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

Sociodemographic Disparities in Adults with Kidney Failure: A Meta-Analysis

This meta-analysis aims to assess current evidence regarding sociodemographic disparities among adults with kidney failure. Medline, Scopus, Web of Science, CENTRAL, and Google Scholar were systematically searched from inception to 20 February 2022. Overall, 165 cohort studies were included. Compared to White patients, dialysis survival was significantly better among Black (hazard ratio-HR: 0.68; 95% CI: 0.61-0.75), Asian (HR: 0.67; 95% CI: 0.61-0.72) and Hispanic patients (HR: 0.80; 95% CI: 0.73-0.88). Black individuals were associated with lower rates of successful arteriovenous fistula use, peritoneal dialysis and kidney transplantation, as well as with worse graft survival. Overall survival was significantly better in females after kidney transplantation compared to males (HR: 0.87; 95% CI: 0.84-0.90). Female sex was linked to higher rates of central venous catheter use and a lower probability of kidney transplantation. Indices of low SES were associated with higher mortality risk (HR: 1.22, 95% CI: 1.14-1.31), reduced rates of dialysis with an arteriovenous fistula, peritoneal dialysis and kidney transplantation, as well as higher graft failure risk. In conclusion, Black, Asian and Hispanic patients present better survival in dialysis, while Black, female and socially deprived patients demonstrate lower rates of successful arteriovenous fistula use and limited access to kidney transplantation. PROSPERO registration: CRD42022300839.

Differences in Outcomes by Place of Origin among Hispanic Patients with Kidney Failure

SIGNIFICANCE STATEMENT

Hispanic patients are known to have a higher risk of kidney failure and lower rates of home dialysis use and kidney transplantation than non-Hispanic White patients. However, it is unknown whether these outcomes differ within the Hispanic community, which is heterogeneous in its members' places of origins. Using United States Renal Data System data, the authors found similar adjusted rates of home dialysis use for patients originating from places outside the United States and US-born Hispanic patients, whereas the adjusted risk of mortality and likelihood of transplantation differed depending on place (country or territory) of origin. Understanding the heterogeneity in kidney disease outcomes and treatment within the Hispanic community is crucial in designing interventions and implementation strategies to ensure that Hispanic individuals with kidney failure have equitable access to care.

BACKGROUND

Compared with non-Hispanic White groups, Hispanic individuals have a higher risk of kidney failure yet lower rates of living donor transplantation and home dialysis. However, how home dialysis, mortality, and transplantation vary within the Hispanic community depending on patients' place of origin is unclear.

METHODS

We identified adult Hispanic patients from the United States Renal Data System who initiated dialysis in 2009-2017. Primary exposure was country or territory of origin (the United States, Mexico, US-Puerto Rico, and other countries). We used logistic regression to estimate differences in odds of initiating home dialysis and competing risk models to estimate subdistribution hazard ratios (SHR) of mortality and kidney transplantation.

RESULTS

Of 137,039 patients, 44.4% were US-born, 30.9% were from Mexico, 12.9% were from US-Puerto Rico, and 11.8% were from other countries. Home dialysis rates were higher among US-born patients, but not significantly different after adjusting for demographic, medical, socioeconomic, and facility-level factors. Adjusted mortality risk was higher for individuals from US-Puerto Rico (SHR, 1.04; 95% confidence interval [CI], 1.01 to 1.08) and lower for Mexico (SHR, 0.80; 95% CI, 0.78 to 0.81) and other countries (SHR, 0.83; 95% CI, 0.81 to 0.86) compared with US-born patients. The adjusted rate of transplantation for Mexican or US-Puerto Rican patients was similar to that of US-born patients but higher for those from other countries (SHR, 1.22; 95% CI, 1.15 to 1.30).

CONCLUSIONS

Hispanic people from different places of origin have similar adjusted rates of home dialysis but different adjusted rates of mortality and kidney transplantation. Further research is needed to understand the mechanisms underlying these observed differences in outcomes.

The Complex Patchwork of Transportation for In-Center Hemodialysis

Reliable transportation is an important determinant of access to health care and health outcomes that carries particular significance for people with ESKD. In the United States, there are almost half a million patients receiving treatment with in-center dialysis, translating into more than 70 million roundtrips to dialysis centers annually. Difficulty with transportation can interfere with patients' quality of life and contribute to missed or shortened dialysis treatments, increasing their risk for hospitalization. Medicare, the principal payer for dialysis in this country, has not traditionally provided coverage for nonemergency medical transportation, placing the burden of traveling to and from the dialysis center on patients and families and a range of other private and public entities that were not designed and are poorly equipped for this purpose. Here, we review the relationship between access to reliable transportation and health outcomes such as missed and shortened dialysis treatments, hospitalizations, and quality of life. We also describe current approaches to the delivery of transportation for patients receiving in-center hemodialysis, highlighting potential opportunities for improvement.

Association of Hyperkalemia and Hypokalemia with Patient Characteristics and Clinical Outcomes in Japanese Hemodialysis (HD) Patients

This study aimed to examine the characteristics and clinical outcomes of Japanese hemodialysis patients with dyskalemia. A retrospective study was conducted using a large Japanese hospital group database. Outpatients undergoing thrice-a-week maintenance hemodialysis were stratified into hyperkalemia, hypokalemia, and normokalemia groups based on their pre-dialysis serum potassium (sK) levels during the three-month baseline period. Baseline characteristics of the three groups were described and compared for the following outcomes during follow-up: all-cause mortality, all-cause hospitalization, major adverse cardiovascular events (MACE), cardiac arrest, fatal arrythmia, and death related to arrhythmia. The study included 2846 eligible patients, of which 67% were men with a mean age of 65.65 (SD: 12.63) years. When compared with the normokalemia group (n = 1624, 57.06%), patients in the hypokalemia group (n = 313, 11.00%) were older and suffered from malnutrition, whereas patients in the hyperkalemia group (n = 909, 31.94%) had longer dialysis vintage. The hazard ratios for all-cause mortality and MACE in the hypokalemia group were 1.47 (95% confidence interval [CI], 1.13–1.92) and 1.48 (95% CI, 1.17–1.86), respectively, whereas that of death related to arrhythmia in the hyperkalemia group was 3.11 (95% CI, 1.03–9.33). Thus, dyskalemia in maintenance hemodialysis patients was associated with adverse outcomes, suggesting the importance of optimized sK levels.

Cutaneous squamous cell carcinoma and mortality in end-stage renal disease

BACKGROUND

In the general population, cutaneous squamous cell carcinoma (cSCC) is associated with increased all-cause mortality. Transplant patients have been shown to have an increased risk of developing cSCC, and their cSCC is associated with an increased risk for mortality. In end-stage renal disease (ESRD) patients, there is extensive mortality and immune dysfunction. Because of this immune system dysfunction, we examined whether cSCC is associated with increased risk of all-cause mortality among ESRD patients, as well as the risk factors for cSCC.

METHODS

We analyzed ESRD patients in the United States Renal Data System from 2004-2014, excluding organ transplant recipients. We assessed mortality using a Cox Proportional Hazards (CPH) model to control for various demographic and clinical parameters, identified using international classification of diseases (ICD)-9 codes.

RESULTS

Of the 1,035,193 patients included, 624 (0.1%) were diagnosed with cSCC. The median survival time for those with cSCC was 3.91 years [95% confidence interval (CI) = 3.67-4.15], versus 2.92 years [95%CI = 2.92-2.93] for patients without cSCC. ESRD patients with cSCC were at lower risk of death [adjusted hazard ratio = 0.75; 95%CI = 0.69-0.82] compared to those without. Decreased risk of death was also associated with parameters such as black race, Hispanic ethnicity, tobacco dependence and actinic keratosis. Increased mortality risk was associated with increasing age, male sex, hemodialysis (versus peritoneal dialysis) and alcohol dependence.

CONCLUSIONS

Contrary to expectations, ESRD patients with a cSCC diagnosis showed reduced all-cause mortality risk relative to those without. The reason for this discrepancy remains unclear, suggesting the need for further study.

Patients with end-stage renal disease and diabetes had similar survival rates whether they received hemodialysis or peritoneal dialysis

BACKGROUND

The survival rate of patients with diabetes mellitus (DM) and end-stage renal disease (ESRD) undergoing maintenance dialysis, including hemodialysis (HD) and peritoneal dialysis (PD), is markedly lower than that observed in patients with ESRD without DM.

METHODS

We used propensity score matching to balance the clinical characteristics of patients from the HD and PD groups. We compared the survival rate between HD or PD, followed by Cox regression analyses accounting for age, Charlson comorbidity index (CCI), body mass index (BMI), and serum albumin levels to examine the outcome influence of dialysis modalities.

RESULTS

During follow-up, there were 19 (18.1%) and 18 (17.1%) deaths among patients who underwent HD and PD, respectively (P = 0.856). Kaplan-Meier survival analyses showed no significant difference in overall survival between patients in the HD and PD groups. Cox regression analyses stratified based on age, CCI, BMI, and serum albumin demonstrated that the choice of HD over PD did not influence survival.

CONCLUSIONS

Regardless of age, CCI, BMI, and albumin level, patients with DM and ESRD had similar survival rates whether they received HD or PD in China. The choice of dialysis modality should be individualized according to patients' physical status and local practices for patients with DM and ESRD.

Waiting-List and early posttransplant prognosis among ethnoracial groups: Data from the organ procurement and transplantation network

Background

Racial/ethnic disparity in waiting-list mortality among candidates listed for kidney transplantation (KT) in the United States remains unclear. We aimed to assess racial/ethnic disparity in waiting-list prognosis among patients listed for KT in the United States in the current era.

Methods

We compared waiting-list and early posttransplant in-hospital mortality or primary nonfunction (PNF) among adult (age ≥18 years) white, black, Hispanic, and Asian patients listed for only KT in the United States between July 1, 2004 and March 31, 2020.

Results

Of the 516,451 participants, 45.6%, 29.8%, 17.5%, and 7.1% were white, black, Hispanic, and Asian, respectively. Mortality on the 3-year waiting list (including patients who were removed for deterioration) was 23.2%, 16.6%, 16.2%, and 13.8% in white, black, Hispanic, and Asian patients, respectively. The cumulative incidence of posttransplant in-hospital death or PNF after KT was 3.3%, 2.5%, 2.4%, and 2.2% in black, white, Hispanic, and Asian patients,respectively. White candidates had the highest mortality risk on the waiting list or of becoming too sick for a transplant, while black (adjusted hazard ratio, [95% confidence interval, CI], 0.67 [0.66-0.68]), Hispanic (0.59 [0.58-0.60]), and Asian (0.54 [0.52-0.55]) candidates had a lower risk. Black KT recipients (odds ratio, [95% CI] 1.29 [1.21-1.38]) had a higher risk of PNF or death before discharge than white patients. After controlling confounders, black recipients (0.99 [0.92-1.07]) had a similar higher risk of posttransplant in-hospital mortality or PNF as white patients than Hispanic and Asian counterparts.

Conclusions

Despite having a better socioeconomic status and being allocated better kidneys, white patients had the worst prognosis during the waiting periods. Black recipients and white recipients have higher posttransplant in-hospital mortality or PNF.

Association Between Long-term Ambient PM2.5 Exposure and Cardiovascular Outcomes Among US Hemodialysis Patients

RATIONALE & OBJECTIVE

Ambient PM_2.5 (particulate matter with a diameter of 2.5 microns) is a ubiquitous air pollutant with established adverse cardiovascular (CV) effects. However, quantitative estimates of the association between PM_2.5 exposure and CV outcomes in the setting of kidney disease are limited. This study assessed the association of long-term PM_2.5 exposure with CV events and cardiovascular disease (CVD)-specific mortality among patients receiving maintenance in-center hemodialysis (HD).

STUDY DESIGN

Retrospective cohort study.

SETTINGS & PARTICIPANTS

314,079 adult kidney failure patients initiating HD between 2011 and 2016 identified from the US Renal Data System.

EXPOSURE

Estimated daily ZIP code-level PM_2.5 concentrations were used to calculate each participant's annual average PM_2.5 exposure based on the dialysis clinics visited during the 365 days before the outcome.

OUTCOME

CV event and CVD-specific mortality were ascertained based on ICD-9/ICD-10 diagnostic codes and recorded cause of death from Centers for Medicare & Medicaid Services form 2746.

ANALYTICAL APPROACH

Discrete time hazards models were used to estimate hazards ratios per 1 μg/m³ greater annual average PM_2.5, adjusting for temperature, humidity, day of the week, season, age at baseline, race, employment status, and geographic region. Effect measure modification was assessed for age, sex, race, and baseline comorbidities.

RESULTS

Each 1 μg/m³ greater annual average PM_2.5 was associated with a greater rate of CV events (HR, 1.02 [95% CI, 1.01-1.02]) and CVD-specific mortality (HR, 1.02 [95% CI, 1.02-1.03]). The association was more pronounced for people who initiated dialysis at an older age, had chronic obstructive pulmonary disease (COPD) at baseline, or were Asian. Evidence of effect modification was also observed across strata of race, and other baseline comorbidities.

LIMITATIONS

Potential exposure misclassification and unmeasured confounding.

CONCLUSIONS

Long-term ambient PM_2.5 exposure was associated with CVD outcomes among patients receiving maintenance in-center HD. Stronger associations between long-term PM_2.5 exposure and adverse effects were observed among patients who were of advanced age, had COPD, or were Asian.

PLAIN-LANGUAGE SUMMARY

Long-term exposure to air pollution, also called PM_2.5, has been linked to adverse cardiovascular outcomes. However, little is known about the association of PM_2.5 and outcomes among patients receiving dialysis, who are individuals with high cardiovascular disease burdens. We conducted an epidemiological study to assess the association between the annual PM_2.5 exposure and cardiovascular events and death among patients receiving regular outpatient hemodialysis in the United States between 2011 and 2016. We found a higher risk of heart attacks, strokes, and related events in patients exposed to higher levels of air pollution. Stronger associations between air pollution and adverse health events were observed among patients who were older at the start of dialysis, had chronic obstructive pulmonary disease, or were Asian. These findings bolster the evidence base linking air pollution and adverse health outcomes and may inform policy makers and clinicians.

Transplantation Mediates Much of the Racial Disparity in Survival from Childhood-Onset Kidney Failure

BACKGROUND

The role of kidney transplantation in differential survival in Black and White patients with childhood-onset kidney failure is unexplored.

METHODS

We analyzed 30-year cohort data of children beginning RRT before 18 years of age between January 1980 and December 2017 (n=28,337) in the US Renal Data System. Cox regression identified transplant factors associated with survival by race. The survival mediational g-formula estimated the excess mortality among Black patients that could be eliminated if an intervention equalized their time with a transplant to that of White patients.

RESULTS

Black children comprised 24% of the cohort and their crude 30-year survival was 39% compared with 57% for White children (log rank P<0.001). Black children had 45% higher risk of death (adjusted hazard ratio [aHR], 1.45; 95% confidence interval [95% CI], 1.36 to 1.54), 31% lower incidence of first transplant (aHR, 0.69; 95% CI, 0.67 to 0.72), and 39% lower incidence of second transplant (aHR, 0.61; 95% CI, 0.57 to 0.65). Children and young adults are likely to require multiple transplants, yet even after their first transplant, Black patients had 11% fewer total transplants (adjusted incidence rate ratio [aIRR], 0.89; 95% CI, 0.86 to 0.92). In Black patients, grafts failed earlier after first and second transplants. Overall, Black patients spent 24% less of their RRT time with a transplant than did White patients (aIRR, 0.76; 95% CI, 0.74 to 0.78). Transplantation compared with dialysis strongly protected against death (aHR, 0.28; 95% CI, 0.16 to 0.48) by time-varying analysis. Mediation analyses estimated that equalizing transplant duration could prevent 35% (P<0.001) of excess deaths in Black patients.

CONCLUSIONS

Equalizing time with a functioning transplant for Black patients may equalize survival of childhood-onset ESKD with White patients.

Effects of short-term ambient PM2.5 exposure on cardiovascular disease incidence and mortality among U.S. hemodialysis patients: a retrospective cohort study

BACKGROUND

Ambient PM_2.5 is a ubiquitous air pollutant with demonstrated adverse health impacts in population. Hemodialysis patients are a highly vulnerable population and may be particularly susceptible to the effects of PM_2.5 exposure. This study examines associations between short-term PM_2.5 exposure and cardiovascular disease (CVD) and mortality among patients receiving maintenance in-center hemodialysis.

METHODS

Using the United State Renal Data System (USRDS) registry, we enumerated a cohort of all US adult kidney failure patients who initiated in-center hemodialysis between 1/1/2011 and 12/31/2016. Daily ambient PM_2.5 exposure estimates were assigned to cohort members based on the ZIP code of the dialysis clinic. CVD incidence and mortality were ascertained through 2016 based on USRDS records. Discrete time hazards regression was used to estimate the association between lagged PM_2.5 exposure and CVD incidence, CVD-specific mortality, and all-cause mortality 1 t adjusting for temperature, humidity, day of the week, season, age at baseline, race, employment status, and geographic region. Effect measure modification was assessed for age, sex, race, and comorbidities.

RESULTS

Among 314,079 hemodialysis patients, a 10 µg/m³ increase in the average lag 0-1 daily PM_2.5 exposure was associated with CVD incidence (HR: 1.03 (95% CI: 1.02, 1.04)), CVD mortality (1.05 (95% CI: 1.03, 1.08)), and all-cause mortality (1.04 (95% CI: 1.03, 1.06)). The association was larger for people who initiated dialysis at an older age, while minimal evidence of effect modification was observed across levels of sex, race, or baseline comorbidities.

CONCLUSIONS

Short-term ambient PM_2.5 exposure was positively associated with incident CVD events and mortality among patients receiving in-center hemodialysis. Older patients appeared to be more susceptible to PM_2.5-associated CVD events than younger hemodialysis patients.

African Americans' Hemodialysis Treatment Adherence Data Assessment and Presentation: A Precision-Based Paradigm Shift to Support Quality Improvement Activities

RATIONALE & OBJECTIVE

Thrice-weekly hemodialysis can result in adequate urea clearance; however, the morbidity and mortality rates of patients treated with maintenance dialysis remain unacceptably high, partly because of nonadherence. African Americans have a higher prevalence of kidney failure treated with dialysis, greater dialysis nonadherence, and higher odds of hospitalization. We hypothesized that more precise ways of assessing dialysis treatment adherence will reflect the severity of nonadherence, distinguish patterns of nonadherence, and inform the design of personalized behavioral interventions.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

African American patients receiving hemodialysis for >90 days.

EXPOSURE

Hemodialysis.

OUTCOME

Dialysis adherence.

ANALYTICAL APPROACH

Dialysis attendance data were displayed using a dot plot, categorized based on missed and shortened treatments, and examined for patterns. Descriptive characteristics were reported. In an exploratory analysis, associations between dialysis treatment adherence and participant characteristics were evaluated using ordinary least squares regression. An analysis was performed using missed minutes of dialysis and current metrics for measuring dialysis treatment adherence (ie, missed and shortened treatments).

RESULTS

Among 113 African American patients treated with dialysis, 47% were men; the median age was 57 years (interquartile range, 46-70 years), and the median dialysis vintage was 54 months (interquartile range, 22-90 months). With rows ordered based on the total missed minutes of dialysis, the dot plot displayed a decreasing gradient in the severity of nonadherence, with novel dialysis treatment adherence categories termed as follows: consistent underdialysis, inconsistent dialysis, and consistent dialysis. Distinct patterns of nonadherence and heterogeneity emerged within these categories. Older age was consistently associated with better adherence, as determined by the analyses performed using the total missed minutes of dialysis as well as missed and shortened treatments.

LIMITATIONS

The study findings, although replicable and paradigm-shifting, might be limited by the short timeline, focus on adherence data specific to African American patients treated with dialysis, and restriction to dialysis units affiliated with 1 academic center.

CONCLUSIONS

This study presents more precise and novel ways of measuring and displaying dialysis treatment adherence. The findings introduce a more personalized approach for evaluating actual dialysis uptake. Identification of unique patterns of adherence behavior is important to inform the design of effective behavioral interventions and improve outcomes for vulnerable African American patients treated with dialysis.

COVID-19 Risk Factors and Mortality Outcomes Among Medicare Patients Receiving Long-term Dialysis

Importance

There is a need for studies to evaluate the risk factors for COVID-19 and mortality among the entire Medicare long-term dialysis population using Medicare claims data.

Objective

To identify risk factors associated with COVID-19 and mortality in Medicare patients undergoing long-term dialysis.

Design, Setting, and Participants

This retrospective, claims-based cohort study compared mortality trends of patients receiving long-term dialysis in 2020 with previous years (2013-2019) and fit Cox regression models to identify risk factors for contracting COVID-19 and postdiagnosis mortality. The cohort included the national population of Medicare patients receiving long-term dialysis in 2020, derived from clinical and administrative databases. COVID-19 was identified through Medicare claims sources. Data were analyzed on May 17, 2021.

Main Outcomes and Measures

The 2 main outcomes were COVID-19 and all-cause mortality. Associations of claims-based risk factors with COVID-19 and mortality were investigated prediagnosis and postdiagnosis.

Results

Among a total of 498 169 Medicare patients undergoing dialysis (median [IQR] age, 66 [56-74] years; 215 935 [43.1%] women and 283 227 [56.9%] men), 60 090 (12.1%) had COVID-19, among whom 15 612 patients (26.0%) died. COVID-19 rates were significantly higher among Black (21 787 of 165 830 patients [13.1%]) and Hispanic (13 530 of 86 871 patients [15.6%]) patients compared with non-Black patients (38 303 of 332 339 [11.5%]), as well as patients with short (ie, 1-89 days; 7738 of 55 184 patients [14.0%]) and extended (ie, ≥90 days; 10 737 of 30 196 patients [35.6%]) nursing home stays in the prior year. Adjusting for all other risk factors, residing in a nursing home 1 to 89 days in the prior year was associated with a higher hazard for COVID-19 (hazard ratio [HR] vs 0 days, 1.60; 95% CI 1.56-1.65) and for postdiagnosis mortality (HR, 1.31; 95% CI, 1.25-1.37), as was residing in a nursing home for an extended stay (COVID-19: HR, 4.48; 95% CI, 4.37-4.59; mortality: HR, 1.12; 95% CI, 1.07-1.16). Black race (HR vs non-Black: HR, 1.25; 95% CI, 1.23-1.28) and Hispanic ethnicity (HR vs non-Hispanic: HR, 1.68; 95% CI, 1.64-1.72) were associated with significantly higher hazards of COVID-19. Although home dialysis was associated with lower COVID-19 rates (HR, 0.77; 95% CI, 0.75-0.80), it was associated with higher mortality (HR, 1.18; 95% CI, 1.11-1.25).

Conclusions and Relevance

These results shed light on COVID-19 risk factors and outcomes among Medicare patients receiving long-term chronic dialysis and could inform policy decisions to mitigate the significant extra burden of COVID-19 and death in this population.

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.

Mortality of hemodialysis patients is associated with their clinical situation at the start of treatment

INTRODUCTION

Previous reports have shown very high mortality among hemodialyisis patients. Our goal was to analyze the mortality of patients in the Renal Registry of Patients who remained exclusively on hemodialysis treatment.

METHODS

The cohort of patients who started treatment in the community of Castilla-La Mancha between 2010 and 2012 and remained on hemodialysis treatment was analysed until the end of 2017. Age, sex, primary kidney disease, vascular access, hemoglobin, Charlson index and serum albumin were included.

RESULTS

Mortality rate was 63,4% after 5 years and 76% at the end of the study, with no difference between males and females, and was linked to an older age, urgent onset or in those with acute deterioration of chronic kidney disease, the use of catheters or albumin less than 3.5 g/dl.

CONCLUSIONS

Mortality in patients who remain on hemodialysis is very high and is associated with non-modifiable factors such as age but also others that we can prevent or treat such as type of vascular access or nutrition status at the beginning of treatment.

Association between ethnicity and kidney transplant waitlist outcomes beyond estimated post-transplant survival score

White kidney transplant candidates have the highest pre-transplant mortality rate compared to other ethnicities. The reason for a higher mortality rate is not well-understood. Estimated post-transplant survival (EPTS) score has been used to predict patient survival after transplant and may be associated with pre-transplant survival. First-time kidney transplant candidates listed between 2015 and 2018 were identified from the Organ Procurement Transplantation Network database. Individuals listed for multiple organs, at multiple centers, and age <18 years were excluded. We examined the impact of ethnicity on waitlist mortality and delisting. A total of 114 806 candidates were included. The study population was categorized into four groups which were 43% white, 28% Black, 19.2% Hispanic, and 9.8% "other ethnicities." At 5.2 years, the cumulative incidences of death and delist were 32%, 31%, 29%, and 26%, respectively. Compared to whites, adjusted subdistribution hazard ratio (aSHR) for death and delist among Black, Hispanics, and "other ethnicities" were 0.92 (95% CI 0.89-0.95), 0.89 (95% CI 0.85-0.91), and 0.76 (95% CI 0.72-0.80) after adjustment by EPTS along with other factors, respectively. After adjusting for EPTS score along with additional confounding factors and functional status at initial listing, white ethnicity was independently associated with an increased risk for death and delist.

Antibody Response to COVID-19 vaccination in Patients Receiving Dialysis

Background

Patients receiving dialysis may mount impaired responses to COVID19 vaccination.

Methods

We report antibody response to vaccination from 1140 patients without, and 493 patients with pre-vaccination SARS-CoV-2 RBD antibody. We used commercially available assays (Siemens) to test remainder plasma monthly in association with vaccination date and type, and assess prevalence of absent total receptor binding antibody, and absent or attenuated (index value < 10) semiquantitative receptor binding domain IgG index values. We used Poisson regression to evaluate risk factors for absent or attenuated response to vaccination.

Results

Among patients who were seronegative versus seropositive before vaccination, 62% and 56% were ≥65 years old, 20% and 24% were Hispanic, and 22% and 23% were Black. Median IgG index values rose steadily over time, and were higher among the seropositive than in the seronegative patients after completing vaccination (150 [25th, 75th percentile 23.2, 150.0] versus 41.6 [11.3, 150.0]). Among 610 patients who completed vaccination (assessed ≥14 days later, median 29 days later), the prevalence of absent total RBD response, and absent and attenuated semiquantitative IgG response was 4.4% (95% CI 3.1, 6.4%), 3.4% (2.4, 5.2%), and 14.3% (11.7, 17.3%) respectively. Risk factors for absent or attenuated response included longer vintage of end-stage kidney disease, and lower pre-vaccination serum albumin.

Conclusions

More than one in five patients receiving dialysis had evidence of an attenuated immune response to COVID19 vaccination.

Propensity score matched mortality comparisons of peritoneal and in-centre haemodialysis: systematic review and meta-analysis

Background

Accurate comparisons of haemodialysis (HD) and peritoneal dialysis (PD) survival based on observational studies are difficult due to substantial residual confounding that arises from imbalances between treatments. Propensity score matching (PSM) comparisons confer additional advantages over conventional methods of adjustment by further reducing selection bias between treatments. We conducted a systematic review of studies that compared mortality between in-centre HD with PD using a PSM-based approach.

Methods

A sensitive search strategy identified all citations in the PubMed, Cochrane and EMBASE databases from inception through November 2018. Pooled PD versus HD mortality hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through random-effects meta-analysis. A subsequent meta-regression explored factors to account for between-study variation.

Results

The systematic review yielded 214 citations with 17 cohort studies and 113 578 PSM incident dialysis patients. Cohort periods spanned the period 1993–2014. The pooled HR for PD versus HD was 1.06 (95% CI 0.99–1.14). There was considerable variation by country, however, mortality risks for PD versus HD remained virtually unchanged when stratified by geographical region with HRs of 1.04 (95% CI 0.94–1.15), 1.14 (95% CI 0.99–1.32) and 0.98 (0.87–1.10) for European, Asian and American cohorts, respectively. Subgroup meta-analyses revealed similar risks for patients with diabetes [HR 1.09 (95% CI 0.98–1.21)] and without diabetes [HR 0.99 (95% CI 0.90–1.09)]. Heterogeneity was substantial (I² = 87%) and was largely accounted for by differences in cohort period, study type and country of origin. Together these factors explained a substantial degree of between-studies variance (R² = 90.6%).

Conclusions

This meta-analysis suggests that PD and in-centre HD carry equivalent survival benefits. Reported differences in survival between treatments largely reflect a combination of factors that are unrelated to clinical efficacy.

Mortality of hemodialysis patients is associated with their clinical situation at the start of treatment

INTRODUCTION

Previous reports have shown very high mortality among hemodialyisis patients. Our goal was to analyze the mortality of patients in the Renal Registry of Patients who remained exclusively on hemodialysis treatment.

METHODS

The cohort of patients who started treatment in the community of Castilla-La Mancha between 2010 and 2012 and remained on hemodialysis treatment was analysed until the end of 2017. Age, sex, primary kidney disease, vascular access, hemoglobin, Charlson index and serum albumin were included.

RESULTS

Mortality rate was 63.4% after 5 years and 76% at the end of the study, with no difference between males and females, and was linked to an older age, urgent onset or in those with acute deterioration of chronic kidney disease, the use of catheters or albumin less than 3.5g/dl.

CONCLUSIONS

Mortality in patients who remain on hemodialysis is very high and is associated with non-modifiable factors such as age but also others that we can prevent or treat such as type of vascular access or nutrition status at the beginning of treatment.

Impact of health-related quality of life on survival after dialysis initiation: a prospective cohort study in Korea

Background

The effect of each health-related quality of life (HRQOL) component on hemodialysis prognosis has not been well studied. We aimed to investigate the clinical factors associated with HRQOL and the effect of HRQOL after dialysis initiation on long-term survival in an Asian population.

Methods

A total of 568 hemodialysis patients were included from a nationwide prospective cohort study. HRQOL was evaluated using the Kidney Disease Quality of Life (KDQOL) Short FormTM 1.3 at 3 months after dialysis initiation. The effect of each KDQOL item score on mortality was analyzed. Multivariable Cox analysis was performed after adjusting for age, sex, modified Charlson comorbidity index, and causes of primary kidney disease.

Results

Old age, diabetes mellitus, high comorbidities, and low serum albumin levels were associated with poor physical health status. Decreased urine output was associated with both poor physical and mental health status. The scores of 3 indices in the kidney disease domain (effect of kidney disease, social support, and dialysis staff encouragement) showed significant associations with mortality, as did the 3 indices (physical function, physical role limitation, and body pain) in the physical health domain. Neither the 4 indices in the mental health domain nor the mental composite score showed a significant association with mortality. However, a high physical composite score was associated with decreased overall patient mortality (P = 0.003). The effect of physical composite score on survival was prominent among young or middle-aged groups.

Conclusion

Poor physical health status 3 months after hemodialysis start correlates significantly with overall mortality.

Development and Validation of an Application for Follow-up of Patients Undergoing Dialysis: NefroPortátil

OBJECTIVES

To develop the NefroPortatil mobile application (app) and evaluate its effects on the management of patients undergoing dialysis.

METHODS

The first stage of the work was the development, installation, and establishment of the instructions to use the phone app as an instrument to aid in the control of fluid and food intake of 52 patients undergoing dialysis. In the second stage, the patients were monitored for 3 months and evaluated using questionnaires to measure the improvement in quality of life (Kidney Disease Quality of Life Instrument) and self-management of disease (Perceived Medical Condition Self-Management Scale) by the app. In addition, laboratory tests were performed before app use and in the first, second, and third months of its use (January to April 2018). Analysis of variance was used to analyze the laboratory data, and a paired Student's t test was used to analyze the responses to the questionnaires and as a posttest (P < .05).

RESULTS

Among the laboratory test results, serum phosphorus levels showed a significant difference (P < .04) after the app was used. A significant improvement was observed in self-management of the disease according to the Perceived Medical Condition Self-Management Scale questionnaire (P < .03). The usability of the app reached a median score of 9.65 from a total score of 10.

CONCLUSION

The NefroPortatil app improved the degree of perception of self-care of patients undergoing dialysis with chronic kidney failure, in addition to favoring nutritional control.

Racial and Ethnic Variations in Mortality Rates for Patients Undergoing Maintenance Dialysis Treated in US Territories Compared with the US 50 States

BACKGROUND AND OBJECTIVES

In the United States mortality rates for patients treated with dialysis differ by racial and/or ethnic (racial/ethnic) group. Mortality outcomes for patients undergoing maintenance dialysis in the United States territories may differ from patients in the United States 50 states.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study of using US Renal Data System data included 1,547,438 adults with no prior transplantation and first dialysis treatment between April 1, 1995 and September 28, 2012. Cox proportional hazards regression was used to calculate hazard ratios (HRs) of death for the territories versus 50 states for each racial/ethnic group using the whole cohort and covariate-matched samples. Covariates included demographics, year of dialysis initiation, cause of kidney failure, comorbid conditions, dialysis modality, and many others.

RESULTS

Of 22,828 patients treated in the territories (American Samoa, Guam, Puerto Rico, Virgin Islands), 321 were white, 666 were black, 20,299 were Hispanic, and 1542 were Asian. Of 1,524,610 patients in the 50 states, 838,736 were white, 444,066 were black, 182,994 were Hispanic, and 58,814 were Asian. The crude mortality rate (deaths per 100 patient-years) was lower for whites in the territories than the 50 states (14 and 29, respectively), similar for blacks (18 and 17, respectively), higher for Hispanics (27 and 16, respectively), and higher for Asians (22 and 15). In matched analyses, greater risks of death remained for Hispanics (HR, 1.65; 95% confidence interval, 1.60 to 1.70; P<0.001) and Asians (HR, 2.01; 95% confidence interval, 1.78 to 2.27; P<0.001) living in the territories versus their matched 50 states counterparts. There were no significant differences in mortality among white or black patients in the territories versus the 50 states.

CONCLUSIONS

Mortality rates for patients undergoing dialysis in the United States territories differ substantially by race/ethnicity compared with the 50 states. After matched analyses for comparable age and risk factors, mortality risk no longer differed for whites or blacks, but remained much greater for territory-dwelling Hispanics and Asians.

Race and Mortality in CKD and Dialysis: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

RATIONALE & OBJECTIVES

Few studies have investigated racial disparities in survival among dialysis patients in a manner that considers risk factors and mortality during the phase of kidney disease before maintenance dialysis. Our objective was to explore racial variations in survival among dialysis patients and relate them to racial differences in comorbid conditions and rates of death in the setting of kidney disease not yet requiring dialysis therapy.

STUDY DESIGN

Retrospective cohort study.

SETTINGS & PARTICIPANTS

3,288 black and white participants in the Chronic Renal Insufficiency Cohort (CRIC), none of whom were receiving dialysis at enrollment.

EXPOSURE

Race.

OUTCOME

Mortality.

ANALYTIC APPROACH

Cox proportional hazards regression was used to examine the association between race and mortality starting at: (1) time of dialysis initiation and (2) entry into the CRIC.

RESULTS

During 7.1 years of median follow-up, 678 CRIC participants started dialysis. Starting from the time of dialysis initiation, blacks had lower risk for death (unadjusted HR, 0.67; 95% CI, 0.51-0.87) compared with whites. Starting from baseline CRIC enrollment, the strength of the association between some risk factors and dialysis was notably stronger for whites than blacks. For example, the HR for dialysis onset in the presence (vs absence) of heart failure at CRIC enrollment was 1.30 (95% CI, 1.01-1.68) for blacks versus 2.78 (95% CI, 1.90-4.50) for whites, suggesting differential severity of these risk factors by race. When we included deaths occurring both before and after dialysis, risk for death was higher among blacks (vs whites) starting from CRIC enrollment (HR, 1.41; 95% CI, 1.22-1.64), but this finding was attenuated in adjusted models (HR, 1.08; 95% CI, 0.91-1.28).

LIMITATIONS

Residual confounding.

CONCLUSIONS

The apparent survival advantage among blacks over whites treated with dialysis may be attributed to selected transition of a subset of whites with more severe comorbid conditions onto dialysis.

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.

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.

Ethnic Differences in the Association of Depressive Symptoms with Clinical Outcome in Dialysis Patients

BACKGROUND

Studies show mixed results on the association between depressive symptoms and adverse clinical outcomes in patients on dialysis therapy. Ethnicity may play a role in these heterogeneous results. No studies have investigated the interplay between ethnicity and depressive symptoms on clinical outcome in this patient population. This study aims to examine interaction between ethnicity and depressive symptoms on hospitalization and mortality in dialysis patients.

METHODS

A multi-ethnic cohort in 10 dialysis centers included 687 dialysis patients between 2012 and 2017, with an average follow-up of 3.2 years. Depressive symptoms were measured using the Beck Depression Inventory. Interaction was assessed by investigating excess risk on an additive scale using both absolute rates and relative risks. Multivariable regression models included demographic, social, and clinical variables.

RESULTS

Adverse outcomes are more pronounced in native patients, compared to immigrant patients. The risk for mortality and hospitalization is considerably higher in native patients compared to immigrants. An excess risk on an additive scale indicates the presence of possible causal interaction.

CONCLUSIONS

Depressive symptoms are a risk factor for hospitalization and mortality, especially in native dialysis patients. Adverse clinical events associated with depressive symptoms differ among ethnic groups. This differential association could play a role in the conflicting findings in literature. Ethnicity is an important factor when investigating depressive symptoms and clinical outcome in dialysis patients. Future research should focus on the possible mechanisms and pathways involved in these differential associations.

Kidney Disease Among African Americans: A Population Perspective

End-stage kidney disease and earlier stages of chronic kidney disease (CKD) represent one of the most dramatic examples of racial/ethnic disparities in health in our nation. African Americans are 3 times more likely to require renal replacement therapy then their non-Hispanic white counterparts. This article describes CKD-related disparities linked to a variety of clinical, socioeconomic, and cultural factors, as well as to select social determinants of health that are defined by social positioning and often by race within the United States. Our advancing understanding of these issues has led to improvements in patient outcomes and is narrowing the gap in disparities across most aspects of CKD and CKD risk factors. There are also extensive data indicating similar improvements in quality measures for patients on dialysis therapy. This article also reviews the state of CKD in African Americans from a population perspective and provides recommendations for the way forward.

Diversity in Medical Device Clinical Trials: Do We Know What Works for Which Patients?

Policy Points: A 1993 law required the National Institutes of Health to include women and racial and ethnic minorities in relevant research studies. Most federal health agencies adopted the same policy, but the US Food and Drug Administration (FDA) did not. A 2012 law encouraged the FDA to ensure that new medical products be analyzed for safety and effectiveness for key demographic patient groups. Our study of high-risk medical devices reviewed by the FDA in 2014-2017 found that due to lack of patient diversity and publicly available data, clinicians and patients often cannot determine which devices are safe and effective for specific demographic groups.

CONTEXT

Demographic differences can influence the safety and effectiveness of medical devices; however, clinical trials of devices for adults have historically underrepresented women, people of color, and patients over age 65. The US Food and Drug Administration (FDA) Safety and Innovation Act became law in 2012, encouraging greater diversity and subgroup analyses. In 2013, the FDA reported that there was diversity in clinical trials considered "pivotal" for approval decisions and that subgroup analyses were conducted for most applications for the highest-risk medical devices. However, the FDA's report did not specify whether analyses included sufficient numbers to be meaningful, whether analyses were conducted for most major subgroups, or whether analyses included safety, effectiveness, or accuracy.

METHODS

We examined publicly available documents for all 22 medical devices that the FDA designated "highest risk" or "novel," were reviewed through the premarket approval pathway, and were scrutinized at FDA public meetings from 2014 to 2017. We evaluated patient demographics and subgroup analyses for all pivotal trials.

FINDINGS

Only 3 (14%) of the devices provided subgroup analyses for both effectiveness and safety or both sensitivity and selectivity for gender, race, and age. However, 55% of the devices reported both of those subgroup analyses for at least 1 of the 3 subgroups. Whether analyses were reported or not, the number of patients in most subgroups was too small to draw meaningful conclusions. Subgroup analyses were more likely to be reported to the FDA's Advisory Committees than in the FDA's public reviews or labeling.

CONCLUSIONS

Despite a law encouraging more diversity and subgroup analyses in pivotal trials used as the basis for FDA approval, the results of our study indicate relatively few subgroup analyses are publicly available for the highest-risk and novel medical devices. The lack of subgroup analyses makes it impossible to inform patients or physicians as to whether many newly approved medical devices are safe and effective for specific demographic subgroups defined by gender, race, and age.

CKD and ESRD in US Hispanics

Hispanics are the largest racial/ethnic minority group in the United States, and they experience a substantial burden of kidney disease. Although the prevalence of chronic kidney disease (CKD) is similar or slightly lower in Hispanics than non-Hispanic whites, the age- and sex-adjusted prevalence rate of end-stage renal disease is almost 50% higher in Hispanics compared with non-Hispanic whites. This has been attributed in part to faster CKD progression among Hispanics. Furthermore, Hispanic ethnicity has been associated with a greater prevalence of cardiovascular disease risk factors, including obesity and diabetes, as well as CKD-related complications. Despite their less favorable socioeconomic status, which often leads to limited access to quality health care, and their high comorbid condition burden, the risk for mortality among Hispanics appears to be lower than for non-Hispanic whites. This survival paradox has been attributed to a complex interplay between sociocultural and psychosocial factors, as well as other factors. Future research should focus on evaluating the long-term impact of these factors on patient-centered and clinical outcomes. National policies are needed to improve access to and quality of health care among Hispanics with CKD.

Race but not Hepatitis C co-infection affects survival of HIV+ individuals on dialysis in contemporary practice

Individuals with HIV infection are at elevated risk of developing end-stage renal disease. However, their outcomes after starting chronic dialysis in the contemporary era of widespread antiretroviral therapy are not well described. Using detailed data from a national dialysis provider, we determined HIV status by administrative codes and antiretroviral medication prescriptions, with hepatitis C virus (HCV) co-infection status provided by routinely measured serology. The survival on dialysis among 5348 individuals in the HIV⁺ group and 1863 HIV⁺/HCV⁺ individuals to a HIV^-/HCV^- reference cohort was compared. Race significantly modified the effect of HIV and HIV/HCV infection on mortality. In a multivariable model, HIV infection was not associated with an increased risk of death among Caucasians (hazard ratio 1.03, 95% confidence interval 0.91-1.16) but HIV/HCV co-infection (1.48, 1.18-1.87) was. In the same model for non-Caucasians, both HIV infection (1.44, 1.37-1.52) and HIV/HCV co-infection (1.71, 1.60-1.84) were significantly associated with higher mortality. A secondary analysis using propensity scores yielded similar results. Median follow-up for the reference group was 645 days (interquartile range 230-1323), 772 days (276-1623) for the HIV⁺ group and 777 days (334-1665) for the co-infected group. Thus, in the contemporary era of widespread antiretroviral use, HIV infection remains associated with a significant reduction in dialysis survival for non-Caucasians while HIV/HCV co-infection is associated with impaired survival regardless of race or ethnicity. Hence, interventions to improve the care for these vulnerable populations are needed.

Racial and Ethnic Differences in Mortality Associated with Serum Potassium in a Large Hemodialysis Cohort

BACKGROUND

Hyperkalemia is observed in chronic kidney disease patients and may be a risk factor for life-threatening arrhythmias and death. Race/ethnicity may be important modifiers of the potassium-mortality relationship in maintenance hemodialysis (MHD) patients given that potassium intake and excretion vary among minorities.

METHODS

We examined racial/ethnic differences in baseline serum potassium levels and all-cause and cardiovascular mortality using Cox proportional hazard models and restricted cubic splines in a cohort of 102,241 incident MHD patients. Serum potassium was categorized into 6 groups: ≤3.6, >3.6 to ≤4.0, >4.0 to ≤4.5 (reference), >4.5 to ≤5.0, >5.0 to ≤5.5, and >5.5 mEq/L. Models were adjusted for case-mix and malnutrition-inflammation cachexia syndrome (MICS) covariates.

RESULTS

The cohort was composed of 50% whites, 34% African-Americans, and 16% Hispanics. Hispanics tended to have the highest baseline serum potassium levels (mean ± SD: 4.58 ± 0.55 mEq/L). Patients in our cohort were followed for a median of 1.3 years (interquartile range 0.6-2.5). In our cohort, associations between higher potassium (>5.5 mEq/L) and higher mortality risk were observed in African-American and whites, but not Hispanic patients in models adjusted for case-mix and MICS covariates. While in Hispanics only, lower serum potassium (<3.6 mEq/L) levels were associated with higher mortality risk. Similar trends were observed for cardiovascular mortality.

CONCLUSIONS

Higher potassium levels were associated with higher mortality risk in white and African-American MHD patients, whereas lower potassium levels were associated with higher death risk in Hispanics. Further studies are needed to determine the underlying mechanisms for the differential association between potassium and mortality across race/ethnicity.

Hemodialysis Disparities in African Americans: The Deeply Integrated Concept of Race in the Social Fabric of Our Society

End-stage renal disease (ESRD) is one of the starkest examples of racial/ethnic disparities in health. Racial/ethnic minorities are 1.5 to nearly 4 times more likely than their non-Hispanic White counterparts to require renal replacement therapy (RRT), with African Americans suffering from the highest rates of ESRD. Despite improvements over the last 25 years, substantial racial differences are persistent in dialysis quality measures such as RRT modality options, dialysis adequacy, anemia, mineral and bone disease, vascular access, and pre-ESRD care. This report will outline the current status of racial disparities in key ESRD quality measures and explore the impact of race. While the term race represents a social construct, its association with health is more complex. Multiple individual and community level social determinants of health are defined by the social positioning of race in the U.S., while biologic differences may reflect distinct epigenetic changes and linkages to ancestral geographic origins. Together, these factors conspire to influence dialysis outcomes among African Americans with ESRD.

Racial-ethnic disparities in mortality and kidney transplant outcomes among pediatric dialysis patients

BACKGROUND

Previous studies in adult hemodialysis patients have shown that African-American and Hispanic patients have a lower risk of mortality in addition to a lower likelihood of kidney transplantation. However, studies of the association between race and outcomes in pediatric dialysis are sparse and often do not examine outcomes in Hispanic children. The objective was to determine if racial-ethnic disparities in mortality and kidney transplantation outcomes exist in pediatric dialysis patients.

METHODS

This was a retrospective cohort analysis of 2,697 pediatric dialysis patients (aged 0-20 years) from a large national dialysis organization (entry period 2001-2011) of non-Hispanic white, African-American, and Hispanic race-ethnicity. Associations between race-ethnicity with mortality and kidney transplantation outcomes were examined separately using competing risks methods. Logistic regression analyses were used to examine the association between race-ethnicity, with outcomes within 1 year of dialysis initiation.

RESULTS

Of the 2,697 pediatric patients in this cohort, 895 were African-American, 778 were Hispanic, and 1,024 were non-Hispanic white. After adjusting for baseline demographics, competing risk survival analysis revealed that compared with non-Hispanic whites, African-Americans had a 64 % higher mortality risk (hazards ratio [HR] = 1.64; 95 % CI 1.24-2.17), whereas Hispanics had a 31 % lower mortality risk (HR = 0.69; 95 % CI 0.47-1.01) that did not reach statistical significance. African-Americans also had higher odds of 1-year mortality after starting dialysis (odds ratio [OR] = 2.08; 95 % CI 0.95-4.58), whereas both African-Americans and Hispanics had a lower odds of receiving a transplant within 1 year of starting dialysis (OR = 0.28; 95 % CI 0.19-0.41 and OR = 0.43; 95 % CI 0.31-0.59 respectively).

CONCLUSION

In contrast to adults, African-American pediatric dialysis patients have worse survival than their non-Hispanic white counterparts, whereas Hispanics have a similar to lower mortality risk. Both African-American and Hispanic pediatric dialysis patients had a lower likelihood of kidney transplantation than non-Hispanic whites, similar to observations in the adult dialysis population.

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.

Strategies for enhancing research in aging health disparities by mentoring diverse investigators

Introduction

The Resource Centers for Minority Aging Research (RCMAR) program was launched in 1997. Its goal is to build infrastructure to improve the well-being of older racial/ethnic minorities by identifying mechanisms to reduce health disparities.

Methods

Its primary objectives are to mentor faculty in research addressing the health of minority elders and to enhance the diversity of the workforce that conducts elder health research by prioritizing the mentorship of underrepresented diverse scholars.

Results

Through 2015, 12 centers received RCMAR awards and provided pilot research funding and mentorship to 361 scholars, 70% of whom were from underrepresented racial/ethnic groups. A large majority (85%) of RCMAR scholars from longstanding centers continue in academic research. Another 5% address aging and other health disparities through nonacademic research and leadership roles in public health agencies.

Conclusions

Longitudinal, team-based mentoring, cross-center scholar engagement, and community involvement in scholar development are important contributors to RCMAR’s success.

High Serum Alkaline Phosphatase, Hypercalcaemia, Race, and Mortality in South African Maintenance Haemodialysis Patients

Objective. To determine the association between serum total alkaline phosphatase (TAP) and mortality in African maintenance haemodialysis patients (MHD). Patients and Methods. The study enrolled a total of 213 patients on MHD from two dialysis centers in Johannesburg between January 2009 and March 2016. Patients were categorized into a low TAP group (≤112 U/L) versus a high TAP group (>112 U/L) based on a median TAP of 112 U/L. Results. During the follow-up period of 7 years, there were 55 (25.8%) deaths. After adjusting for cofounders such as age, other markers of bone disorder, and comorbidity (diabetes mellitus), patients in the high TAP group had significantly higher risk of death compared to patients in the low TAP group (hazard ratio, 2.50; 95% CI 1.24-5.01, P = 0.01). Similarly, serum calcium >2.75 mmol/L was associated with increased risk of death compared to patients within levels of 2.10-2.37 mmol/L (HR 6.34, 95% CI 1.40-28.76; P = 0.02). The HR for death in white patients compared to black patients was 6.88; 95% CI 1.82-25.88; P = 0.004. Conclusion. High levels of serum alkaline phosphatase, hypercalcaemia, and white race are associated with increased risk of death in MHD patients.

Regional Variations in the Interpretation of the End-Stage Renal Disease Thirty-Month Coordination Period: Potential Implications for Patient Care

Chronic kidney disease is a non-communicable disease that is now well recognized as a major source of premature morbidity and mortality. In general, racial/ethnic minorities in the United States are more likely than non-minority groups to develop end-stage renal disease (ESRD), but paradoxically most have a lower mortality risk. Unlike most minorities, dialysis patients in Puerto Rico have a mortality risk nearly 50% higher than the national average. Multiple factors such as medical conditions, socioeconomic, environmental, and health system factors can influence health outcomes for patients with ESRD. We describe one potential health system factor that may contribute to this finding, a unique interpretation and implementation of the ESRD Medicare Secondary Payer provision in the Commonwealth of Puerto Rico. We conducted a search of regulatory documents and key stakeholder interviews to help envision the potential implications of these differences for dialysis facilities, health care providers, and patients with ESRD.

Racial and Ethnic Disparities in Survival of Children with ESRD

Observational studies have reported that black and Hispanic adults receiving maintenance dialysis survive longer than non-Hispanic white counterparts. Whether there are racial disparities in survival of children with ESRD is not clear. We compared mortality risk among non-Hispanic black, Hispanic, and non-Hispanic white children who started RRT between 1995 and 2011 and were followed through 2012. We examined all-cause mortality using adjusted Cox models. Of 12,123 children included for analysis, 1600 died during the median follow-up of 7.1 years. Approximately 25% of children were non-Hispanic black, and 26% of children were of Hispanic ethnicity. Non-Hispanic black children had a 36% higher risk of death (95% confidence interval [95% CI], 1.21 to 1.52) and Hispanic children had a 34% lower risk of death (95% CI, 0.57 to 0.77) than non-Hispanic white children. Adjustment for transplant as a time-dependent covariate abolished the higher risk of death in non-Hispanic black children (hazard ratio, 0.99; 95% CI, 0.88 to 1.12) but did not attenuate the finding of a lower risk of death in Hispanic children (hazard ratio, 0.59; 95% CI, 0.51 to 0.68). In conclusion, Hispanic children had lower mortality than non-Hispanic white children. Non-Hispanic black children had higher mortality than non-Hispanic white children, which was related to differences in access to transplantation by race. Parity in access to transplantation in children and improvements in strategies to prolong graft survival could substantially reduce disparities in mortality risk of non-Hispanic black children treated with RRT.

Social Determinants of Racial Disparities in CKD

Significant disparities in CKD rates and outcomes exist between black and white Americans. Health disparities are defined as health differences that adversely affect disadvantaged populations, on the basis of one or more health outcomes. CKD is the complex result of genetic and environmental factors, reflecting the balance of nature and nurture. Social determinants of health have an important role as environmental components, especially for black populations, who are disproportionately disadvantaged. Understanding the social determinants of health and appreciating the underlying differences associated with meaningful clinical outcomes may help nephrologists treat all their patients with CKD in an optimal manner. Altering the social determinants of health, although difficult, may embody important policy and research efforts, with the ultimate goal of improving outcomes for patients with kidney diseases, and minimizing the disparities between groups.

Age, Race and Cardiovascular Outcomes in African American Veterans

BACKGROUND

In the general population, compared wtih their White peers, African Americans suffer premature all-cause and cardiovascular (CV) deaths, attributed in part to reduced access to care and lower socioeconomic status. Prior reports indicated younger (aged 35 to 44 years) African Americans had a signficantly greater age-adjusted risk of death. Recent studies suggest that in a more egalitarian health care structure than typical United States (US) health care structures, African Americans may have similar or even better CV outcomes, but the impact of age is less well-known.

METHODS

We examined age stratified all-cause mortality, and incident coronary heart disease (CHD) and ischemic stroke in 3,072,966 patients (547,441 African American and 2,525,525 White) with an estimated glomerular filtration rate (eGFR)>60 mL/min/1.73m(2) receiving care from the US Veterans Health Administration. Outcomes were examined in Cox models adjusted for demographics, comorbidities, kidney function, blood pressure, socioeconomics and indicators of the quality of health care delivery.

RESULTS

African Americans had an overall 30% lower all-cause mortality (P<.001) and 29% lower incidence of CHD (P<.001) and higher incidence of ischemic stroke (aHR, 95%CI: 1.16, 1.13-1.18, P<.001). The lower rates of mortality and CHD were strongest in younger African Americans and attenuated across patients aged ≥70 years. Stroke rates did not differ by race in persons aged <70 years.

CONCLUSIONS

Among patients with normal eGFR and receiving care in the Veterans Health Administration, younger African Americans had lower all-cause mortality and incidence of CHD and similar rates of stroke, independent of demographic, comorbidity and socioeconomic differences. The lower all-cause mortality persisted but attenuated with increasing age and the lower incidence of CHD ended at aged ≥80 years. The higher incidence of ischemic stroke in African Americans was driven by increasing risk in patients aged ≥70 years suggesting that the improved cardiovascular outcomes were most dramatic for younger African Americans.

The Survival of Roma Minority Patients on Chronic Hemodialysis Therapy - A Romanian Multicenter Survey

OBJECTIVE

The Roma minority represents the largest ethnic group in Central and South-East European countries. Data regarding the mortality in Roma hemodialysis subjects are limited. We evaluated the 3 year mortality of ESRD Roma patients treated with hemodialysis (HD).

STUDY DESIGN AND SETTING

Our prospective cohort study included 600 ESRD patients on HD therapy recruited from 7 HD centers, from the main geographical regions of Romania. The median age of the patients was 56 (19) years, 332 (55.3%) being males, 51 (8.5%) having Roma ethnicity.

RESULTS

Roma ESRD patients initiate dialysis at a younger age, 47.8 years vs. 52.3 years (P = 0.017), present higher serum albumin (P = 0.013) and higher serum phosphate levels (P = 0.021). In the Roma group, the overall 3 year mortality was higher when compared to Caucasians (33.3% vs. 24.8%). The multivariate survival analysis revealed that being of Roma ethnicity is an independent risk factor for mortality (HR = 1.74; 95% CI = 1.04-2.91; P = 0.035).

CONCLUSIONS

Roma patients with ESRD initiate HD therapy at a younger age as compared to Caucasians. They have a higher 3 year mortality rate and are dying at a younger age. Roma ethnicity represents an independent risk factor for mortality in our cohort.

Race/Ethnicity and Cardiovascular Outcomes in Adults With CKD: Findings From the CRIC (Chronic Renal Insufficiency Cohort) and Hispanic CRIC Studies

BACKGROUND

Non-Hispanic blacks and Hispanics with end-stage renal disease have a lower risk for death than non-Hispanic whites, but data for racial/ethnic variation in cardiovascular outcomes for non-dialysis-dependent chronic kidney disease are limited.

STUDY DESIGN

Prospective cohort.

SETTING & PARTICIPANTS

3,785 adults with entry estimated glomerular filtration rates of 20 to 70mL/min/1.73m(2) enrolled in the CRIC (Chronic Renal Insufficiency Cohort) Study.

PREDICTORS

Race/ethnicity (non-Hispanic white, non-Hispanic black, and Hispanic).

OUTCOMES

Cardiovascular outcomes (atherosclerotic events [myocardial infarction, stroke, or peripheral arterial disease] and heart failure) and a composite of each cardiovascular outcome or all-cause death.

MEASUREMENTS

Multivariable Cox proportional hazards.

RESULTS

During a median follow-up of 6.6 years, we observed 506 atherosclerotic events, 551 heart failure events, and 692 deaths. In regression analyses, there were no significant differences in atherosclerotic events among the 3 racial/ethnic groups. In analyses stratified by clinical site, non-Hispanic blacks had a higher risk for heart failure events (HR, 1.59; 95% CI, 1.29-1.95), which became nonsignificant after adjustment for demographic factors and baseline kidney function. In contrast, Hispanics had similar risk for heart failure events as non-Hispanic whites. In analyses stratified by clinical site, compared with non-Hispanic whites, non-Hispanic blacks were at similar risk for atherosclerotic events or death. However, after further adjustment for cardiovascular risk factors, medications, and mineral metabolism markers, non-Hispanic blacks had 17% lower risk for the outcome (HR, 0.83; 95% CI, 0.69-0.99) than non-Hispanic whites, whereas there was no significant association with Hispanic ethnicity.

LIMITATIONS

Hispanics were largely recruited from a single center, and the study was underpowered to evaluate the association between Hispanic ethnicity and mortality.

CONCLUSIONS

There were no significant racial/ethnic differences in adjusted risk for atherosclerotic or heart failure outcomes. Future research is needed to better explain the reduced risk for atherosclerotic events or death in non-Hispanic blacks compared with non-Hispanic whites.

Relationship Between Age and Pre-End Stage Renal Disease Care in Elderly Patients Treated with Maintenance Hemodialysis

Receipt of pre-end stage renal disease (ESRD) clinical care can improve outcomes for patients treated with maintenance hemodialysis (HD). This study addressed age-related variations in receipt of a composite of recommended care to include nephrologist and dietician care, and use of an arteriovenous fistula at first outpatient maintenance HD. Less than 2% of patients treated with maintenance HD received all three forms of pre-ESRD care, and 63.3% received none of the three elements of care. The mean number of pre-ESRD care elements received by the oldest group (80 years and older) did not differ from the youngest group (less than 55 years), but was less than the 55 to 66 and 67 to 79 years groups; adjusted ratios of 0.93 (0.92 to 0.94; p < 0.001) and 0.94 (0.92 to 0.95; p < 0.001), respectively. A major effort is needed to ensure comprehensive pre-ESRD care for all patients with advanced chronic kidney disease (CKD), especially for the youngest and oldest patient groups, who were less likely to receive recommended pre-ESRD care.