Influence of race, ethnicity and socioeconomic status on kidney disease

Sex-Specific Association of Ambient Temperature With Urine Biomarkers in Southwest Coastal Bangladesh

Introduction

Men are vulnerable to ambient heat-related kidney disease burden; however, limited evidence exists on how vulnerable women are when exposed to high ambient heat. We evaluated the sex-specific association between ambient temperature and urine electrolytes, and 24-hour urine total protein, and volume.

Methods

We pooled a longitudinal 5624 person-visits data of 1175 participants' concentration and 24-hour excretion of urine electrolytes and other biomarkers (24-hour urine total protein and volume) from southwest coastal Bangladesh (Khulna, Satkhira, and Mongla districts) during November 2016 to April 2017. We then spatiotemporally linked ambient temperature data from local weather stations to participants' health outcomes. For evaluating the relationships between average ambient temperature and urine electrolytes and other biomarkers, we plotted confounder-adjusted restricted cubic spline (RCS) plots using participant-level, household-level, and community-level random intercepts. We then used piece-wise linear mixed-effects models for different ambient temperature segments determined by inflection points in RCS plots and reported the maximum likelihood estimates and cluster robust standard errors. By applying interaction terms for sex and ambient temperature, we determined the overall significance using the Wald test. Bonferroni correction was used for multiple comparisons.

Results

The RCS plots demonstrated nonlinear associations between ambient heat and urine biomarkers for males and females. Piecewise linear mixed-effects models suggested that sex did not modify the relationship of ambient temperature with any of the urine parameters after Bonferroni correction (P < 0.004).

Conclusion

Our findings suggest that women are as susceptible to the effects of high ambient temperature exposure as men.

Demographic distribution analysis of different glomerular diseases in Southwest China from 2008 to 2022

BACKGROUND

Environmental and lifestyle factors play an etiological role in the pathogenesis of different glomerular diseases. Thus, exploring the epidemic characteristics of renal disease in different nationalities and regions is important.

MATERIALS AND METHODS

Patients who underwent renal biopsy from October 2008 to October 2022 were included. The proportion and change tendency of glomerular diseases and the differences between the sexes and different ages and races were analyzed.

RESULTS

There were 15,146 cases of glomerular diseases (98.5%), involving 7538 males (49.8%) and 7608 females (50.2%). The mean age was 37.0 years (range 0-80 years). The proportion of membranous nephropathy (MN) and diabetic nephropathy (DN) showed an increased trend. The most common primary glomerulonephritis (PGN) was IgA nephropathy (IgAN, 44.6%), followed by minimal-change disease (MCD, 24.3%) and MN (15.4%). Lupus nephritis (LN, 30%) accounted for the largest proportion of SGNs, followed by Henoch-Schonlein purpura nephritis (HSPN, 20.9%) and DN (19.8%). Compared with adults aged 18-60 years old, MCD and HSPN were more common in children and MN and DN in elderly individuals, statistically significant differences. Additionally, the sex and age distribution of PGN and SGN between the Tibetan and Han populations differed significantly, whereby LN was higher in the Han population and HSPN in the Tibetan population.

CONCLUSION

The distribution of glomerular diseases showed age, sex and race differences. This research will be beneficial for providing epidemiological evidence for clinical diagnosis, disease prevention and public health decision-making.

Socioeconomic Position and Health Among Children and Adolescents With CKD Across the Life-Course

Children and adolescents in families of lower socioeconomic position (SEP) experience an inequitable burden of reduced access to healthcare and poorer health. For children living with chronic kidney disease (CKD), disadvantaged SEP may exacerbate their considerable disease burden. Across the life-course, CKD may also compromise the SEP of families and young people, leading to accumulating health and socioeconomic disadvantage. This narrative review summarizes the current evidence on relationships of SEP with kidney care and health among children and adolescents with CKD from a life-course approach, including impacts of family SEP on kidney care and health, and bidirectional impacts of CKD on SEP. It highlights relevant conceptual models from social epidemiology, current evidence, clinical and policy implications, and provides directions for future research. Reflecting the balance of available evidence, we focus primarily on high-income countries (HICs), with an overview of key issues in low- and middle-income countries (LMICs). Overall, a growing body of evidence indicates sobering socioeconomic inequities in health and kidney care among children and adolescents with CKD, and adverse socioeconomic impacts of CKD. Dedicated efforts to tackle inequities are critical to ensuring that all young people with CKD have the opportunity to live long and flourishing lives. To prevent accumulating disadvantage, the global nephrology community must advocate for local government action on upstream social determinants of health; and adopt a life-course approach to kidney care that proactively identifies and addresses unmet social needs, targets intervening factors between SEP and health, and minimizes adverse socioeconomic outcomes across financial, educational and vocational domains.

Neighborhood Segregation and Access to Live Donor Kidney Transplantation

Importance

Identifying the mechanisms of structural racism, such as racial and ethnic segregation, is a crucial first step in addressing the persistent disparities in access to live donor kidney transplantation (LDKT).

Objective

To assess whether segregation at the candidate's residential neighborhood and transplant center neighborhood is associated with access to LDKT.

Design, Setting, and Participants

In this cohort study spanning January 1995 to December 2021, participants included non-Hispanic Black or White adult candidates for first-time LDKT reported in the US national transplant registry. The median (IQR) follow-up time for each participant was 1.9 (0.6-3.0) years.

Main Outcome and Measures

Segregation, measured using the Theil H method to calculate segregation tertiles in zip code tabulation areas based on the American Community Survey 5-year estimates, reflects the heterogeneity in neighborhood racial and ethnic composition. To quantify the likelihood of LDKT by neighborhood segregation, cause-specific hazard models were adjusted for individual-level and neighborhood-level factors and included an interaction between segregation tertiles and race.

Results

Among 162 587 candidates for kidney transplant, the mean (SD) age was 51.6 (13.2) years, 65 141 (40.1%) were female, 80 023 (49.2%) were Black, and 82 564 (50.8%) were White. Among Black candidates, living in a high-segregation neighborhood was associated with 10% (adjusted hazard ratio [AHR], 0.90 [95% CI, 0.84-0.97]) lower access to LDKT relative to residence in low-segregation neighborhoods; no such association was observed among White candidates (P for interaction = .01). Both Black candidates (AHR, 0.94 [95% CI, 0.89-1.00]) and White candidates (AHR, 0.92 [95% CI, 0.88-0.97]) listed at transplant centers in high-segregation neighborhoods had lower access to LDKT relative to their counterparts listed at centers in low-segregation neighborhoods (P for interaction = .64). Within high-segregation transplant center neighborhoods, candidates listed at predominantly minority neighborhoods had 17% lower access to LDKT relative to candidates listed at predominantly White neighborhoods (AHR, 0.83 [95% CI, 0.75-0.92]). Black candidates residing in or listed at transplant centers in predominantly minority neighborhoods had significantly lower likelihood of LDKT relative to White candidates residing in or listed at transplant centers located in predominantly White neighborhoods (65% and 64%, respectively).

Conclusions

Segregated residential and transplant center neighborhoods likely serve as a mechanism of structural racism, contributing to persistent racial disparities in access to LDKT. To promote equitable access, studies should assess targeted interventions (eg, community outreach clinics) to improve support for potential candidates and donors and ultimately mitigate the effects of segregation.

Relationships, race/ethnicity, gender, age, and living kidney donation evaluation willingness

Racial/ethnic and gender disparities in living donor kidney transplantation are large and persistent but incompletely explained. One previously unexplored potential contributor to these disparities is differential willingness to donate to recipients in specific relationships such as children, parents, and friends. We collected and analyzed data from an online sample featuring an experimental vignette in which respondents were asked to rate their willingness to donate to a randomly chosen member of their family or social network. Results show very large differences in respondents' willingness to donate to recipients with different relationships to them, favoring children, spouses/partners, siblings, and parents, and disfavoring friends, aunts/uncles, and coworkers. Evidence suggesting an interactive effect between relationship, respondent race/ethnicity, respondent or recipient gender, was limited to a few cases. At the p < 0.05 level, the parent-recipient gender interaction was statistically significant, favoring mothers over fathers, as was other/multiracial respondents' greater willingness to donate to friends compared to Whites. Additionally, other interactions were significant at the p < 0.10 level, such as Hispanics' and women's higher willingness to donate to parents compared to Whites and men respectively, women's lower willingness to donate to friends compared to men, and Blacks' greater willingness to donate to coworkers than Whites. We also examined differences by age and found that older respondents were less willing to donate to recipients other than their parents. Together these results suggest that differential willingness to donate by relationship group may be a moderately important factor in understanding racial/ethnic and gender disparities in living donor kidney transplantation.

Enhancing Quality of Life in African American Patients with Chronic Kidney Disease: An Evidence-Based Intervention

This study aimed to assess the effectiveness of achronic kidney disease (CKD) peer coach's educational intervention on the quality of life of African-American individuals with CKD. This study employed an experimental research design to assess a peer coaching educational intervention for African-American individuals with CKD. The theoretical underpinning was grounded in social learning theory, emphasizing observational learning, imitation, and modeling. 165 patients were randomly assigned to either the intervention group (n = 81) or the control group (n = 84). Pre- and post-intervention analyses showed no significant differences in most health measures between the two groups. However, the intervention group demonstrated significant improvement in the energy/fatigue subscale, witha16-point difference supporting the intervention group (p = .003). Additionally, the intervention group showed increased scores in the pain subscale (p = .015), while the control group did not. The CKD educational intervention highlighted cultural considerations and provided cost-effective strategies for social workers. It emphasizes the importance of targeted educational interventions and calls for further research and interventions to address the comprehensive needs of CKD patients and improve their quality of life.

Implementation of the ASCENT Trial to Improve Transplant Waitlisting Access

Introduction

The Allocation System for changes in Equity in Kidney Transplantation (ASCENT) study was a hybrid type 1 trial of a multicomponent intervention among 655 US dialysis facilities with low kidney transplant waitlisting to educate staff and patients about kidney allocation system (KAS) changes and increase access to and reduce racial disparities in waitlisting. Intervention components included a staff webinar, patient and staff educational videos, and facility-specific feedback reports.

Methods

Implementation outcomes were assessed using the Reach, Effectiveness, Adoption, Implementation, and Maintenance Framework. Postimplementation surveys were administered among intervention group facilities (n = 334); interviews were conducted with facility staff (n = 6). High implementation was defined as using 3 to 4 intervention components, low implementation as using 1 to 2 components, and nonimplementation as using no components.

Results

A total of 331 (99%) facilities completed the survey; 57% were high implementers, 31% were low implementers, and 12% were nonimplementers. Waitlisting events were higher or similar among high versus low implementer facilities for incident and prevalent populations; for Black incident patients, the mean proportion waitlisted in low implementer facilities was 0.80% (95% confidence interval [CI]: 0.73-0.87) at baseline and 0.55% at 1-year (95% CI: 0.48-0.62) versus 0.83% (95% CI: 0.78-0.88) at baseline and 1.40% at 1-year (95% CI: 1.35-1.45) in high implementer facilities. Interviews revealed that the intervention helped facilities prioritize transplant education, but that intervention components were not uniformly shared.

Conclusion

The findings provide important context to interpret ASCENT effectiveness results and identified key barriers and facilitators to consider for future modification and scale-up of multilevel, multicomponent interventions in dialysis settings.

Kidney function decline is associated with mortality events: over a decade of follow-up from Tehran Lipid and Glucose Study

BACKGROUND

To investigate the association between estimated glomerular filtration rate (eGFR) change and mortality risk in a cohort from the Middle East and North Africa region with increasing chronic kidney disease burden.

METHODS

We included 2210 participants aged ≥ 50 years from the prospective cohort of the Tehran Lipid and Glucose Study. The interval for eGFR measurement was between the examinations in 2002-2005 to 2009-2011, and participants were followed through March 2018. Glomerular filtration rate was estimated from serum creatinine using the CKD-EPI creatinine equation. We assessed the association of rapid kidney function decline, (defined as annual eGFR decline ≥ 3 ml/min/1.73 m2 per year); ≥ 30% eGFR decline over six years; and certain drop in kidney function (≥ 25% eGFR decline plus drop in eGFR category) with mortality outcomes.

RESULTS

During a median follow-up of 14.3 years after recruitment, 315 all-cause and 112 cardiovascular disease deaths were recorded. The multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of all-cause death for rapid kidney function decline, ≥ 30% decline in eGFR over 6 years, and drop in kidney function were 1.68 (1.24-2.27), 2.01 (1.46-2.78), and 1.49 (1.11-1.98), respectively. The HRs of all-cause death and for rapid kidney function decline in those without and with chronic kidney disease were 1.41 (1.03-1.91) and 3.38 (1.69-6.76), respectively. Similar findings were observed regarding cardiovascular disease-related and non-cardiovascular disease-related mortality.

CONCLUSIONS

Estimated GFR decline is associated with an increased mortality risk, indicating its ability to provide additional prognostic information beyond traditional risk predictors in the general population.

The Haemodialysis Session Effect on the Choroidal Thickness and Retinal and Choroidal Microcirculation-A Literature Review

Haemodialysis (HD) is currently the most commonly used method of renal replacement therapy. The process of dialysis involves numerous changes that affect many systems, including the eye. The changes occurring in the course of HD may affect the ocular parameters, such as intraocular pressure, central corneal thickness, retinal thickness, retinal nerve fibre layer thickness, and choroidal thickness (CT). The choroid, being one of the most vascularized tissues, is characterized by the highest ratio of blood flow to tissue volume in the entire body, may be particularly susceptible to changes occurring during HD, and at the same time reflect the microcirculatory status and its response to HD. Patients with end-stage renal disease subjected to dialysis are highly susceptible to systemic microvascular dysfunction. Moreover, it is considered that the process of HD itself contributes to vascular dysfunction. Nowadays, thanks to the development of imaging techniques, the widely available optical coherence tomography (OCT) tests allow for the assessment of CT, while OCT-angiography allows for a quick, non-invasive, and repeatable assessment of the condition of retinal and choroidal microcirculation, which significantly expands our knowledge regarding the reaction of ocular microcirculation due to HD. The assessment of both retinal and choroidal circulation is even more attractive because retinal circulation is autoregulated, while choroidal circulation is mainly controlled by extrinsic autonomic innervation. Thus, assessment of the choroidal response to an HD session may provide the possibility to indirectly evaluate the functions of the autonomic system in patients subjected to HD. At a time when the importance of microcirculation in systemic and renal diseases is becoming increasingly evident, the assessment of ocular microcirculation appears to be a potential biomarker for assessing the condition of systemic microcirculation. In this work, we present a review of the literature on the effect of the HD session on CT and the retinal and choroidal microcirculation.

Sex/Gender-Based Disparities in Early Transplant Access by Attributed Cause of Kidney Disease-Evidence from a Multiregional Cohort in the Southeast United States

Introduction

We examined sex/gender disparities across the continuum of transplant care by attributed cause of end-stage kidney disease (ESKD).

Methods

All adults (18-79 years; N = 43,548) with new-onset ESKD in Georgia, North Carolina, or South Carolina between 2015 and 2019 were identified from the United States Renal Data System (USRDS). Individuals were linked to the Early Steps to Transplant Access Registry (E-STAR) to obtain data on referral and evaluation. Waitlisting data was ascertained from USRDS. Using a Cox-proportional hazards model, with follow-up through 2020, we assessed the association between sex/gender and referral within 12 months (among all incident dialysis patients), evaluation start within 6 months (among referred patients), and waitlisting (among all evaluated patients) by attributed cause of ESKD (type 1 diabetes mellitus, type 2 diabetes mellitus, hypertension, glomerulonephritis, cystic disease, and other).

Results

Overall, women (vs. men) with type 2 diabetes-attributed ESKD were 13% (crude hazard ratio [HR]: 0.87 [0.83-0.91]), 14% (crude HR: 0.86 [0.81-0.91]), and 14% (crude HR: 0.86 [0.78-0.94]) less likely to be referred, evaluated, and waitlisted, respectively. Women (vs. men) with hypertension-attributed ESKD were 14% (crude HR: 0.86 [0.82-0.90]) and 8% (crude HR: 0.92 [0.87-0.98]) less likely to be referred and evaluated, respectively, but similarly likely to be waitlisted once evaluated (crude HR: 1.06 [0.97-1.15]). For all other attributed causes of ESKD, there was no sex/gender disparity in referral, evaluation, or waitlisting rates.

Conclusion

In the Southeast United States, sex/gender disparities in early access to kidney transplantation are specific to people with ESKD attributed to type 2 diabetes and hypertension.

Individual- and Community-Level Socioeconomic Status and Deceased Donor Renal Transplant Outcomes

BACKGROUND

This study examined the relationship between socioeconomic status (SES), race, and ethnicity and clinical outcomes following deceased donor kidney transplant (DDKT) at a high-volume transplant center.

METHODS

This retrospective cohort study used regression models and survival analyses to examine the relationship between individual- and community-level SES, race, and ethnicity and DDKT outcomes (i.e., delayed graft function, graft failure, mortality) adjusting for potential confounders.

RESULTS

The analytic sample included 3366 patients; 40.7% (n = 1370) were female, the mean age was 54.7 (SD = 13.3) years, 49.3% were non-Hispanic White, and the median follow-up time was 39.5 months (IQR = 24.2-68.1). Patients living in the most disadvantaged communities (using the US Census data) had a higher likelihood of delayed graft function (adjusted relative risk [RR] = 1.12, p = 0.042) and a higher hazard of mortality (adjusted hazard ratio [HR] = 1.32, p = 0.025) compared to patients living in the least disadvantaged communities. Patients without a high school diploma had a higher risk of delayed graft function compared to patients with an associate degree or more (RR = 1.37, p < 0.001). Patients with public insurance coverage had a higher risk of delayed graft function (RR = 1.24, p < 0.001) and a higher hazard of mortality (HR = 1.37, p < 0.001) and graft failure (HR = 1.71, p < 0.001) compared to patients without public insurance. There were no differences in graft failure or mortality by race and ethnicity.

CONCLUSIONS

SES was not consistently associated with outcomes following DDKT; however, many of the predictors were associated with delayed graft function. With a large and diverse sample size, these findings further the heterogeneity of the present renal transplant research suggesting the need for further investigation to guide implementation of innovative strategies and interventions.

Risk of kidney failure in patients with systemic sclerosis: a nationwide population-based study

OBJECTIVE

Data from a decade ago have shown that patients with systemic sclerosis (SSc) have a higher risk of kidney failure than the general population. However, as the incidence of kidney failure due to SSc has been declining, the comparative risk of kidney failure between patients with SSc and the general population could have changed over time. We investigated the risk of kidney failure in patients with SSc compared with the general population, up to more recent years.

METHODS

This was a nationwide population-based study using the Korean National Health Insurance Service database. Patients with claims data for SSc between 2010 and 2017 (n=2591) and 1:5 age-matched and sex-matched controls (n=12 955) were selected. The index date was the earliest date of claim for SSc between 2010 and 2017. The follow-up duration was from the index date to 2019. The adjusted HRs (aHRs) and 95% CI for kidney failure were estimated using multivariable Cox proportional hazard models.

RESULTS

Over 5.2±2.6 years, the incidence rates of kidney failure in patients with SSc and controls were 2.88 and 0.35 per 1000 person-years, respectively. Patients with SSc had a significantly higher risk of kidney failure than controls (aHR=7.244, 95% CI=4.256 to 12.329). The effect size was larger in patients diagnosed with SSc between 2014 and 2017 (aHR=9.754, 95% CI=3.254 to 29.235) than in those diagnosed before 2010 (aHR=6.568, 95% CI=2.711 to 15.571) or between 2010 and 2013 (aHR=6.553, 95% CI=2.721 to 15.781).

CONCLUSION

The risk of kidney failure remains higher in patients with SSc than in the general population.

Demographic Disparities in the Incidence, Clinical Characteristics, and Outcome of Posterior Reversible Encephalopathy Syndrome in the United States

OBJECTIVES

To estimate age-specific, sex-specific, and race-specific incidence of posterior reversible encephalopathy syndrome (PRES) in the United States.

METHODS

We conducted a retrospective cohort study using the State Inpatient Database of Florida (2016-2019), Maryland (2016-2019), and New York (2016-2018). All new cases of PRES in adults (18 years or older) were combined with Census data to compute incidence. We evaluated the generalizability of incident estimates to the entire country using the 2016-2019 National Readmissions Database (NRD).

RESULTS

Across the study period, there were 3,716 incident hospitalizations for PRES in the selected states. The age-standardized and sex-standardized incidence of PRES was 2.7 (95% CI 2.5-2.8) cases/100,000/y. Incidence in female patients was >2 times that of male patients (3.7 vs 1.6 cases/100,000/y, p < 0.001). Incidence increased with age in both sexes (p-trend <0.001). Similar demographic distribution of first hospitalization for PRES was also noted in the entire country using the NRD. Age-standardized and sex-standardized PRES incidence in Black patients (4.2/100,000/y) was significantly greater than in Non-Hispanic White (2.7/100,000/y) and Hispanic patients (1.2/100,000/y) (p < 0.001 for pairwise comparisons).

DISCUSSION

The incidence of PRES in the United States is approximately 3/100,000/y, but incidence in female patients is >2 times that of male patients. PRES incidence is higher in Black compared with non-Hispanic White and Hispanic patients.

Partnering with patients and caregivers to enrich research and care in kidney disease: values and strategies

Patient and caregiver involvement broadens the scope of new knowledge generated from research and can enhance the relevance, quality and impact of research on clinical practice and health outcomes. Incorporating the perspectives of people with lived experience of chronic kidney disease (CKD) affords new insights into the design of interventions, study methodology, data analysis and implementation and has value for patients, healthcare professionals and researchers alike. However, patient involvement in CKD research has been limited and data on which to inform best practice is scarce. A number of frameworks have been developed for involving patients and caregivers in research in CKD and in health research more broadly. These frameworks provide an overall conceptual structure to guide the planning and implementation of research partnerships and describe values that are essential and strategies considered best practice when working with diverse stakeholder groups. This article aims to provide a summary of the strategies most widely used to support multistakeholder partnerships, the different ways patients and caregivers can be involved in research and the methods used to amalgamate diverse and at times conflicting points of view.

Characteristics of Kidney Transplant Recipients with Prolonged Pre-Transplant Dialysis Duration as Identified by Machine Learning Consensus Clustering: Pathway to Personalized Care

Longer pre-transplant dialysis duration is known to be associated with worse post-transplant outcomes. Our study aimed to cluster kidney transplant recipients with prolonged dialysis duration before transplant using an unsupervised machine learning approach to better assess heterogeneity within this cohort. We performed consensus cluster analysis based on recipient-, donor-, and transplant-related characteristics in 5092 kidney transplant recipients who had been on dialysis ≥ 10 years prior to transplant in the OPTN/UNOS database from 2010 to 2019. We characterized each assigned cluster and compared the posttransplant outcomes. Overall, the majority of patients with ≥10 years of dialysis duration were black (52%) or Hispanic (25%), with only a small number (17.6%) being moderately sensitized. Within this cohort, three clinically distinct clusters were identified. Cluster 1 patients were younger, non-diabetic and non-sensitized, had a lower body mass index (BMI) and received a kidney transplant from younger donors. Cluster 2 recipients were older, unsensitized and had a higher BMI; they received kidney transplant from older donors. Cluster 3 recipients were more likely to be female with a higher PRA. Compared to cluster 1, cluster 2 had lower 5-year death-censored graft (HR 1.40; 95% CI 1.16-1.71) and patient survival (HR 2.98; 95% CI 2.43-3.68). Clusters 1 and 3 had comparable death-censored graft and patient survival. Unsupervised machine learning was used to characterize kidney transplant recipients with prolonged pre-transplant dialysis into three clinically distinct clusters with variable but good post-transplant outcomes. Despite a dialysis duration ≥ 10 years, excellent outcomes were observed in most recipients, including those with moderate sensitization. A disproportionate number of minority recipients were observed within this cohort, suggesting multifactorial delays in accessing kidney transplantation.

Clinical and Genetic Characteristics of CKD Patients with High-Risk APOL1 Genotypes

SIGNIFICANCE STATEMENT

APOL1 high-risk genotypes confer a significant risk of kidney disease, but variability in patient outcomes suggests the presence of modifiers of the APOL1 effect. We show that a diverse population of CKD patients with high-risk APOL1 genotypes have an increased lifetime risk of kidney failure and higher eGFR decline rates, with a graded risk among specific high-risk genotypes. CKD patients with high-risk APOL1 genotypes have a lower diagnostic yield for monogenic kidney disease. Exome sequencing revealed enrichment of rare missense variants within the inflammasome pathway modifying the effect of APOL1 risk genotypes, which may explain some clinical heterogeneity.

BACKGROUND

APOL1 genotype has significant effects on kidney disease development and progression that vary among specific causes of kidney disease, suggesting the presence of effect modifiers.

METHODS

We assessed the risk of kidney failure and the eGFR decline rate in patients with CKD carrying high-risk ( N =239) and genetically matched low-risk ( N =1187) APOL1 genotypes. Exome sequencing revealed monogenic kidney diseases. Exome-wide association studies and gene-based and gene set-based collapsing analyses evaluated genetic modifiers of the effect of APOL1 genotype on CKD.

RESULTS

Compared with genetic ancestry-matched patients with CKD with low-risk APOL1 genotypes, those with high-risk APOL1 genotypes had a higher risk of kidney failure (Hazard Ratio [HR]=1.58), a higher decline in eGFR (6.55 versus 3.63 ml/min/1.73 m 2 /yr), and were younger at time of kidney failure (45.1 versus 53.6 years), with the G1/G1 genotype demonstrating the highest risk. The rate for monogenic kidney disorders was lower among patients with CKD with high-risk APOL1 genotypes (2.5%) compared with those with low-risk genotypes (6.7%). Gene set analysis identified an enrichment of rare missense variants in the inflammasome pathway in individuals with high-risk APOL1 genotypes and CKD (odds ratio=1.90).

CONCLUSIONS

In this genetically matched cohort, high-risk APOL1 genotypes were associated with an increased risk of kidney failure and eGFR decline rate, with a graded risk between specific high-risk genotypes and a lower rate of monogenic kidney disease. Rare missense variants in the inflammasome pathway may act as genetic modifiers of APOL1 effect on kidney disease.

The association between fasting plasma glucose variability and incident eGFR decline: evidence from two cohort studies

BACKGROUND

Glycemic variability (GV) is developing as a marker of glycemic control, which can be utilized as a promising predictor of complications. To determine whether long-term GV is associated with incident eGFR decline in two cohorts of Tehran Lipid and Glucose Study (TLGS) and Multi-Ethnic Study of Atherosclerosis (MESA) during a median follow-up of 12.2 years.

METHODS

Study participants included 4422 Iranian adults (including 528 patients with T2D) aged ≥ 20 years from TLGS and 4290 American adults (including 521 patients with T2D) aged ≥ 45 years from MESA. The Multivariate Cox proportional hazard models were used to assess the risk of incident eGFR decline for each of the fasting plasma glucose (FPG) variability measures including standard deviation (SD), coefficient of variation (CV), average real variability (ARV), and variability independent of the mean (VIM) both as continuous and categorical variables. The time of start for eGFR decline and FPG variability assessment was the same, but the event cases were excluded during the exposure period.

RESULTS

In TLGS participants without T2D, for each unit change in FPG variability measures, the hazards (HRs) and 95% confidence intervals (CI) for eGFR decline ≥ 40% of SD, CV, and VIM were 1.07(1.01-1.13), 1.06(1.01-1.11), and 1.07(1.01-1.13), respectively. Moreover, the third tertile of FPG-SD and FPG-VIM parameters was significantly associated with a 60 and 69% higher risk for eGFR decline ≥ 40%, respectively. In MESA participants with T2D, each unit change in FPG variability measures was significantly associated with a higher risk for eGFR decline ≥ 40%.Regarding eGFR decline ≥ 30% as the outcome, in the TLGS, regardless of diabetes status, no association was shown between FPG variability measures and risk of eGFR decline in any of the models; however, in the MESA the results were in line with those of GFR decline ≥ 40%.Using pooled data from the two cohorts we found that generally FPG variability were associated with higher risk of eGFR decline ≥ 40% only among non-T2D individuals.

CONCLUSIONS

Higher FPG variability was associated with an increased risk of eGFR decline in the diabetic American population; however, this unfavorable impact was found only among the non-diabetic Iranian population.

Research Priorities for Interventions to Address Health Disparities in Lung Nodule Management: An Official American Thoracic Society Research Statement

Background: Lung nodules are common incidental findings, and timely evaluation is critical to ensure diagnosis of localized-stage and potentially curable lung cancers. Rates of guideline-concordant lung nodule evaluation are low, and the risk of delayed evaluation is higher for minoritized groups. Objectives: To summarize the existing evidence, identify knowledge gaps, and prioritize research questions related to interventions to reduce disparities in lung nodule evaluation. Methods: A multidisciplinary committee was convened to review the evidence and identify key knowledge gaps in four domains: 1) research methodology, 2) patient-level interventions, 3) clinician-level interventions, and 4) health system-level interventions. A modified Delphi approach was used to identify research priorities. Results: Key knowledge gaps included 1) a lack of standardized approaches to identify factors associated with lung nodule management disparities, 2) limited data evaluating the role of social determinants of health on disparities in lung nodule management, 3) a lack of certainty regarding the optimal strategy to improve patient-clinician communication and information transmission and/or retention, and 4) a paucity of information on the impact of patient navigators and culturally trained multidisciplinary teams. Conclusions: This statement outlines a research agenda intended to stimulate high-impact studies of interventions to mitigate disparities in lung nodule evaluation. Research questions were prioritized around the following domains: 1) need for methodologic guidelines for conducting research related to disparities in nodule management, 2) evaluating how social determinants of health influence lung nodule evaluation, 3) studying approaches to improve patient-clinician communication, and 4) evaluating the utility of patient navigators and culturally enriched multidisciplinary teams to reduce disparities.

Medicare Advantage Enrollment Among Beneficiaries With End-Stage Renal Disease in the First Year of the 21st Century Cures Act

Importance

Before 2021, most Medicare beneficiaries with end-stage renal disease (ESRD) were unable to enroll in private Medicare Advantage (MA) plans. The 21st Century Cures Act permitted these beneficiaries to enroll in MA plans effective January 2021.

Objective

To examine changes in MA enrollment among Medicare beneficiaries with ESRD after enactment of the 21st Century Cures Act overall and by race or ethnicity and dual-eligible status.

Design, Setting, and Participants

This cross-sectional time-trend study used data from Medicare beneficiaries with ESRD (both kidney transplant recipients and those undergoing dialysis) between January 2019 and December 2021. Data were analyzed between June and October 2022.

Exposures

21st Century Cures Act.

Main Outcomes and Measures

Primary outcomes were the proportion of Medicare beneficiaries with prevalent ESRD who switched from traditional Medicare to MA between 2020 and 2021 and those with incident ESRD who newly enrolled in MA in 2021. Individuals who stayed in traditional Medicare were enrolled in 2020 and 2021 and those who switched to MA were enrolled in traditional Medicare in 2020 and MA in 2021.

Results

Among 575 797 beneficiaries with ESRD in 2020 or 2021 (mean [SD] age, 64.7 [14.2] years, 42.2% female, 34.0% Black, and 7.7% Hispanic or Latino), the proportion of beneficiaries enrolled in MA increased from 24.8% (December 2020) to 37.4% (December 2021), a relative change of 50.8%. The largest relative increases in MA enrollment were among Black (72.8% relative increase), Hispanic (44.8%), and dual-eligible beneficiaries with ESRD (73.6%). Among 359 617 beneficiaries with TM and prevalent ESRD in 2020, 17.6% switched to MA in 2021. Compared with individuals who stayed in traditional Medicare, those who switched to MA had modestly more chronic conditions (6.3 vs 6.1; difference, 0.12 conditions [95% CI, 0.10-0.16]) and similar nondrug spending in 2020 (difference, $509 [95% CI, -$58 to $1075]) but were more likely to be Black (difference, 19.5 percentage points [95% CI, 19.1-19.9]) and have dual Medicare-Medicaid eligibility (difference, 20.8 percentage points [95% CI, 20.4-21.2]). Among beneficiaries who were newly eligible for Medicare ESRD benefits in 2021, 35.2% enrolled in MA.

Conclusions and Relevance

Results suggest that increases in MA enrollment among Medicare beneficiaries with ESRD were substantial the first year after the 21st Century Cures Act, particularly among Black, Hispanic, and dual-eligible individuals. Policy makers and MA plans may need to assess network adequacy, disenrollment, and equity of care for beneficiaries who enrolled in MA.

The ASCENT Intervention to Improve Access and Reduce Racial Inequalities in Kidney Waitlisting: A Randomized, Effectiveness-Implementation Trial

BACKGROUND

The US kidney allocation system (KAS) changed in 2014, but dialysis facility staff (including nephrologists, social workers, nurse managers, and facility administrators) had low awareness of how this policy change could affect their patients' access to transplant. We assessed the effectiveness of a multicomponent and multilevel educational and outreach intervention targeting US dialysis facilities with low waitlisting, with a goal of increasing waitlisting and reducing Black versus White racial disparities in waitlisting.

METHODS

The Allocation System Changes for Equity in Kidney Transplantation (ASCENT) study was a cluster-randomized, pragmatic, multilevel, effectiveness-implementation trial including 655 US dialysis facilities with low waitlisting, randomized to receive either the ASCENT intervention (a performance feedback report, a webinar, and staff and patient educational videos) or an educational brochure. Absolute and relative differences in coprimary outcomes (1-year waitlisting and racial differences in waitlisting) were reported among incident and prevalent patients.

RESULTS

Among 56,332 prevalent patients, 1-year waitlisting decreased for patients in control facilities (2.72%-2.56%) and remained the same for patients in intervention facilities (2.68%-2.75%). However, the proportion of prevalent Black patients waitlisted in the ASCENT interventions increased from baseline to 1 year (2.52%-2.78%), whereas it remained the same for White patients in the ASCENT intervention facilities (2.66%-2.69%). Among incident patients in ASCENT facilities, 1-year waitlisting increased among Black patients (from 0.87% to 1.07%) but declined among White patients (from 1.54% to 1.27%). Significant racial disparities in waitlisting were observed at baseline, with incident Black patients in ASCENT facilities less likely to waitlist compared with White patients (adjusted odds ratio [aOR], 0.56; 95% confidence interval [CI], 0.35 to 0.92), but 1 year after the intervention, this racial disparity was attenuated (aOR, 0.84; 95% CI, 0.49 to 1.42).

CONCLUSIONS

The ASCENT intervention may have a small effect on extending the reach of the new KAS policy by attenuating racial disparities in waitlisting among a population of US dialysis facilities with low waitlisting.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

National Institutes of Health ( NCT02879812 ).

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_03_08_CJN09760822.mp3.

United Network for Organ Sharing (UNOS) Database Analysis of Factors Associated With Kidney Transplant Time on Waiting List

INTRODUCTION

 In the United States (U.S.), African Americans and other minority groups have longer wait times for kidney transplantation than Caucasians. To date, many studies analyzing time spent on the waitlist for each race/ethnicity have been done. However, there are few to no studies examining waitlist time after the 2019 policy changes to the geographic distribution of donated kidneys.

METHODS

Data collected from the National Organ Procurement and Transplantation Network database were used to analyze associations between race and time spent on the waitlist for a kidney transplant in the U.S. Additional sub-categorical data were analyzed to determine further associations and potential covariates, such as gender, age, citizenship, primary source of payment, region of transplant center, BMI, Kidney Donor Profile Index (KDPI), renal diagnosis, and presence/type of diabetes. Data were analyzed using odds ratios and validated by Bonferroni-Holm's corrected chi-square tests at confidence intervals of 95% to determine if there are statistically significant differences between transplant time spent on the waitlist and ethnicity, as well as age, diagnosis category, region of transplant center, and KDPI.

RESULTS

Statistically significant increased odds of remaining on the transplant list at two years existed for all non-white races/ethnicities, except those identifying as multiracial. Asian American candidates had the greatest odds of remaining on the waitlist greater than two years in comparison to white candidates: 1.51 times that of a patient categorized as white (odds ratio [OR] 1.51, confidence interval [CI] 1.44-1.57). African American/Black, (OR 1.38, CI 1.34-1.43) Pacific Islander (OR 1.38, CI 1.17-1.63), Hispanic candidates (OR 1.37, CI 1.32-1.41), and American Indian or Native Alaskan candidates (OR 1.23, CI 1.12-1.46) also had increased odds of remaining on the transplant waitlist greater than two years compared to white candidates.

DISCUSSION

In this study, ethnic disparities persisted as a barrier for non-white individuals receiving treatment for end-stage kidney disease, specifically in the context of time spent on the waitlist for a kidney transplant. Further research is needed regarding the causes of these disparities in time spent on the waitlist, such as cultural restrictions in organ donation, racial differences in parameters for organ match, and institutionalized racism in health care practitioners.

Broad organ acceptance and equitable access to early kidney transplantation

BACKGROUND

Broad organ acceptance can increase early kidney transplantation (KTX) within <1-year of dialysis initiation while improving access inequity.

METHODS

Single-center data of adult isolated deceased-donor KTX recipients between 2013 and 2020 were stratified into three 2.5-year periods before-, early after-, and late after our center's deceased-donor organ acceptance practice change, excluding a 6-month implementation period. Outcomes were assessed within five recipient subgroups based on demographic and clinical characteristics.

RESULTS

Of 704 recipients, the frequency of early KTX was 22% pre-change, 36% early post-change, and 34% late post-change. Given similar post-change frequencies of early KTX, post-change eras were combined to improve analytic power of subgroup analyses. After the organ acceptance practice change (vs. pre-change), the likelihood of early KTX increased variably within historically underserved groups, including recipients who were older (37%-39%, p = .859), Black (10%-21%, p = .136), female (21%-37%, p = .034), diabetic (13%-32%, p = .010), and BMI≥35 kg/m² (20%-34%, p = .007). Despite the practice change, Black recipients continued to experience less early KTX compared to non-Black recipients. The likelihood of delayed graft function was significantly increased (p < .001), and 1-year creatinine was significantly higher (p < .001) post-practice change, but between-era risk-adjusted death-censored graft survival was similar.

CONCLUSIONS

Transition to broader donor acceptance was associated with more early KTXs among historically underserved patient subgroups. However, the effect was non-significant among Black recipients, suggesting the need for additional strategies to impact early transplant access for this population. Studies of broad organ acceptance are needed to examine both access and outcomes.

Perception of social inequities in the access to the kidney transplant waiting list by nephrology trainees: a national survey

BACKGROUND

Social inequalities in health are responsible for disparities in access to the kidney transplant waiting list (KTWL). The perception of disparities by nephrologists has consequences for the registration on the KTWL. The purposes of our study were to assess the perception of the factors implicated in the disparities in access to the KTWL by nephrology trainees and to assess the quality of the questionnaire.

METHODS

A questionnaire was developed to assess the perception of the determinants of the inequities in access to waitlisting. Continuous variables were described by median, 1st and 3rd quartiles. Categorical variables were described by frequencies and percentages. A principal component analysis and a hierarchical cluster analysis were performed to approach the correlation between the variables. A scree plot and a factor analysis were performed to determine the dimensions of the questionnaire. The internal consistency was estimated by Cronbach's coefficient.

RESULTS

The response rate was 98/110 (89%). The determinants of inequities in the access to KTWL not perceived by the nephrology trainees were "female sex", "income level" and "the centre provision to adapt the information to all of the patients" (18,3%, 36,7, 47% respectively). "Age", "being born abroad", "place of living", "education level", "transplant centre", "the health care provider" were determinants of disparities perceived by most of the trainees (85,7%, 75,5%, 82,6%, 78,6%, 73,5% et 78,5% respectively). Items related to the transplant centre were positively correlated, as well as "being born abroad", "education level" and "income level". The Cronbach's coefficient was 0,60.

CONCLUSION

Social inequalities in health are partially perceived by nephrology trainees. A teaching session could raise nephrologists' awareness of this issue and could help reduce the impact of these disparities on the course of ESKD (end-stage kidney disease) patients.

Referral and Evaluation for Kidney Transplantation Following Implementation of the 2014 National Kidney Allocation System

RATIONALE & OBJECTIVE

The national kidney allocation system (KAS) implemented in December 2014 in the United States redefined the start of waiting time from the time of waitlisting to the time of kidney failure. Waitlisting has declined post-KAS, but it is unknown if this is due to transplant center practices or changes in dialysis facility referral and evaluation. The purpose of this study was to assess the impact of the 2014 KAS policy change on referral and evaluation for transplantation among a population of incident and prevalent patients with kidney failure.

STUDY DESIGN

Cohort study.

SETTING & PARTICIPANTS

37,676 incident (2012-2016) patients in Georgia, North Carolina, and South Carolina identified within the US Renal Data System at 9 transplant centers and followed through December 2017. A prevalent population of 6,079 patients from the same centers receiving maintenance dialysis in 2012 but not referred for transplantation in 2012.

EXPOSURE

KAS era (pre-KAS vs post-KAS).

OUTCOME

Referral for transplantation, start of transplant evaluation, and waitlisting.

ANALYTICAL APPROACH

Multivariable time-dependent Cox models for the incident and prevalent population.

RESULTS

Among incident patients, KAS was associated with increased referrals (adjusted HR, 1.16 [95% CI, 1.12-1.20]) and evaluation starts among those referred (adjusted HR, 1.16 [95% CI, 1.10-1.21]), decreased overall waitlisting (adjusted HR, 0.70 [95% CI, 0.65-0.76]), and lower rates of active waitlisting among those evaluated compared to the pre-KAS era (adjusted HR, 0.81 [95% CI, 0.74-0.90]). Among the prevalent population, KAS was associated with increases in overall waitlisting (adjusted HR, 1.74 [95% CI, 1.15-2.63]) and active waitlisting among those evaluated (adjusted HR, 2.01 [95% CI, 1.16-3.49]), but had no significant impact on referral or evaluation starts among those referred.

LIMITATIONS

Limited to 3 states, residual confounding.

CONCLUSIONS

In the southeastern United States, the impact of KAS on steps to transplantation was different among incident and prevalent patients with kidney failure. Dialysis facilities referred more incident patients and transplant centers evaluated more incident patients after implementation of KAS, but fewer evaluated patients were placed onto the waitlist. Changes in dialysis facility and transplant center behaviors after KAS implementation may have influenced the observed changes in access to transplantation.

Medicaid Expansion and Medicare-Financed Hospitalizations Among Adult Patients With Incident Kidney Failure

Importance

Although Medicare provides health insurance coverage for most patients with kidney failure in the US, Medicare beneficiaries who initiate dialysis without supplemental coverage are exposed to substantial out-of-pocket costs. The availability of expanded Medicaid coverage under the Patient Protection and Affordable Care Act (ACA) for adults with kidney failure may improve access to care and reduce Medicare-financed hospitalizations after dialysis initiation.

Objective

To examine the implications of the ACA's Medicaid expansion for Medicare-financed hospitalizations, health insurance coverage, and predialysis nephrology care among Medicare-covered adults aged 19 to 64 years with incident kidney failure in the first year after initiating dialysis.

Design, Setting, and Participants

This cross-sectional study used a difference-in-differences approach to assess Medicare-financed hospitalizations among adults aged 19 to 64 years who initiated dialysis between January 1, 2010, and December 31, 2018, while covered by Medicare Part A (up to 5 years postexpansion). Data on patients were obtained from the Renal Management Information System's End Stage Renal Disease Medical Evidence Report, which includes data for all patients initiating outpatient maintenance dialysis regardless of health insurance coverage, treatment modality, or citizenship status, and these data were linked with claims data from the Medicare Provider Analysis and Review. Data were analyzed from January to August 2022.

Exposure

Living in a Medicaid expansion state.

Main Outcomes and Measures

Primary outcomes were number of Medicare-financed hospitalizations and hospital days in the first 3 months, 6 months, and 12 months after dialysis initiation. Secondary outcomes included dual Medicare and Medicaid coverage at 91 days after dialysis initiation and the presence of an arteriovenous fistula or graft at dialysis initiation for patients undergoing hemodialysis.

Results

The study population included 188 671 adults, with 97 071 living in Medicaid expansion states (mean [SD] age, 53.4 [9.4] years; 58 329 men [60.1%]) and 91 600 living in nonexpansion states (mean [SD] age, 53.0 [9.6] years; 52 677 men [57.5%]). In the first 3 months after dialysis initiation, Medicaid expansion was associated with a significant decrease in Medicare-financed hospitalizations (-4.24 [95% CI, -6.70 to -1.78] admissions per 100 patient-years; P = .001) and hospital days (-0.73 [95% CI, -1.08 to -0.39] days per patient-year; P < .001), relative reductions of 8% for both outcomes. Medicaid expansion was associated with a 2.58-percentage point (95% CI, 0.88-4.28 percentage points; P = .004) increase in dual Medicare and Medicaid coverage at 91 days after dialysis initiation and a 1.65-percentage point (95% CI, 0.31-3.00 percentage points; P = .02) increase in arteriovenous fistula or graft at initiation.

Conclusions and Relevance

In this cross-sectional study with a difference-in-differences analysis, the ACA's Medicaid expansion was associated with decreases in Medicare-financed hospitalizations and hospital days and increases in dual Medicare and Medicaid coverage. These findings suggest favorable spillover outcomes of Medicaid expansion to Medicare-financed care, which is the primary payer for patients with kidney failure.

Patient Navigators for CKD and Kidney Failure: A Systematic Review

Rationale & Objective

To what degree and how patient navigators improve clinical outcomes for patients with chronic kidney disease (CKD) and kidney failure is uncertain. We performed a systematic review to summarize patient navigator program design, evidence, and implementation in kidney disease.

Study Design

A search strategy was developed for randomized controlled trials and observational studies that evaluated the impact of navigators on outcomes in the setting of CKD and kidney failure. Articles were identified from various databases. Two reviewers independently screened the articles and identified those meeting the inclusion criteria.

Setting & Participants

Patients with CKD or kidney failure (in-center hemodialysis, peritoneal dialysis, home hemodialysis, or kidney transplantation).

Selection Criteria for Studies

Studies that compared patient navigators with a control, without limits on size, duration, setting, or language. Studies focusing solely on patient education were excluded.

Data Extraction

Data were abstracted from full texts and risk of bias was assessed.

Analytical Approach

No meta-analysis was performed.

Results

Of 3,371 citations, 17 articles met the inclusion criteria including 14 original studies. Navigators came from various healthcare backgrounds including nursing (n=6), social worker (n=2), medical interpreter (n=1), research (n=1), and also included kidney transplant recipients (n=2) and non-medical individuals (n=2). Navigators focused mostly on education (n=9) and support (n = 6). Navigators were used for patients with CKD (n=5), peritoneal dialysis (n=2), in-center hemodialysis (n=4), kidney transplantation (n=2), but not home hemodialysis. Navigators improved transplant workup and listing, peritoneal dialysis utilization, and patient knowledge.

Limitations

Many studies did not show benefits across other outcomes, were at a high risk of bias, and none reported cost-effectiveness or patient-reported experience measures.

Conclusions

Navigators improve some health outcomes for CKD but there was heterogeneity in their structure and function. High-quality randomized controlled trials are needed to evaluate navigator program efficacy and cost-effectiveness.

The Role of Social Risk Factors in Dialysis Quality and Patient Outcomes Under a Medicare Quality Incentive Program

BACKGROUND

There have been critical improvements in dialysis care and mortality in the last decade. These improvements track with the implementation of the end-stage renal disease (ESRD) Quality Incentive Program (QIP) beginning in 2012, which aligns Medicare payments to dialysis facilities with performance on quality measures. This study explores whether the improvements in dialysis care and patient outcomes under the ESRD QIP have been shared equally among patient groups.

METHODS

Our analyses focus on 4 social risk factors: Black race, Hispanic ethnicity, dual eligibility for Medicare and Medicaid, and rurality. We estimated multivariable regressions using longitudinal Medicare and Consolidated Renal Operations in a Web-Enabled Network data.

RESULTS

ESRD QIP payment reductions were more common at dialysis facilities with higher proportions of Black and dual-eligible ESRD patients. Patients with dual eligibility and Black race had persistently worse relative outcomes as the ESRD QIP was implemented. This finding was true for differences in outcomes when comparing patients within and across facilities and was not affected by the addition of specific quality measures to the ESRD QIP measure set. Hispanic patients and patients at rural facilities have generally not had worse outcomes since the start of the ESRD QIP.

CONCLUSIONS

There is no evidence of widening disparities in dialysis care or patient outcomes across patient groups under the ESRD QIP, which is a longstanding and well-publicized concern with value-based purchasing programs. Relative changes between patient groups since the start of ESRD QIP have not favored any patient group. Many disparities in dialysis quality measures and assessment of dialysis facility payment reductions persist.

Geospatial Analysis of Organ Transplant Referral Regions

IMPORTANCE

System and center-level interventions to improve health equity in organ transplantation benefit from robust characterization of the referral population served by each transplant center. Transplant referral regions (TRRs) define geographic catchment areas for transplant centers in the US, but accurately characterizing the demographics of populations within TRRs using US Census data poses a challenge.

OBJECTIVE

To compare 2 methods of linking US Census data with TRRs-a geospatial intersection method and a zip code cross-reference method.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study compared spatial congruence of spatial intersection and zip code cross-reference methods of characterizing TRRs at the census block level. Data included adults aged 18 years and older on the waiting list for kidney transplant from 2008 through 2018.

EXPOSURES

End-stage kidney disease.

MAIN OUTCOMES AND MEASURES

Multiple assignments, where a census tract or block group crossed the boundary between 2 hospital referral regions and was assigned to multiple different TRRs; misassigned area, the portion of census tracts or block groups assigned to a TRR using either method but fall outside of the TRR boundary.

RESULTS

In total, 102 TRRs were defined for 238 transplant centers. The zip code cross-reference method resulted in 4627 multiple-assigned census block groups (representing 18% of US land area assigned to TRRs), while the spatial intersection method eliminated this problem. Furthermore, the spatial method resulted in a mean and median reduction in misassigned area of 65% and 83% across all TRRs, respectively, compared with the zip code cross-reference method.

CONCLUSIONS AND RELEVANCE

In this study, characterizing populations within TRRs with census block groups provided high spatial resolution, complete coverage of the country, and balanced population counts. A spatial intersection approach avoided errors due to duplicative and incorrect assignments, and allowed more detailed and accurate characterization of the sociodemographics of populations within TRRs; this approach can enrich transplant center knowledge of local referral populations, assist researchers in understanding how social determinants of health may factor into access to transplant, and inform interventions to improve heath equity.

A Population Health Approach to Transplant Access: Challenging the Status Quo

Transplant referral and evaluation are critical steps to waitlisting yet remain an elusive part of the transplant process. Despite calls for more data collection on pre-waitlisting steps, there are currently no national surveillance data to aid in understanding the causes and potential solutions for the extreme variation in access to transplantation. As population health scientists, epidemiologists, clinicians, and ethicists we submit that the transplant community has an obligation to better understand disparities in transplant access as a first necessary step to effectively mitigating these inequities. Our position is grounded in a population health approach, consistent with several new overarching national policy and quality initiatives. The purpose of this Perspective is to (1) provide an overview of how a population health approach should inform current multisystem policies impacting kidney transplantation and demonstrate how these efforts could be enhanced with national data collection on pre-waitlisting steps; (2) demonstrate the feasibility and concrete next steps for pre-waitlisting data collection; and (3) identify potential opportunities to use these data to implement effective population-level interventions, policies, and quality measures to improve equity in access to kidney transplantation.

Changes in the spectrum of kidney diseases: a survey of 2803 patients from 2010 to 2018 at a single center in southeastern China

Primary glomerular disease was the leading cause of chronic kidney disease (CKD) in China; however, changes in the economy and environment introduce variations in the spectrum of kidney diseases. This study aimed to analyze renal biopsy data to inform disease prevention and public health interventions. In this retrospective cohort study, data from 2,803 consecutive renal biopsies conducted at our center between January 2010 and December 2018 were analyzed. The sample was disaggregated by age and the date of biopsy to facilitate analysis. Primary glomerulonephritis (PGN) is the most frequent (81.84%) finding, followed by secondary glomerulonephritis (SGN; 15.38%), tubulointerstitial nephritis (15.38%), and others (1.57%). IgA nephropathy (IgAN), idiopathic membranous nephropathy (iMN), and minimal change disease were the primary causes of PGN. Among PGN cases, the incidence of iMN arose, especially among those aged ≥ 60 years old, during the observation period. Contrary to the case of iMN, the proportion of IgAN in PGN trended downward, continuously, and at length. Moreover, IgAN mainly affected those aged 25–44 years old and less so those aged ≥ 60 years old. Lupus nephritis, Henoch–Schönlein purpura nephritis, and diabetic nephropathy (DN) were key causes of SGN. A ratio reversal between infectious disease and chronic disease dramatically changed SGN patterns. In the past year, the incidence of hepatitis B–related nephritis has constantly declined; however, the proportion of DN among SGN had steadily increased. The incidence of iMN significantly increased during these years. Among SGN cases, the proportion of DN has increased.

Black-White Inequities in Kidney Disease Mortality Across the 30 Most Populous US Cities

OBJECTIVES

To examine city-level kidney disease mortality rates and Black:White racial inequities for the USA and its largest cities, and to determine if these measures changed over the past decade.

METHODS

We used National Vital Statistics System mortality data and American Community Survey population estimates to calculate age-standardized kidney disease mortality rates for the non-Hispanic Black (Black), non-Hispanic White (White), and total populations for the USA and the 30 most populous US cities. We examined two time points, 2008-2013 (T1) and 2014-2018 (T2), and assessed changes in rates and inequities over time. Racial inequities were measured with Black:White mortality rate ratios and rate differences.

RESULTS

Kidney disease mortality rates varied from 2.5 (per 100,000) in San Diego to 24.6 in Houston at T2. The Black kidney disease mortality rate was higher than the White rate in the USA and all cities studied at both time points. In T2, the Black mortality rate ranged from 7.9 in New York to 45.4 in Charlotte, while the White mortality rate ranged from 2.0 in San Diego to 18.6 in Indianapolis. At T2, the Black:White rate ratio ranged from 1.79 (95% CI 1.62-1.99) in Philadelphia to 5.25 (95% CI 3.40-8.10) in Washington, DC, compared to the US rate ratio of 2.28 (95% CI 2.25-2.30). Between T1 and T2, only one city (Nashville) saw a significant decrease in the Black:White mortality gap.

CONCLUSIONS

The largest US cities experience widely varying kidney disease mortality rates and widespread racial inequities. These local data on racial inequities in kidney disease mortality can be used by city leaders and health stakeholders to increase awareness, guide the allocation of limited resources, monitor trends over time, and support targeted population health strategies.

R. S, Toh CC, Sundram M, Md Yusoff NA, Nagappan P, Kamaruzaman S, Yeoh WS, Ong TA, Lim J. Cardiovascular risk factors, ethnicity and infection stone are independent factors associated with reduced renal function in renal stone formers

Background

Recent evidence suggested the link between nephrolithiasis and renal function impairment. We aimed to determine the renal function profile and potential factors associated with reduced renal function amongst renal stone formers in multi-ethnic Asians.

Methods

We conducted a cross-sectional study involving patients undergoing percutaneous nephrolithotomy between May 2015 and December 2019. Reduced renal function was defined as having estimated glomerular filtration rate < 60 ml/min per 1.73 m². Renal stone samples were collected and quantified using infrared spectroscopy. Potential factors associated with reduced renal function including age, ethnicity, educational level, history of diabetes, hypertension, gout, hydronephrosis, serum uric acid level, and type of renal stone were evaluated using univariable and multivariable analyses.

Results

A total of 1162 patients from a multi-ethnic population (Malays 67%, Chinese 19%, Indians 13% and indigenous people 1%) with median age of 57 years (Interquartile range 48–64) were enrolled in the study. Almost a third of patients were found with reduced renal function. Multivariable analysis showed that the odds of having reduced renal function increased with age, ethnicity, lower educational level, history of diabetes, hypertension, gout, bilateral hydronephrosis, elevated serum uric acid level and infection stone.

Conclusions

Reduced renal function varies between ethnicities and all age groups of renal stone formers. In addition to age and ethnicity, cardiovascular risk factors including diabetes and hypertension may also need to be taken into account in managing stone patients with reduced renal function.

Modeling Chronic Kidney Disease in Type 2 Diabetes Mellitus: A Systematic Literature Review of Models, Data Sources, and Derivation Cohorts

INTRODUCTION

As novel therapies for chronic kidney disease (CKD) in type 2 diabetes mellitus (T2DM) become available, their long-term benefits should be evaluated using CKD progression models. Existing models offer different modeling approaches that could be reused, but it may be challenging for modelers to assess commonalities and differences between the many available models. Additionally, the data and underlying population characteristics informing model parameters may not always be evident. Therefore, this study reviewed and summarized existing modeling approaches and data sources for CKD in T2DM, as a reference for future model development.

METHODS

This systematic literature review included computer simulation models of CKD in T2DM populations. Searches were implemented in PubMed (including MEDLINE), Embase, and the Cochrane Library, up to October 2021. Models were classified as cohort state-transition models (cSTM) or individual patient simulation (IPS) models. Information was extracted on modeled kidney disease states, risk equations for CKD, data sources, and baseline characteristics of derivation cohorts in primary data sources.

RESULTS

The review identified 49 models (21 IPS, 28 cSTM). A five-state structure was standard among state-transition models, comprising one kidney disease-free state, three kidney disease states [frequently including albuminuria and end-stage kidney disease (ESKD)], and one death state. Five models captured CKD regression and three included cardiovascular disease (CVD). Risk equations most commonly predicted albuminuria and ESKD incidence, while the most predicted CKD sequelae were mortality and CVD. Most data sources were well-established registries, cohort studies, and clinical trials often initiated decades ago in predominantly White populations in high-income countries. Some recent models were developed from country-specific data, particularly for Asian countries, or from clinical outcomes trials.

CONCLUSION

Modeling CKD in T2DM is an active research area, with a trend towards IPS models developed from non-Western data and single data sources, primarily recent outcomes trials of novel renoprotective treatments.

Gender Disparities in Kidney Transplantation Referral Vary by Age and Race – A Multi-Regional Cohort Study in the Southeast US

Introduction

Methods

Results

Conclusion

Understanding disparities and barriers associated with pediatric transplant evaluation and time to listing: Moving toward a more comprehensive picture

BACKGROUND

Delayed time to listing (TTL) for pediatric transplant patients is associated with increased risks of mortality and morbidity. The full range of health disparities, sociodemographic factors, and other barriers associated with delays in listing in the pediatric transplant candidate evaluation process has not been fully examined.

METHODS

Retrospective chart reviews were conducted for 183 kidney, liver, and heart transplant candidates ages 0-18 who were referred for evaluation during 2012-2015. Demographic information and potential barriers (e g., social/medical factors, financial concerns) were gathered from pre-transplant evaluations and included in a comprehensive model to evaluate mechanisms that explain differences in TTL. Descriptive statistics, logistic regression models, Cox proportional hazards models, and path analysis were used for analyses.

RESULTS

Candidates included 26.8% heart, 33.3% liver, and 39.9% kidney patients. The most common barrier to listing was financial (71.6%), followed by caregiver psychological or substance use (57.9%), and medical problems (49.7%). Higher age, kidney, and liver organ type (relative to the heart), and presence of social, medical, administrative/motivation, and financial barriers were all directly associated with longer TTL. Public insurance was indirectly associated with TTL through social, administrative/motivation, and financial barriers. Organ type was indirectly associated with TTL through financial barriers.

CONCLUSIONS

Results suggest social problems, administrative issues, and financial issues act as mechanisms through which insurance type and liver transplant candidates face increased risk of delays in transplant listing time. There are numerous clinical implications and interventions that are warranted to reduce TTL among pediatric transplant candidates with co-occurring barriers.

Initial Home Dialysis Is Increased for Rural Patients by Accessing Urban Facilities

Background

The 240,000 rural patients with end stage kidney disease in the United States have less access to nephrology care and higher mortality than those in urban settings. The Advancing American Kidney Health initiative aims to increase the use of home renal replacement therapy. Little is known about how rural patients access home dialysis and the availability and quality of rural dialysis facilities.

Methods

Incident dialysis patients in 2017 and their facilities were identified in the United States Renal Data System. Facility quality and service availability were analyzed with descriptive statistics. We assessed the availability of home dialysis methods, depending on rural versus urban counties, and then we used multivariate logistic regression to identify the likelihood of rural patients with home dialysis as their initial modality and the likelihood of rural patients changing to home dialysis within 90 days. Finally, we assessed mortality after dialysis initiation on the basis of patient home location.

Results

Of the 97,930 dialysis initiates, 15,310 (16%) were rural. Rural dialysis facilities were less likely to offer home dialysis (51% versus 54%, P<0.001). Although a greater proportion of rural patients (9% versus 8%, P<0.001) were on home dialysis, this was achieved by traveling to urban facilities to obtain home dialysis (OR=2.74, P<0.001). After adjusting for patient and facility factors, rural patients had a higher risk of mortality (HR=1.06, P=0.004).

Conclusions

Despite having fewer facilities that offer home dialysis, rural patients were more often on home dialysis methods because they traveled to urban facilities, representing an access gap. Even if rural patients accessed home dialysis at urban facilities, rural patients still suffered worse mortality. Future dialysis policy should address this access gap to improve care and overall mortality for rural patients.

Resolving the Debate: The Future of Using Race in Estimating Kidney Function

Racial and social unrest witnessed during 2020 ignited a national conversation about the appropriateness of the use of race in health care algorithms and in the estimation of kidney function in particular. The growing concerns over the use of race in kidney function-estimating equations prompted the National Kidney Foundation (NKF) and American Society of Nephrology to launch an effort for change by establishing a task force on reassessing the use of race in diagnosing kidney disease. After nearly a year examining the evidence and obtaining testimony from experts and stakeholders, the task force recommended the immediate implementation of the 2020 Chronic Kidney Disease-Epidemiology creatinine equation refit without race in all US laboratories; increased routine use of cystatin C for confirmation of estimated glomerular filtration rate in clinical decision-making and a call for research on glomerular filtration rate estimation with new endogenous filtration markers and on addressing disparities in health and health care. The NKF and American Society of Nephrology strongly encouraged rapid adoption of these new recommendations. Leadership efforts of the NKF have begun to lay the foundation for national implementation through laboratory engagement, clinician awareness, and patient education.

Despite National Declines In Kidney Failure Incidence, Disparities Widened Between Low- And High-Poverty US Counties

National estimates suggest that kidney failure incidence is declining in the US. However, whether this trend is evident in areas with socioeconomic disadvantage is unknown. We examined trends in kidney failure incidence by county-level poverty between 2000 and 2017 and divided the study period into period 1 (2000-05), period 2 (2006-11), and period 3 (2012-17). The magnitude of disparity in kidney failure incidence between high- and low-poverty counties increased from 42.8 more incident cases per million in high-poverty counties in period 1 to 100.1 more in period 3. Despite a national decline, kidney failure incidence increased in high-poverty counties, and disparities between high- and low-poverty counties widened from 2000 to 2017. Achieving the Department of Health and Human Services objective of reducing incident kidney failure cases by 25 percent by 2030 will require focused attention on preventing kidney failure in counties with higher poverty.

Racial and Ethnic Disparities in Hospital Admissions from COVID-19: Determining the Impact of Neighborhood Deprivation and Primary Language

BACKGROUND

Despite past and ongoing efforts to achieve health equity in the USA, racial and ethnic disparities persist and appear to be exacerbated by COVID-19.

OBJECTIVE

Evaluate neighborhood-level deprivation and English language proficiency effect on disproportionate outcomes seen in racial and ethnic minorities diagnosed with COVID-19.

DESIGN

Retrospective cohort study SETTING: Health records of 12 Midwest hospitals and 60 clinics in Minnesota between March 4, 2020, and August 19, 2020 PATIENTS: Polymerase chain reaction-positive COVID-19 patients EXPOSURES: Area Deprivation Index (ADI) and primary language MAIN MEASURES: The primary outcome was COVID-19 severity, using hospitalization within 45 days of diagnosis as a marker of severity. Logistic and competing-risk regression models assessed the effects of neighborhood-level deprivation (using the ADI) and primary language. Within race, effects of ADI and primary language were measured using logistic regression.

RESULTS

A total of 5577 individuals infected with SARS-CoV-2 were included; 866 (n = 15.5%) were hospitalized within 45 days of diagnosis. Hospitalized patients were older (60.9 vs. 40.4 years, p < 0.001) and more likely to be male (n = 425 [49.1%] vs. 2049 [43.5%], p = 0.002). Of those requiring hospitalization, 43.9% (n = 381), 19.9% (n = 172), 18.6% (n = 161), and 11.8% (n = 102) were White, Black, Asian, and Hispanic, respectively. Independent of ADI, minority race/ethnicity was associated with COVID-19 severity: Hispanic patients (OR 3.8, 95% CI 2.72-5.30), Asians (OR 2.39, 95% CI 1.74-3.29), and Blacks (OR 1.50, 95% CI 1.15-1.94). ADI was not associated with hospitalization. Non-English-speaking (OR 1.91, 95% CI 1.51-2.43) significantly increased odds of hospital admission across and within minority groups.

CONCLUSIONS

Minority populations have increased odds of severe COVID-19 independent of neighborhood deprivation, a commonly suspected driver of disparate outcomes. Non-English-speaking accounts for differences across and within minority populations. These results support the ongoing need to determine the mechanisms that contribute to disparities during COVID-19 while also highlighting the underappreciated role primary language plays in COVID-19 severity among minority groups.

Non-medical barriers in access to early steps of kidney transplantation in the United States - A scoping review

BACKGROUND

In the United States (US), barriers in access to later steps in the kidney transplantation process (i.e. waitlisting) have been well documented. Barriers in access to earlier steps (i.e. referral and evaluation) are less well described due to the lack of national surveillance data. In this review, we summarize the available literature on non-medical barriers in access to kidney transplant referral and evaluation.

METHODS

Following PRISMA guidelines, we conducted a scoping review of the literature through June 3, 2021. We included all studies (quantitative and qualitative) reporting on barriers to kidney transplant referral and evaluation in the US published from 1990 onwards in English and among adult end-stage kidney disease (ESKD) patients (PROSPERO registration number: CRD42014015027). We narratively synthesized results across studies.

RESULTS

We retrieved information from 33 studies published from 1990 to 2021 (reporting data between 1990 and 2018). Most studies (n = 28, 85%) described barriers among patient populations, three (9%) among provider populations, and two (6%) included both patients and providers. Key barriers were identified across multiple levels and included patient- (e.g. demographic, socioeconomic, sociocultural, and knowledge), provider- (e.g. miscommunication, staff availability, provider perceptions and attitudes), and system- (e.g. geography, distance to care, healthcare logistics) level factors.

CONCLUSIONS

A multi-pronged approach (e.g. targeted and systemwide interventions, and policy change) implemented at multiple levels of the healthcare system will be necessary to reduce identified barriers in access to early kidney transplant steps. Collection of national surveillance data on these early kidney transplant steps is also needed to enhance our understanding of barriers to referral and evaluation.

Nonmedical barriers to early steps in kidney transplantation among underrepresented groups in the United States

PURPOSE OF REVIEW

Despite numerous targeted interventions and policy reforms, underrepresented minorities and patients with low socioeconomic status (SES) continue to have unequal access to kidney transplant. In this review, we summarize the most recent evidence on barriers to early kidney transplant steps (i.e. referral and evaluation) among underrepresented racial and ethnic minorities and low SES groups in the United States.

RECENT FINDINGS

This review highlights the interconnectedness of several patient-level (e.g. medical mistrust, transplant knowledge, access to care), provider-level (e.g. dialysis profit status, patient--provider communication; staff accessibility), and system-level (e.g. center-specific criteria, healthcare logistics, neighborhood poverty, healthcare logistics) factors associated with lower rates of referral and evaluation among underrepresented minorities and low SES groups, and the influence of systemic racism operating at all levels.

SUMMARY

Collection of national surveillance data on early transplant steps, as well as routinely captured data on upstream social determinants of health, including the measurement of racism rather than race, is necessary to enhance our understanding of barriers to referral and evaluation. A multipronged approach (e.g. targeted and systemwide interventions, and policy change) implemented at multiple levels of the healthcare system will be necessary to reduce disparities in early transplant steps.

Excess Mortality Associated With COVID-19 by Demographic Group: Evidence From Florida and Ohio

OBJECTIVE

COVID-19 mortality varies across demographic groups at the national level, but little is known about potential differences in COVID-19 mortality across states. The objective of this study was to estimate the number of all-cause excess deaths associated with COVID-19 in Florida and Ohio overall and by sex, age, and race.

METHODS

We calculated the number of weekly and cumulative excess deaths among adults aged ≥20 from March 15 through December 5, 2020, in Florida and Ohio as the observed number of deaths less the expected number of deaths, adjusted for population, secular trends, and seasonality. We based our estimates on death certificate data from the previous 10 years.

RESULTS

The results were based on ratios of observed-to-expected deaths. The ratios were 1.17 (95% prediction interval, 1.14-1.21) in Florida and 1.15 (95% prediction interval, 1.11-1.19) in Ohio. Although the largest number of excess deaths occurred in the oldest age groups, in both states the ratios of observed-to-expected deaths were highest among adults aged 20-49 (1.21; 95% prediction interval, 1.11-1.32). The ratio of observed-to-expected deaths for the Black population was especially elevated in Florida.

CONCLUSIONS

Although excess deaths were largely concentrated among older cohorts, the high ratios of observed-to-expected deaths among younger age groups indicate widespread effects of COVID-19. The high levels of observed-to-expected deaths among Black adults may reflect in part disparities in infection rates, preexisting conditions, and access to care. The finding of high excess deaths among Black adults deserves further attention.

Prevalence of impaired renal function and determinants in the southwest of Iran

BACKGROUND

Chronic kidney disease (CKD) is a growing global health problem with faster progression in developing countries such as Iran. Here we aimed to evaluate the prevalence and determinants of CKD stage III+.

METHODS

This research is part of the Khuzestan Comprehensive Health Study (KCHS), a large observational population-based cross-sectional study in which 30,041 participants aged 20 to 65 were enrolled. CKD was determined with estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73m2, based on two equations of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI). The multivariate logistic regression was used to evaluate the CKD stage III+ determinants.

RESULTS

Prevalence of CKD stage III+ is estimated to be 7.1, 5.5, and 5.4% based on MDRD, CKD-EPI, and combination of both equations, respectively. More than 89% of CKD subjects aged higher than 40 years. In regression analysis, age more than 40 years had the strongest association with CKD stage III+ probability (OR: 8.23, 95% CI: 6.91-9.18). Higher wealth score, hypertension, High-Density Lipoprotein levels less than 40 mg/dl, and higher waist to hip ratio were all associated with CKD stage III+ while Arab ethnicity showed a protective effect (OR: 0.69, 95% CI: 0.57-0.78).

CONCLUSION

Our findings provide detailed information on the CKD stage III+ and its determinants in the southwest region of Iran. Due to strong association between age and CKD stage III+, within a few decades we might expect a huge rise in the CKD prevalence.

Policy in pediatric nephrology: successes, failures, and the impact on disparities

Pediatric nephrology has a history rooted in pediatric advocacy and has made numerous contributions to child health policy affecting pediatric kidney diseases. Despite this progress, profound social disparities remain for marginalized and socially vulnerable children with kidney disease. Different risk factors, such as genetic predisposition, environmental factors, social risk factors, or health care access influence the emergence and progression of pediatric kidney disease, as well as access to life-saving interventions, leading to disparate outcomes. This review will summarize the breadth of literature on social determinants of health in children with kidney disease worldwide and highlight policy-based initiatives that mitigate the adverse social factors to generate greater equity in pediatric kidney disease.

Reassessing the Inclusion of Race in Diagnosing Kidney Diseases: An Interim Report From the NKF-ASN Task Force

For almost 2 decades, equations that use serum creatinine, age, sex, and race to estimate glomerular filtration rate (GFR) have included "race" as Black or non-Black. Given considerable evidence of disparities in health and health care delivery in African American communities, some regard keeping a race term in GFR equations as a practice that differentially influences access to care and kidney transplantation. Others assert that race captures important non-GFR determinants of serum creatinine and its removal from the calculation may perpetuate other disparities. The National Kidney Foundation (NKF) and American Society of Nephrology (ASN) established a task force in 2020 to reassess the inclusion of race in the estimation of GFR in the United States and its implications for diagnosis and subsequent management of patients with, or at risk for, kidney diseases. This interim report details the process, initial assessment of evidence, and values defined regarding the use of race to estimate GFR. We organized activities in phases: (1) clarify the problem and examine evidence, (2) evaluate different approaches to address use of race in GFR estimation, and (3) make recommendations. In phase 1, we constructed statements about the evidence and defined values regarding equity and disparities; race and racism; GFR measurement, estimation, and equation performance; laboratory standardization; and patient perspectives. We also identified several approaches to estimate GFR and a set of attributes to evaluate these approaches. Building on evidence and values, the attributes of alternative approaches to estimate GFR will be evaluated in the next phases and recommendations will be made.

Effect of social deprivation on peritoneal dialysis uptake: A mediation analysis with the data of the REIN registry

BACKGROUND

Social deprivation could act as a barrier to peritoneal dialysis (PD). The objective of this study was to assess the association between social deprivation estimated by the European deprivation index (EDI) and PD uptake and to explore the potential mediators of this association.

METHODS

From the Renal Epidemiology and Information Network registry, patients who started dialysis in 2017 were included. The EDI was calculated based on the patient's address. The event of interest was the proportion of PD 3 months after dialysis initiation. A mediation analysis with a counterfactual approach was carried out to evaluate the direct and indirect effect of the EDI on the proportion of PD.

RESULTS

Among the 9588 patients included, 1116 patients were on PD; 2894 (30.2%) patients belonged to the most deprived quintile (Q5). PD was associated with age >70 years (odds ratio (OR) 0.79 [95% confidence interval (CI): 0.69-0.91]), male gender (0.85 [95% CI: 0.74-0.97]), cardiovascular disease (OR 0.86 [95% CI: 0.86-1.00]), chronic heart failure (OR 1.34 [95% CI: 1.13-1.58]), active cancer (OR 0.67 [95% CI: 0.53-0.85]) and obesity (OR 0.75 [95% CI: 0.63-0.89]). In the mediation analysis, Q5 had a direct effect on PD proportion OR 0.84 [95% CI: 0.73-0.96]. The effect of Q5 on the proportion of PD was mediated by haemoglobin level at dialysis initiation (OR 0.96 [95% CI: 0.94-0.98]) and emergency start (OR 0.98 [95% CI: 0.96-0.99]).

CONCLUSION

Social deprivation, estimated by the EDI, was associated with a lower PD uptake. The effect of social deprivation was mediated by haemoglobin level, a proxy of predialysis care and emergency start.