Racial disparities in end-stage renal disease in a high-risk population: the Southern Community Cohort Study

Racial disparities across multiple stages of the deceased organ donation process

Pervasive structural violence causes higher organ failure rates among Black Americans and excess Black potential deceased organ donors. Underuse of Black donors would exacerbate organ shortages that disproportionately harm Black transplant candidates. This study investigates racial differences in transit between distinct donation steps among 132 968 potential donors across 557 hospitals and 6 Organ Procurement Organizations (OPOs) from 2015 through 2021. Multilevel multistate modeling with patient covariates and OPO random effects shows adjusted likelihoods (95% confidence interval [CI]) of non-Black versus Black patients transitioning from OPO referral to approach: odds ratio (OR) 1.23 (95% CI 1.18, 1.27), approach to authorization: OR 1.64 (95% CI 1.56, 1.72), authorization to procurement: OR 1.08 (95% CI 1.02, 1.14), and procurement to transplant: OR 0.99 (95% CI 0.93, 1.04). Overall organ utilization rates for Black, Latino, White, and other OPO referrals were 5.88%, 8.17%, 6.78%, and 5.24%, respectively. Adjusting for patient covariates and hospital and OPO random effects, multilevel logistic models estimated that compared with Black patients, Latino, White, and other patients had ORs of organ utilization of 1.82 (95% CI 1.61, 2.04), 3.19 (95% CI 2.91, 3.50), and 1.25 (95% CI 1.06, 1.47), respectively. Nationwide in 2022, donor conversion disparities likely lost more than 1800 donors-70% of whom would have been Black. Achieving racial equity for transplant candidates will require reducing racial disparities in organ donation.

The mediating role of systemic inflammation and moderating role of racialization in disparities in incident dementia

BACKGROUND

Exposure to systemic racism is linked to increased dementia burden. To assess systemic inflammation as a potential pathway linking exposure to racism and dementia disparities, we investigated the mediating role of C-reactive protein (CRP), a systemic inflammation marker, and the moderating role of the racialization process in incident dementia.

METHODS

In the US Health and Retirement Study (n = 6,908), serum CRP was measured at baseline (2006, 2008 waves). Incident dementia was classified by cognitive tests over a six-year follow-up. Self-reported racialized categories were a proxy for exposure to the racialization process. We decomposed racialized disparities in dementia incidence (non-Hispanic Black and/or Hispanic vs. non-Hispanic white) into 1) the mediated effect of CRP, 2) the moderated portion attributable to the interaction between racialized group membership and CRP, and 3) the controlled direct effect (other pathways through which racism operates).

RESULTS

The 6-year cumulative incidence of dementia is 12%. Among minoritized participants (i.e., non-Hispanic Black and/or Hispanic), high CRP levels ( ≥ 75th percentile or 4.73μg/mL) are associated with 1.26 (95%CI: 0.98, 1.62) times greater risk of incident dementia than low CRP ( < 4.73μg/mL). Decomposition analysis comparing minoritized versus non-Hispanic white participants shows that the mediating effect of CRP accounts for 3% (95% CI: 0%, 6%) of the racial disparity, while the interaction effect between minoritized group status and high CRP accounts for 14% (95% CI: 1%, 27%) of the disparity. Findings are robust to potential violations of causal mediation assumptions.

CONCLUSIONS

Minoritized group membership modifies the relationship between systemic inflammation and incident dementia.

Role of Age and Competing Risk of Death in the Racial Disparity of Kidney Failure Incidence after Onset of CKD

SIGNIFICANCE STATEMENT

Black adults in the United States have 2-4 times higher incidence of kidney failure than White adults. Yet, the reasons underlying this disparity remain poorly understood. Among 547,188 US veterans with new-onset CKD, according to a new race-free GFR equation, Black veterans had a 2.5-fold higher cumulative incidence of kidney failure, compared with White veterans, in any follow-up period from CKD onset. This disparity resulted from a combination of higher hazards of progression to kidney failure and lower hazards of competing-risk death in Black veterans. Both, in turn, were largely explained by the younger age at CKD onset in Black veterans, underscoring an urgent need to prevent early onset and slow progression of CKD in younger Black adults.

BACKGROUND

The Black adult population is well known to have higher incidence of kidney failure than their White counterpart in the United States, but the reasons underlying this disparity are unclear. We assessed the racial differences in kidney failure and death from onset of CKD on the basis of the race-free 2021 CKD Epidemiology Collaboration equation and examined the extent to which these differences could be explained by factors at the time of CKD onset.

METHODS

We analyzed a national cohort consisting of 547,188 US veterans (103,821 non-Hispanic Black and 443,367 non-Hispanic White), aged 18-85 years, with new-onset CKD between 2005 and 2016 who were followed through 10 years or May 2018 for incident kidney failure with replacement therapy (KFRT) and pre-KFRT death.

RESULTS

At CKD onset, Black veterans were, on average, 7.8 years younger than White veterans. In any time period from CKD onset, the cumulative incidence of KFRT was 2.5-fold higher for Black versus White veterans. Meanwhile, Black veterans had persistently >2-fold higher hazards of KFRT throughout follow-up (overall hazard ratio [95% confidence interval], 2.38 [2.31 to 2.45]) and conversely had 17%-48% decreased hazards of pre-KFRT death. These differences were reduced after accounting for the racial difference in age at CKD onset.

CONCLUSIONS

The 2.5-fold higher cumulative incidence of kidney failure in Black adults resulted from a combination of higher hazards of progression to kidney failure and lower hazards of the competing risk of death, both of which can be largely explained by the younger age at CKD onset in Black compared with White adults.

Cardiometabolic Health in Asian American Children

Background

The aim was to compare cardiometabolic health between Asian American children and Non-Hispanic White (NHW) children as well as to compare cardiometabolic health among Asian American children by birthplace.

Methods

Children aged 6-17 years enrolled in the National Health and Nutrition Examination Survey (NHANES) from 2011-2018 who self-identified as non-Hispanic Asian and NHW were included. Among Asian Americans, place of birth was defined as foreign-born vs United States (US)-born. Regression models were adjusted for age, sex, household income, food insecurity, passive smoke exposure, and body mass index (BMI) z-score.

Results

Among 3369 children, 8.4% identified as Asian American (age 11.7 years) and 91.6% identified as NHW (age 11.7 years). Compared to NHW children, Asian American children had significantly lower BMI z-scores and odds of obesity. Asian American children had higher HOMA-IR and uric acid, and greater odds of dyslipidemia, microalbuminuria and glomerular hyperfiltration compared to NHW children. Among Asian Americans, 30.5% were foreign-born. Compared to foreign-born Asian American children, US-born Asian American children had significantly higher non-HDL, triglycerides, HOMA-IR and uric acid, lower HDL, and lower odds of hyperfiltration. There were no differences in blood pressure by racial group or place of birth.

Conclusions

Although Asian American children have lower odds of obesity, they have significantly worse glucose intolerance, higher serum uric acid levels, more dyslipidemia and more microalbuminuria compared to NHW children. US-born Asian American children have worse cardiometabolic health profiles compared to foreign-born Asian Americans.

Cross-sectional analysis of racial differences in hydration and neighborhood deprivation in young adults

BACKGROUND

Inadequate hydration is associated with cardiovascular and kidney disease morbidity and all-cause mortality. Compared with White individuals, Black individuals exhibit a higher prevalence of inadequate hydration, which may contribute to racial health disparities. However, the underlying reasons for these differences in hydration remain unclear.

OBJECTIVE

This cross-sectional study aimed to investigate whether neighborhood deprivation contributes to racial differences in hydration status.

METHODS

We assessed 24 Black and 30 White college students, measuring 24-hour urine osmolality, urine flow rate, urine specific gravity, and plasma copeptin concentration. Participants recorded their food and fluid intake for 3 d to assess total water intake from food and beverages. Neighborhood socioeconomic deprivation was measured using a tract-level Area Deprivation Index.

RESULTS

Black participants exhibited higher urine osmolality (640 [314] compared with 440 [283] mOsm/kg H2O, respectively, P = 0.006) and lower urine flow rate (1.06 [0.65] compared with 1.71 [0.89] ml/min, respectively, P = 0.009) compared with White participants, indicating greater hypohydration among Black participants. Black participants reported lower total water intake from food and beverages than White participants (2.3 ± 0.7 compared with 3.5 ± 1.1 L/day, respectively, P < 0.01). Black participants exhibited higher copeptin than White participants (6.3 [3.1] compared with 4.5 [2.3] pmol/L, P = 0.046), and urine osmolality mediated 67% of the difference (P = 0.027). Black participants reported greater cumulative exposure to neighborhood deprivation during childhood (ages 0-18 y). Furthermore, neighborhood deprivation during childhood was associated with urine specific gravity (P = 0.031) and total water intake from food and beverages (P = 0.042) but did not mediate the racial differences in these measures.

CONCLUSION

Our data suggest that compared with White young adults, Black young adults are hypohydrated and exhibit higher plasma copeptin concentration, and that greater neighborhood deprivation is associated with chronic underhydration irrespective of race. This trial was registered at clinicaltrials.gov as NCT04576338.

Age-Based Versus Young-Adult Thresholds for Nephrosclerosis on Kidney Biopsy and Prognostic Implications for CKD

SIGNIFICANCE STATEMENT

Nephrosclerosis (glomerulosclerosis, interstitial fibrosis, and tubular atrophy) is the defining pathology of both kidney aging and CKD. Optimal thresholds for nephrosclerosis that identify persons with a progressive disease are unknown. This study determined a young-age threshold (18-29 years) and age-based 95th percentile thresholds for nephrosclerosis on the basis of morphometry of kidney biopsy sections from normotensive living kidney donors. These thresholds were 7.1-fold to 36-fold higher in older (70 years or older) versus younger (aged 18-29 years) normotensive donors. Age-based thresholds, but not young-age threshold, were prognostic for determining risk of progressive CKD among patients who underwent a radical nephrectomy or a for-cause native kidney biopsy, suggesting that age-based thresholds are more useful than a single young-age threshold for identifying CKD on biopsy.

BACKGROUND

Nephrosclerosis, defined by globally sclerotic glomeruli (GSG) and interstitial fibrosis and tubular atrophy (IFTA), is a pathology of both kidney aging and CKD. A comparison of risk of progressive CKD using aged-based thresholds for nephrosclerosis versus a single young-adult threshold is needed.

METHODS

We conducted morphometric analyses of kidney biopsy images for %GSG, %IFTA, and IFTA foci density among 3020 living kidney donors, 1363 patients with kidney tumor, and 314 patients with native kidney disease. Using normotensive donors, we defined young-age thresholds (18-29 years) and age-based (roughly by decade) 95th percentile thresholds. We compared age-adjusted risk of progressive CKD (kidney failure or 40% decline in eGFR) between nephrosclerosis that was "normal compared with young," "normal for age but abnormal compared with young," and "abnormal for age" in patients with tumor and patients with kidney disease.

RESULTS

The 95th percentiles in the youngest group (18-29 years) to the oldest group (70 years or older) ranged from 1.7% to 16% for %GSG, 0.18% to 6.5% for %IFTA, and 8.2 to 59.3 per cm 2 for IFTA foci density. Risk of progressive CKD did not differ between persons with nephrosclerosis "normal compared with young" versus "normal for age but abnormal compared with young." Risk of progressive CKD was significantly higher with %GSG, %IFTA, or IFTA foci density that was abnormal versus normal for age in both cohorts.

CONCLUSIONS

Given that increased risk of progressive CKD occurs only when nephrosclerosis is abnormal for age, age-based thresholds for nephrosclerosis seem to be better than a single young-age threshold for identifying clinically relevant CKD.

The Mediating Role of Systemic Inflammation and Moderating Role of Race/Ethnicity in Racialized Disparities in Incident Dementia: A Decomposition Analysis

Background

Exposure to systemic racism is linked to increased dementia burden. To assess systemic inflammation as a potential pathway linking exposure to racism and dementia disparities, we investigated the mediating role of C-reactive protein (CRP), a systemic inflammation marker, and the moderating role of race/ethnicity on racialized disparities in incident dementia.

Methods

In the US Health and Retirement Study (n=5,143), serum CRP was measured at baseline (2006, 2008 waves). Incident dementia was classified by cognitive tests over a six-year follow-up. Self-reported racialized categories were a proxy for exposure to the racialization process. We decomposed racialized disparities in dementia incidence (non-Hispanic Black and/or Hispanic vs. non-Hispanic White) into 1) the mediated effect of CRP, 2) the moderated portion attributable to the interaction between racialized group membership and CRP, and 3) the controlled direct effect (other pathways through which racism operates).

Results

The 6-year cumulative incidence of dementia was 15.5%. Among minoritized participants (i.e., non-Hispanic Black and/or Hispanic), high CRP levels (> 75th percentile or 4.57mcg/mL) was associated with 1.27 (95%CI: 1.01,1.59) times greater risk of incident dementia than low CRP (<4.57mcg/mL). Decomposition analysis comparing minoritized versus non-Hispanic White participants showed that the mediating effect of CRP accounted for 2% (95% CI: 0%, 6%) of the racial disparity, while the interaction effect between minoritized group status and high CRP accounted for 12% (95% CI: 2%, 22%) of the disparity. Findings were robust to potential violations of causal mediation assumptions.

Conclusions

Systemic inflammation mediates racialized disparities in incident dementia.

Delivery of an at-home transcranial direct current stimulation intervention to mitigate pain in patients with end-stage kidney disease receiving hemodialysis (ESKD/HD)

Background

Poorly controlled pain remains a problem for many patients with end-stage kidney disease requiring hemodialysis (ESKD/HD) and customary approaches to pain management (e.g., opioids, non-steroidals) confer substantial risk. Accordingly, non-pharmacologic therapies are needed for use in this population. Non-invasive transcranial Direct Current Simulation (tDCS) constitutes a promising nonpharmacologic method for pain management in affected individuals.

Aims

This study seeks to: 1) determine the effects of an 8-week course of at-home tDCS vs. sham tDCS on pain intensity, pain interference, medication usage, quality of life, and mood; 2) determine if tDCS effects vary by race/ethnicity; and 3) ascertain patient satisfaction with device use.

Methods

This double-blind, randomized, sham-controlled clinical trial will enroll 100 ESKD/HD patients with moderate-to-severe (≥4 on 0-10 scale) chronic pain. The active study intervention consists of 20 min of tDCS delivered over the primary motor cortex 5 days/week for 8 weeks. The comparator is a sham procedure that provides no effective stimulation. The primary outcome analysis will evaluate efficacy of tDCS for pain reduction after two months of stimulation. We will also assess the effects of treatment on analgesic consumption, pain interference, depressed mood, and quality of life. The statistical plan will include fixed classification factors for treatment (vs. sham), clinic sites, and assessment time, and the interaction of these factors adjusting for covariates (e.g., race/ethnicity, pain level).

Conclusion

At-home tDCS constitutes a promising nonpharmacologic treatment for pain mitigation in persons with ESKD/HD. This unique RCT could transform the way pain is managed in this vulnerable population.

Trial Registration

NCT05311956.

The Mediating Role of Systemic Inflammation and Moderating Role of Race/Ethnicity in Racialized Disparities in Incident Dementia: A Decomposition Analysis

Background

Exposure to systemic racism is linked to increased dementia burden. To assess systemic inflammation as a potential pathway linking exposure to racism and dementia disparities, we investigated the mediating role of C-reactive protein (CRP), a systemic inflammation marker, and the moderating role of race/ethnicity on racialized disparities in incident dementia.

Methods

In the US Health and Retirement Study (n=5,143), serum CRP was measured at baseline (2006, 2008 waves). Incident dementia was classified by cognitive tests over a six-year follow-up. Self-reported racialized categories were a proxy for exposure to the racialization process. We decomposed racialized disparities in dementia incidence (non-Hispanic Black and/or Hispanic vs. non-Hispanic White) into 1) the mediated effect of CRP, 2) the moderated portion attributable to the interaction between racialized group membership and CRP, and 3) the controlled direct effect (other pathways through which racism operates).

Results

The 6-year cumulative incidence of dementia was 15.5%. Among minoritized participants (i.e., non-Hispanic Black and/or Hispanic), high CRP levels (> 75th percentile or 4.57μg/mL) was associated with 1.27 (95%CI: 1.01,1.59) times greater risk of incident dementia than low CRP (≤4.57μg/mL). Decomposition analysis comparing minoritized versus non-Hispanic White participants showed that the mediating effect of CRP accounted for 2% (95% CI: 0%, 6%) of the racial disparity, while the interaction effect between minoritized group status and high CRP accounted for 12% (95% CI: 2%, 22%) of the disparity. Findings were robust to potential violations of causal mediation assumptions.

Conclusions

Systemic inflammation mediates racialized disparities in incident dementia.

Cardiovascular Risk Factor Prevalence, Treatment, and Control in US Adults Aged 20 to 44 Years, 2009 to March 2020

Importance

Declines in cardiovascular mortality have stagnated in the US over the past decade, in part related to worsening risk factor control in older adults. Little is known about how the prevalence, treatment, and control of cardiovascular risk factors have changed among young adults aged 20 to 44 years.

Objective

To determine if the prevalence of cardiovascular risk factors (hypertension, diabetes, hyperlipidemia, obesity, and tobacco use), treatment rates, and control changed among adults aged 20 to 44 years from 2009 through March 2020, overall and by sex and race and ethnicity.

Design, Setting, and Participants

Serial cross-sectional analysis of adults aged 20 to 44 years in the US participating in the National Health and Nutrition Examination Survey (2009-2010 to 2017-March 2020).

Main Outcomes and Measures

National trends in the prevalence of hypertension, diabetes, hyperlipidemia, obesity, and smoking history; treatment rates for hypertension and diabetes; and blood pressure and glycemic control in those receiving treatment.

Results

Among 12 924 US adults aged 20 to 44 years (mean age, 31.8 years; 50.6% women), the prevalence of hypertension was 9.3% (95% CI, 8.1%-10.5%) in 2009-2010 and 11.5% (95% CI, 9.6%-13.4%) in 2017-2020. The prevalence of diabetes (from 3.0% [95% CI, 2.2%-3.7%] to 4.1% [95% CI, 3.5%-4.7%]) and obesity (from 32.7% [95% CI, 30.1%-35.3%] to 40.9% [95% CI, 37.5%-44.3%]) increased from 2009-2010 to 2017-2020, while the prevalence of hyperlipidemia decreased (from 40.5% [95% CI, 38.6%-42.3%] to 36.1% [95% CI, 33.5%-38.7%]). Black adults had high rates of hypertension across the study period (2009-2010: 16.2% [95% CI, 14.0%-18.4%]; 2017-2020: 20.1% [95% CI, 16.8%-23.3%]), and significant increases in hypertension were observed among Mexican American adults (from 6.5% [95% CI, 5.0%-8.0%] to 9.5% [95% CI, 7.3%-11.7%]) and other Hispanic adults (from 4.4% [95% CI, 2.1%-6.8%] to 10.5% [95% CI, 6.8%-14.3%]), while Mexican American adults had a significant rise in diabetes (from 4.3% [95% CI, 2.3%-6.2%] to 7.5% [95% CI, 5.4%-9.6%]). The percentage of young adults treated for hypertension who achieved blood pressure control did not significantly change (from 65.0% [95% CI, 55.8%-74.2%] in 2009-2010 to 74.8% [95% CI, 67.5%-82.1%] in 2017-2020], while glycemic control among young adults receiving treatment for diabetes remained suboptimal throughout the study period (2009-2010: 45.5% [95% CI, 27.7%-63.3%]) to 2017-2020: 56.6% [95% CI, 39.2%-73.9%]).

Conclusions and Relevance

In the US, diabetes and obesity increased among young adults from 2009 to March 2020, while hypertension did not change and hyperlipidemia declined. There was variation in trends by race and ethnicity.

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.

Progression of chronic kidney disease among black patients attending a tertiary hospital in Johannesburg, South Africa

BACKGROUND

Chronic kidney disease (CKD) is a major public health issue worldwide and is an important contributor to the overall non-communicable disease burden. Chronic kidney disease is usually asymptomatic, and insidiously and silently progresses to advanced stages in resource limited settings.

METHODOLOGY

A prospective longitudinal study was carried out on black patients with CKD attending the kidney outpatient clinic at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in South Africa, between September 2019 to March 2022. Demographic and clinical data were extracted from the ongoing continuous clinic records, as well as measurements of vital signs and interviews at baseline and at follow up. Patients provided urine and blood samples for laboratory investigations as standard of care at study entry (0) and at 24 months, and were followed up prospectively for two (2) years. Data were descriptively and inferentially entered into REDcap and analysed using STATA version 17, and multivariable logistic regression analysis was used to identify predictors of CKD progression.

RESULTS

A total of 312 patients were enrolled into the study, 297 (95.2%) patients completed the study, 10 (3.2%) patients were lost to follow and 5 (1.6%) patients died during the study period. The prevalence of CKD progression was 49.5%, while that of CKD remission was 33% and CKD regression was 17.5%. For patients with CKD progression the median age at baseline was 58 (46-67) years, the median eGFR was 37 (32-51) mL/min/1.73 m2, median urine protein creatinine ratio (uPCR) was 0.038 (0.016-0.82) g/mmol and the median haemoglobin (Hb) was 13.1 (11.7-14.4) g/dl; 95.2% had hypertension, 40.1% patients had diabetes mellitus and 39.5% had both hypertension and diabetes mellitus. Almost half (48.3%) of patients with CKD progression had severely increased proteinuria and 45.6% had anaemia. Variables associated with higher odds for CKD progression after multivariable logistic regression analysis were severely increased proteinuria (OR 32.3, 95% CI 2.8-368.6, P = 0.005), moderately increased proteinuria (OR 23.3, 95% CI 2.6-230.1, P = 0.007), hypocalcaemia (OR 3.8, 95% CI 1.0-14.8, P = 0.047), hyponatraemia (OR 4.5, 95% CI 0.8-23.6, P = 0.042), anaemia (OR 2.1, 95% CI 1.0-4.3, P = 0.048), diabetes mellitus (OR 1.8, 95% CI 0.9-3.6, P = 0.047), elevated HbA1c (OR 1.8, 95% CI 1.2-2.8, P = 0.007) and current smoking (OR 2.8, 95% CI 0.9-8.6, P = 0.049).

CONCLUSION

Our study identified a higher prevalence of CKD progression in a prospective longitudinal study of black patients with CKD compared with literature reports. CKD Progression was associated with proteinuria, diabetes mellitus, elevated HbA1c, anaemia, hypocalcaemia, hyponatraemia and current smoking in a cohort of black patients with CKD who had controlled hypertension and diabetes mellitus at baseline.

Use of hospitals in the New York City Metropolitan Region, by race: how separate? How equal in resources and quality?

BACKGROUND

Although racial and ethnic minorities disproportionately use some hospitals, hospital-based racial and ethnic composition relative to geographic region and its association with quality indicators has not been systematically analyzed.

METHODS

We used four race and ethnicity categories: non-Hispanic white (NHW), non-Hispanic black (NHB), Hispanic, and Asian/Pacific Islander/Alaskan Native/American Indian (API/AIAN), as well as a combined non-NHW category, from the 2010 (latest year publicly available) Medicare Institutional Provider & Beneficiary Summary public use file for 84 hospitals in the New York City region. We assessed the relative distribution of race and ethnicity across hospitals grouped at different geographic levels (region, county, hospital referral region [HRR], or hospital service areas [HSA]) using the dissimilarity index. Hospital characteristics included quality star ratings, essential professional services and diagnostic/treatment equipment, bed size, total expenses, and patients with dual Medicare and Medicaid enrollment. We assessed Spearman's rank correlation between hospital-based racial and ethnic composition and quality/structural measures.

RESULTS

Dissimilarity Index decreases from region (range 30.3-40.1%) to county (range 13.7-23.5%), HRR (range 10.5-27.5%), and HSA (range 12.0-16.9%) levels. Hospitals with larger non-NHW patients tended to have lower hospital ratings and higher proportions of dually-enrolled patients. They were also more likely to be safety net hospitals and non-federal governmental hospitals.

CONCLUSIONS

In the NYC metropolitan region, there is considerable hospital-based racial and ethnic segregation of Medicare patients among non-NHW populations, extending previous research limited to NHB. Availability of data on racial and ethnic composition of hospitals should be made publicly available for researchers and consumers.

Clinical Features of ANCA-Associated Vasculitis in African American Patients in the United States: A Single-Center Medical Records Review Study

BACKGROUND/PURPOSE

The aim of this study was to compare the clinical features at presentation of ANCA-associated vasculitis (AAV) between African American (AA) and White patients.

METHODS

This is a chart review of cases between January 2003 and December 2018. African American patients with AAV were identified and matched in a 1:2 ratio with White comparators based on the year of diagnosis (±4 years). Data on demographics, clinical, and laboratory features and outcomes at presentation were collected. Descriptive statistics were used to compare the characteristics between groups.

RESULTS

Thirty-two of 56 AA patients with AAV had complete data and were included for analysis. When compared with 64 matched White patients with AAV, AA patients were younger (47.5 vs 61.0 years, p = 0.001). Compared with White patients, AA patients with granulomatosis with polyangiitis (GPA) (35 vs 55 years, p = 0.0006) and microscopic polyangiitis (MPA) (55.5 vs 65.0 years, p = 0.05) were younger. African American patients with GPA were more frequently female (p = 0.008), whereas AA patients with MPA were more frequently male (p = 0.03). No differences in disease manifestations, disease activity, and outcomes were observed between AA and White patients with AAV.

CONCLUSIONS

In this single-center study, AA patients with AAV were diagnosed at a younger age than Whites; this was found in both the GPA and MPA disease phenotypes. No other significant differences were observed. Future studies are needed to confirm our findings and better describe differences of AAV in racial/ethnic minorities.

Serum Phosphorus and Pill Burden Among Hemodialysis Patients Prescribed Sucroferric Oxyhydroxide: One-Year Follow-Up on a Contemporary Cohort

Purpose

In prior analyses of real-world cohorts of hemodialysis patients switched from one phosphate binder (PB) to sucroferric oxyhydroxide (SO), SO therapy has been associated with improvements in serum phosphorus (sP) and reductions in daily PB pill burden. To characterize how SO initiation patterns have changed over time, we examined the long-term effectiveness of SO in a contemporary (2018–2019) cohort.

Patients and Methods

Adult Fresenius Kidney Care hemodialysis patients first prescribed SO monotherapy as part of routine care between May 2018 and May 2019 (N = 1792) were followed for 1 year. All patients received a non-SO PB during a 91-day baseline period before SO prescription. Mean PB pills/day and laboratory parameters were compared before and during SO treatment. Results were divided into consecutive 91-day intervals (Q1–Q4) and analyzed using linear mixed-effects regression and Cochran’s Q test. These results were contrasted with findings from a historical (2014–2015) cohort (N = 530).

Results

The proportion of patients achieving sP ≤5.5 mg/dl increased after switching to SO (from 27.0% at baseline to 37.8%, 45.1%, 44.7%, and 44.0% at Q1, Q2, Q3, and Q4, respectively; P < 0.0001 for all). The mean daily PB pill burden decreased from a baseline of 7.7 to 4.4, 4.6, 4.8, and 4.9, respectively, across quarters (P < 0.0001 for all). Patients in the contemporary cohort had improved sP control (27.0% achieving sP ≤5.5 mg/dl vs 17.7%) and lower daily PB pill burden (mean 7.7 vs 8.5 pills/day) at baseline than those in the historical cohort. Overall use of active vitamin D was similar between cohorts, although higher use of oral active vitamin D (63.9% vs 15.7%) and lower use of IV active vitamin D lower (23.4% vs 74.2%) was observed in the contemporary cohort.

Conclusion

Despite evolving treatment patterns, switching to SO resulted in improved sP control with fewer pills per day in this contemporary hemodialysis cohort.

Rising Incidence of Legionnaires' Disease and Associated Epidemiologic Patterns, United States, 1992-2018

Reported Legionnaires' disease (LD) cases began increasing in the United States in 2003 after relatively stable numbers for >10 years; reasons for the rise are unclear. We compared epidemiologic patterns associated with cases reported to the Centers for Disease Control and Prevention before and during the rise. The age-standardized average incidence was 0.48 cases/100,000 population during 1992-2002 compared with 2.71 cases/100,000 in 2018. Reported LD incidence increased in nearly every demographic, but increases tended to be larger in demographic groups with higher incidence. During both periods, the largest number of cases occurred among White persons, but the highest incidence was in Black or African American persons. Incidence and increases in incidence were generally largest in the East North Central, Middle Atlantic, and New England divisions. Seasonality was more pronounced during 2003-2018, especially in the Northeast and Midwest. Rising incidence was most notably associated with increasing racial disparities, geographic focus, and seasonality.

The Vanderbilt O'Brien Kidney Center

The Vanderbilt O'Brien Kidney Center (VOKC) is one of the eight National Institutes of Health P30-funded centers in the United States. The mission of these core-based centers is to provide technical and conceptual support to enhance and facilitate research in the field of kidney diseases. The goal of the VOKC is to provide support to understand mechanisms and identify potential therapies for acute and chronic kidney disease. The services provided by the VOKC are meant to help the scientific community to have the right support and tools as well as to select the right animal model, statistical analysis, and clinical study design to perform innovative research and translate discoveries into personalized care to prevent, diagnose, and cure kidney disease. To achieve these goals, the VOKC has in place a program to foster collaborative investigation into critical questions of kidney disease, to personalize diagnosis and treatment of kidney disease, and to disseminate information about kidney disease and the benefits of VOKC services and research. The VOKC is complemented by state-of-the-art cores and an education and outreach program whose goals are to provide an educational platform to enhance the study of kidney disease, to publicize information about services available through the VOKC, and to provide information about kidney disease to patients and other interested members of the community. In this review, we highlight the major services and contributions of the VOKC.

Implications of institutional racism in the therapeutic itinerary of people with chronic renal failure

OBJECTIVES

To understand the implications of institutional racism in the therapeutic itinerary of patients with chronic renal failure (CRF) in the search for diagnosis and treatment of the disease.

METHODS

Descriptive, qualitative study developed with 23 people with CRF in a regional reference hospital for hemodialysis treatment in Northeast Brazil. Two techniques of data collection were used: semi-structured interview and consultation to the NEFRODATA electronic medical record. For systematization and analysis, the technique of content analysis was used.

RESULTS

Black and white people with CRF showed significant divergences and differences in their therapeutic itineraries: while white people had access to diagnosis during outpatient care in other medical specialties, black people were only diagnosed during hospitalization. In addition, white people had more access to private health plans when compared to black people, which doubles the possibility of access to health services. Moreover, even when the characteristics in the itinerary of black and white people were convergent, access to diagnosis and treatment proved to be more difficult for black people.

CONCLUSIONS

The study showed the presence of institutional racism in the therapeutic itinerary of people with kidney disease in which black people have greater difficulty in accessing health services. In this sense, there is a need to create strategies to face institutional racism and to consolidate the National Policy for Comprehensive Health Care of the Black Population.

The association of exercise and sedentary behaviours with incident end-stage renal disease: the Southern Community Cohort Study

OBJECTIVE

To examine whether lifestyle factors, including sedentary time and physical activity, could independently contribute to risk of end-stage renal disease (ESRD).

STUDY DESIGN

Case-cohort study.

SETTING

South-eastern USA.

PARTICIPANTS

The Southern Community Cohort Study recruited ~86 000 black and white participants from 2002 to 2009. We assembled a case cohort of 692 incident ESRD cases and a probability sample of 4113 participants.

PREDICTORS

Sedentary time was calculated as hours/day from daily sitting activities. Physical activity was calculated as metabolic equivalent (MET)-hours/day from engagement in light, moderate and vigorous activities.

OUTCOMES

Incident ESRD.

RESULTS

At baseline, among the subcohort, mean (SD) age was 52 (8.6) years, and median (25th, 75th centile) estimated glomerular filtration rate (eGFR) was 102.8 (85.9-117.9) mL/min/1.73 m². Medians (25th-75th centile) for sedentary time and physical activity were 8.0 (5.5-12.0) hours/day and 17.2 (8.7-31.9) MET-hours/day, respectively. Median follow-up was 9.4 years. We observed significant interactions between eGFR and both physical activity and sedentary behaviour (p<0.001). The partial effect plot of the association between physical activity and log relative hazard of ESRD suggests that ESRD risk decreases as physical activity increases when eGFR is 90 mL/min/1.73 m². The inverse association is most pronounced at physical activity levels >27 MET-hours/day. High levels of sitting time were associated with increased ESRD risk only among those with reduced kidney function (eGFR ≤30 mL/min/1.73 m²); this association was attenuated after excluding the first 2 years of follow-up.

CONCLUSIONS

In a population with a high prevalence of chronic kidney disease risk factors such as hypertension and diabetes, physical activity appears to be associated with reduced risk of ESRD among those with preserved kidney function. A positive association between sitting time and ESRD observed among those with advanced kidney disease is likely due to reverse causation.