Racial and ethnic disparities in end-stage kidney failure-survival paradoxes in African-Americans

Pressure Ulcer Diagnosis Is Associated with Increased Mortality in Patients with End-Stage Renal Disease: A Retrospective Study

Pressure ulcers are associated with multiple comorbidities and annually affect approximately 3 million Americans, directly accounting for approximately 60,000 deaths per year. Because patients with end-stage renal disease (ESRD) are known to present with unique factors which impair wound healing, pressure ulcers diagnosed in ESRD patients might independently increase the risk of mortality. To investigate the association between pressure ulcer diagnosis and mortality risk in the ESRD population, a retrospective analysis of the United States Renal Data System (USRDS) database was performed. The records of 1,526,366 dialysis patients who began therapy between 1 January 2005 and 31 December 2018 were included. Our analysis showed that the diagnosis of pressure ulcers in this population was independently associated with mortality even after controlling for confounding factors (p < 0.001). A Kaplan-Meier survival analysis demonstrated reduced survival in patients with a pressure ulcer diagnosis compared to those without a pressure ulcer diagnosis. These results establish pressure ulcers as a significant independent risk factor for mortality, as well as suggesting several comorbidities as potential risk factors for pressure ulcers in the ESRD population.

Proximal aortic repair in dialysis patients: A national database analysis

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Serum Cystatin-C is linked to increased prevalence of diabetes and higher risk of mortality in diverse middle-aged and older adults

Objective

Type 2 Diabetes Mellitus (henceforth diabetes) affects roughly 35 million individuals in the US and is a major risk factor for cardiovascular and kidney disease. Serum Cystatin-C is used to monitor renal function and detect kidney damage. Recent research has focused on linking Cystatin-C to cardiovascular risk and disease, but most findings focus on small sample sizes and generalize poorly to diverse populations, thus limiting epidemiological inferences. The aim of this manuscript is to study the association between Cystatin-C, diabetes, and mortality and test for possible sex or racial/ethnic background modifications in these relationships.

Methods

We analyzed 8-years of biennial panel data from Health and Retirement Study participants 50-years and older who self-identified as White (unweighted N (uN) = 5,595), Black (uN = 867), or Latino (uN = 565) for a total of uN = 7,027 individuals. We modeled diabetes and death over 8-years as function of baseline Cystatin-C (log transformed) adjusting for covariates and tested modifications in associations by race/ethnic background and sex.

Results

Mean log Cystatin-C at visit 1 was 0.03±0.32 standard deviation. A 10% increase in Cystatin-C levels was associated with 13% increased relative risk of diabetes at baseline (11% and 9% by years 4 and 8). A 10% increase in Cystatin-C was highly associated with increased relative risk of death (28% and 31% by years 4 and 8). These associations were present even after adjusting for possible confounders and were not modified by sex or racial/ethnic background.

Conclusion

Despite differential risks for diabetes and mortality by racial/ethnic groups, Cystatin-C was equally predictive of these outcomes across groups. Cystatin-C dysregulations could be used as a risk indicator for diabetes and as a warning sign for accelerated risk of mortality.

Physical Resilience Phenotype Trajectories in Incident Hemodialysis: Characterization and Mortality Risk Assessment

Introduction

Methods

Results

Conclusion

County-Level Characteristics Associated with Variation in ESKD Mortality in the United States, 2010-2018

Background

Geographic and neighborhood-level factors, such as poverty and education, have been associated with an increased risk for incident ESKD, likelihood of receiving pre-ESKD care, and likelihood of receiving a transplant. However, few studies have examined whether these same factors are associated with ESKD mortality. In this study, we examined county-level variation in ESKD mortality and identified county-level characteristics associated with this variation.

Methods

We identified 1,515,986 individuals (aged 18-84 years) initiating RRT (dialysis or transplant) between 2010 and 2018 using the United States Renal Data System. Among 2781 counties, we estimated county-level, all-cause, age-standardized mortality rates (ASMR) among patients with ESKD. We then identified county-level demographic (e.g., percent female), socioeconomic (e.g., percent unemployed), healthcare (e.g., percent without health insurance), and health behavior (e.g., percent current smokers) characteristics associated with ASMR using multivariable hierarchic linear mixed models and quantified the percentage of ASMR variation explained by county-level characteristics.

Results

County-level ESKD ASMR ranged from 45 to 1022 per 1000 person-years (PY) (mean, 119 per 1000 PY). ASMRs were highest in counties located in the Tennessee Valley and Appalachia regions, and lowest in counties located in New England, the Pacific Northwest, and Southern California. In fully adjusted models, county-level characteristics significantly associated with higher ESKD mortality included a lower percentage of Black residents (-4.94 per 1000 PY), lower transplant rate (-4.08 per 1000 PY), and higher healthcare expenditures (5.21 per 1000 PY). Overall, county-level characteristics explained 19% of variation in ESKD mortality.

Conclusions

Counties with high ESKD-related mortality may benefit from targeted and multilevel interventions that combine knowledge from a growing evidence base on the interplay between individual and community-level factors associated with ESKD mortality.

Changes in excess mortality among adults with diabetes-related end-stage kidney disease: a comparison between the USA and Australia

BACKGROUND

The number of people with diabetes-related end-stage kidney disease (ESKD-DM) has doubled in the last two decades. We examined changes in excess mortality for people with ESKD-DM in the USA and Australia.

METHODS

In this retrospective cohort study, we included adults (ages 20-84 years) receiving renal replacement therapy (RRT) for ESKD-DM in the USA (n = 1 178 860 from the United States Renal Data System, 2002-17) and Australia (n = 10 381 from the Australia and New Zealand Dialysis and Transplant Registry, 2002-13). ESKD-DM was defined as those with diagnosed diabetes at time of RRT initiation and mortality status was captured from national death registries. Annual standardized mortality ratios (SMR) were stratified by treatment modality, and age, sex and race (USA only). Trends were assessed using join point regression and annual percent change (APC) was reported.

RESULTS

Overall, in the dialysis population SMR decreased from 2006 to 2014 in the USA (from 12.0 to 10.1; APC -2.1) and from 2002 to 2013 in Australia (from 12.0 to 9.4; APC -3.4). In the transplant population, SMR decreased from 6.2 to 4.0 from 2002 to 2013 in the USA, and did not significantly change from 2002 to 2013 in Australia. By subgroup, excess mortality was higher in women (versus men), younger (versus older) adults, dialysis (versus transplant) patients, and in Asian or Pacific Islanders and American Indian or Alaskan Natives (AI/AN) (versus Whites and Blacks). SMRs declined similarly across all subgroups excluding AI/AN (USA) and transplant patients (Australia), where relative declines were smaller.

CONCLUSIONS

Excess mortality for people with ESKD-DM treated with dialysis or transplant has decreased in the USA and Australia, but progress has stalled from ∼2013 in the USA. Nevertheless, mortality remains more than nine times higher in ESKD-DM versus the general population, with important variations by subgroups. Given the increasing burden of diabetes in the population, a focus on reducing excess mortality risk in the ESKD-DM population is needed.

Age Based Outcomes of Autogenous Fistulas for Hemodialysis Access

INTRODUCTION

Hemodialysis (HD) dependence and autogenous fistula use for HD span the spectrum of age. This study examines age related outcomes of autogenous fistulas for hemodialysis access in a large population-based cohort of patients.

METHODS

A retrospective cohort study of all patients who initiated hemodialysis in the United States Renal Database System (2007-2014). Chi-square, T-tests, Kaplan-Meier, log-rank tests, multivariable logistic and Cox regression analyses were employed to evaluate access maturation, interventions, patency, and mortality.

RESULTS

Of the 303281 patients studied, 48892 (16.1%) were younger than 50 years, 55817 (18.4%) were 50-59 years, 79138 (26.1%) were 60-69 years, 75200 (24.8%) were 70-79 years and 44234 (14.6%) were 80 years or older. There was a decrease in autogenous fistula maturation with increasing age. Primary patency at 5 years comparing patients <50 vs. 50-59 vs. 60-69 vs. 70-79 vs. 80+ was 24 vs. 23 vs. 21 vs. 20 vs. 18% (p<0.001). Primary assisted patency at 5 years was 38 vs. 40 vs. 37 vs. 35 vs. 33% (p<0.001). Secondary patency at 5 years was 48 vs. 50 vs. 47 vs. 45 vs. 42% (p<0.001). The risk adjusted analyses revealed a progressive decrease in primary, primary assisted and secondary patency with increasing age. As expected, patient survival decreased with increasing age.

CONCLUSIONS

In this population-based cohort of hemodialysis patients, there was a decrease in autogenous fistula maturation, primary patency, primary assisted patency, secondary patency and patient survival with increasing age. Despite the relative decline in outcomes associated with older age, decisions about AV access creation in older patients should be individualized taking overall clinical status and outcomes of alternatives modes of access into consideration.

Long-term mortality among kidney transplant recipients with and without diabetes: a nationwide cohort study in the USA

INTRODUCTION

Little is known about the role diabetes (type 1 (T1D) and type 2 (T2D)) plays in modifying prognosis among kidney transplant recipients. Here, we compare mortality among transplant recipients with T1D, T2D and non-diabetes-related end-stage kidney disease (ESKD).

RESEARCH DESIGN AND METHODS

We included 254 188 first-time single kidney transplant recipients aged ≥18 years from the US Renal Data System (2000-2018). Diabetes status, as primary cause of ESKD, was defined using International Classification of Disease 9th and 10th Clinical Modification codes. Multivariable-adjusted Cox regression models (right-censored) computed risk of death associated with T1D and T2D relative to non-diabetes. Trends in standardized mortality ratios (SMRs) (2000-2017), relative to the general US population, were assessed using Joinpoint regression.

RESULTS

A total of 72 175 (28.4%) deaths occurred over a median survival time of 14.6 years. 5-year survival probabilities were 88%, 85% and 77% for non-diabetes, T1D and T2D, respectively. In adjusted models, mortality was highest for T1D (HR=1.95, (95% CI: 1.88 to 2.03)) and then T2D (1.65 (1.62 to 1.69)), as compared with non-diabetes. SMRs declined for non-diabetes, T1D, and T2D. However, in 2017, SMRs were 2.38 (2.31 to 2.45), 6.55 (6.07 to 7.06), and 3.82 (3.68 to 3.98), for non-diabetes, T1D and T2D, respectively.

CONCLUSIONS

In the USA, diabetes type is an important modifier in mortality risk among kidney transplant recipients with highest rates among people with T1D-related ESKD. Development of effective interventions that reduce excess mortality in transplant recipients with diabetes is needed, especially for T1D.

Association of Race with In-Hospital and Post-Hospitalization Mortality in Patients with Acute Kidney Injury

INTRODUCTION

Acute kidney injury (AKI) is known to be associated with increased mortality, and racial differences in hospital mortality exist in patients with AKI. However, it remains to be seen whether racial differences exist in post-hospitalization mortality among AKI patients.

METHODS

We analyzed data of adult AKI patients admitted to the University of Virginia Medical Center between January 1, 2001, and December 31, 2015, to compare in-hospital and post-hospitalization mortality among hospitalized black and white patients with AKI. Multivariable logistic regression analysis was used to analyze the association between race and in-hospital mortality, and 90-day post-hospitalization mortality among AKI patients that were discharged. Kaplan-Meier survival curve was used to evaluate long-term survival between black and white patients.

RESULTS

Black patients had lower in-hospital mortality than white patients after adjusting for age, sex, estimated glomerular filtration rate, hospital length of stay, severity of AKI, comorbidities, and the need for dialysis and mechanical ventilation (odds ratio: 0.82; 95% confidence interval, 0.70-0.96, p = 0.0015). Similarly, at 90-day post-hospitalization, black patients had significantly lower adjusted odds of death than white patients (odds ratio: 0.64; 95% confidence interval, 0.46-0.93; p = 0.008). The median length of follow-up was 11.9 months (0.6-46.7 months). Kaplan-Meier survival curve showed that long-term survival was significantly better in black patients compared to white patients (median duration of survival; 39.7 vs. 24.8 months; p ≤ 0.001).

CONCLUSIONS

Black patients with AKI had lower in-hospital mortality, 90-day post-hospitalization mortality, and better long-term survival rates compared to white patients with AKI.

Hemodialysis Adequacy and Its Impact on Long-Term Patient Survival in Demographically, Socially, and Culturally Homogeneous Patients

Background

Impact of hemodialysis adequacy on patient survival is extensively studied. The current study compares the survival of chronic hemodialyzed, undocumented, uninsured, Afghan immigrant patients with that of a group of insured Iranian patients matched for underlying disease, age, weight, level of education, marital status, income, and number of comorbid conditions.

Methods

Eighty chronic hemodialysis patients (mean age 42.8 ± 10.5 years) entered this historical cohort study in Mashhad, Iran, between January 2012 and January 2015. Half of the patients were undocumented, uninsured, Afghan immigrants (Group A) matched with forty insured Iranian patients (Group B). To compare the survival rate of the two patient groups, Kaplan–Meir survival analysis test was used.

Results

Group A patients were underdialyzed with a weekly Kt/V which was significantly less in comparison with that of Group B (1.63 ± 0.63 versus 2.54 ± 0.12, p value = 0.01). While Group A's number of hemodialysis sessions per week was fewer than that of Group B (1.45 ± 0.56 versus 2.8 ± 0.41, p value = 0.04), the mean of Kt/V in each hemodialysis session was higher in them, in comparison with Group B (1.43 ± 0.25 versus 1.3 ± 0.07, p value = 0.045). In Group B and Group A patients, one-year survival was 70% versus 50%, two-year survival was 55% versus 30%, and three-year survival was 40% versus 20%, respectively (p values = 0.04, 0.02 and 0.04, respectively). In Cox regression analysis, hemodialysis adequacy and uninsurance were factors impacting patients' survival (OR = 1.193 and 0.333, respectively).

Conclusions

Undocumented, uninsured, inadequately hemodialyzed, Afghan patients had a significantly lower one-, two-, and three-year survival as opposed to their Iranian counterparts, probably due to lack of insurance.

Racial/Ethnic Disparities in Atrial Fibrillation Treatment and Outcomes among Dialysis Patients in the United States

BACKGROUND

Because stroke prevention is a major goal in the management of ESKD hemodialysis patients with atrial fibrillation, investigating racial/ethnic disparities in stroke among such patients is important to those who could benefit from strategies to maximize preventive measures.

METHODS

We used the United States Renal Data System to identify ESKD patients who initiated hemodialysis from 2006 to 2013 and then identified those with a subsequent atrial fibrillation diagnosis and Medicare Part A/B/D. Patients were followed for 1 year for all-cause stroke, mortality, prescription medications, and cardiovascular disease procedures. The survival mediational g-formula quantified the percentage of excess strokes attributable to lower use of atrial fibrillation treatments by race/ethnicity.

RESULTS

The study included 56,587 ESKD hemodialysis patients with atrial fibrillation. Black, white, Hispanic, and Asian patients accounted for 19%, 69%, 8%, and 3% of the population, respectively. Compared with white patients, black, Hispanic, or Asian patients were more likely to experience stroke (13%, 15%, and 16%, respectively) but less likely to fill a warfarin prescription (10%, 17%, and 28%, respectively). Warfarin prescription was associated with decreased stroke rates. Analyses suggested that equalizing the warfarin distribution to that in the white population would prevent 7%, 10%, and 12% of excess strokes among black, Hispanic, and Asian patients, respectively. We found no racial/ethnic disparities in all-cause mortality or use of cardiovascular disease procedures.

CONCLUSIONS

Racial/ethnic disparities in all-cause stroke among hemodialysis patients with atrial fibrillation are partially mediated by lower use of anticoagulants among black, Hispanic, and Asian patients. The reasons for these disparities are unknown, but strategies to maximize stroke prevention in minority hemodialysis populations should be further investigated.

Age-related outcomes of arteriovenous grafts for hemodialysis access

BACKGROUND

The prevalence of end-stage renal disease spans the spectrum of age. Arteriovenous grafts are viable alternatives for hemodialysis access in patients whose anatomy precludes placement of an arteriovenous fistula. This report describes the age-related outcomes after arteriovenous graft placement in a population-based cohort.

METHODS

A retrospective cohort study was conducted of all patients who initiated hemodialysis in the U.S. Renal Data System (2007-2014). The χ² test, t-test, Kaplan-Meier analysis, log-rank test, and multivariable logistic and Cox regression analyses were employed to evaluate access maturation, interventions, patency, and mortality.

RESULTS

Of the 78,341 patients studied, 10,150 (13%) were younger than 50 years, 13,167 (16.8%) were 50 to 59 years, 19,975 (25.5%) were 60 to 69 years, 20,307 (25.9%) were 70 to 79 years, and 14,742 (18.8%) were 80+ years. There was no significant difference in access maturation time for patients in the older age categories compared to patients younger than 50 years. Primary patency at 5 years comparing <50 years vs 50 to 59 years vs 60 to 69 years vs 70 to 79 years vs 80+ years was 12% vs 12% vs 9% vs 9% vs 8% (P < .001). Primary assisted patency at 5 years was 20% vs 21% vs 18% vs 17% vs 14% (P < .001). Secondary patency at 5 years was 36% vs 39% vs 36% vs 30% vs 31% (P < .001). There was no significant difference in primary patency (adjusted hazard ratio [aHR], 1.00; 95% confidence interval [CI], 1.00-1.00; P < .001), primary assisted patency (aHR, 1.00; 95% CI, 1.00-1.00; P < .001), and secondary patency (aHR, 1.00; 95% CI, 1.00-1.00; P = .029) with increasing age. However, there was a decrease in severe prosthetic graft infection requiring graft excision (aHR, 0.99; 95% CI, 0.99-0.99; P < .001) and increase in mortality (aHR, 1.03; 95% CI, 1.03-1.03; P < .001) for the older age categories compared with the younger patients.

CONCLUSIONS

In this population-based cohort of hemodialysis patients, there was no significant association between older age and prosthetic graft maturation or patency. However, older age was associated with a decrease in severe graft infection and the expected increase in mortality.

Risk of Cardiovascular Disease and Mortality in Young Adults With End-stage Renal Disease: An Analysis of the US Renal Data System

Importance

Cardiovascular disease (CVD) is a leading cause of death among patients with end-stage renal disease (ESRD). Young adult (ages 22-29 years) have risks for ESRD-associated CVD that may vary from other ages.

Objective

To test the hypothesis that young adult-onset ESRD is associated with higher cardiovascular (CV) hospitalizations and mortality with different characteristics than childhood-onset disease.

Design, Setting, and Participants

This population-based cohort study used the US Renal Data System to categorize patients who initiated ESRD care between 2003 and 2013 by age at ESRD onset (1-11, 12-21, and 22-29 years). Cardiovascular hospitalizations were identified via International Classification of Diseases, Ninth Revision discharge codes and CV mortality from the Centers for Medicare & Medicaid ESRD Death Notification Form. Patients were censored at death from non-CVD events, loss to follow-up, recovery, or survival to December 31, 2014. Adjusted proportional hazard models (95% CI) were fit to determine risk of CV hospitalization and mortality by age group. Data analysis occurred from May 2016 and December 2017.

Exposures

Onset of ESRD.

Main Outcomes and Measures

Cardiovascular mortality and hospitalization.

Results

A total of 33 156 patients aged 1 to 29 years were included in the study population. Young adults (aged 22-29 years) had a 1-year CV hospitalization rate of 138 (95% CI, 121-159) per 1000 patient-years. Young adults had a higher risk for CV hospitalization than children (aged 1-11 years; hazard ratio [HR], 0.41 [95% CI, 0.26-0.64]) and adolescents (aged 12-21 years; HR, 0.86 [95% CI, 0.77-0.97]). Of 4038 deaths in young adults, 1577 (39.1%) were owing to CVD. Five-year cumulative incidence of mortality in this group (7.3%) was higher than in younger patients (adolescents, 4.0%; children, 1.7%). Adjusted HRs for CV mortality were higher for young adults with all causes of ESRD than children (cystic, hereditary, and congenital conditions: HR, 0.22 [95% CI, 0.11-0.46]; P < .001; glomerulonephritis: HR, 0.21 [95% CI, 0.10-0.44]; P < .001; other conditions: HR, 0.33 [95% CI, 0.23-0.49]; P < .001). Adolescents had a lower risk for CV mortality than young adults for all causes of ESRD except glomerulonephritis (cystic, hereditary, and congenital conditions: HR, 0.45 [95% CI, 0.27-0.74]; glomerulonephritis: HR, 0.99 [95% CI, 0.76-1.11]; other: HR, 0.47 [95% CI, 0.40-0.57]). Higher risks for CV hospitalization and mortality were associated with lack of preemptive transplant compared with hemodialysis (hospital: HR, 14.24 [95% CI, 5.92-34.28]; mortality: HR, 13.64 [95% CI, 8.79-21.14]) and peritoneal dialysis [hospital: HR, 8.47 [95% CI, 3.50-20.53]; mortality: HR, 7.86 [95% CI, 4.96-12.45]). Nephrology care before ESRD was associated with lower risk for CV mortality (HR, 0.77 [95% CI, 0.70-0.85]).

Conclusions and Relevance

Cardiovascular disease accounted for nearly 40% of deaths in young adults with incident ESRD in this cohort. Identified risk factors may inform development of age-appropriate ESRD strategies to improve the CV health of this population.

Achieving equity in dialysis care and outcomes: The role of policies

Socially disadvantaged persons, including racial and ethnic minorities, individuals with low incomes, homeless persons, and non-US citizens bear a disproportionate burden of end-stage kidney disease (ESKD). Inequities in nephrology referral, vascular access, use of home dialysis modalities, kidney transplantation, and mortality are prominent. Public policies, including the Patient Protection and Affordable Care Act, end-stage renal disease Quality Incentive Program, and the Prospective Payment System, were enacted to improve healthcare access and dialysis care. Here, we highlight inequities in dialysis care and outcomes, how current ESKD and other public policies may influence or exacerbate these inequities, and gaps in the literature needed to inform future policies toward achieving equity in ESKD. We give special attention to the 2019 Advancing American Kidney Health Executive Order, which has high potential to radically transform dialysis care.

Racial/Ethnic Differences in Dialysis Discontinuation and Survival after Hospitalization for Serious Conditions among Patients on Maintenance Dialysis

BACKGROUND

Racial and ethnic minorities on dialysis survive longer than whites, and are less likely to discontinue dialysis. Both differences have been attributed by some clinicians to better health among minorities on dialysis.

METHODS

To test if racial and ethnic differences in dialysis discontinuation reflected better health, we conducted a retrospective cohort study of survival and dialysis discontinuation among patients on maintenance dialysis in the US Renal Data System after hospitalization for either stroke (n=60,734), lung cancer (n=4100), dementia (n=40,084), or failure to thrive (n=42,950) between 2003 and 2014. We examined the frequency of discontinuation of dialysis and used simulations to estimate survival in minorities relative to whites if minorities had the same pattern of dialysis discontinuation as whites.

RESULTS

Blacks, Hispanics, and Asians had substantially lower frequencies of dialysis discontinuation than whites in each hospitalization cohort. Observed risks of mortality were also lower for blacks, Hispanics, and Asians. In simulations that assigned discontinuation patterns similar to those found among whites across racial and ethnic groups, differences in survival were markedly attenuated and hazard ratios approached 1.0. Survival and dialysis discontinuation frequencies among American Indians and Alaska Natives were close to those of whites.

CONCLUSIONS

Racial and ethnic differences in dialysis discontinuation were present among patients hospitalized with similar health events. Among these patients, survival differences between racial and ethnic minorities and whites were largely attributable to differences in the frequency of discontinuation of dialysis.

Physical Symptom Cluster Subgroups in Chronic Kidney Disease

BACKGROUND

Symptom burden associated with chronic kidney disease can be debilitating, with a negative effect on patient health-related quality of life. Latent class clustering analysis is an innovative tool for classifying patient symptom experience.

OBJECTIVES

The aim of the study was to identify subgroups of patients at greatest risk for high symptom burden, which may facilitate development of patient-centered symptom management interventions.

METHODS

In this cross-sectional analysis, baseline data were analyzed from 3,921 adults enrolled in the Chronic Renal Insufficiency Cohort Study from 2003 to 2008. Latent class cluster modeling using 11 items on the Kidney Disease Quality of Life symptom profile was employed to identify patient subgroups based on similar observed physical symptom response patterns. Multinomial logistic regression models were estimated with demographic variables, lifestyle and clinical variables, and self-reported measures (Kidney Disease Quality of Life physical and mental component summaries and the Beck Depression Inventory).

RESULTS

Three symptom-based subgroups were identified, differing in severity (low symptom, moderate symptom, and high symptom). After adjusting for other variables in multinomial logistic regression, membership in the high-symptom subgroup was less likely for non-Hispanic Blacks and men. Other factors associated with membership in the high-symptom subgroup included lower estimated glomerular filtration rate, history of cardiac/cardiovascular disease, higher Beck Depression Inventory scores, and lower Kidney Disease Quality of Life physical and mental component summaries.

DISCUSSION

Three symptom subgroups of patients were identified among patients with mild-to-moderate chronic kidney disease. Several demographic and clinical variables predicted membership in subgroups. Further research is needed to determine if symptom subgroups are stable over time and can be used to predict healthcare utilization and clinical outcomes.

The Frequency of Routine Blood Sampling and Patient Outcomes Among Maintenance Hemodialysis Recipients

RATIONALE & OBJECTIVE

Surveillance blood work is routinely performed in maintenance hemodialysis (HD) recipients. Although more frequent blood testing may confer better outcomes, there is little evidence to support any particular monitoring interval.

STUDY DESIGN

Retrospective population-based cohort study.

SETTING & PARTICIPANTS

All prevalent HD recipients in Ontario, Canada, as of April 1, 2011, and a cohort of incident patients commencing maintenance HD in Ontario, Canada, between April 1, 2011, and March 31, 2016.

EXPOSURE

Frequency of surveillance blood work, monthly versus every 6 weeks.

OUTCOMES

The primary outcome was all-cause mortality. Secondary outcomes were major adverse cardiovascular events, all-cause hospitalization, and episodes of hyperkalemia.

ANALYTICAL APPROACH

Cox proportional hazards with adjustment for demographic and clinical characteristics was used to evaluate the association between blood testing frequency and all-cause mortality. Secondary outcomes were evaluated using the Andersen-Gill extension of the Cox model to allow for potential recurrent events.

RESULTS

7,454 prevalent patients received care at 17 HD programs with monthly blood sampling protocols (n=5,335 patients) and at 8 programs with blood sampling every 6 weeks (n=2,119 patients). More frequent monitoring was not associated with a lower risk for all-cause mortality compared to blood sampling every 6 weeks (adjusted HR, 1.16; 95% CI, 0.99-1.38). Monthly monitoring was not associated with a lower risk for any of the secondary outcomes. Results were consistent among incident HD recipients.

LIMITATIONS

Unmeasured confounding; limited data for center practices unrelated to blood sampling frequency; no information on frequency of unscheduled blood work performed outside the prescribed sampling interval.

CONCLUSIONS

Monthly routine blood testing in HD recipients was not associated with a lower risk for death, cardiovascular events, or hospitalizations as compared with testing every 6 weeks. Given the health resource implications, the frequency of routine blood sampling in HD recipients deserves careful reassessment.

The Impact of Race and Ethnicity Upon Health-Related Quality of Life and Mortality in Dialysis Patients

Rationale & Objective

Health-related quality of life (HRQoL) has been recognized as a strong predictor of mortality among hemodialysis patients. However, differences in the association of HRQoL with survival across diverse racial/ethnic groups have not been well studied in this population.

Study Design

Observational cohort study.

Setting & Participants

We examined the relationship between HRQoL and mortality in a prospective cohort of racially/ethnically diverse hemodialysis patients recruited from 18 outpatient dialysis units during 2011 to 2016.

Exposure

Using the 36-Item Short Form Health Survey (SF-36) administered every 6 months, HRQoL was ascertained by 36 questions summarized as 2 Physical and Mental Component and 8 subscale scores.

Outcome

All-cause mortality.

Analytical Approach

Associations of time-varying SF-36 scores with mortality were estimated using Cox models in the overall cohort and within racial/ethnic subgroups.

Results

Among 753 hemodialysis patients who met eligibility criteria, expanded case-mix analyses showed that the lowest quartiles of time-varying Physical and Mental Component scores were associated with higher mortality in the overall cohort (reference: highest quartile): adjusted HRs, 2.30 (95% CI, 1.53-3.47) and 1.54 (95% CI, 1.05-2.25), respectively. In analyses stratified by race/ethnicity, the lowest quartile of Physical Component scores was significantly associated with higher mortality across all groups: adjusted HRs, 2.64 (95% CI, 1.31-5.29), 1.84 (95% CI, 1.01-3.38), and 3.18 (95% CI, 1.13-8.91) for Hispanic, African American, and other race/ethnicity patients, respectively. The lowest quartile of time-varying physical functioning, role limitations due to physical health, role limitations due to emotional problems, social functioning, and pain subscale scores were associated with higher mortality in the overall cohort and particularly in Hispanics and blacks.

Limitations

Residual confounding cannot be excluded.

Conclusions

Lower SF-36 Physical Component and subscale scores were associated with higher mortality in hemodialysis patients, including those of minority background. Further studies are needed to determine whether interventions that augment physical health might improve the survival of these diverse populations.

The association of neighborhood racial mix and ED visit count in a cohort of patients on hemodialysis

Background

Neighborhood racial mix is associated with dialysis facility performance metrics and mortality outcomes in patients on hemodialysis. We explored the association of neighborhood racial mix with emergency department (ED) visits in patients receiving hemodialysis.

Methods

Using Looking Glass (Montefiore’s clinical database) we identified a cohort of patients on hemodialysis with an index ED visit at any of 4 Montefiore Hospital locations, between January 2013 and December 2017 and followed it for number of ED visits through December of 2017 or dropout due to death. The racial mix data for the Bronx block group of each subject’s residence was derived from the Census Bureau. We then used negative binomial regression to test the association of quintile of percent of Black residents per residential block group with ED visits in unadjusted and adjusted models. To adjust further for quality offered by local dialysis facilities, with the facility zip code as the locus, we used data from the “Dialysis Compare” website.

Results

Three thousand nine-hundred and eighteen subjects were identified and the median number of ED visits was 3 (interquartile range (IQR) 1–7) during the study period. Subjects living in the highest quintile of percent Black residents were older, more commonly female and had lower poverty rates and higher rates of high school diplomas. Unadjusted models showed a significant association between the highest quintiles of Black neighborhood residence and count of ED visits. Fully adjusted, stratified models revealed that among males, and Hispanic and White subjects, living in neighborhoods with the highest quintiles of Black residents was associated with significantly more ED visits (p-trend =0.001, 0.02, 0.01 respectively). No association was found between dialysis facility locations’ quintile of Black residents and quality metrics.

Conclusions

Living in a neighborhood with a higher percentage of Black residents is associated with a higher number of ED visits in males and non-Black patients on hemodialysis.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1520-x) contains supplementary material, which is available to authorized users.

Use of Percutaneous Coronary Intervention Among Black and White Patients With End-Stage Renal Disease in the United States

Background Racial disparities in invasive cardiac procedures such as percutaneous coronary intervention (PCI) in the general population are well documented; however, national-level data on such disparities in the end-stage renal disease (ESRD) population are lacking. We assessed racial differences in PCI between black and white patients with ESRD on maintenance dialysis. Methods and Results Using the US Renal Data System database, we abstracted Medicare inpatient procedure claims for PCI in a cohort of 268 575 Medicare-primary patients who initiated treatment on maintenance dialysis from January 1, 2009, through June 1, 2013. We conducted Cox regression analyses with PCI being the event, adjusted for demographic characteristics, Hispanic ethnicity, cause of ESRD, comorbidities, and socioeconomic factors. We also assessed the probability of PCI, accounting for death or transplant in competing risk regression models. The crude incidence rate of PCI among white patients was 25.8 per 1000 patient-years versus 15.5 per 1000 patient-years among black patients. Cox regression analyses demonstrated that black patients were significantly less likely to undergo PCI compared with white patients (adjusted hazard ratio: 0.64; 95% CI, 0.62-0.67; P<0.001). In the competing risk models, the racial gap for PCI among black and white patients remained significant with death (subdistribution hazard ratio: 0.81; 95% CI, 0.76-0.85; P<0.001) or transplant as a competing event (subdistribution hazard ratio: 0.67; 95% CI, 0.64-0.70; P<0.001). Conclusions A racial gap exists in PCI use among dialysis patients despite having comprehensive coverage with Medicare. These findings persisted despite accounting for demographic, clinical, socioeconomic factors, and death or transplant as competing events.

Association of Race and Poverty With Mortality Among Nursing Home Residents on Maintenance Dialysis

OBJECTIVES

The association of race, ethnicity, and socioeconomic factors with survival rates of nursing home (NH) residents with treated end-stage renal disease (ESRD) is unclear. We examined whether race/ethnicity, ZIP code-level, and individual-level indicators of poverty relate to mortality of NH residents on dialysis.

DESIGN

Retrospective cohort study.

PARTICIPANTS/SETTING

Using the United States Renal Data System database, we identified 56,194 nursing home residents initiated on maintenance dialysis from January 1, 2007 through December 31, 2013, followed until May 31, 2014.

MEASUREMENTS

We evaluated baseline characteristics of the NH cohort on dialysis, including race and ethnicity. We assessed the Medicare-Medicaid dual eligibility status as an indicator of individual-level poverty and ZIP code-level median household income (MHI) data. We conducted Cox regression analyses with all-cause mortality as the outcome variable, adjusted for clinical and sociodemographic factors including end-of-life preferences.

RESULTS

Adjusted Cox analysis showed a significantly lower risk of death among black vs nonblack NH residents [adjusted hazard ratio (AHR) 0.91, 95% confidence interval (CI) 0.89, 0.94]. Dual-eligibility status was significantly associated with lower risk of death compared to those with Medicare alone (AHR 0.80, 95% CI 0.78, 0.82). Compared to those in higher MHI quintile levels, NH ESRD patients in the lowest quintile were significantly associated with higher risk of death (AHR 1.09, 95% CI 1.06, 1.13).

CONCLUSIONS/IMPLICATIONS

Black and Hispanic NH residents on dialysis had an apparent survival advantage. This "survival paradox" occurs despite well-documented racial/ethnic disparities in ESRD and NH care and warrants further exploration that could generate new insights into means of improving survival of all NH residents on dialysis. Area-level indicator of poverty was independently associated with mortality, whereas dual-eligibility status for Medicare and Medicaid was associated with lower risk of death, which could be partly explained by improved access to care.

Inequalities and outcomes: end stage kidney disease in ethnic minorities

Background

The international evidence about outcomes of End Stage Kidney Disease (ESKD) for ethnic minorities was reviewed to identify gaps and make recommendations for researchers and policy makers.

Methods

Nine databases were searched systematically with 112 studies from 14 different countries included and analysed to produce a thematic map of the literature.

Results

Reviews (n = 26) highlighted different mortality rates and specific causes between ethnic groups and by stage of kidney disease associated with individual, genetic, social and environmental factors. Primary studies focussing on uptake of treatment modalities (n = 19) found ethnic differences in access. Research evaluating intermediate outcomes and quality of care in different treatment phases (n = 35) e.g. dialysis adequacy, transplant evaluation and immunosuppression showed ethnic minorities were disadvantaged. This is despite a survival paradox for some ethnic minorities on dialysis seen in studies of longer term outcomes (n = 29) e.g. in survival time post-transplant and mortality. There were few studies which focussed on end of life care (n = 3) and ethnicity.

Gaps identified were: limited evidence from all stages of the ESKD pathway, particularly end of life care; a lack of system oriented studies with a reliance on national routine datasets which are limited in scope; a dearth of qualitative studies; and a lack studies from many countries with limited cross country comparison and learning.

Conclusions

Differences between ethnic groups occur at various points and in a variety of outcomes throughout the kidney care system. The combination of individual factors and system related variables affect ethnic groups differently indicating a need for culturally intelligent policy informed by research to prevent disadvantage.

Survival Advantage of African American Dialysis Patients with End-Stage Renal Disease Causes Related to APOL1

BACKGROUND

Observational studies show that African American (AA) dialysis patients have longer survival than European Americans. We hypothesized that apolipoprotein L1 (APOL1) genetic variation, associated with nephropathy in AAs, contributes to the survival advantage in AA dialysis patients.

METHODS

We examined the association between race and mortality among 37,097 adult dialysis patients, including 54% AAs and 46% European Americans from a large dialysis organization (entry period from July 2001 to June 2006, follow-up through June 2007), within each cause of end-stage renal disease (ESRD) category associated with APOL1 renal risk variants using Cox proportional hazard models.

RESULTS

AA dialysis patients had numerically lower mortality than their European American counterparts for all causes of ESRD. The mortality reduction among AAs compared to European Americans was statistically significant in patients with ESRD attributed to diabetes mellitus, hypertension, and APOL1-enriched glomerulonephritis (GN) (HR [95% CI]: 0.69 [0.66-0.72], 0.73 [0.68-0.79], and 0.89 [0.79-0.99], respectively); these are conditions in which APOL1 variants promote kidney disease. By contrast, the significant survival advantage of AA dialysis patients was not observed in patients with ESRD attributed to other kidney disease (including polycystic kidney disease, interstitial nephritis, and pyelonephritis) and other GN, which are not associated with APOL1 variants.

CONCLUSIONS

These data suggest the hypothesis that the relative survival advantage of AA dialysis patients may be related to APOL1 variation. Further large population-based genetic studies are required to test this hypothesis.

The TiME Trial: A Fully Embedded, Cluster-Randomized, Pragmatic Trial of Hemodialysis Session Duration

BACKGROUND

Data from clinical trials to inform practice in maintenance hemodialysis are limited. Incorporating randomized trials into dialysis clinical care delivery should help generate practice-guiding evidence, but the feasibility of this approach has not been established.

METHODS

To develop approaches for embedding trials into routine delivery of maintenance hemodialysis, we performed a cluster-randomized, pragmatic trial demonstration project, the Time to Reduce Mortality in ESRD (TiME) trial, evaluating effects of session duration on mortality (primary outcome) and hospitalization rate. Dialysis facilities randomized to the intervention adopted a default session duration ≥4.25 hours (255 minutes) for incident patients; those randomized to usual care had no trial-driven approach to session duration. Implementation was highly centralized, with no on-site research personnel and complete reliance on clinically acquired data. We used multiple strategies to engage facility personnel and participating patients.

RESULTS

The trial enrolled 7035 incident patients from 266 dialysis units. We discontinued the trial at a median follow-up of 1.1 years because of an inadequate between-group difference in session duration. For the primary analysis population (participants with estimated body water ≤42.5 L), mean session duration was 216 minutes for the intervention group and 207 minutes for the usual care group. We found no reduction in mortality or hospitalization rate for the intervention versus usual care.

CONCLUSIONS

Although a highly pragmatic design allowed efficient enrollment, data acquisition, and monitoring, intervention uptake was insufficient to determine whether longer hemodialysis sessions improve outcomes. More effective strategies for engaging clinical personnel and patients are likely required to evaluate clinical trial interventions that are fully embedded in care delivery.

Trimethylamine N-Oxide and Cardiovascular Outcomes in Patients with ESKD Receiving Maintenance Hemodialysis

BACKGROUND AND OBJECTIVES

Trimethylamine N-oxide (TMAO), a compound derived from byproducts of intestinal bacteria, has been shown to accelerate atherosclerosis in rodents. To date, there are conflicting data regarding the association of serum TMAO with cardiovascular outcomes in patients with ESKD, a population exhibiting both high serum TMAO and excessive atherosclerosis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We measured baseline serum TMAO concentrations in a subset of participants (n=1243) from the Evaluation of Cinacalcet Hydrochloride Therapy to Lower Cardiovascular Events (EVOLVE) trial and conducted post hoc analyses evaluating the association between baseline serum TMAO and cardiovascular outcomes.

RESULTS

We observed a wide distribution of serum TMAO in our cohort, with approximately 80% of participants exhibiting TMAO concentrations ≥56 µM and a maximum TMAO concentration of 1103.1 µM. We found no association between TMAO and our primary outcome, a composite of cardiovascular mortality, myocardial infarction, peripheral vascular event, stroke, and hospitalization for unstable angina. Moreover, in unadjusted and adjusted analyses, we observed no relation between TMAO and all-cause mortality, the independent components of our composite outcome, or the original EVOLVE primary outcome. Although we did observe higher TMAO concentrations in white participants, further subgroup analyses did not confirm the previously identified interaction between TMAO and race observed in a prior study in patients receiving dialysis.

CONCLUSIONS

We found no evidence linking TMAO to adverse clinical outcomes in patients receiving maintenance hemodialysis with moderate to severe secondary hyperparathyroidism.

Gender and Racial Disparities in Initial Hemodialysis Access and Outcomes in Incident End-Stage Renal Disease Patients

BACKGROUND

Arteriovenous (AV) access confers survival benefits over central venous catheters (CVC) in hemodialysis patients. Although chronic kidney disease disproportionately affects women and racial minorities, disparities in the -utilization of hemodialysis access across Asians, Native Americans, Hispanics, blacks, and whites among males and females after accounting for pre-dialysis health are not well studied.

METHODS

We evaluated 885,699 patients with end-stage renal disease who initiated hemodialysis between January 1, 2004 and December 31, 2014 using the US Renal Data System. Multivariable logistic regression models -adjusted for pre-dialysis health were used to test the associations between gender and race on type of vascular access (AV access vs. CVC, and AV fistula vs. AV graft) at hemodialysis initiation as primary outcome, and on 1-year mortality as a secondary outcome.

RESULTS

Mean age was 65 ± 14 years. Females were less likely to use AV access for hemodialysis initiation than were males (OR 0.85; 95% CI 0.84-0.86). Compared to whites, adjusted odds of AV access for hemodialysis initiation were higher in blacks (OR 1.08; 95% CI 1.07-1.70), Asians (OR 1.11; 95% CI 1.07-1.14); and lower in Hispanics (OR 0.89; 95% CI 0.87-0.90). There was no -significant difference in mortality between males and females. Compared to whites, 1-year adjusted mortality was lower in Asians (OR 0.55; 95% CI 0.53-0.56), blacks (OR 0.67; 95% CI 0.66-0.68), Hispanics (OR 0.62; 95% CI 0.61-0.63), and Native Americans (OR 0.62; 95% CI 0.58-0.66).

CONCLUSION

Females had lower odds of using AV access than do males for hemodialysis initiation. As compared to whites, blacks and Asians were more likely, and Hispanics were less likely to use AV access for first outpatient hemodialysis. Further investigation of biological and process of care factors may help in developing ways to reduce these disparities.

Machine Learning to Compare Frequent Medical Problems of African American and Caucasian Diabetic Kidney Patients

Objectives

End-stage renal disease (ESRD), which is primarily a consequence of diabetes mellitus, shows an exemplary health disparity between African American and Caucasian patients in the United States. Because diabetic chronic kidney disease (CKD) patients of these two groups show differences in their medical problems, the markers leading to ESRD are also expected to differ. The purpose of this study was, therefore, to compare their medical complications at various levels of kidney function and to identify markers that can be used to predict ESRD.

Methods

The data of type 2 diabetic patients was obtained from the 2012 Cerner database, which totaled 1,038,499 records. The data was then filtered to include only African American and Caucasian outpatients with estimated glomerular filtration rates (eGFR), leaving 4,623 records. A priori machine learning was used to discover frequently appearing medical problems within the filtered data. CKD is defined as abnormalities of kidney structure, present for >3 months.

Results

This study found that African Americans have much higher rates of CKD-related medical problems than Caucasians for all five stages, and prominent markers leading to ESRD were discovered only for the African American group. These markers are high glucose, high systolic blood pressure (BP), obesity, alcohol/drug use, and low hematocrit. Additionally, the roles of systolic BP and diastolic BP vary depending on the CKD stage.

Conclusions

This research discovered frequently appearing medical problems across five stages of CKD and further showed that many of the markers reported in previous studies are more applicable to African American patients than Caucasian patients.

Current State and Future Trends to Optimize the Care of African Americans with End-Stage Renal Disease

BACKGROUND

Chronic kidney disease is a progressive disease, which terminates in end-stage renal diseases (ESRD) that requires either dialysis or kidney transplantation for the patient to survive. There is an alarming trend in the disparities of ESRD in African Americans (AAs). Currently, AAs represent more than 30% of incident ESRD cases, yet they constitute 15% of the overall US population. Despite the reductions in mortality, increases in access to patient-centered home dialysis and preemptive kidney transplantation for the overall US ESRD population over the last decade, disparities in the care of AAs with ESRD remain largely unaffected.

SUMMARY

This review discusses patient-, community-, and practitioner-related factors that contribute to disparities in ESRD care for AAs. In particular, the review addresses issues related to end-of-life support, the importance of Apolipoprotein-1 gene variants, and the advent of pharmacogenomics toward achieving precision care. The need for accessible clinical intelligence for the ESRD population is discussed. Several interventions and a call to action to address the disparities are presented. Key Messages: Significant disparities in ESRD care exist for AAs. Strategies to enhance patient engagement, education, accountable partnerships, and clinical intelligence may reduce these disparities.

Level of inflammatory factors in chronic hemodialysis patients with and without cardiovascular disease

Background:

Considering the existence of controversies about the predictive value of inflammatory markers for cardiovascular disease (CVD), we aimed to compare the level of high-sensitivity C-reactive protein (hs-CRP) and interlukin-6 (IL-6) level in chronic hemodialysis (HD) patients with and without CVD.

Materials and Methods:

In this historical cohort study, HD patients with and without CVD disease were enrolled. The presence of CVD risk factors, level of inflammatory factors including IL-6 and hs-CRP as well as lipid levels, fasting blood sugar, and other biochemical factors were compared in two studied groups.

Results:

During the study, eighty HD patients with (n = 40) and without (n = 40) CVD were enrolled. Diabetes was more prevalent among HD patients with CVD than those without CVD (P < 0.05). The level of IL-6 and hs-CRP were not different in two studied groups (P > 0.05). Univariate analysis of variance test indicated that there was not any significant relationship between hs-CRP and CVD (P > 0.05).

Conclusion:

The findings indicated that the level of inflammatory factors including hs-CRP and IL-6 are not significantly different in HD patients with and without CVD. However, for obtaining more definite conclusion in this field and evaluation their predicting role in this field, it is recommended to study other novel inflammatory markers as well as the additive effect of the inflammatory factors with traditional ones in larger sample size and longer follow-up.

Younger black patients have a higher risk of infection mortality that is mostly non-dialysis related: A national study of cause-specific mortality among U.S. maintenance dialysis patients

INTRODUCTION

While it has been well documented that in the U.S., black and Hispanic dialysis patients have overall lower risks of death than white dialysis patients, little is known whether their lower risks are observed in cause-specific deaths. Additionally, recent research reported that younger black patients have a higher risk of death, but the source is unclear. Therefore, this study examined cause-specific deaths among US dialysis patients by race/ethnicity and age.

METHODS

This national study included 1,255,640 incident dialysis patients between 1995 and 2010 in the United States Renal Data System. Five cause-specific mortality rates, including cardiovascular (CVD), infection, malignancy, other known causes (miscellaneous), and unknown, were compared across blacks, Hispanics, and whites overall and stratified by age groups.

FINDINGS

After multiple adjustments, Hispanic patients had the lowest risk of mortality for every major cause in almost all ages. Compared with whites, blacks had a lower risk of death from CVD, malignancy and miscellaneous causes in most age groups, but not from infection. In fact, blacks had a higher risk of infection death than whites in ages 18-30 years (HR [95% CI] 1.94 [1.69-2.23]; P < 0.001), 31-40 years (HR 1.51 [1.40-1.63]; P < 0.001) and 41-50 years (HR 1.07 [1.02-1.12]; P = 0.009), which were partially attributed to their higher prevalence of AIDS nephropathy. For each race/ethnicity, more than two-thirds of infection deaths were due to non-dialysis related infections.

DISCUSSION

Hispanics had the lowest risk for each major cause of death. Blacks were less likely to die than whites from most causes, except infection. The previously reported higher overall mortality rate for younger blacks is attributed to their two-fold higher infection mortality, which is mostly non-dialysis related, suggesting a new direction to improve their overall health status. Research is greatly needed to determine social and biological factors that account for the survival gap in dialysis among different racial/ethnic groups.

Impact of residual urine volume decline on the survival of chronic hemodialysis patients in Kinshasa

Background

Despite the multiple benefits of maintaining residual urine volume (RUV) in hemodialysis (HD), there is limited data from Sub-Saharan Africa. The aim of this study was to assess the impact of RUV decline on the survival of HD patients.

Methods

In a retrospective cohort study, 250 consecutive chronic HD patients (mean age 52.5 years; 68.8% male, median HD duration 6 months) from two hospitals in the city of Kinshasa were studied, between January 2007 and July 2013. The primary outcome was lost RUV. Preserved or lost RUV was defined as decline RUV < 25 (median decline) or ≥ 25 ml/day/month, respectively. The second endpoint was survival (time-to death). Survival curves were built using the Kaplan-Meier methods. We used Log-rank test to compare survival curves. Predictors of mortality were assessed by Cox proportional hazards regression models.

Results

The cumulative incidence of patients with RUV decline was 52, 4%. The median (IQR) decline in RUV was 25 (20.8–33.3) ml/day/month in the population studied, 56.7 (43.3–116.7) in patients deceased versus 12.9 (8.3–16.7) in survivor patients (p < 0.001). Overall mortality was 78 per 1000 patient years (17 per 1000 in preserved vs 61 per 1000 lost RUV). Forty six patients (18.4%) died from withdrawal of HD due to financial constraints. The Median survival was 17 months in the whole group while, a significant difference was shown between lost (10 months, n = 119) vs preserved RUV group (30 months, n = 131; p = 0001). Multivariate Cox proportional hazards models showed that, decreased RUV (adjusted HR 5.35, 95% CI [2.73–10.51], p < 0.001), financial status (aHR 2.23, [1.11–4.46], p = 0.024), hypervolemia (a HR 2.00, [1.17–3.40], p = 0.011), lacking ACEI (aHR 2.48, [1.40–4.40], p = 0.002) or beta blocker use (aHR 4.04, [1.42–11.54], p = 0.009), central venous catheter (aHR 6.26, [1.71–22.95], p = 0.006), serum albumin (aHR 0.93, [0.89–0.96], p < 0.001) and hemoglobin (aHR 0.73, [0.63–0.84], p < 0.001) had emerged as the independent predictors of all-cause mortality.

Conclusion

More than half of HD patients in this cohort study experienced fast RUV decline which contributed substantially to increase mortality, highlighting the need for its prevention and management.

Risk of ESRD in the United States

BACKGROUND

Although incidence rates of end-stage renal disease (ESRD) in the United States are reported routinely by the US Renal Data System (USRDS), risks (probabilities) are not reported. Short- and long-term risk estimates need to be updated and expanded to minority populations, including Native Americans, Asian/Pacific Islanders, and Hispanics.

STUDY DESIGN

Risk estimation from surveillance data in large populations using life-table methods. A competing-risks framework was applied by constructing a hypothetical cohort followed from birth to death.

SETTING & PARTICIPANTS

Total US population. Incidence and mortality rates of ESRD were obtained from the USRDS; all-cause mortality rates were obtained from CDC WONDER.

PREDICTORS

Age, sex, race/ethnicity, and year.

OUTCOMES

10-year to lifetime risks (cumulative incidence) of ESRD.

RESULTS

Among males, lifetime risks of ESRD from birth using 2013 data were 3.1% (95% CI, 3.0%-3.1%) for non-Hispanic whites, 8.0% (95% CI, 7.9%-8.2%) for non-Hispanic blacks, 3.8% (95% CI, 3.4%-4.9%) for non-Hispanic Native Americans, 5.1% (95% CI, 4.8%-5.4%) for non-Hispanic Asians/Pacific Islanders, and 6.2% (95% CI, 6.1%-6.4%) for Hispanics. Among females, lifetime risks were 2.0% (95% CI, 2.0%-2.1%) for non-Hispanic whites, 6.8% (95% CI, 6.7%-6.9%) for non-Hispanic blacks, 3.6% (95% CI, 3.3%-4.2%) for non-Hispanic Native Americans, 3.8% (95% CI, 3.6%-4.0%) for non-Hispanic Asian/Pacific Islanders, and 4.3% (95% CI, 4.2%-4.5%) for Hispanics. Lifetime risk of ESRD from birth increased from 3.5% in 2000 to 4.0% in 2013 in males and decreased from 3.0% to 2.8% in females.

LIMITATIONS

Standard life-time assumption of fixed age-specific rates over time and possible ESRD misclassification. To be useful in clinical practice, this application will require additional predictors (eg, comorbid conditions and chronic kidney disease stage).

CONCLUSIONS

ESRD risk in the United States varies more than 2-fold among racial/ethnic groups for both sexes.

Trimethylamine N-Oxide and Cardiovascular Events in Hemodialysis Patients

Cardiovascular disease causes over 50% of the deaths in dialysis patients, and the risk of death is higher in white than in black patients. The underlying mechanisms for these findings are unknown. We determined the association of the proatherogenic metabolite trimethylamine N-oxide (TMAO) with cardiovascular outcomes in hemodialysis patients and assessed whether this association differs by race. We measured TMAO in stored serum samples obtained 3-6 months after randomization from a total of 1232 white and black patients of the Hemodialysis Study, and analyzed the association of TMAO with cardiovascular outcomes using Cox models adjusted for potential confounders (demographics, clinical characteristics, comorbidities, albumin, and residual kidney function). Mean age of the patients was 58 years; 35% of patients were white. TMAO concentration did not differ between whites and blacks. In whites, 2-fold higher TMAO associated with higher risk (hazard ratio [95% confidence interval]) of cardiac death (1.45 [1.24 to 1.69]), sudden cardiac death [1.70 (1.34 to 2.15)], first cardiovascular event (1.15 [1.01 to 1.32]), and any-cause death (1.22 [1.09 to 1.36]). In blacks, the association was nonlinear and significant only for cardiac death among patients with TMAO concentrations below the median (1.58 [1.03 to 2.44]). Compared with blacks in the same quintile, whites in the highest quintile for TMAO (≥135 μM) had a 4-fold higher risk of cardiac or sudden cardiac death and a 2-fold higher risk of any-cause death. We conclude that TMAO concentration associates with cardiovascular events in hemodialysis patients but the effects differ by race.

Increased risk of atrial fibrillation in end-stage renal disease patients on dialysis: A nationwide, population-based study in Taiwan

End-stage renal disease (ESRD) patients commonly have a higher risk of developing cardiovascular diseases than general population. Chronic kidney disease is an independent risk factor for atrial fibrillation (AF); however, little is known about the AF risk among ESRD patients with various modalities of renal replacement therapy. We used the Taiwan National Health Insurance Research Database to determine the incident AF among peritoneal dialysis (PD) and hemodialysis (HD) patients in Taiwan.Our ESRD cohort include Taiwan National Health Insurance Research Database, we identified 15,947 patients, who started renal replacement therapy between January 1, 2002 and December 31, 2003. From the same data source, 47,841 controls without ESRD (3 subjects for each patient) were identified randomly and frequency matched by gender, age (±1 year), and the year of the study patient's index date for ESRD between January 1, 2002 and December 31, 2003.During the follow-up period (mean duration: 8-10 years), 3428 individuals developed the new-onset AF. The incidence rate ratios for AF were 2.07 (95% confidence interval [CI] = 1.93-2.23) and 1.78 (95% CI = 1.30-2.44) in HD and PD groups, respectively. After we adjusted for age, gender, and comorbidities, the hazard ratios for the AF risk were 1.46 (95% CI = 1.32-1.61) and 1.32 (95% CI = 1.00-1.83) in HD and PD groups, respectively. ESRD patients with a history of certain comorbidities including hypertension, diabetes mellitus, hyperlipidemia, coronary artery disease, heart failure, valvular heart disease, and chronic obstructive pulmonary disease (COPD) have significantly increased risks of AF.This nationwide, population-based study suggests that incidence of AF is increased among dialysis ESRD patients. Furthermore, we have to pay more attention in clinical practice and long-term care for those ESRD patients with a history of certain comorbidities.

Racial and Ethnic Differences in Mortality and Cardiovascular Events Among Patients With End-Stage Renal Disease Due to Lupus Nephritis

OBJECTIVE

To identify racial and ethnic differences in mortality and cardiovascular (CV) risk among patients with end-stage renal disease (ESRD) due to lupus nephritis (LN).

METHODS

Within the US ESRD registry (1995-2008), we identified individuals ages >17 years with incident ESRD due to systemic lupus erythematosus. We ascertained demographics, clinical factors, and deaths from registry patient files and CV events (myocardial infarction, heart failure, and hemorrhagic and ischemic strokes) from inpatient Medicare claims. We calculated incidence rates (95% confidence intervals [95% CIs]) per 1,000 person-years for study events, stratified by race and ethnicity. We compared probabilities of the events among racial and ethnic groups using cumulative incidence function curves and multivariable-adjusted subdistribution proportional hazard ratios (HRsd), taking into account the competing events of kidney transplantation and death (for nonfatal CV events).

RESULTS

Of 12,533 patients with LN-associated ESRD, the mean ± SD age was 40.7 ± 14.9 years, 82% were women, and 49% were African American. The overall mortality rate was 98.1/1,000 person-years (95% CI 95.3-100.9). In multivariable models, Asian and Hispanic LN-associated ESRD patients had lower mortality than whites (HRsd 0.70 [95% CI 0.58-0.84] and 0.79 [95% CI 0.71-0.88], respectively), whereas African Americans had higher mortality (HRsd 1.27 [95% CI 1.18-1.36]). African American patients >40 years old had higher mortality than their white counterparts (HRsd 1.67 [95% CI 1.44-1.93]). African Americans were more likely to be admitted for heart failure or hemorrhagic stroke.

CONCLUSION

Among patients with LN-associated ESRD, Asians and Hispanics experienced lower mortality and CV event risks than whites, and African Americans had higher mortality and CV event risks than whites.

Comorbidity burden at dialysis initiation and mortality: A cohort study

Background

A high level of comorbidity at dialysis initiation is associated with an increased risk of death. However, contemporary assessments of the validity and prognostic value of comorbidity indices are lacking.

Objectives

To assess the validity of two comorbidity indices and to determine if a high degree of comorbidity is associated with mortality among dialysis patients.

Design

Cohort study.

Setting

QEII Health Sciences Centre (Halifax, Nova Scotia, Canada).

Patients

Incident, chronic dialysis patients between 01 Jan 2006 and 01 Jul 2013.

Measurements

Exposure: The Charlson Comorbidity Index (CCI) and End-Stage Renal Disease Comorbidity Index (ESRD-CI) were used to classify individual comorbid conditions into an overall score. Comorbidities were classified using patient charts and electronic records.

Outcome: All-cause mortality.

Confounders: Patient demographics, dialysis access, cause of ESRD and baseline laboratory data.

Methods

Regression coefficients were estimated on the CCI and ESRD-CI. Discrimination for death was assessed using Harrell’s c-index. Adjusted Cox proportional hazard models were used to calculate relative hazards and 95 % confidence intervals for each category of the CCI and ESRD-CI.

Results

The cohort consisted of 771 ESRD patients from 01 Jan 2006 to 01 Jul 2013. Most were male (62 %) and Caucasian (91 %). The cohort had a high proportion of diabetes (48 %), history of previous myocardial infarction (31 %) and heart failure (22 %). Regression coefficients on the CCI and ESRD-CI were 0.55 and 0.52, respectively. The c-index, for the prediction of death, was 0.61 for the CCI and 0.63 for the ESRD-CI. ESRD-CI scores of 4, 5 and ≥6 were associated with a similar mortality risk (adjusted relative hazard of 1.95, 1.89 and 1.99, respectively). There was a small increased mortality risk for CCI scores of 4, 5 and ≥6 (adjusted relative hazard of 1.86, 2.38 and 2.71, respectively).

Limitations

Classification of comorbidities for each patient was determined by clinical impression.

Conclusions

The CCI and ESRD-CI have a limited ability to discriminate mortality risk for incident dialysis patients. Acknowledging the frequency with which they are used, this study emphasizes the need to re-examine the usefulness of previously derived comorbidity indices in contemporary dialysis cohorts.

Survival Disparity of African American Versus Non-African American Patients With ESRD Due to SLE

BACKGROUND

A recent study showed an increased risk of death in African Americans compared with whites with end-stage renal disease (ESRD) due to lupus nephritis (LN). We assessed the impact of age stratification, socioeconomic factors, and kidney transplantation on the disparity in patient survival among African American versus non-African American patients with LN-caused ESRD, compared with other causes.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Using the US Renal Data System database, we identified 12,352 patients with LN-caused ESRD among 1,132,202 patients who initiated maintenance dialysis therapy from January 1, 1995, through December 31, 2006, and were followed up until December 31, 2010.

PREDICTORS

Baseline demographics and comorbid conditions, Hispanic ethnicity, socioeconomic factors (employment status, Medicare/Medicaid insurance, and area-level median household income based on zip code as obtained from the 2000 US census), and kidney transplantation as a time-dependent variable.

OUTCOME

All-cause mortality.

MEASUREMENTS

Multivariable Cox and competing-risk regressions.

RESULTS

Mean duration of follow-up in the LN-caused ESRD and other-cause ESRD cohorts were 6.24±4.20 (SD) and 4.06±3.61 years, respectively. 6,106 patients with LN-caused ESRD (49.43%) and 853,762 patients with other-cause ESRD (76.24%) died during the study period (P<0.001). Patients with LN-caused ESRD were significantly younger (mean age, 39.92 years) and more likely women (81.65%) and African American (48.13%) than those with other-cause ESRD. In the fully adjusted multivariable Cox regression model, African American (vs non-African American) patients with LN-caused ESRD had significantly increased risk of death at age 18 to 30 years (adjusted HR, 1.43; 95% CI, 1.24-1.65) and at age 31 to 40 years (adjusted HR, 1.17; 95% CI, 1.02-1.34). Among patients with other-cause ESRD, African Americans were at significantly increased risk at age 18 to 30 years (adjusted HR, 1.17; 95% CI, 1.11-1.22).

LIMITATIONS

We used zip code-based median household income as a surrogate for patient income. Residual socioeconomic confounders may exist.

CONCLUSIONS

African Americans are at significantly increased risk of death compared with non-African Americans with LN-caused ESRD at age 18 to 40 years, a racial disparity risk that is 10 years longer than that in the general ESRD population. Accounting for area-level median household income and transplantation significantly attenuated the disparity in mortality of African American versus non-African American patients with LN-caused ESRD.

Neighborhood socioeconomic status, race, and mortality in young adult dialysis patients

Young blacks receiving dialysis have an increased risk of death compared with whites in the United States. Factors influencing this disparity among the young adult dialysis population have not been well explored. Our study examined the relation of neighborhood socioeconomic status (SES) and racial differences in mortality in United States young adults receiving dialysis. We merged US Renal Data System patient-level data from 11,027 black and white patients ages 18-30 years old initiating dialysis between 2006 and 2009 with US Census data to obtain neighborhood poverty information for each patient. We defined low SES neighborhoods as those neighborhoods in U.S. Census zip codes with ≥20% of residents living below the federal poverty level and quantified race differences in mortality risk by level of neighborhood SES. Among patients residing in low SES neighborhoods, blacks had greater mortality than whites after adjusting for baseline demographics, clinical characteristics, rurality, and access to care factors. This difference in mortality between blacks and whites was significantly attenuated in higher SES neighborhoods. In the United States, survival between young adult blacks and whites receiving dialysis differs by neighborhood SES. Additional studies are needed to identify modifiable factors contributing to the greater mortality among young adult black dialysis patients residing in low SES neighborhoods.

The RaDIANT community study protocol: community-based participatory research for reducing disparities in access to kidney transplantation

BACKGROUND

The Southeastern United States has the lowest kidney transplant rates in the nation, and racial disparities in kidney transplant access are concentrated in this region. The Southeastern Kidney Transplant Coalition (SEKTC) of Georgia, North Carolina, and South Carolina is an academic and community partnership that was formed with the mission to improve access to kidney transplantation and reduce disparities among African American (AA) end stage renal disease (ESRD) patients in the Southeastern United States.

METHODS/DESIGN

We describe the community-based participatory research (CBPR) process utilized in planning the Reducing Disparities In Access to kidNey Transplantation (RaDIANT) Community Study, a trial developed by the SEKTC to reduce health disparities in access to kidney transplantation among AA ESRD patients in Georgia, the state with the lowest kidney transplant rates in the nation. The SEKTC Coalition conducted a needs assessment of the ESRD population in the Southeast and used results to develop a multicomponent, dialysis facility-randomized, quality improvement intervention to improve transplant access among dialysis facilities in GA. A total of 134 dialysis facilities are randomized to receive either: (1) standard of care or "usual" transplant education, or (2) the multicomponent intervention consisting of transplant education and engagement activities targeting dialysis facility leadership, staff, and patients within dialysis facilities. The primary outcome is change in facility-level referral for kidney transplantation from baseline to 12 months; the secondary outcome is reduction in racial disparity in transplant referral.

DISCUSSION

The RaDIANT Community Study aims to improve equity in access to kidney transplantation for ESRD patients in the Southeast.

TRIAL REGISTRATION

Clinicaltrials.gov number NCT02092727.

Race/ethnicity, age, and risk of hospital admission and length of stay during the first year of maintenance hemodialysis

BACKGROUND AND OBJECTIVES

Although patients undergoing maintenance hemodialysis have exceptionally high hospitalization rates, the risk factors for hospitalizations are unclear. This study sought to examine hospitalization rates among hemodialysis patients in the United States according to both race/ethnicity and age.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

US Renal Data System data on 563,281 patients beginning maintenance hemodialysis between 1995 and 2009 were analyzed. Rates of hospital admission and number of hospital days for all-cause and cause-specific hospitalizations during the first year of dialysis were compared among blacks, whites, and Hispanics in the entire cohort and subgroups stratified by age.

RESULTS

After multiple adjustments, compared with whites, Hispanics overall had lower rates of both all-cause hospital days (adjusted rate ratio [aRR], 0.91; 95% confidence interval [95% CI], 0.90 to 0.93; P<0.001) and hospital admissions (aRR, 0.89; 95% CI, 0.88 to 0.90; P<0.001), whereas blacks had a lower rate of all-cause admissions (aRR, 0.95; 95% CI, 0.94 to 0.96; P<0.001). The racial/ethnic differences, however, varied by age. Hispanics exhibited the lowest rates of hospital days and admissions for all age groups≤70 years, but those >80 years had higher rates than their white counterparts. The adjusted black-to-white rate ratios exhibited a U-shaped pattern with age, with higher rates for blacks in the younger and older age groups. Hospitalization rates for dialysis-related infections were markedly higher in blacks and Hispanics than whites, which were consistent in all age groups for blacks (aRRs for hospital days ranged from 1.09 to 1.36) and all ages>60 years for Hispanics (aRRs ranged from 1.20 to 1.38).

CONCLUSIONS

There are significant racial/ethnic differences in hospitalization rates within first year of dialysis, which are not consistent across the age groups and also differ by causes of hospitalization. Overall, blacks and Hispanics had lower rates of all-cause hospital admissions than whites. However, younger and older blacks and older Hispanics were at greatest risk.

Impact of age, race and ethnicity on dialysis patient survival and kidney transplantation disparities

BACKGROUND

Prior studies show that African-American and Hispanic dialysis patients have lower mortality risk than whites. Recent age-stratified analyses suggest this survival advantage may be limited to younger age groups, but did not concurrently compare Hispanic, African-American, and white patients, nor account for differences in nutritional and inflammatory status as potential confounders. Minorities experience inequities in kidney transplantation access, but it is unknown whether these racial/ethnic disparities differ across age groups.

METHODS

The associations between race/ethnicity with all-cause mortality and kidney transplantation were separately examined among 130,909 adult dialysis patients from a large national dialysis organization (entry period 2001-2006, follow-up through 2009) within 7 age categories using Cox proportional hazard models adjusted for case-mix and malnutrition and inflammatory surrogates.

RESULTS

African-Americans had similar mortality versus whites in younger age groups (18-40 years), but decreased mortality in older age groups (>40 years). In contrast, Hispanics had lower mortality versus whites across all ages. In sensitivity analyses using competing risk regression to account for differential kidney transplantation rates across racial/ethnic groups, the African-American survival advantage was limited to >60-years age categories. African-Americans and Hispanics were less likely to undergo kidney transplantation from all donor types versus whites across all ages, and these disparities were even more pronounced for living donor kidney transplantation (LDKT).

CONCLUSIONS

Hispanic dialysis patients have greater survival versus whites across all ages; in African-Americans, this survival advantage is limited to patients >40 years of age. Minorities are less likely to undergo kidney transplantation, particularly LDKT, across all ages.

Increased risk of death in African American patients with end-stage renal disease secondary to lupus

Background

Systemic lupus erythematosus (SLE) is a devastating systemic disease that can lead to end-stage renal disease (ESRD). Our goal was to assess the relative mortality risk associated with race in pediatric and adult populations with ESRD secondary to SLE maintained on hemodialysis (HD).

Methods

We identified an inception cohort of patients who were started on HD in January 1990 from data collected by the United States Renal Data System (USRDS). Kaplan–Meier survival analyses were performed in these patients using the time at risk from 1 January 1990 through 31 December 2010, the last date of the USRDS data collection period in this dataset. Cox proportional hazard models were used to assess mortality, adjusted for age at dialysis initiation. Subjects were censored at transplantation or end of follow-up.

Results

There were 1580 patients with ESRD secondary to SLE, 252 pediatric patients (62% African American) and 1328 adults (56% African American). African American pediatric patients with ESRD secondary to SLE had a 2-fold increased risk of death compared with African American children with other causes of ESRD [hazard ratio (HR): 2.1, 95% confidence interval (CI): 1.4–2.9, P < 0.01]. Increased risk of death was also seen in African American adults with ESRD secondary to SLE compared with both Caucasians with ESRD secondary to SLE (HR: 2.3, 95% CI: 1.2–4.2, P < 0.01) and African American adults with ESRD secondary to other diseases (HR: 1.2, 95% CI: 1.1–1.4, P < 0.01).

Conclusion

Our study suggests that there is a significant increased risk for mortality in African American children and adults with ESRD secondary to SLE. This suggests that African Americans with ESRD secondary to SLE need aggressive monitoring.

Racial differences in survival among hemodialysis patients after coronary artery bypass grafting

The aim of this study was to examine racial differences in long-term survival among hemodialysis patients after coronary artery bypass grafting (CABG). To our knowledge this has not been previously addressed in the literature. Black and white hemodialysis patients undergoing first-time, isolated CABG procedures between 1992 and 2011 were compared. Survival probabilities were computed using the Kaplan-Meier product-limit method and stratified by race. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model. A total of 207 (2%) patients were on hemodialysis at the time of CABG. White (n = 80) hemodialysis patients had significantly decreased 5-year survival compared with black (n = 127) patients (adjusted HR = 1.9, 95% CI = 1.2-2.8). Our finding provides useful outcome information for surgeons, primary care providers, and their patients.

The relationship of age, race, and ethnicity with survival in dialysis patients

BACKGROUND AND OBJECTIVES

Reports on the racial and ethnic differences in dialysis patient survival rates have been inconsistent. The literature suggests that these survival differences may be modified by age as well as categorizing white race as inclusive of Hispanic ethnicity. The goal of this study was to better understand these associations by examining survival among US dialysis patients by age, ethnicity, and race.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Between 1995 and 2009, 1,282,201 incident dialysis patients ages 18 years or older were identified in the United States Renal Data System. Dialysis survival was compared among non-Hispanic blacks, non-Hispanic whites, and Hispanics overall and stratified by seven age groups.

RESULTS

The median duration of follow-up was 22.3 months. Compared with non-Hispanic whites, a lower mortality risk was seen in Hispanics in all age groups. Consequently, when Hispanic patients were excluded from the white race, the mortality rates in white race all increased. Using non-Hispanic whites as the reference, a significantly lower mortality risk for non-Hispanic blacks was consistently observed in all age groups above 30 years (unadjusted hazard ratios ranged from 0.70 to 0.87; all P<0.001). In the 18- to 30-years age group, there remained an increased mortality risk in blacks versus non-Hispanic whites after adjustment for case mix (adjusted hazard ratio=1.19, 95% confidence interval=1.13-1.25).

CONCLUSIONS

The mortality risk was lowest in Hispanics, intermediate in non-Hispanic blacks, and highest in non-Hispanic whites. This pattern generally holds in all age groups except for the 18- to 30-years group, where the adjusted mortality rate for non-Hispanic blacks exceeds the adjusted mortality rate of non-Hispanic whites.

Trends in relative mortality between Hispanic and non-Hispanic whites initiating dialysis: a retrospective study of the US Renal Data System

BACKGROUND

Hispanic patients undergoing long-term dialysis experience better survival compared with non-Hispanic whites. It is unknown whether this association differs by age, has changed over time, or is due to differential access to kidney transplantation.

STUDY DESIGN

National retrospective cohort study.

SETTING & PARTICIPANTS

Using the US Renal Data System, we identified 615,618 white patients 18 years or older who initiated dialysis therapy between January 1, 1995, and December 31, 2007.

PREDICTORS

Hispanic ethnicity (vs non-Hispanic whites), year of end-stage renal disease incidence, age (as potential effect modifier).

OUTCOMES

All-cause and cause-specific mortality.

RESULTS

We found that Hispanics initiating dialysis therapy experienced lower mortality, but age modified this association (P < 0.001). Compared with non-Hispanic whites, mortality in Hispanics was 33% lower at ages 18-39 years (adjusted cause-specific HR [HRcs], 0.67; 95% CI, 0.64-0.71) and 40-59 years (HRcs, 0.67; 95% CI, 0.66-0.68), 19% lower at ages 60-79 years (HRcs, 0.81; 95% CI, 0.80-0.82), and 6% lower at 80 years or older (HRcs, 0.94; 95% CI, 0.91-0.97). Accounting for the differential rates of kidney transplantation, the associations were attenuated markedly in the younger age strata; the survival benefit for Hispanics was reduced from 33% to 10% at ages 18-39 years (adjusted subdistribution-specific HR [HRsd], 0.90; 95% CI, 0.85-0.94) and from 33% to 19% among those aged 40-59 years (HRsd, 0.81; 95% CI, 0.80-0.83).

LIMITATIONS

Inability to analyze Hispanic subgroups that may experience heterogeneous mortality outcomes.

CONCLUSIONS

Overall, Hispanics experienced lower mortality, but differential access to kidney transplantation was responsible for much of the apparent survival benefit noted in younger Hispanics.

Association of ethnicity and survival in peritoneal dialysis: a cohort study of incident patients in Brazil

BACKGROUND

There are no available epidemiologic studies about the impact of ethnicity on outcomes of patients treated with peritoneal dialysis (PD) in South America. This study aims to assess the effect of ethnicity on the mortality of incident PD patients in Brazil.

STUDY DESIGN

Prospective observational cohort study of incident patients treated with PD.

SETTINGS & PARTICIPANTS

Patients 18 years or older who started PD therapy between December 2004 and October 2007 in 114 Brazilian dialysis centers.

PREDICTORS

Self-reported ethnicity defined by the Brazilian Institute of Geography and Statistics as black and brown versus white patients and baseline demographic, socioeconomic, clinical, and laboratory data were collected at baseline.

OUTCOME

Mortality, using cumulative mortality curves in which kidney transplantation and transfer to hemodialysis therapy were treated as competing end points. Multivariate Cox proportional hazards analysis was used to adjust for gradually more potential explanatory variables, censored for kidney transplantation and transfer to hemodialysis therapy. Analyses were performed for all patients, as well as stratified for elderly (aged ≥65 years) and nonelderly patients.

RESULTS

1,370 patients were white, 516 were brown, and 273 were black. The competing-risk model showed higher mortality in white patients compared with black and brown patients. With white patients as the reference, Cox proportional hazards analysis showed a crude HR for mortality of 0.77 (95% CI, 0.56-1.05) for black and 0.74 (95% CI, 0.59-0.94) for brown patients. After adjusting for potential explanatory factors, HRs were 0.67 (95% CI, 0.48-0.95) and 0.77 (95% CI, 0.43-1.01), respectively. The same results were observed in elderly and nonelderly patients.

LIMITATIONS

Ethnicity was self-determined and some misclassification might have occurred.

CONCLUSIONS

Black and brown Brazilian incident PD patients have a lower mortality risk compared with white patients.

Geographic variation in black-white differences in end-of-life care for patients with ESRD

BACKGROUND AND OBJECTIVES

Patterns of end-of-life care among patients with ESRD differ by race. Whether the magnitude of racial differences in end-of-life care varies across regions is not known.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This observational cohort study used data from the US Renal Data System and regional health care spending patterns from the Dartmouth Atlas of Healthcare. The cohort included 101,331 black and white patients 18 years and older who initiated chronic dialysis or received a kidney transplant between June 1, 2005, and September 31, 2008, and died before October 1, 2009. Black-white differences in the odds of in-hospital death, dialysis discontinuation, and hospice referral by quintile of end-of-life expenditure index (EOL-EI) were examined.

RESULTS

In adjusted analyses, the odds ratios for dialysis discontinuation for black versus white patients ranged from 0.47 (95% confidence interval=0.43 to 0.51) in the highest quintile of EOL-EI to 0.63 (95% confidence interval=0.54 to 0.74) in the lowest quintile (P for interaction<0.001). Hospice referral ranged from 0.55 (95% confidence interval=0.50 to 0.60) in the highest quintile of EOL-EI to 0.82 (95% confidence interval=0.69 to 0.96) in the lowest quintile (P for interaction<0.001). The association of race with in-hospital death also differed in magnitude across quintiles of EOL-EI, ranging from 1.21 (95% confidence interval=1.08 to 1.35) in the highest quintile of EOL-EI to 1.47 (95% confidence interval=1.27 to 1.71) in the second quintile (P for interaction<0.001).

CONCLUSIONS

There are pronounced black-white differences in patterns of hospice referral and dialysis discontinuation among patients with ESRD that vary substantially across regions of the United States.