after adjusting for vascular access surgeon supply.

Results

Compared with the first (lowest) quartile of surgeon supply, higher supply levels were associated with modestly increased adjusted likelihoods of overall AVF use: 4% (95% CI 1.4%-7.2%), 4% (95% CI 1.4%-7.1%), and 3% (0.0%-6.1%) for second, third, and fourth quartiles, respectively. Although areas with lower surgeon supply had a higher proportion of Black patients, residing in areas with a greater surgeon supply was not significantly associated with a mitigation in racial disparity. Specifically, compared with White patients, Black patients were 10% (95% CI 7%-13%) and 8% (95% CI 5%-11%) less likely to have successful AVF use in lower and higher surgeon supply areas, respectively.

Conclusion

Regions with lower surgeon supply had a higher proportion of Black dialysis patients. However, racial disparities in AVF use among patients initiating HD with a CVC were similar in regions with a high and low surgeon supply. Other patient, provider, and practice factors should be evaluated toward mitigating lower rates of AVF use among Black HD patients.

Performance of Multiple Pretrained BERT Models to Automate and Accelerate Data Annotation for Large Datasets

PURPOSE

To develop and evaluate domain-specific and pretrained bidirectional encoder representations from transformers (BERT) models in a transfer learning task on varying training dataset sizes to annotate a larger overall dataset.

MATERIALS AND METHODS

The authors retrospectively reviewed 69 095 anonymized adult chest radiograph reports (reports dated April 2020-March 2021). From the overall cohort, 1004 reports were randomly selected and labeled for the presence or absence of each of the following devices: endotracheal tube (ETT), enterogastric tube (NGT, or Dobhoff tube), central venous catheter (CVC), and Swan-Ganz catheter (SGC). Pretrained transformer models (BERT, PubMedBERT, DistilBERT, RoBERTa, and DeBERTa) were trained, validated, and tested on 60%, 20%, and 20%, respectively, of these reports through fivefold cross-validation. Additional training involved varying dataset sizes with 5%, 10%, 15%, 20%, and 40% of the 1004 reports. The best-performing epochs were used to assess area under the receiver operating characteristic curve (AUC) and determine run time on the overall dataset.

RESULTS

The highest average AUCs from fivefold cross-validation were 0.996 for ETT (RoBERTa), 0.994 for NGT (RoBERTa), 0.991 for CVC (PubMedBERT), and 0.98 for SGC (PubMedBERT). DeBERTa demonstrated the highest AUC for each support device trained on 5% of the training set. PubMedBERT showed a higher AUC with a decreasing training set size compared with BERT. Training and validation time was shortest for DistilBERT at 3 minutes 39 seconds on the annotated cohort.

CONCLUSION

Pretrained and domain-specific transformer models required small training datasets and short training times to create a highly accurate final model that expedites autonomous annotation of large datasets.Keywords: Informatics, Named Entity Recognition, Transfer Learning Supplemental material is available for this article. ©RSNA, 2022See also the commentary by Zech in this issue.

Healthcare disparities in vascular surgery: A critical review

Health disparities in vascular surgical care have existed for decades. Persons categorized as Black undergo a nearly twofold greater risk-adjusted rate of leg amputations. Persons categorized as Black, Latinx, and women have hemodialysis initiated via autogenous fistula less often than male persons categorized as White. Persons categorized as Black, Latino, Latina, or Latinx, and women are less likely to undergo carotid endarterectomy for symptomatic carotid stenosis and repair of abdominal aortic aneurysms. New approaches are needed to address these disparities. We suggest surgeons use data to identify groups that would most benefit from medical care and then partner with community organizations or individuals to create lasting health benefits. Surgeons alone cannot rectify the structural inequalities present in American society. However, all surgeons should contribute to ensuring that all people have access to high-quality vascular surgical care.

Race, Education, and Gender Disparities in Transplantation of Kidneys From Hepatitis C Viremic Donors

BACKGROUND

Transplantation of kidneys from hepatitis C virus (HCV)-viremic donors into HCV-negative patients followed by direct-acting antiviral therapy was an important breakthrough to increase the number of life-saving kidney transplants. Data suggest that these transplants offer several benefits; however, it is unknown whether adoption of this practice has been shared equitably, especially among disadvantaged groups.

METHODS

We evaluated United Network for Organ Sharing data on HCV-seronegative adult deceased-donor kidney transplant recipients from January 1, 2017, to June 12, 2020. We compared recipients of a kidney from an HCV antibody- (Ab-)/nucleic acid test- (NAT-), HCV Ab+/NAT-, and HCV NAT+ donor. The primary covariates were as follows: (1) race/ethnicity; (2) female sex; and (3) highest level of education. Models included variables associated with being offered an HCV NAT+ kidney. We fit mixed-effects multinomial logistic regression models with the center as a random effect to account for patient clustering.

RESULTS

Of 48 255 adult kidney-alone deceased-donor kidney transplant HCV-seronegative recipients, 1641 (3.4%) donors were HCV NAT+-, increasing from 0.3% (January 2017-June 2017) to 6.9% (January 2020-June 2020). In multivariable models, racial/ethnic minorities, women, and those with less education were significantly less likely to receive a kidney from an HCV NAT+ donor relative to an HCV Ab-/NAT- and HCV Ab+/NAT- donor. The disparities were most pronounced among Hispanic and Asian patients with less educational attainment (grade school, high school, or some college/tech school).

CONCLUSIONS

Despite an increase in transplants from HCV NAT+ donors, we found substantial racial/ethnic disparities in transplantation of these kidneys. These data highlight how the benefits of a scientific breakthrough are often made less available to disadvantaged patients.

Sex-related disparities in intervention rates and type of intervention in patients with aortic and peripheral arterial diseases in the National Inpatient Sample Database

OBJECTIVE

The first annual Women's Vascular Summit highlighted sex- and gender-related knowledge gaps in vascular disease diagnosis and treatment. This finding suggests an opportunity for further research to improve care and outcomes in people who identify as women, specifically. The purpose of this study was to a large national dataset to identify all operations performed for abdominal aortic aneurysm (AAA), carotid artery stenosis (CAS), and peripheral arterial disease (PAD) in the United States, and to provide data on sex-related disparities in treatment.

METHODS

All hospitalizations of adult patients (≥18 years old) diagnosed with AAA, CAS, or PAD who underwent vascular surgery from 2000 to 2016 were identified in the Healthcare Cost and Utilization Project National Inpatient Sample. Sex-stratified U.S. Census data and sex-specific population disease prevalence estimates from the National Institute of Health and Agency for Healthcare Research and Quality were used to calculate the number of U.S. adults with AAA, CAS, and PAD. Sex-stratified rates of surgery and incidence rate ratios were estimated using Poisson regression. Among those undergoing surgery, multivariable logistic regression was used to assess differences in endovascular vs open approach.

RESULTS

Over 16 years, there were 1,021,684 hospitalizations for vascular surgery: 13% AAA (21% female, 79% male), 40% CAS (42% female, 58% male), and 47% PAD (42% female, 58% male). Females were older than males at time of surgery (median age, 71.3 years vs 69.7 years) and less likely to have private insurance (18% vs 23%); minimal differences were seen across race/ethnicity, comorbidities, and hospital characteristics. After accounting for disease prevalence, females were still 25% less likely to undergo surgery for AAA and 30% less likely to undergo surgery for PAD compared with males with the same disease. These results were consistent over time. After adjustment, females, compared with males, were less likely to receive an endovascular procedure compared with open for AAA or CAS, and more likely to receive one for PAD.

CONCLUSIONS

From 2000 to 2016 in the United States, females were less likely to undergo intervention for AAA and PAD than males. This finding is particularly significant for PAD, because the prevalence is the same for both sexes, indicating that females are likely undertreated for PAD. Additionally, females were less likely to undergo endovascular surgery for AAA and more likely to undergo endovascular surgery for PAD than males. These findings suggest that improvement in AAA and PAD identification and management in females may improve outcomes.

Racial Disparities in the Arteriovenous Fistula Care Continuum in Hemodialysis Patients

BACKGROUND AND OBJECTIVES

Arteriovenous fistulas are the optimal vascular access type for patients on hemodialysis. However, arteriovenous fistulas are used less frequently in Black than in White individuals. The arteriovenous fistula care continuum comprises a series of sequential steps. A better understanding is needed of where disparities exist along the continuum in order to mitigate racial differences in arteriovenous fistula use.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using Medicare claims data from the United States Renal Data System, longitudinal analyses of patients ≥67 years initiating hemodialysis with a central venous catheter between July 1, 2010 and June 30, 2012 were performed. Three patient cohorts were identified: patients initiating hemodialysis with a catheter (n=41,814), patients with arteriovenous fistula placement within 6 months of dialysis initiation (n=14,077), and patients whose arteriovenous fistulas were successfully used within 6 months of placement (n=7068). Three arteriovenous fistula processes of care outcomes were compared between Blacks and Whites: (1) arteriovenous fistula creation, (2) successful arteriovenous fistula use, and (3) primary arteriovenous fistula patency after successful use.

RESULTS

An arteriovenous fistula was placed within 6 months of dialysis initiation in 37% of patients initiating dialysis with a catheter. Among the patients with arteriovenous fistula placement, the arteriovenous fistula was successfully used for dialysis within 6 months in 48% of patients. Among patients with successful arteriovenous fistula use, 21% maintained primary arteriovenous fistula patency at 3 years. After adjusting for competing risks, Black patients on hemodialysis were 10% less likely to undergo arteriovenous fistula placement (adjusted subdistribution hazard ratio, 0.90; 95% confidence interval, 0.87 to 0.94); 12% less likely to have successful arteriovenous fistula use after placement (adjusted subdistribution hazard ratio, 0.88; 95% confidence interval, 0.83 to 0.93); and 22% less likely to maintain primary arteriovenous fistula patency after successful use (subdistribution hazard ratio, 0.78; 95% confidence interval, 0.74 to 0.84).

CONCLUSIONS

Lower arteriovenous fistula use among Blacks older than 67 years of age treated with hemodialysis was attributable to each step along the continuum of arteriovenous fistula processes of care.