Racial differences in the delivery of hemodialysis

Trends in anemia at initiation of dialysis in the United States

BACKGROUND

Anemia almost invariably develops in patients with chronic renal insufficiency (CRI) and is associated with a wide range of complications. The anemia of CRI can be effectively treated with recombinant human erythropoietin (rHuEPO). Recent studies suggest that the management of anemia of CRI is suboptimal in the United States.

METHODS

We examined the trends in hematocrit and rHuEPO use among all patients who started chronic dialysis therapy between April 1, 1995, and December 31, 1999, from the End-stage Renal Disease Medical Evidence Form 2728 submitted to the Health Care Financing Administration of the United States. Follow-up data containing hematocrit levels after initiation were obtained from the Medicare Part A institutional outpatient dialysis provider claims for 1990 to 1998 prevalent patients.

RESULTS

From June 1995 to June 1999, the mean hematocrit at initiation of dialysis increased from 28.1 to 29.3%. Likewise, the annual percentage of patients receiving pre-dialysis rHuEPO increased from 21.8 to 28.1%. Patients receiving predialysis rHuEPO had a higher mean hematocrit than patients without predialysis rHuEPO. The annual percentage of patients with hematocrit <24% fell 6.6% and the percentage with hematocrit > or =30% increased 9.2%. The trend toward higher hematocrit levels has been consistent across all age, gender, and race categories. Older patients, males, whites, and those who selected peritoneal dialysis had higher hematocrit levels than their counterparts. There were significant geographic differences in the prevalence of predialysis rHuEPO use.

CONCLUSION

There has been a slight improvement in the management of anemia of CRI in the United States. However, a considerable fraction of patients still have hematocrit levels that are significantly lower than the currently recommended target. Furthermore, improvement in the management of anemia could result in improved clinical outcomes among patients with CRI.

Late initiation of dialysis among women and ethnic minorities in the United States

The ideal timing of initiation of renal replacement (RRT) therapy has been debated. It is currently recommended that RRT be instituted once the GFR falls below 10.5 ml/min per 1.73 m(2), unless edema-free body weight is stable or increased, the normalized protein nitrogen appearance rate is 0.8 g/kg per d or greater, and there are no clinical signs or symptoms of uremia. However, the mean estimated GFR at initiation of dialysis in the United States is 7.1 ml/min per 1.73 m(2). Factors that are associated with timing of initiation of dialysis in the United States are not clear. A cross-sectional study was performed to determine the factors that are associated with late initiation of dialysis as defined by GFR at initiation of less than 5 ml/min per 1.73 m(2) among patients who began dialysis in the United States between 1995 and 1997. Data were obtained from the U.S. Renal Data System, and GFR was estimated using the formula derived from the Modification of Diet in Renal Disease Study. Twenty-three percent of patients started dialysis late. In the multivariate analysis, women (odds ratio [OR] = 1.70), Hispanics and Asians (OR = 1.47 and 1.66, respectively, compared with Caucasians), uninsured patients (OR = 1.55 compared with private insurance), and employed patients (OR = 1.20) were more likely to start dialysis late. Patients with diabetes, cardiac disease, peripheral vascular disease, and poor functional status were less likely to start dialysis late compared with patients without these comorbid conditions. Certain nonclinical patient characteristics, notably female gender, race, and lack of insurance, are related to an increased likelihood of late initiation of dialysis. These factors may reflect reduced access to care. Additional studies are indicated to determine the potential impact of reduced access to care and whether late initiation of dialysis results in adverse clinical and economic outcomes among patients with end-stage renal disease in the United States.

Patient race and decisions to withhold or withdraw life-sustaining treatments for seriously ill hospitalized adults. SUPPORT Investigators. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments

PURPOSE

Patient race is associated with decreased resource use for seriously ill hospitalized adults. We studied whether this difference in resource use can be attributed to more frequent or earlier decisions to withhold or withdraw life-sustaining therapies.

SUBJECTS AND METHODS

We studied adults with one of nine illnesses that are associated with an average 6-month mortality of 50% who were hospitalized at five geographically diverse teaching hospitals participating in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT). We examined the presence and timing of decisions to withhold or withdraw ventilator support and dialysis, and decisions to withhold surgery. Analyses were adjusted for demographic characteristics, prognosis, severity of illness, function, and patients' preferences for life-extending care.

RESULTS

The mean (+/- SD) age of the patients was 63 +/- 16 years; 16% were African-American, 44% were women, and 53% survived for 6 months or longer. Of the 9,076 patients, 5,349 (59%) had chart documentation that ventilator support had been considered in the event the patient's condition required such a treatment to sustain life, 2,975 charts (33%) had documentation regarding major surgery, and 1,293 (14%) had documentation of discussions about dialysis. There were no significant differences in the unadjusted rates of decisions to withhold or withdraw treatment among African-Americans compared with non-African-Americans: among African-Americans, 33% had a decision made to withhold or withdraw ventilator support compared with 35% among other patients, 14% had a decision made to withhold major surgery compared with 12% among other patients, and 25% had a decision made to withhold or withdraw dialysis compared with 30% among other patients (P >0.05 for all comparisons). After adjustment for demographic characteristics, prognosis, illness severity, function, and preferences for care, there were no differences in the timing or rate of decisions to withhold or withdraw treatments among African-Americans compared with non-African-American patients.

CONCLUSION

Patient race does not appear to be associated with decisions to withhold or withdraw ventilator support or dialysis, or to withhold major surgery, in seriously ill hospitalized adults.

Does the survival advantage of nonwhite dialysis patients persist after case mix adjustment?

PURPOSE

Nonwhite dialysis patients survive longer than white patients; however, their clinical characteristics differ. We examined whether case mix differences explain the apparent survival advantage of nonwhite dialysis patients.

SUBJECTS AND METHODS

We performed a prospective cohort study using data from the US Renal Data System Case Mix Severity Study that included 4,797 randomly selected dialysis patients 20 years of age and older who were followed up for up to 6 years. Demographic, comorbidity, laboratory, nutritional, and functional status data were obtained. Multivariable proportional hazards models adjusted for case mix differences between nonwhite and white dialysis patients. Additional analyses examined the effects of differences in transplantation rates, withdrawal from dialysis rates, and treatment modality selection.

RESULTS

Unadjusted survival rates of black, Native American, and Asian or Pacific Islander dialysis patients were similar, and better than that for white dialysis patients. Relative to whites, the unadjusted relative risk (RR) for mortality among nonwhite patients was 0.64 (95% confidence interval [CI]: 0.58 to 0.70). Adjustment for case mix reduced, but did not eliminate, the survival advantage associated with nonwhite race (RR = 0.78, CI: 0.71 to 0.86). Adjustment for differences in transplantation rates (RR = 0.83, CI: 0.75 to 0.91), withdrawal from dialysis rates (RR = 0.81, CI: 0.73 to 0.90), and initial treatment modality (RR = 0.79, CI: 0.71 to 0.87) did not explain the lower mortality among nonwhites.

CONCLUSIONS

A survival advantage for nonwhite dialysis patients persists after case mix adjustment. Future studies should explore additional physiologic and socioeconomic factors that might explain this difference.

Is peritoneal dialysis a good option for black patients?

Blacks are less likely than whites to use peritoneal dialysis (PD) as the initial renal replacement therapy. The reason for the underusage of PD by blacks is unknown. In a cross-sectional multicenter trial, we studied peritoneal transport character, small-molecular-weight solute clearances, and nutritional status in 475 patients undergoing PD (168 whites, 192 blacks, and 115 Asians). The mean age of blacks undergoing PD was significantly younger than that of whites (47.6 +/- 14.7 v 58.2 +/- 16.7 years; P < 0.0001). Target Kt/V and weekly creatinine clearance (WCC) as defined by the Dialysis Outcome Quality Initiative Work Group was achieved by 62.5% of whites, 67.2% of blacks, and 54.8% of Asians (P = 0.05). Total protein (7.25 +/- 0.88 v 6.55 +/- 0.73 g/dL), albumin (3.72 +/- 0.57 v 3.55 +/- 0.53 g/dL), and lean body mass (LBM; 41.7 +/- 15.6 v 33.0 +/- 11.8 kg) were lower in whites compared with blacks (P < 0.001). Although the normalized protein catabolic rate (nPCR) was greater (0.82 +/- 0.24 v 0.90 +/- 0.32 g/kg/d; P = 0.04), total protein (6.24 +/- 0.85 g/dL) and serum albumin levels (3.36 +/- 0.52 g/dL) and LBM (30.1 +/- 8.0 kg) were significantly lower in Asians than blacks (P < 0.0001). The favorable anabolic response in blacks may partially be explained by a higher calorie intake in this group of patients (29.6 +/- 10.7 Cal/kg/d) compared with whites (22.4 +/- 6.8 Cal/kg/d) and Asians (23.9 +/- 9.8 Cal/kg/d; P = 0.03). Multiple regression analysis identified that black race and weight were positively associated, whereas dialysate/plasma creatinine ratio (D/P(Creat)) and age had a negative effect on serum albumin level. Follow-up data indicated that the Kt/V (2.09 +/- 0.50 v 2.39 +/- 0.56; P = 0.02) and WCC (60.8 +/- 4.3 v 70.2 +/- 7.3 L/1.73 m2; P = 0.02) increased significantly from baseline only in blacks. We conclude that PD is an ideal renal replacement therapy in at least a subset of blacks with end-stage renal disease.

Hemodialysis adequacy in Network 5: disparity between states and the role of center effects

The purpose of this study was to determine whether an observed difference in hemodialysis adequacy between states in Network 5 was due to variations in patient characteristics and to what extent dialysis center effects played a role in the observed disparity between states. This was a retrospective observational study of 6,969 patients dialyzed at centers in Maryland and Virginia. There were 3,919 patients on hemodialysis at 89 facilities in Virginia and 3,050 subjects dialyzed at 65 centers in Maryland. The mean urea reduction ratio (URR) was higher in Virginia compared with Maryland (68.2 +/- 0.1% v 66.0 +/- 0.2%, P < 0.0001, respectively), and there continued to be a mean difference in URR of 1.8% between VA and MD (P < 0.0001) after adjusting for several covariates. The differences in URR between states varied depending on facility proprietary status, size as measured by number of stations, and relationship to hospital (free-standing or hospital-based). Furthermore, the center where a patient dialyzed, when treated as a fixed effect, accounted for 15% of the variance in URR. The mean difference of 1.8% in URR between states persisted in a mixed-effects model that included all covariates along with adjusting for dialysis centers as a random effect. The disparity in dialysis adequacy between states in Network 5 could not be accounted for by demographic characteristics, case mix factors, or a large center effect observed in the region. Therefore, we conclude that underlying national reports on dialysis adequacy are heterogeneous results related to differences across regions such as states within a given Network. This difference between states is not explained by the strong center effect found on adequacy in this population of hemodialysis patients.

Improvement in adequacy of delivered dialysis for adult in-center hemodialysis patients in the United States, 1993 to 1995

The objective of this review is to describe the adequacy of delivered dialysis provided to in-center hemodialysis patients in the United States and to compare the findings with published guidelines. The medical records of random samples of 6,138, 6,919, and 6,861 patients in hemodialysis facilities were studied from all Medicare-eligible adult in-center hemodialysis patients alive on December 31, 1993, 1994, and 1995, respectively. The main clinical measure used was the urea reduction ratio (URR), the mean of which was 0.63 in 1993, 0.64 in 1994, and 0.66 in 1995. The proportion of patients with URR > or = 0.65, as recommended by the Renal Physicians Association and a National Institutes of Health Consensus Development Conference Statement, increased from 43% in 1993 to 49% in 1994 and 59% in 1995. In each of these 3 years, women were more likely than men to have a URR > or = 0.65 (1993: 54% v 31%, odds ratio 2.6; 1994: 61% v 38%, odds ratio 2.5; and 1995: 70% v 50%, odds ratio 24), as were older patients (65+ years) compared with younger patients (18 to 44 years) (1993: 47% v 37%, odds ratio 1.4; 1994: 54% v 45%, odds ratio 1.5; and 1995: 65% v 53%, odds ratio 1.6) and white patients compared with black patients (1993: 46% v 36%, odds ratio 1.5; 1994: 53% v 43%, odds ratio 1.5; and 1995: 63% v 54%, odds ratio 1.4). There was also substantial geographic variation in the proportion of patients receiving hemodialysis with a URR > or = 0.65. In conclusion, marked differences existed in 1993, 1994, and 1995 between observed practice and consensus guidelines for the delivery of adequate dialysis. Nevertheless, notable improvement occurred during this time period. A system to monitor further improvements in hemodialysis care in the United States is in place.

African-Americans on maintenance dialysis: a review of racial differences in incidence, treatment, and survival

African-Americans are the fasting growing racial minority with end stage renal disease (ESRD) in the United States. Currently, African-Americans comprise approximately 31% of the ESRD population. African-Americans are almost a decade younger than their white (referring to non-Hispanic white) counterparts with ESRD with a mean age of 58 years old. Although African-Americans systematically receive less dialysis than whites (Kt/V of 1.05 versus 1.18, respectively), their survival is higher. The 2-year survival probability of African-Americans is 66.2% in comparison with 59.8% for whites. This improved survival with ESRD is accompanied by an improved quality of life for African-Americans. Their enhanced quality of life is reflected by a greatly decreased frequency of withdrawing from dialysis treatments. In this article, we will examine the reasons why African-Americans have an excessive incidence of selective diseases that culminate in ESRD. We will explore the factors that influence the difference in dialysis modality selection between African-Americans and whites. Lastly, we will pose and judge several hypotheses that may account for the improved survival enjoyed by African-Americans with ESRD. We contend that research to clarify the basis for these differences between African-Americans and whites with ESRD will improve outcomes for both populations and is fiscally sound health policy.

Measuring, managing, and improving the quality of end-stage renal disease care

As the federal end-stage renal disease (ESRD) program enters its third decade, it continues to grow both in terms of patient enrollment and cost. High visibility as well as patient, physician, and societal concerns regarding ESRD treatment outcomes and expenditures make the development of improved and expanded quality assurance and improvement (QA/QI) mechanisms for the ESRD program vital. The purpose of a QA/QI program is to identify and apply techniques for assessing and improving ESRD care quality to achieve the best possible outcome for all patients who can benefit medically, within the expenditure constraints set by society. Current QA knowledge and methods are reviewed in this article and are judged to be useful but of limited value. Limitations of current quality assessment tools, provider resistance, and inadequate governmental support are substantial barriers to implementation of a QA program. An ESRD QA/QI program should develop improved QA tools at the same time that available tools are cautiously put to work. Such a program would be based in individual treatment units, using existing network and US Renal Data System structures and a new national ESRD QA committee for support and oversight. As additional ESRD QA data become available, providers would incorporate the new information into decision making at all levels to enhance patient outcome. Substantial financial support from the government will be needed to implement such a quality program. A comprehensive ESRD QA program could serve as a model for QA for the national health care system.