Outcomes for Adolescent Hispanic Hemodialysis Patients: Findings From the ESRD Clinical Performance Measures Project

Influence of vascular access type on sex and ethnicity-related mortality in hemodialysis-dependent patients

OBJECTIVES

To determine whether sex- and ethnicity-based mortality differences in patients dependent on hemodialysis (hemodialysis patients) are because of prevalence of vascular access type.

METHODS

Southern California Permanente Medical Group Renal Database, which contained 5821 chronic hemodialysis patients between 2000 and 2008, was studied.

RESULTS

Mean age of the patients was 62 years, and 59% were male. Of the population, 33% were white; 32%, Hispanic; 23%, African American; 9%, Asian/Pacific Islander; and 3%, other race or ethnicity. Predominant access type over the course of the study was arteriovenous fistula (AVF) in 73%, arteriovenous graft (AVG) in 12%, and tunneled catheter in 14%. There was a higher percentage of AVF in whites (71%) than in African Americans (63%). Risk of death was independently increased by age (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.04-1.05), male sex (HR, 1.33; 95% CI, 1.22-1.45), diabetes (HR, 1.22; 95% CI, 1.12-1.33), use of an AVG (HR, 1.51; 95% CI, 1.34-1.71) or a tunneled catheter (HR, 6.45; 95% CI, 5.78-7.20). Compared with whites, African-American race decreased the risk of death (HR, 0.63; 95% CI, 0.56-0.70), as did Asian/Pacific Islander (HR, 0.58; 95% CI, 0.49-0.69), Hispanic (HR, 0.58; 95% CI, 0.51-0.65), and other race (HR, 0.67; 95% CI, 0.52-0.86).

CONCLUSION

Age, sex, race or ethnicity, access type, and diabetes are independent risk factors for mortality in hemodialysis patients. After controlling for potential confounders, when compared with whites, minorities all demonstrate significantly decreased risk of mortality. African Americans had reduced mortality risk despite a lower prevalence of arteriovenous fistula compared with whites. Male sex increased mortality. Differences in mortality between sexes and ethnicities in this population cannot be accounted for by differences in type of dialysis access.

Sex, race, and socioeconomic disparities in kidney disease in children

Racial and gender differences in the prevalence and treatment of chronic kidney disease in US children have been reported. Girls have lower rates of kidney transplantation than boys. Incidence of end-stage renal disease is twice as high among black patients compared with whites. African Americans are less likely than white patients to achieve hemoglobin targets on dialysis, are more likely to be treated with hemodialysis, and to wait longer for a transplant. Reasons for these disparities in disease burden and treatment choices are not known, but possible causes include genetic factors and socioeconomic and sociocultural influences on accessing medical care.

Hemoglobin differences by race in children with CKD

BACKGROUND

There are known racial disparities in the prevalence of anemia in adults with chronic kidney disease (CKD), but these differences have not been well described in children.

STUDY DESIGN

Cohort study, cross-sectional analysis.

SETTING & PARTICIPANTS

The Chronic Kidney Disease in Children (CKiD) Study is a multicenter prospective cohort study of children with mild to moderate CKD. This analysis included 429 children of African American or white race.

PREDICTOR

Race.

OUTCOMES & MEASUREMENTS

This study examined the association of race with hemoglobin level. Both multiple linear regression and generalized gamma modeling techniques were used to characterize the association between race and hemoglobin level.

RESULTS

79% of the cohort was white, 21% was African American. Neither median hemoglobin level nor frequency of erythropoiesis-stimulating agent use differed by race. In multivariate analysis, lower levels of iohexol-measured glomerular filtration rate, African American race, and glomerular disease (vs nonglomerular disease) as the underlying cause of CKD were independently associated with decreased hemoglobin levels; independent of glomerular filtration rate and CKD diagnosis, African American children had average hemoglobin levels that were 0.6 g/dL (95% CI, -0.9 to -0.2 g/dL) lower than those of white children. Generalized gamma modeling showed that differences in hemoglobin levels observed by race become more pronounced when moving from high to low in the overall hemoglobin level distribution.

LIMITATIONS

Cross-sectional analysis cannot establish causality, and data for iron stores were not available for all patients.

CONCLUSIONS

African American compared with white children have lower hemoglobin values in CKD independent of the underlying cause of CKD. These racial differences in hemoglobin levels appear to increase at the lower end of the hemoglobin level distribution in this population.

Differences in mortality among Mexican-American, Puerto Rican, and Cuban-American dialysis patients in the United States

BACKGROUND

The Hispanic ethnic group is heterogeneous, with distinct genetic, cultural, and socioeconomic characteristics, but most prior studies of patients with end-stage renal disease focus on the overall Hispanic ethnic group without further granularity. We examined survival differences among Mexican-American, Puerto Rican, and Cuban-American dialysis patients in the United States.

STUDY DESIGN

Prospective observational study.

SETTING & PARTICIPANTS

Data from individuals randomly selected for the End-Stage Renal Disease Clinical Performance Measures Project (2001 to 2005) were examined. Mexican-American (n = 2,742), Puerto Rican (n = 838), Cuban-American (n = 145), and Hispanic-other dialysis patients (n = 942) were compared with each other and with non-Hispanic (n = 33,076) dialysis patients in the United States.

PREDICTORS

Patient characteristics of interest included ethnicity/race, comorbidities, and specific available laboratory values.

OUTCOMES

The major outcome of interest was mortality.

RESULTS

In the fully adjusted multivariable model, 2-year mortality risk was significantly lower for the Mexican-American and Hispanic-other groups compared with non-Hispanics (adjusted hazard ratio, 0.79; 95% confidence interval, 0.73 to 0.85; adjusted hazard ratio, 0.81; 95% confidence interval, 0.71 to 0.92, respectively). Differences in 2-year mortality rates within the Hispanic ethnic groups were statistically significant (P = 0.004) and ranged from 21% lower mortality in Mexican Americans to 3% higher mortality in Puerto Ricans compared with non-Hispanics.

LIMITATIONS

Include those inherent to an observational study, potential ethnic group misclassification, and small sample sizes for some Hispanic subgroups.

CONCLUSION

Mexican-American and Hispanic-other dialysis patients have a survival advantage compared with non-Hispanics. Furthermore, Mexican Americans, Cuban Americans, and Hispanic others had a survival advantage compared with their Puerto Rican counterparts. Future research should continue to examine subgroups within Hispanic ethnicity to understand underlying reasons for observed differences that may be masked by examining the Hispanic ethnic group as only a single entity.

Ethnic disparity in outcomes for pediatric peritoneal dialysis patients in the ESRD Clinical Performance Measures Project

Ethnicity information was collected for all pediatric peritoneal dialysis patients from the End-Stage Renal Disease (ESRD) Clinical Performance Measures (CPM) Project for the period October 2004 through March 2005. Associations between intermediate outcomes and Hispanic ethnicity were determined. Thirty percent (207/696) of patients in the final cohort were Hispanic, 24% (165/696) non-Hispanic black, and 46% (324/696) non-Hispanic white. Hispanics were more likely to be female, older, and have a lower mean height standard deviation score (SDS). There were no significant differences among ethnic/racial groups regarding clearance parameters. More Hispanics had a mean hemoglobin > or = 11 g/dl compared with non-Hispanic blacks and non-Hispanic whites (77% vs. 55% and 70%, P < 0.0001). More Hispanics compared with non-Hispanic blacks and non-Hispanic whites had a mean serum albumin > or = 4.0/3.7 g/dl [bromcresol green/bromcresol purple laboratory method (BCG/BCP)] (50% vs. 24% and 27%, respectively, P < 0.0001). In multivariate analyses, Hispanics remained significantly more likely to achieve a mean serum albumin > or = 4.0/3.7 g/dl (BCG/BCP) compared with non-Hispanic whites (referent) and were as likely to achieve clearance and hemoglobin targets. Pediatric Hispanic peritoneal dialysis patients experience equivalent or better intermediate outcomes of dialytic care compared with non-Hispanics. Further study is needed to understand associations of Hispanic ethnicity with outcomes such as hospitalization, transplantation, and mortality.