US Dialysis Patients Research Articles

The Relationship of Age, Race, and Ethnicity with Survival in Dialysis Patients

Reports on the racial and ethnic differences in dialysis patient survival rates have been inconsistent. The literature suggests that these survival differences may be modified by age as well as categorizing white race as inclusive of Hispanic ethnicity. The goal of this study was to better understand these associations by examining survival among US dialysis patients by age, ethnicity, and race. Between 1995 and 2009, 1,282,201 incident dialysis patients ages 18 years or older were identified in the United States Renal Data System. Dialysis survival was compared among non-Hispanic blacks, non-Hispanic whites, and Hispanics overall and stratified by seven age groups. The median duration of follow-up was 22.3 months. Compared with non-Hispanic whites, a lower mortality risk was seen in Hispanics in all age groups. Consequently, when Hispanic patients were excluded from the white race, the mortality rates in white race all increased. Using non-Hispanic whites as the reference, a significantly lower mortality risk for non-Hispanic blacks was consistently observed in all age groups above 30 years (unadjusted hazard ratios ranged from 0.70 to 0.87; all P<0.001). In the 18- to 30-years age group, there remained an increased mortality risk in blacks versus non-Hispanic whites after adjustment for case mix (adjusted hazard ratio=1.19, 95% confidence interval=1.13-1.25). The mortality risk was lowest in Hispanics, intermediate in non-Hispanic blacks, and highest in non-Hispanic whites. This pattern generally holds in all age groups except for the 18- to 30-years group, where the adjusted mortality rate for non-Hispanic blacks exceeds the adjusted mortality rate of non-Hispanic whites.

Form CMS-2728 Data Versus Erythropoietin Claims Data: Implications for Quality of Care Studies

Medical Evidence Report Form CMS-2728 data is frequently used to study US dialysis patients, but the validity of these data have been called into question. We compared predialysis erythropoietin use as recorded on Form CMS-2728 with claims data as part of an assessment of quality of care among hemodialysis patients. Medicare claims were linked to Form CMS-2728 data for 18,870 patients. Dialysis patients, 67 years old or older, who started dialysis from 1 June 2005 to 31 May 2007 were eligible. Logistic and multivariate regressions were used to compare the use of either Form CMS-2728 or the corresponding claims data to predict mortality and the probability of meeting target hemoglobin levels. The sensitivity, specificity, and kappa coefficient for the predialysis erythropoietin indicator were 58.0%, 78.4%, and 0.36, respectively. Patients with a predialysis erythropoietin claim were less likely to die compared with patients without a claim (odds ratio = 0.80 and 95% confidence interval = 0.74–0.87), but there was no relationship observed between predialysis care and death using only Form CMS-2728 predictors. At the facility level, a predialysis erythropoietin claim was associated with a 0.085 increase in the rate of meeting target hemoglobin levels compared with patients without a claim (p = 0.041), but no statistically significant relationship was observed when using the Form CMS-2728 indicators. The agreement between Form CMS-2728 and claims data is poor and discordant results are observed when comparing the use of these data sources to predict health outcomes. Facilities with higher agreement between the two data sources may provide greater quality of care.

Comparing US and Chinese dialysis patients: an editorial on Cheng et al. Mortality rates among prevalent hemodialysis patients in Beijing: a comparison with USRDS data

Comparing US and Chinese dialysis patients: an editorial on Cheng et al. Mortality rates among prevalent hemodialysis patients in Beijing: a comparison with USRDS data

Hemodialysis Access Usage Patterns in the Incident Dialysis Year and Associated Catheter-Related Complications

Hemodialysis (HD) access is considered a critical and actionable determinant of morbidity, with a growing literature suggesting that initial HD access type is an important marker of long-term outcomes. Accordingly, we examined HD access during the incident dialysis period, focusing on infection risk and successful fistula creation during the first dialysis year. Longitudinal cohort. All US adults admitted to Fresenius Medical Care North America facilities within 15 days of first maintenance dialysis session between January 1 and December 31, 2007. Vascular access type at HD therapy initiation. Vascular access type at 90 days and at the end of the first year on HD therapy, bloodstream infection within the first year by access type, and catheter complication rate. Of 25,003 incident dialysis patients studied, 19,622 (78.5%) initiated dialysis with a catheter; 4,151 (16.6%), with a fistula; and 1,230 (4.9%), with a graft. At 90 days, 14,105 (69.7%) had a catheter, 4,432 (21.9%) had a fistula, and 1,705 (8.4%) had a graft. Functioning fistulas and grafts at dialysis therapy initiation had first-year failure rates of 10% and 15%, respectively. Grafts were seldom replaced by fistulas (3%), whereas 7,064 (47.6%) of all patients who initiated with a catheter alone still had only a catheter at 1 year. Overall, 3,327 (13.3%) patients had at least one positive blood culture during follow-up, with the risk being similar between the fistula and graft groups, but approximately 3-fold higher in patients with a catheter (P<0.001 for either comparison). Nearly 1 in 3 catheters (32.5%) will require tissue plasminogen activator use by a median of 41 days, with 59% requiring more than one tissue plasminogen activator administration. Potential underestimation of bacteremia because follow-up blood culture results did not include samples sent to local laboratories. In a large and representative population of incident US dialysis patients, catheter use remains very high during the first year of HD care and is associated with high mechanical complication and bloodstream infection rates.

Trends in the Incidence of Atrial Fibrillation in Older Patients Initiating Dialysis in the United States

One sixth of US dialysis patients 65 years of age have been diagnosed with atrial fibrillation/flutter (AF). Little is known, however, about the incidence of AF in this population. We identified 258 605 older patients (≥67 years of age) with fee-for-service Medicare initiating dialysis in 1995 to 2007, who had not been diagnosed with AF within the previous 2 years. Patients were followed for newly diagnosed AF. Multivariable proportional hazard regression was used to examine temporal trends and associations of race and ethnicity with incident AF. We also studied temporal trends in the mortality and risk of ischemic stroke after new AF. Over 514 395 person-years of follow-up, 76 252 patients experienced incident AF for a crude AF incidence rate of 148/1000 person-years. Incidence of AF increased by 11% (95% confidence interval, 5-16) from 1995 to 2007. Compared with non-Hispanic whites, blacks (-30%), Asians (-19%), Native Americans (-42%), and Hispanics (-29%) all had lower rates of incident AF. Mortality after incident AF decreased by 22% from 1995 to 2008. Even more pronounced reductions were seen for incident ischemic stroke during these years. The incidence of AF is high in older patients initiating dialysis in the United States and has been increasing over the 13 years of study. Mortality declined during that time but remained >50% during the first year after newly diagnosed AF. Because data on warfarin use were not available, we were unable to study whether trends toward better outcomes could be explained by higher rates of oral anticoagulation.

The Impact of Chronic Obstructive Pulmonary Disease and Smoking on Mortality and Kidney Transplantation in End-Stage Kidney Disease

Background: Chronic obstructive pulmonary disease (COPD) and tobacco use are leading causes of morbidity and mortality. The prevalence and clinical impact of COPD on mortality and kidney transplantation among patients who begin dialysis therapy is unclear. Methods: We explored the clinical impact of COPD and continued tobacco use on overall mortality and kidney transplantation in a national cohort study of US dialysis patients. National data on all dialysis patients (n = 769,984), incident between May 1995 and December 2004 and followed until October 31, 2006, were analyzed from the United States Renal Data System. Prevalence and period trends were determined while multivariable Cox regression evaluated relative hazard ratios (RR) for death and kidney transplantation. Results: The prevalence of COPD was 7.5% overall and increased from 6.7 to 8.1% from 1995–2004. COPD correlated significantly with older age, cardiovascular conditions, cancer, malnutrition, poor functional status, and tobacco use. Adjusted mortality risks were significantly higher for patients with COPD (RR = 1.20, 95% CI 1.18–1.21), especially among current smokers (RR = 1.28, 95% CI 1.25–1.32), and varied inversely with advancing age. In contrast, the adjusted risks of kidney transplantation were significantly lower for patients with COPD (RR = 0.47, 95% CI 0.41–0.54, for smokers and RR = 0.54, 95% CI 0.50–0.58, for non-smokers) than without COPD [RR = 0.72, 95% CI 0.70–0.75, for smokers and RR = 1.00 for non-smokers (referent category)]. Conclusions: Patients with COPD who begin dialysis therapy in the US experience higher mortality and lower rates of kidney transplantation, outcomes that are far worse among current smokers.

Dialysis at a Crossroads—Part II

A previous commentary pointed out that the renal community has led American healthcare in the development and continuous improvement of quality outcomes. However, survival, hospitalization, and quality of life for US dialysis patients is still not optimal. This follow-up commentary examines the obstacles, gaps, and metrics that characterize this unfortunate state of affairs. It posits that current paradigms are essential contributors to quality outcomes but are no longer sufficient to improve quality. New strategies are needed that arise from a preponderance of evidence, in addition to beyond a reasonable doubt standard. This work offers an action plan that consists of new pathways of care that will lead to improved survival, fewer hospitalizations and rehospitalizations, and better quality of life for patients undergoing dialysis therapy. Nephrologists in collaboration with large and small dialysis organizations and other stakeholders, including the Centers for Medicare and Medicaid Services, can implement these proposed new pathways of care and closely monitor their effectiveness. We suggest that our patients deserve nothing less and must receive even more.

Trends in the incidence of intestinal perforation in US dialysis patients (1992-2005)

Little is known about the incidence of intestinal perforation in patients undergoing dialysis. Concerns exist that sevelamer hydrochloride may increase the risk of intestinal perforation. We examined long-term trends for the incidence of intestinal perforation among US dialysis patients. We studied all dialysis patients (1992-2005) who had Medicare as primary payer. We used ICD-9 diagnosis code 569.83 to ascertain events of intestinal perforation. We studied (a) all perforations and (b) perforations that did not appear to be associated with specific causative conditions (specific diseases or iatrogenic procedures within 7 days of perforation). We used Poisson regression to model the annual number of intestinal perforations and tested for any changes in levels and temporal trends of incidence rates before versus after January 1, 1999. Overall, 1,060,132 patients contributed 2.7 million patient-years. We observed 12,355 events of intestinal perforation and 7,814 spontaneous perforations. The corresponding incidence rates were 4.6 (total) and 2.9 (spontaneous perforation) episodes per 1,000 person-years, respectively. For both outcome definitions, 30-day mortality was 42%. Unadjusted and adjusted incidence rates were not materially different over time. Formal tests for any changes in the level or slope of incidence comparing time periods before and after January 1, 1999, indicated no evidence for any changes in the incidence of intestinal perforation over time. In US dialysis patients, incidence of intestinal perforation was low, but associated with high short-term mortality. We did not detect any significant changes in the incidence of intestinal perforation before versus after approval of sevelamer hydrochloride in late 1998.

Altitude and the risk of cardiovascular events in incident US dialysis patients

Altitude is associated with all-cause mortality in US dialysis patients, but its association with cardiovascular outcomes has not been assessed. We hypothesized that higher altitude would be associated with lower rates of cardiovascular events due to an altered physiological response of dialysis patients to altitude induced hypoxia. We studied 984,265 patients who initiated dialysis from 1995 to 2006. Patients were stratified by the mean elevation of their residential zip codes and were followed from the start of dialysis to the occurrence of several validated cardiovascular endpoints: myocardial infarction, stroke, cardiovascular death and a composite of these end points. Incidence rate ratios across altitude strata were estimated using proportional hazards regression. All outcomes occurred less frequently among patients living at higher altitude compared with patients living at or near sea level, and the association appeared monotonic for all outcomes except for stroke, which was most incident in the 250-1999 ft group. Compared with otherwise similar patients residing at or near sea level, patients living at ≥ 6000 ft had 31% [95% confidence interval (CI): 21-41%] lower rates of myocardial infarction, 27% (95% CI: 15-37%) lower rates of stroke and 19% (95% CI: 14-24%) lower rates of cardiovascular death. Additional adjustment for biometric information did not materially change these findings. Effect modification between race and altitude was only consistently significant for Native Americans. Altitude did not significantly alter the rates of non-cardiovascular death. We conclude that dialysis patients at higher altitude experience lower rates of cardiovascular events compared to otherwise similar patients at lower altitude.

Insights into nephrologist training, clinical practice, and dialysis choice

There is variable emphasis on dialysis-specific training among US nephrology fellowship programs. Our study objective was to determine the association between nephrology training experience and subsequent clinical practice. We conducted a national survey of clinical nephrologists using a fax-back survey distributed between March 8, 2010 and April 30, 2010 (N = 629). The survey assessed the time distribution of clinical practice, self-assessment of preparedness to provide care for dialysis patients at the time of certification examination, distribution of dialysis modality among patients, and nephrologists' choice of dialysis modality for themselves if their kidneys failed. While respondents spent 28% of their time caring for dialysis patients, 38% recalled not feeling very well prepared to care for dialysis patients when taking the nephrology certification examination. Sixteen percent obtained additional dialysis training after fellowship completion. Only 8% of US dialysis patients use home dialysis; physicians very well prepared to care for dialysis patients at the time of certification or who obtained additional dialysis training were significantly more likely to provide care to home peritoneal dialysis patients. Even though 92% of US dialysis patients receive thrice weekly in-center hemodialysis, only 6% of nephrologists selected this for themselves; selection of therapy for self was associated with dialysis modalities used by their patients. Nephrology training programs need to ensure that all trainees are very well prepared to care for dialysis patients, as this is central to nephrology practice. Utilization of dialysis therapies other than standard hemodialysis is dependent, in part, on training experience.

More Frequent Hemoglobin Measurements and More Frequent Epoetin Alfa Titrations Are Both Associated with Increased Epoetin Alfa Dose but Not More Time in Target Hemoglobin Range,

Abstract 4194For the past 20 years, management of hemoglobin (Hb) level via erythropoiesis-stimulating agents (ESAs), such as epoetin alfa (EPO) has been the norm in the care of end-stage renal disease (ESRD) patients. Recently, questions about patient safety and new economic bundling rules have brought renewed focus on appropriate Hb targets and how they relate to the use of EPO. Important issues related to Hb control are the frequency of Hb measurements, Hb value, the frequency of changes in EPO dose (titrations), and total EPO dose. Current practice aims to achieve greater control of Hb by more frequent measurement and finer EPO dose titrations. No studies have definitively shown that levels of titration and measurement frequency lead to better clinical outcomes or more efficient use of EPO. One large retrospective analysis found increasing Hb measurements and EPO dose titration frequency decreased patient variability around the facility-level Hb mean (Khan et al, 2011). However, a second study found that frequent titrations have been shown to be the most important driver of Hb cycling—potentially dangerous large fluctuations in Hb levels (Fishbane and Berns, 2005). The issue remains controversial.We conducted a retrospective database analysis in order to quantify the frequency of Hb dose titrations and measurements, and to evaluate their relationship to ESA dose and the ability to keep patients within a Hb range of 10–12 g/dL. Data from prevalent (≥ 120 days), adult (>18 years old) hemodialysis patients dialyzing at DaVita dialysis clinics ≥ 3 times per week between January 1, 2009 and December 31, 2010 were included.For every session, patients’ stable dosing periods were defined as any series of at least 3 doses during which the dose did not change more than 10% from first dose in the series. Dose holds were defined as ≥ 3 consecutive sessions with 0 EPO dose. An EPO dose of 0 lasting <3 consecutive sessions was ignored when identifying stable periods and holds. Doses not categorized as part of a stable period or a dose hold were considered transition periods. A dose titration was defined as a difference of > 10% between any of the following: the mean dose of 2 consecutive stable periods; the mean dose of stable period and next/previous dose in transition period; and 2 consecutive doses within a transition period. Transitions involving a dose hold were counted as 1 titration if the patient then returned to a dose within 10% of the mean of the prior period; or 2 titrations otherwise. Similar rules were developed for the minority of patients who received EPO once or twice per week. Correlations among measures (titrations/patient-month and Hb measurements/patient-month with mean monthly EPO dose and time with Hb in range) were assessed using Pearson product-moment correlation and linear regression (adjusted for racial composition, percentage of dialysis vascular access types, percentage with comorbidities, and mean age, vintage, and BMI) at the physician and the facility levels. Time in range was defined as total patient time in range/total patient-time. Facility level analyses were weighted by facility load (minimum of 300 patient-months) and are reported here.Information from 81,464 patients at 1,336 facilities was assessed. The mean number of titrations was 13.6 ± 2.83 (mean ± SD) per patient per year and the mean number of Hb measurements was 36.3 ± 8.24 per patient per year. The mean percent of patient-time in range among these facilities was 57.1% ± 5.8%. At the facility level, after adjustment for case mix factors (mean age, vintage, and BMI at facility, access types, and racial composition) the annual number of dose titrations per patient and Hb measurements per patient were not associated with the percent of patient-months within a 10–12 g/dL Hb range (p=0.12 and p=0.47; respectively). An analysis of ESA utilization showed that an increase of 1 titration per patient at the facility level was associated with an extra 18,000 U (p<0.001) per patient.In this retrospective study of >80,000 US dialysis patients over 2 years, neither increased Hb measurements nor increased EPO titrations were associated with improving patient-time in Hb range. However, increased EPO titrations were associated with significantly increased EPO utilization. Although these associations do not demonstrate causality (or the direction of potential causality), they do underscore the need to assess titration practices. Disclosures:Bond:DaVita Clinical Research: Employment; Affymax Inc: Research presented in this study was paid for by Affymax. Rubin:DaVita Clinical Research: Employment; Affymax: The research presented in this abstract was paid for by Affymax. Wang:DaVita Clinical Research: Employment; Affymax: The research presented in this abstract was paid for by Affymax. Yang:Affymax: Employment.

Trends in Timing of Initiation of Chronic Dialysis in the United States

During the past decade, a trend has been observed in the United States toward initiation of chronic dialysis at higher levels of estimated glomerular filtration rate. This likely reflects secular trends in the composition of the dialysis population and a tendency toward initiation of dialysis earlier in the course of kidney disease. The goal of this study was to generate model-based estimates of the magnitude of changes in the timing of dialysis initiation between 1997 and 2007. We used information from a national registry for end-stage renal disease on estimated glomerular filtration rate at initiation among patients who received their first chronic dialysis treatment in 1997 or 2007. We used information regarding predialysis estimated glomerular filtration rate slope from an integrated health care system. After accounting for changes in the characteristics of new US dialysis patients from 1997 to 2007, we estimate that chronic dialysis was initiated a mean of 147 days earlier (95% confidence interval, 134-160) in the later compared with the earlier year. Differences in timing were consistent across a range of patient subgroups but were most pronounced for those aged 75 years or older; the mean difference in timing in that subgroup was 233 days (95% confidence interval, 206-267). Chronic dialysis appears to have been initiated substantially earlier in the course of kidney disease in 2007 compared with 1997. In the absence of strong evidence to suggest that earlier initiation of chronic dialysis is beneficial, these findings call for careful evaluation of contemporary dialysis initiation practices in the United States.

Survival Trends of US Dialysis Patients with Heart Failure

Congestive heart failure (CHF) is a major risk factor for death in end-stage kidney disease; however, data on prevalence and survival trends are limited. The objective of this study was to determine the prevalence and mortality effect of CHF in successive incident dialysis cohorts. This was a population-based cohort of incident US dialysis patients (n = 926,298) from 1995 to 2005. Age- and gender-specific prevalence of CHF was determined by incident year, whereas temporal trends in mortality were compared using multivariable Cox regression. The prevalence of CHF was significantly higher in women than men and in older than younger patients, but it did not change over time in men (range 28% to 33%) or women (range 33% to 36%). From 1995 to 2005, incident death rates decreased for younger men (≤70 years) and increased for older men (>70 years). For women, the pattern was similar but less impressive. During this period, the adjusted mortality risks (relative risk [RR]) from CHF decreased in men (from RR = 1.06 95% Confidence intervals (CI) 1.02-1.11 in 1995 to 0.91 95% CI 0.87-0.96 in 2005) and women (from RR = 1.06 95% CI 1.01-1.10 in 1995 to 0.90 95% CI 0.85-0.95 in 2005 compared with referent year 2000; RR = 1.00). The reduction in mortality over time was greater for younger than older patients (20% to 30% versus 5% to 10% decrease per decade). Although CHF remains a common condition at dialysis initiation, mortality risks in US patients have declined from 1995 to 2005.

Impact of race on hyperparathyroidism, mineral disarrays, administered vitamin D mimetic, and survival in hemodialysis patients.

Blacks have high rates of chronic kidney disease, are overrepresented among the US dialysis patients, have higher parathyroid hormone levels, but greater survival compared to nonblacks. We hypothesized that mineral and bone disorders (MBDs) have a bearing on survival advantages of black hemodialysis patients. In 139,328 thrice-weekly treated hemodialysis patients, including 32% blacks, in a large dialysis organization, where most laboratory values were measured monthly for up to 60 months (July 2001 to June 2006), we examined differences across races in measures of MBDs and survival predictabilities of these markers and administered the active vitamin D medication paricalcitol. Across each age increment, blacks had higher serum calcium and parathyroid hormone (PTH) levels and almost the same serum phosphorus and alkaline phosphatase levels and were more likely to receive injectable active vitamin D in the dialysis clinic, mostly paricalcitol, at higher doses than nonblacks. Racial differences existed in mortality predictabilities of different ranges of serum calcium, phosphorus, and PTH but not alkaline phosphatase. Blacks who received the highest dose of paricalcitol (>10 µg/week) had a demonstrable survival advantage over nonblacks (case-mix-adjusted death hazard ratio = 0.87, 95% confidence level 0.83–0.91) compared with those who received lower doses (<10 µg/week) or no active vitamin D. Hence, in black hemodialysis patients, hyperparathyroidism and hypercalcemia are more prevalent than in nonblacks, whereas hyperphosphatemia or hyperphosphatasemia are not. Survival advantages of blacks appear restricted to those receiving higher doses of active vitamin D. Examining the effect of MBD modulation on racial survival disparities of hemodialysis patients is warranted. © 2010 American Society for Bone and Mineral Research.

Review article: Hepatitis B and dialysis

The incidence of hepatitis B virus (HBV) infection in dialysis populations has declined over recent decades, largely because of improvements in infection control and widespread implementation of HBV vaccination. Regardless, outbreaks of infection continue to occur in dialysis units, and prevalence rates remain unacceptably high. For a variety of reasons, dialysis patients are at increased risk of acquiring HBV. They also demonstrate different disease manifestations compared with healthy individuals and are more likely to progress to chronic carriage. This paper will review the epidemiology, modes of transmission and diagnosis of HBV in this population. Prevention and treatment will be discussed, with a specific focus on strategies to improve vaccination response, new therapeutic options and selection of patients for therapy.

Education and End of Life in Chronic Kidney Disease

More than a half million patients are being treated for ESRD in the United States (1). Estimates suggest that more than 23 million people in the United States have earlier stage chronic kidney disease (CKD) (2). More than one third of US dialysis patients are black, a threefold overrepresentation (1,3–6). The mortality of dialysis patients with ESRD is approximately 21% annually (1). In contrast to the course of other chronic illnesses in the United States, black dialysis patients enjoy improved survival compared with white patients (1,5). This paradoxic difference is unexplained by socioeconomic status or currently identified biological factors. A reasonable hypothesis would suggest psychosocial factors underlie this dramatic disparity (7). A typical assertion in the introduction to many a press release, grant proposal, and article contains words to the effect that “the mortality rate of hemodialysis patients is unacceptably high.” For those who have served as health care workers since the 1970s, this type of statement must be taken with a grain of nephrologic salt. Before 1973, before the formulation of the administrative term “end-stage renal disease” (and before the genesis of “chronic kidney disease”), a diagnosis of uremia represented a death sentence for the patient (8,9). Enactment of a US federal entitlement for care for patients with ESRD allowed a large number of people to extend their lives, to perform useful employment, to participate in social activities, or to prepare for death. Those early, pioneering patients included few elderly patients or people with diabetes—techniques were too primitive to allow tolerable treatment for such individuals (or so it was thought). The institution of Medicare coverage removed many disparities in ESRD care (10). Since the enactment of HR-73, advances in dialytic technique, such as measurement of and increase in dosage of …

Changes in Hemoglobin Level Distribution in US Dialysis Patients From June 2006 to November 2008

Erythropoiesis-stimulating agents (ESAs) have had a positive effect on anemia treatment in dialysis patients. However, several events in recent years, including new clinical study results, ESA product label revisions, and coverage and reimbursement policy changes, have had an impact on ESA dosing patterns and consequently on hemoglobin (Hb) distribution characteristics in this patient population. Retrospective observational study using patient-level data from approximately 87% of dialysis centers in the United States. Dialysis patients who were receiving outpatient care at dialysis facilities during June 2006-November 2008 were included in this study. Recent events affecting ESA treatment practice patterns in US dialysis patients. Hb level distribution. Mean Hb level decreased by 0.37 g/dL during the indicated period. Additionally, standard deviation (SD) of the Hb level distribution decreased by 0.14 g/dL and skewness increased by -0.10. Hb measurements in specific ranges changed as follows: >12 g/dL, decreased by 11.3 percentage points;10-12 g/dL, increased by 9.4 percentage points; and <10 g/dL, increased by 1.9 percentage points. The percentage of patients with Hb level >13 g/dL for > or =3 months decreased by 2.9 percentage points. Potential bias in dialysis center selection and lack of information for patient characteristics. Recent events affecting ESA use in dialysis patients have had the desired effect of increasing the proportion of Hb measurements within the US Food and Drug Administration recommended target range of 10-12 g/dL and decreasing the proportion of Hb measurements >12 g/dL. However, the proportion of Hb measurements <10 g/dL also has increased. Benefits of a decrease in Hb measurements in the >12 g/dL range need to be considered, together with risks of having low Hb levels.

NON‐CORONARY HEART DISEASE IN DIALYSIS PATIENTS: Sudden Cardiac Death and Dialysis Patients

AbstractDialysis patients have extraordinarily high mortality rates. The death rate for all US dialysis patients in 2004 was 230 per 1000 patient‐years. Cardiac disease is the major cause of death in dialysis patients and accounts for 43% of all‐cause mortality. In the United States Renal Data System database 62% of cardiac deaths (or 27% of all deaths) are attributable to arrhythmic mechanisms. The estimated rate of sudden cardiac death in US dialysis patients in 2002 was 7% per year. There are several plausible explanations for the special vulnerability of dialysis patients to sustaining sudden cardiac death. Obstructive coronary artery disease, coupled with diminished tolerance to myocardial ischemia (in the setting of myocardial fibrosis and left ventricular hypertrophy), rapid electrolyte shifts in hemodialysis patients, and derangements in autonomic function may all contribute to this heightened risk of sudden cardiac death. This review focuses on the epidemiology of sudden cardiac death in dialysis patients, underlying mechanisms of sudden death, and potential interventions to reduce the risk of sudden cardiac death in dialysis patients (including medical therapy and defibrillators). It is unlikely that one single therapeutic intervention will prevent sudden cardiac death in dialysis patients; but a more modest (and attainable) goal is the implementation of multiple strategies to reduce the risk of sudden cardiac death in this special high‐risk population.

Educational Level as a Determinant of Access to and Outcomes After Kidney Transplantation in the United States

Disparities in access to kidney transplantation exist, yet few studies investigated educational level as a determinant of access to and outcomes after kidney transplantation. Prospective cohort study. Nationally representative sample of incident US dialysis patients, in which 3,245 patients reported their educational level. Educational level, categorized as some high school, high school graduate, some college, and college graduate. Access to kidney transplantation was defined as time from first dialysis treatment to: (1) the day of being wait-listed and (2) first kidney transplantation. Outcomes after kidney transplantation were: (3) all-cause mortality and graft failure ([4] all-cause and [5] death censored). Using Cox regression, we studied the relationship between predialysis educational level and access to and outcomes after kidney transplantation. During follow-up, 692 patients were wait-listed and 670 underwent kidney transplantation. Of those, 164 died and 241 lost their allograft (121 from nondeath causes). After multivariate adjustment, college graduates experienced 3 times greater rates of wait-listing (hazard ratio, 2.81; 95% confidence interval, 2.21 to 3.58) or kidney transplantation (hazard ratio, 3.06; 95% confidence interval, 2.38 to 3.92) compared with patients without a high school degree (P for trend across educational level for both outcomes < 0.001). Although mortality was not associated with educational level, increased rates of death-censored allograft loss were observed with less education (P for trend = 0.03). Not a randomized study. The latter finding is novel and important and requires confirmation. Its possible mechanisms (eg, adherence to immunosuppressants) warrant additional study.

Predialysis Nephrologist Care and Access to Kidney Transplantation in the United States

Predialysis nephrologist care is associated with morbidity and mortality in incident dialysis patients, but the relationship with access to kidney transplantation (KT) is unclear. From a national study of incident US dialysis patients, we identified 2253 patients with detailed information about predialysis care, sociodemographic characteristics and comorbidities. We used multivariate Cox proportional hazards models to study associations between predialysis nephrology care and two outcomes: time from first dialysis to the first day on the KT wait-list, and time to first KT. Two-thirds of patients first encountered a nephrologist >3 months prior to dialysis and one-third <or=3 months prior to dialysis (early vs. late nephrologist care; ENC vs. LNC). Overall, 515 patients were added to the KT wait-list and 406 underwent KT during follow-up (2.3 years). In multivariate analyses, ENC was associated with a 41% (95%CI: 15-72%) greater rate of being wait-listed compared to LNC and a 54% (95%CI: 22-96%) greater rate of KT. Similar associations existed with number of predialysis nephrology visits. Earlier and more frequent predialysis nephrologist care were associated with greater access to the KT wait-list as well as a higher rate of KT, indicating that LNC may augment existing inequalities that impair access to KT.