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Papers by Philip Held

Research paper thumbnail of Longitudinal assessment of mortality risk among candidates for liver transplantation

Liver Transplantation, 2003

Liver allocation policy recently was modified to use the Model for End-Stage Liver Disease (MELD)... more Liver allocation policy recently was modified to use the Model for End-Stage Liver Disease (MELD) for patients with chronic liver disease to stratify potential recipients according to risk for waitlist death. In this study, a retrospective cohort of 760 adult patients with chronic liver disease placed on the liver transplant waitlist between January 1995 and March 2001 and followed up for up to 74 months was studied to assess the ability of the MELD to predict mortality among waitlisted candidates and evaluate the prognostic importance of changes in MELD score over time. Serial MELD scores predicted waitlist mortality significantly better than baseline MELD scores or medical urgency status. Each unit of the 40-point MELD score was associated with a 22% increased risk for waitlist death (P C .001), whereas medical urgency status was not a significant independent predictor. For any given MELD score, the magnitude and direction of change in MELD score during the previous 30 days (AMELD) was a significant independent mortality predictor. Patients with MELD score increases greater than 5 points over 30 days had a threefold greater waitlist mortality risk than those for whom MELD scores increased more gradually (P < .0001). We conclude that mortality risk on the liver transplant waitlist is predicted more accurately by serial MELD score determinations than by medical urgency status or single MELD measurements. AMELD score over time reflects progression of liver disease and conveys important additional prognostic information that should be considered in the further evolution of national liver allocation policy. (Liver TranspZ2003;9:12-18.)

Research paper thumbnail of Evaluation of the ESRD managed care demonstration operations

Health care financing review, 2003

Individuals with end stage renal disease (ESRD), most of whom are insured by Medicare, are genera... more Individuals with end stage renal disease (ESRD), most of whom are insured by Medicare, are generally prohibited from enrolling in Medicare managed care plans (MCPs). CMS offered ESRD patients the opportunity to participate in an ESRD managed care demonstration mandated by Congress. The demonstration tested whether managed care systems would be of interest to ESRD patients and whether these approaches would be operationally feasible and efficient for treating ESRD patients. This article examines the structure, implementation, and operational outcomes of the three demonstration sites, focusing on: the structure of these managed care programs for ESRD patients, requirements needed to attract and enroll patients, and the challenges of introducing managed care programs in the ESRD arena.

Research paper thumbnail of ESRD managed care demonstration: financial implications

Health care financing review, 2003

In 1996, CMS launched the end stage renal disease (ESRD) managed care demonstration to study the ... more In 1996, CMS launched the end stage renal disease (ESRD) managed care demonstration to study the experience of offering managed care to ESRD patients. This article analyzes the financial impact of the demonstration, which sought to assess its economic impact on the Federal Government, the sites, and the ESRD Medicare beneficiaries. Medicare's costs for demonstration enrollees were greater than they would have been if these enrollees had remained in the fee-for-service (FFS) system. This loss was driven by the lower than average predicted Medicare spending given the demonstration patients' conditions. The sites experienced losses or only modest gains, primarily because they provided a larger benefit package than traditional Medicare coverage, including no patient obligations and other benefits, especially prescription drugs. Patient financial benefits were approximately $9,000 annually.

Research paper thumbnail of Trends in Cost Attributable to Kidney Transplantation Evaluation and Waiting List Management in the United States, 2012-2017

JAMA Network Open

IMPORTANCE While recent policy reforms aim to improve access to kidney transplantation for patien... more IMPORTANCE While recent policy reforms aim to improve access to kidney transplantation for patients with end-stage kidney disease, the cost implications of kidney waiting list expansion are not well understood. The Organ Acquisition Cost Center (OACC) is the mechanism by which Medicare reimburses kidney transplantation programs, at cost, for costs attributable to kidney transplantation evaluation and waiting list management, but these costs have not been well described to date. OBJECTIVES To describe temporal trends in mean OACC costs per kidney transplantation and to identify factors most associated with cost. DESIGN, SETTING, AND PARTICIPANTS This economic evaluation included all kidney transplantation waiting list candidates and recipients in the United States from 2012 to 2017. A population-based study of cost center reports was conducted using data from all Center of Medicare & Medicaid-certified transplantation hospitals. Data analysis was conducted from June to August 2021. EXPOSURES Year, local price index, transplantation and waiting list volume of transplantation program, and comorbidity burden. MAIN OUTCOMES AND MEASURES Mean OACC costs per kidney transplantation.

Research paper thumbnail of The Terrible Toll of the Kidney Shortage

Journal of the American Society of Nephrology, 2018

Research paper thumbnail of Quality of life and patient satisfaction: ESRD managed care demonstration

Health care financing review, 2003

To study the effects of managed care on dialysis patients, we compared the quality of life and pa... more To study the effects of managed care on dialysis patients, we compared the quality of life and patient satisfaction of patients in a managed care demonstration with three comparison samples: fee-for-service (FFS) patients, managed care patients outside the demonstration, and patients in a separate national study. Managed care patients were less satisfied than FFS patients about access to health care providers, but more satisfied with the financial benefits (copayment coverage, prescription drugs, and nutritional supplements) provided under the demonstration managed care plan (MCP). After 1 year in the demonstration, patients exhibited statistically and clinically significant increases in quality of life scores.

Research paper thumbnail of Chronic Renal Failure after Transplantation of a Nonrenal Organ

New England Journal of Medicine, 2003

Transplantation of nonrenal organs is often complicated by chronic renal disease with multifactor... more Transplantation of nonrenal organs is often complicated by chronic renal disease with multifactorial causes. We conducted a population-based cohort analysis to evaluate the incidence of chronic renal failure, risk factors for it, and the associated hazard of death in recipients of nonrenal transplants. methods Pretransplantation and post-transplantation clinical variables and data from a registry of patients with end-stage renal disease (ESRD) were linked in order to estimate the cumulative incidence of chronic renal failure (defined as a glomerular filtration rate of 29 ml per minute per 1.73 m 2 of body-surface area or less or the development of ESRD) and the associated risk of death among 69,321 persons who received nonrenal transplants in the United States between 1990 and 2000. results During a median follow-up of 36 months, chronic renal failure developed in 11,426 patients (16.5 percent). Of these patients, 3297 (28.9 percent) required maintenance dialysis or renal transplantation. The five-year risk of chronic renal failure varied according to the type of organ transplanted-from 6.9 percent among recipients of heart-lung transplants to 21.3 percent among recipients of intestine transplants. Multivariate analysis indicated that an increased risk of chronic renal failure was associated with increasing age (relative risk per 10-year increment, 1.36; P<0.001), female sex (relative risk among male patients as compared with female patients, 0.74; P<0.001), pretransplantation hepatitis C infection (relative risk, 1.15; P<0.001), hypertension (relative risk, 1.18; P<0.001), diabetes mellitus (relative risk, 1.42; P<0.001), and postoperative acute renal failure (relative risk, 2.13; P<0.001). The occurrence of chronic renal failure significantly increased the risk of death (relative risk, 4.55; P<0.001). Treatment of ESRD with kidney transplantation was associated with a five-year risk of death that was significantly lower than that associated with dialysis (relative risk, 0.56; P=0.02). conclusions The five-year risk of chronic renal failure after transplantation of a nonrenal organ ranges from 7 to 21 percent, depending on the type of organ transplanted. The occurrence of chronic renal failure among patients with a nonrenal transplant is associated with an increase by a factor of more than four in the risk of death.

Research paper thumbnail of Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization rates to national rates

Kidney International, 1996

Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization ra... more Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization rates to national rates. Hospitalization tables of the U.S. Renal Data System allow description of national hospitalization rates among incident and prevalent dialysis patients in five-year age groups. These rates are further stratified by sex, race, and four primary disease categories. Based on these tables derived from the data on over 250,000 incident and prevalent patients during 1991 to 1993, a methodology is described that allows comparison of local (for example, dialysis facility) or regional "first admission" rates among incident and prevalent dialysis patients to the national rates. A standardized hospitalization ratio is introduced to facilitate such comparisons, and methods for assessing statistical significance are discussed. Since this methodology allows adjustment for age, race, sex, and primary disease, it can serve as useful tool for dialysis research. It can also be used at the dialysis facility level, alone or in conjunction with the standardized mortality ratio, to facilitate local quality assurance. The U.S. Renal Data System (USRDS) maintains a vast database of information on the end-stage renal disease (ESRD) population of the United States. The primary source of USRDS data is the Health Care Financing Administration (HCFA), and consists primarily of information on patients who are in the Medicare system. It is estimated that the data encompass 93% of all ESRD patients. The data are updated and summarized yearly in the reference tables of the USRDS Annual Data Report. The wealth of information available from the USRDS can be put to use in a variety of valuable ways. The intent of this article is to show how information on patient hospitalization can be used in a simple way to construct a standardized hospitalization ratio (SHR). The SHR is derived in a similar manner to the standardized mortality ratio (SMR) proposed in Wolfe et al [1], and should prove valuable to dialysis facilities interested in comparing their local hospitalization experience to the national norm. Wolfe et a! [1] describe a methodology for comparing the observed mortality rate in a specific group of ESRD patients to national average rates, adjusted for age, race, and primary cause of ESRD. The national rates are calculated based on the reference tables found in the 1990 USRDSAnnua1 Data Report [2]. The

Research paper thumbnail of Comparison of mortality with home hemodialysis and center hemodialysis: A national study

Kidney International, 1996

Comparison of mortality with home hemodialysis and center hemodialysis: A national study. We soug... more Comparison of mortality with home hemodialysis and center hemodialysis: A national study. We sought to determine whether lower mortality rates reported with hemodialysis (HD) at home compared to hemodialysis in dialysis centers (center HD) could be explained by patient selection. Data are from the United States Renal Data System (USRDS) Special Study Of Case Mix Severity, a random national sample of 4,892 patients who started renal replacement therapy in 1986 to 1987. Intent-to-treat analyses compared mortality between home HD (N = 70) and center HD patients (N = 3,102) using the Cox proportional hazards model. Home HD patients were younger and had a lower frequency of comorbid conditions. The unadjusted relative risk (RR) of death for home HD patients compared to center HD was 0.37 (P < 0.001). The RR adjusted for age, sex, race and diabetes, was 44% lower in home HD patients (RR = 0.56, P = 0.02). When additionally adjusted for comorbid conditions, this RR increased marginally (RR = 0.58, P = 0.03). A different analysis using national USRDS data from 1986/7 and without comorbid adjustment showed patients with training for self care hemodialysis at home or in a center (N = 418) had a lower mortality risk (RR = 0.78, P = 0.001) than center HD patients (N = 43,122). Statistical adjustment for comorbid conditions in addition to age, sex, race, and diabetes explains only a small amount of the lower mortality with home HD. Each year the number of patients with end-stage renal disease (ESRD) in the United States continues to increase. Information from the United States Renal Data System (USDS) shows the prevalence count of treated ESRD has been increasing by 9 to 13% per year and by 1992 there were more than 242,000 prevalent patients [1]. Hemodialysis rather than peritoneal dialysis remains the predominant treatment modality in the United States. Among prevalent dialysis patients in 1992, 81% of patients were being treated with center hemodialysis and only one percent were receiving hemodialysis at home. This was not always the case. Previously a greater proportion of patients were treated with home hemodialysis, but use of this modality has declined progressively over the last 20 years in the United States. This decrease in the proportion of patients treated by home hemodialysis has occurred despite reports of a substantially lower mortality rate with this modality than either center hemodialysis or continuous ambulatory peritoneal dialysis (CAPD) [2, 3]. Also,

Research paper thumbnail of The dose of hemodialysis and patient mortality

Kidney International, 1996

The dose of hemodialysis and patient mortality. The relationship between the delivered dose of he... more The dose of hemodialysis and patient mortality. The relationship between the delivered dose of hemodialysis and patient mortality remains somewhat controversial. Several observational studies have shown improved patient survival with higher levels of delivered dialysis dose. the Kt/V where K is the total (dialyzer plus residual renal

Research paper thumbnail of Clinical and biochemical correlates of starting “daily” hemodialysis

Kidney International, 1999

Hemodialysis patients dialyze intermittently and, alysis. therefore, experience repetitive cyclin... more Hemodialysis patients dialyze intermittently and, alysis. therefore, experience repetitive cycling of body water Background. Daily hemodialysis has been proposed to imcontent, serum osmolality, and dialyzable body constitprove outcomes for patients with end-stage renal disease. There uents. Such cycling is an abnormal physiologic state and has been increasing evidence that daily hemodialysis might may contribute to morbidity and mortality among hemohave potential advantages over intermittent dialysis. However, despite these potential advantages, daily hemodialysis is infre-dialysis patients [1]. It has been proposed that uremia quently used in the United States, and published accounts on should be treated by frequent dialysis to reduce the magthe technique are few. nitude of such swings in body composition [1, 2]. Despite Methods. We describe patient outcomes after increasing the potential advantages of daily hemodialysis, currently, their hemodialysis frequency from three to six times per week hemodialysis for end-stage renal disease (ESRD) is usuin a cohort of 72 patients treated at nine centers during 1972 ally performed three times per week. Data from the to 1996. Analyses of predialysis blood pressure and laboratory parameters from 6 months before until 12 months after starting United States Renal Data System show that in 1993, frequent hemodialysis used a repeated-measures statistical only 0.3% of prevalent hemodialysis patients dialyzed technique. more than three times per week [3]. Results. Predialysis systolic and diastolic blood pressures fell There may be other advantages to daily hemodialysis. by 7 and 4 mm Hg, respectively, after starting frequent hemodi-There is increasing evidence of the beneficial effects of alysis (P ϭ 0.02). Reductions were greatest among patients greater delivered doses of dialysis on patient morbidity being treated with antihypertensive medications, despite a reduction in their dosage of medications. Postdialysis weight fell and mortality [4, 5]. Hemodialysis is most efficient at by 1.0% within one month of starting frequent hemodialysis removing solute early in the course of an individual treatand improved control of hypertension. After the initial drop, ment, and frequent, short hemodialysis sessions can postdialysis weight increased at a rate of 0.85 kg per six months. achieve greater urea removal when the total treatment Serum albumin rose by 0.29 g/dl (P Ͻ 0.001) between months time per week is constant [6, 7]. 1 to 12 of treatment with daily hemodialysis. Hematocrit rose Despite an increasing interest in daily hemodialysis, by 3.0 percentage points (P ϭ 0.02) among patients (N ϭ 56) not treated with erythropoietin during this period. Two years because of recognition of potential benefits of this techafter the start of daily hemodialysis, Kaplan-Meier analyses nique, published accounts of experience with the techshowed a patient survival of 93%, a technique survival of 77%, nique are few and describe limited experience [2, 8-11]. and an arteriovenous fistula patency of 92%. Vascular access To describe the accumulated experience, we report on patency was excellent despite more frequent use of the access. new analyses of data collected from centers known to Conclusions. These results suggest that in certain patients, have treated patients with daily hemodialysis for over daily hemodialysis might have advantages over three times per week hemodialysis. one year. Throughout this article the use of frequent hemodialysis is referred to as daily hemodialysis. In fact, the median frequency of dialysis in the 72 patients de

Research paper thumbnail of Organ donation in the United States

American Journal of Transplantation, 2003

Research paper thumbnail of Haemodialysis prescription, adherence and nutritional indicators in five European countries: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Nephrology Dialysis Transplantation, 2004

Background. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observati... more Background. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study designed to evaluate practice patterns in random samples of haemodialysis facilities and patients across three continents. Participating countries include France, Germany, Italy, Spain and the UK (Euro-DOPPS), Japan and the USA. DOPPS data collection has used the same questionnaires and protocols across all participating countries to assess components of dialysis therapy and outcomes. This study focuses on dialysis prescription, adherence and nutrition among the Euro-DOPPS countries. Methods. In each Euro-DOPPS country, patients were selected randomly from 20-21 representative facilities. Simple means and frequencies were calculated to compare relevant data elements to gain insights into differences in therapeutic aspects among nationally representative patients. Participants entering the study within 90 days of beginning dialysis therapy were excluded from these analyses. Results. Among the five countries, mean delivered dose as measured by normalized urea clearance (Kt/V) varied from 1.28 to 1.50 and was accompanied by differences in dialysis prescription components, including blood flow rates, treatment times, and dialyser membrane and flux characteristics. By country, a nearly 2-fold difference was observed in indicators of patient adherence and management (skipping and shortening dialysis, hyperkalaemia, hyperphosphataemia and high interdialytic weight gain). Indicators of malnutrition varied substantially. Conclusions. This study demonstrates differences in the management of haemodialysis patients across Euro-DOPPS and offers opportunities for improving dialysis dose, adherence and nutrition. Correlation of differences in practice patterns at the dialysis unit level with patient outcomes will offer new insights into improving dialysis therapy.

Research paper thumbnail of ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the United States

Kidney International, 1996

ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the Uni... more ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the United States. The present study evaluated end-stage renal disease (ESRD) patient survival in Lombardy, Italy, and the United States (U.S.) using data from two registries, the Lombardy Dialysis and Transplant Registry (RLDT) and the U.S. Renal Data System (USRDS), respectively. For this purpose, 4,196 white patients (2,900 from the USRDS Case Mix Severity Study and all 1296 from RLDT) who started renal replacement therapy in 1986 and 1987 were studied. Compared to Lombardy patients, those in the USA were significantly older (mean age 59.9 16.4 vs. 55.9 14.7 years), had a lower proportion of males (53.7 vs. 62.1%), a greater proportion with diabetic nephropathy (29.9 vs. 9.7%) and a significantly greater proportion of patients with the recorded comorbid conditions (heart disease, peripheral vascular disease, cirrhosis, cachexia, malignancy). U.S. patients were less frequently treated with peritoneal dialysis (PD) by day 30 of ESRD (21.2 vs. 30.7). Survival was compared in the Cox proportional hazard regression model, using age, sex, comorbid conditions and early modality of treatment as explanatory covariates. Overall, 48% of the 4196 patients died during the 48 to 72 months follow-up to 12/31/91. Per 100 patient-years the gross death rate for USRDS patients was 28.7 compared to 13.0 of RLDT patients. The unadjusted death relative risk for RLDT was 0.439, that is, 56% lower death rate compared to USRDS patients. Age, sex, diabetic status, each of the recorded comorbid conditions and treatment modality were significantly related to survival and included in the model. The Cox cumulative survival adjusted for all these explanatory covariates survival was for U.S. patients 84.4% at one year, 67.0% at two years and 33.4% at five years, and for RLDT patients 88.3% at one year, 75.9% at two years and 45.9% at five years. The relative mortality risk (RR) for the patients treated in Lombardy adjusted for all the reported covariates was 29% lower than for US patients (RR = 0.71; P < 0.0001). This comparative risk varied significantly by age (P < 0.0001) and was 65 percent lower for Lombardy compared to U.S. patients in the age range 25 to 44 years (RR = 0.35) and about 20% lower for patients over age 65 years (RR = 0.80). This relative risk was mainly related to hemodialysis and was not statistically significant for PD patients. The observed lower mortality risk in Lombardy was less pronounced when adjusted for demographic and comorbid covariates, but was still large and therefore suggests the need for further studies regarding treatment related factors and unmeasured patient factors, particularly in hemodialysis patients. The survival of end-stage renal disease (ESRD) in the U.S. patients has been reported to be lower than that of Japan and the

Research paper thumbnail of Nonadherence in hemodialysis: Associations with mortality, hospitalization, and practice patterns in the DOPPS

Kidney International, 2003

Nonadherence in hemodialysis: Associations with mortality, Hemodialysis is a lifesaving but compl... more Nonadherence in hemodialysis: Associations with mortality, Hemodialysis is a lifesaving but complex therapy. It hospitalization, and practice patterns in the DOPPS. makes enormous demands on patients with end-stage Background. Nonadherence among hemodialysis patients renal disease (ESRD), thereby affecting their quality of compromises dialysis delivery, which could influence patient life [1]. Adherence to complicated treatment regimens morbidity and mortality. The Dialysis Outcomes and Practice associated with hemodialysis is vital. The definition of Patterns Study (DOPPS) provides a unique opportunity to review this problem and its determinants on a global level. nonadherence and its assessment have both proven con-Methods. Nonadherence was studied using data from the troversial [2, 3]. However, by compromising the delivery DOPPS, an international, observational, prospective hemoof dialysis, nonadherence can affect both patient morbiddialysis study. Patients were considered nonadherent if they ity and mortality, a finding that is well recognized [4]. skipped one or more sessions per month, shortened one or It has been known for some time that survival of more sessions by more than 10 minutes per month, had a serum potassium level of Ͼ6.0 mEq/L, a serum phosphate level of ESRD patients is better in Europe and Japan in compari-Ͼ7.5 mg/dL (Ͼ2.4 mmol/L), or interdialytic weight gain (IDWG) son with the United States after adjustments for age, Ͼ5.7% of body weight. Predictors of nonadherence were idengender, and diabetes mellitus [5]. Reasons for these diftified using logistic regression. Survival analysis used the Cox ferences are unclear. Differences in practice patterns proportional hazards model adjusting for case-mix. Results. Skipping treatment was associated with increased

Research paper thumbnail of Comparison of Mortality in All Patients on Dialysis, Patients on Dialysis Awaiting Transplantation, and Recipients of a First Cadaveric Transplant

New England Journal of Medicine, 1999

Background The extent to which renal allotransplantation-as compared with long-term dialysisimpro... more Background The extent to which renal allotransplantation-as compared with long-term dialysisimproves survival among patients with end-stage renal disease is controversial, because those selected for transplantation may have a lower base-line risk of death. Methods In an attempt to distinguish the effects of patient selection from those of transplantation itself, we conducted a longitudinal study of mortality in 228,552 patients who were receiving long-term dialysis for end-stage renal disease. Of these patients, 46,164 were placed on a waiting list for transplantation, 23,275 of whom received a first cadaveric transplant between 1991 and 1997. The relative risk of death and survival were assessed with time-dependent nonproportional-hazards analysis, with adjustment for age, race, sex, cause of end-stage renal disease, geographic region, time from first treatment for end-stage renal disease to placement on the waiting list, and year of initial placement on the list.

Research paper thumbnail of Inferior outcome of two-haplotype matched renal transplants in blacks: Role of early rejection

Kidney International, 1995

Inferior outcome of two-haplotype matched (2-HM) renal transplants in blacks: Role of early rejec... more Inferior outcome of two-haplotype matched (2-HM) renal transplants in blacks: Role of early rejection. Acute rejection in the early posttransplant period is a major determinant of long-term outcome. A cohort analysis was performed to evaluate the race-specific incidence rates of early acute rejection episodes (AR) and delayed graft function (DGF) in Americans of African (blacks) and European (whites) descent (N = 2565) who received a 2-HM living-related donor (LRD) first kidney transplant between 1984 and 1992. After adjusting for center and recipient characteristics, blacks had a higher incidence of AR during the initial transplant hospitalization (blacks 13.2% vs. whites 7.4%, OR = 1.64, P = 0.02). DGF also occurred more frequently in blacks (unadjusted OR = 1.58, P = 0.07). Blacks with AR had significantly worse Cox-adjusted five year graft survival than similarly affected whites (blacks 50% vs. whites 76%, P < 0.01). We conclude that failure to take immunosuppressive medications cannot be implicated as a cause of the higher incidence of AR during the initial transplant hospitalization in black kidney transplant recipients. The

Research paper thumbnail of Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates

Kidney International, 1992

Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates. M... more Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates. Mortality tables of the U.S. Renal Data System allow description of national mortality rates among prevalent dialysis patients in five-year age groups and four major categories of causes of ESRD for Black and White patients. Based on these tables derived from over 50,000 deaths in dialysis patients during 1987 to 1989 a methodology is described that allows comparison of local or regional mortality rates to national rates with determination of a standardized mortality ratio and statistical significance. Since this methodology adjusts for patient age, race and cause of ESRD, it can serve as a useful tool for dialysis research and local quality assurance. Outcome studies for patients with end-stage renal disease (ESRD) have focused primarily on mortality rates from the start of ESRD therapy to allow comparisons by diagnosis (such as diabetic vs. non-diabetic), race, gender, age or treatment [1, 2]. With the development of the U.S. Renal Data System (USRDS) [3], validated national U.S. data are available on at least 93% of ESRD patients which allows assessment of national averages of mortality rates for both patient cohorts starting ESRD therapy and for prevalent patients alive at the beginning of a calender year. The latter data serve as a reference for comparison purposes in order to evaluate the mortality observed for a specific group of ESRD patients. This paper describes such reference tables and the method of comparing mortality observed in a specific group of ESRD patients to the mortality that would be expected on the basis of the rates for the U.S. Medicare population of ESRD patients. This method, which expands on rates published in the USRDS Annual Data Report [2], adjusts for patient age, race, and diagnosis. Thus, any differences revealed by this method between the observed and the expected mortality are attributable to factors other than age, race, and diagnosis. This paper also describes the evaluation of the statistical significance of an observed mortality difference. Such adjusted comparisons to the national average could be used to compare the mortality among patients at a specific region or institution to that in the general ESRD population.

Research paper thumbnail of Effect of the dialysis membrane on mortality of chronic hemodialysis patients

Kidney International, 1996

Effect of the dialysis membrane on mortality of chronic hemodialysis patients. Mortality of preva... more Effect of the dialysis membrane on mortality of chronic hemodialysis patients. Mortality of prevalent chronic hemodialysis patients remains high. The potential effect of the dialysis membrane on this mortality has not been previously investigated in a large population of chronic hemodialysis patients. Using data from the United States Renal Data System (USRDS), we analyzed a random sample of 6,536 patients receiving hemodialysis on December 31, 1990. The study design was a historical prospective study. By limiting the study to patients dialyzed for at least one

Research paper thumbnail of Association between vascular access failure and the use of specific drugs: The dialysis outcomes and practice patterns study (DOPPS)

American Journal of Kidney Diseases, 2002

Several drugs have been proposed to improve vascular access patency based on favorable anticoagul... more Several drugs have been proposed to improve vascular access patency based on favorable anticoagulant, antiplatelet, or vascular-remodeling properties. However, there is little evidence to guide drug strategies. The association between vascular access patency and the use of specific drugs was studied in a large sample of US hemodialysis patients enrolled in the Dialysis Outcomes and Practice Patterns Study, an international, prospective, observational study. In general, it was assumed that the drugs were prescribed for indications unrelated to vascular access preservation. Primary (unassisted survival) and secondary vascular access patency (assisted survival) were modeled using Cox regression (time to failure) adjusted for age, sex, race, body mass index, incidence to end-stage renal disease, diabetes mellitus, hypertension, valvular disease, chronic obstructive pulmonary disease, aortic aneurysm, deep-vein thrombosis, number of previous permanent accesses, and facility-clustering effects. Fistulae (n = 900) and grafts (n = 1,944) were evaluated separately. Technical failures within the first 30 days of surgical placement were excluded from the analysis. Treatment with calcium channel blockers was associated with improved primary graft patency (relative risk [RR] for failure, 0.86; P = 0.034). Aspirin therapy was associated with better secondary graft patency (RR, 0.70; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Treatment with angiotensin-converting enzyme inhibitors was associated with significantly better secondary fistula patency (RR, 0.56; P = 0.010). Patients administered warfarin showed worse primary graft patency (RR, 1.33; P = 0.037). These findings should help guide clinical trial priorities toward vascular access preservation using one or more of the agents that show significant risk reduction for access failure in this study.

Research paper thumbnail of Longitudinal assessment of mortality risk among candidates for liver transplantation

Liver Transplantation, 2003

Liver allocation policy recently was modified to use the Model for End-Stage Liver Disease (MELD)... more Liver allocation policy recently was modified to use the Model for End-Stage Liver Disease (MELD) for patients with chronic liver disease to stratify potential recipients according to risk for waitlist death. In this study, a retrospective cohort of 760 adult patients with chronic liver disease placed on the liver transplant waitlist between January 1995 and March 2001 and followed up for up to 74 months was studied to assess the ability of the MELD to predict mortality among waitlisted candidates and evaluate the prognostic importance of changes in MELD score over time. Serial MELD scores predicted waitlist mortality significantly better than baseline MELD scores or medical urgency status. Each unit of the 40-point MELD score was associated with a 22% increased risk for waitlist death (P C .001), whereas medical urgency status was not a significant independent predictor. For any given MELD score, the magnitude and direction of change in MELD score during the previous 30 days (AMELD) was a significant independent mortality predictor. Patients with MELD score increases greater than 5 points over 30 days had a threefold greater waitlist mortality risk than those for whom MELD scores increased more gradually (P < .0001). We conclude that mortality risk on the liver transplant waitlist is predicted more accurately by serial MELD score determinations than by medical urgency status or single MELD measurements. AMELD score over time reflects progression of liver disease and conveys important additional prognostic information that should be considered in the further evolution of national liver allocation policy. (Liver TranspZ2003;9:12-18.)

Research paper thumbnail of Evaluation of the ESRD managed care demonstration operations

Health care financing review, 2003

Individuals with end stage renal disease (ESRD), most of whom are insured by Medicare, are genera... more Individuals with end stage renal disease (ESRD), most of whom are insured by Medicare, are generally prohibited from enrolling in Medicare managed care plans (MCPs). CMS offered ESRD patients the opportunity to participate in an ESRD managed care demonstration mandated by Congress. The demonstration tested whether managed care systems would be of interest to ESRD patients and whether these approaches would be operationally feasible and efficient for treating ESRD patients. This article examines the structure, implementation, and operational outcomes of the three demonstration sites, focusing on: the structure of these managed care programs for ESRD patients, requirements needed to attract and enroll patients, and the challenges of introducing managed care programs in the ESRD arena.

Research paper thumbnail of ESRD managed care demonstration: financial implications

Health care financing review, 2003

In 1996, CMS launched the end stage renal disease (ESRD) managed care demonstration to study the ... more In 1996, CMS launched the end stage renal disease (ESRD) managed care demonstration to study the experience of offering managed care to ESRD patients. This article analyzes the financial impact of the demonstration, which sought to assess its economic impact on the Federal Government, the sites, and the ESRD Medicare beneficiaries. Medicare's costs for demonstration enrollees were greater than they would have been if these enrollees had remained in the fee-for-service (FFS) system. This loss was driven by the lower than average predicted Medicare spending given the demonstration patients' conditions. The sites experienced losses or only modest gains, primarily because they provided a larger benefit package than traditional Medicare coverage, including no patient obligations and other benefits, especially prescription drugs. Patient financial benefits were approximately $9,000 annually.

Research paper thumbnail of Trends in Cost Attributable to Kidney Transplantation Evaluation and Waiting List Management in the United States, 2012-2017

JAMA Network Open

IMPORTANCE While recent policy reforms aim to improve access to kidney transplantation for patien... more IMPORTANCE While recent policy reforms aim to improve access to kidney transplantation for patients with end-stage kidney disease, the cost implications of kidney waiting list expansion are not well understood. The Organ Acquisition Cost Center (OACC) is the mechanism by which Medicare reimburses kidney transplantation programs, at cost, for costs attributable to kidney transplantation evaluation and waiting list management, but these costs have not been well described to date. OBJECTIVES To describe temporal trends in mean OACC costs per kidney transplantation and to identify factors most associated with cost. DESIGN, SETTING, AND PARTICIPANTS This economic evaluation included all kidney transplantation waiting list candidates and recipients in the United States from 2012 to 2017. A population-based study of cost center reports was conducted using data from all Center of Medicare & Medicaid-certified transplantation hospitals. Data analysis was conducted from June to August 2021. EXPOSURES Year, local price index, transplantation and waiting list volume of transplantation program, and comorbidity burden. MAIN OUTCOMES AND MEASURES Mean OACC costs per kidney transplantation.

Research paper thumbnail of The Terrible Toll of the Kidney Shortage

Journal of the American Society of Nephrology, 2018

Research paper thumbnail of Quality of life and patient satisfaction: ESRD managed care demonstration

Health care financing review, 2003

To study the effects of managed care on dialysis patients, we compared the quality of life and pa... more To study the effects of managed care on dialysis patients, we compared the quality of life and patient satisfaction of patients in a managed care demonstration with three comparison samples: fee-for-service (FFS) patients, managed care patients outside the demonstration, and patients in a separate national study. Managed care patients were less satisfied than FFS patients about access to health care providers, but more satisfied with the financial benefits (copayment coverage, prescription drugs, and nutritional supplements) provided under the demonstration managed care plan (MCP). After 1 year in the demonstration, patients exhibited statistically and clinically significant increases in quality of life scores.

Research paper thumbnail of Chronic Renal Failure after Transplantation of a Nonrenal Organ

New England Journal of Medicine, 2003

Transplantation of nonrenal organs is often complicated by chronic renal disease with multifactor... more Transplantation of nonrenal organs is often complicated by chronic renal disease with multifactorial causes. We conducted a population-based cohort analysis to evaluate the incidence of chronic renal failure, risk factors for it, and the associated hazard of death in recipients of nonrenal transplants. methods Pretransplantation and post-transplantation clinical variables and data from a registry of patients with end-stage renal disease (ESRD) were linked in order to estimate the cumulative incidence of chronic renal failure (defined as a glomerular filtration rate of 29 ml per minute per 1.73 m 2 of body-surface area or less or the development of ESRD) and the associated risk of death among 69,321 persons who received nonrenal transplants in the United States between 1990 and 2000. results During a median follow-up of 36 months, chronic renal failure developed in 11,426 patients (16.5 percent). Of these patients, 3297 (28.9 percent) required maintenance dialysis or renal transplantation. The five-year risk of chronic renal failure varied according to the type of organ transplanted-from 6.9 percent among recipients of heart-lung transplants to 21.3 percent among recipients of intestine transplants. Multivariate analysis indicated that an increased risk of chronic renal failure was associated with increasing age (relative risk per 10-year increment, 1.36; P<0.001), female sex (relative risk among male patients as compared with female patients, 0.74; P<0.001), pretransplantation hepatitis C infection (relative risk, 1.15; P<0.001), hypertension (relative risk, 1.18; P<0.001), diabetes mellitus (relative risk, 1.42; P<0.001), and postoperative acute renal failure (relative risk, 2.13; P<0.001). The occurrence of chronic renal failure significantly increased the risk of death (relative risk, 4.55; P<0.001). Treatment of ESRD with kidney transplantation was associated with a five-year risk of death that was significantly lower than that associated with dialysis (relative risk, 0.56; P=0.02). conclusions The five-year risk of chronic renal failure after transplantation of a nonrenal organ ranges from 7 to 21 percent, depending on the type of organ transplanted. The occurrence of chronic renal failure among patients with a nonrenal transplant is associated with an increase by a factor of more than four in the risk of death.

Research paper thumbnail of Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization rates to national rates

Kidney International, 1996

Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization ra... more Using USRDS generated hospitalization tables to compare local dialysis patient hospitalization rates to national rates. Hospitalization tables of the U.S. Renal Data System allow description of national hospitalization rates among incident and prevalent dialysis patients in five-year age groups. These rates are further stratified by sex, race, and four primary disease categories. Based on these tables derived from the data on over 250,000 incident and prevalent patients during 1991 to 1993, a methodology is described that allows comparison of local (for example, dialysis facility) or regional "first admission" rates among incident and prevalent dialysis patients to the national rates. A standardized hospitalization ratio is introduced to facilitate such comparisons, and methods for assessing statistical significance are discussed. Since this methodology allows adjustment for age, race, sex, and primary disease, it can serve as useful tool for dialysis research. It can also be used at the dialysis facility level, alone or in conjunction with the standardized mortality ratio, to facilitate local quality assurance. The U.S. Renal Data System (USRDS) maintains a vast database of information on the end-stage renal disease (ESRD) population of the United States. The primary source of USRDS data is the Health Care Financing Administration (HCFA), and consists primarily of information on patients who are in the Medicare system. It is estimated that the data encompass 93% of all ESRD patients. The data are updated and summarized yearly in the reference tables of the USRDS Annual Data Report. The wealth of information available from the USRDS can be put to use in a variety of valuable ways. The intent of this article is to show how information on patient hospitalization can be used in a simple way to construct a standardized hospitalization ratio (SHR). The SHR is derived in a similar manner to the standardized mortality ratio (SMR) proposed in Wolfe et al [1], and should prove valuable to dialysis facilities interested in comparing their local hospitalization experience to the national norm. Wolfe et a! [1] describe a methodology for comparing the observed mortality rate in a specific group of ESRD patients to national average rates, adjusted for age, race, and primary cause of ESRD. The national rates are calculated based on the reference tables found in the 1990 USRDSAnnua1 Data Report [2]. The

Research paper thumbnail of Comparison of mortality with home hemodialysis and center hemodialysis: A national study

Kidney International, 1996

Comparison of mortality with home hemodialysis and center hemodialysis: A national study. We soug... more Comparison of mortality with home hemodialysis and center hemodialysis: A national study. We sought to determine whether lower mortality rates reported with hemodialysis (HD) at home compared to hemodialysis in dialysis centers (center HD) could be explained by patient selection. Data are from the United States Renal Data System (USRDS) Special Study Of Case Mix Severity, a random national sample of 4,892 patients who started renal replacement therapy in 1986 to 1987. Intent-to-treat analyses compared mortality between home HD (N = 70) and center HD patients (N = 3,102) using the Cox proportional hazards model. Home HD patients were younger and had a lower frequency of comorbid conditions. The unadjusted relative risk (RR) of death for home HD patients compared to center HD was 0.37 (P < 0.001). The RR adjusted for age, sex, race and diabetes, was 44% lower in home HD patients (RR = 0.56, P = 0.02). When additionally adjusted for comorbid conditions, this RR increased marginally (RR = 0.58, P = 0.03). A different analysis using national USRDS data from 1986/7 and without comorbid adjustment showed patients with training for self care hemodialysis at home or in a center (N = 418) had a lower mortality risk (RR = 0.78, P = 0.001) than center HD patients (N = 43,122). Statistical adjustment for comorbid conditions in addition to age, sex, race, and diabetes explains only a small amount of the lower mortality with home HD. Each year the number of patients with end-stage renal disease (ESRD) in the United States continues to increase. Information from the United States Renal Data System (USDS) shows the prevalence count of treated ESRD has been increasing by 9 to 13% per year and by 1992 there were more than 242,000 prevalent patients [1]. Hemodialysis rather than peritoneal dialysis remains the predominant treatment modality in the United States. Among prevalent dialysis patients in 1992, 81% of patients were being treated with center hemodialysis and only one percent were receiving hemodialysis at home. This was not always the case. Previously a greater proportion of patients were treated with home hemodialysis, but use of this modality has declined progressively over the last 20 years in the United States. This decrease in the proportion of patients treated by home hemodialysis has occurred despite reports of a substantially lower mortality rate with this modality than either center hemodialysis or continuous ambulatory peritoneal dialysis (CAPD) [2, 3]. Also,

Research paper thumbnail of The dose of hemodialysis and patient mortality

Kidney International, 1996

The dose of hemodialysis and patient mortality. The relationship between the delivered dose of he... more The dose of hemodialysis and patient mortality. The relationship between the delivered dose of hemodialysis and patient mortality remains somewhat controversial. Several observational studies have shown improved patient survival with higher levels of delivered dialysis dose. the Kt/V where K is the total (dialyzer plus residual renal

Research paper thumbnail of Clinical and biochemical correlates of starting “daily” hemodialysis

Kidney International, 1999

Hemodialysis patients dialyze intermittently and, alysis. therefore, experience repetitive cyclin... more Hemodialysis patients dialyze intermittently and, alysis. therefore, experience repetitive cycling of body water Background. Daily hemodialysis has been proposed to imcontent, serum osmolality, and dialyzable body constitprove outcomes for patients with end-stage renal disease. There uents. Such cycling is an abnormal physiologic state and has been increasing evidence that daily hemodialysis might may contribute to morbidity and mortality among hemohave potential advantages over intermittent dialysis. However, despite these potential advantages, daily hemodialysis is infre-dialysis patients [1]. It has been proposed that uremia quently used in the United States, and published accounts on should be treated by frequent dialysis to reduce the magthe technique are few. nitude of such swings in body composition [1, 2]. Despite Methods. We describe patient outcomes after increasing the potential advantages of daily hemodialysis, currently, their hemodialysis frequency from three to six times per week hemodialysis for end-stage renal disease (ESRD) is usuin a cohort of 72 patients treated at nine centers during 1972 ally performed three times per week. Data from the to 1996. Analyses of predialysis blood pressure and laboratory parameters from 6 months before until 12 months after starting United States Renal Data System show that in 1993, frequent hemodialysis used a repeated-measures statistical only 0.3% of prevalent hemodialysis patients dialyzed technique. more than three times per week [3]. Results. Predialysis systolic and diastolic blood pressures fell There may be other advantages to daily hemodialysis. by 7 and 4 mm Hg, respectively, after starting frequent hemodi-There is increasing evidence of the beneficial effects of alysis (P ϭ 0.02). Reductions were greatest among patients greater delivered doses of dialysis on patient morbidity being treated with antihypertensive medications, despite a reduction in their dosage of medications. Postdialysis weight fell and mortality [4, 5]. Hemodialysis is most efficient at by 1.0% within one month of starting frequent hemodialysis removing solute early in the course of an individual treatand improved control of hypertension. After the initial drop, ment, and frequent, short hemodialysis sessions can postdialysis weight increased at a rate of 0.85 kg per six months. achieve greater urea removal when the total treatment Serum albumin rose by 0.29 g/dl (P Ͻ 0.001) between months time per week is constant [6, 7]. 1 to 12 of treatment with daily hemodialysis. Hematocrit rose Despite an increasing interest in daily hemodialysis, by 3.0 percentage points (P ϭ 0.02) among patients (N ϭ 56) not treated with erythropoietin during this period. Two years because of recognition of potential benefits of this techafter the start of daily hemodialysis, Kaplan-Meier analyses nique, published accounts of experience with the techshowed a patient survival of 93%, a technique survival of 77%, nique are few and describe limited experience [2, 8-11]. and an arteriovenous fistula patency of 92%. Vascular access To describe the accumulated experience, we report on patency was excellent despite more frequent use of the access. new analyses of data collected from centers known to Conclusions. These results suggest that in certain patients, have treated patients with daily hemodialysis for over daily hemodialysis might have advantages over three times per week hemodialysis. one year. Throughout this article the use of frequent hemodialysis is referred to as daily hemodialysis. In fact, the median frequency of dialysis in the 72 patients de

Research paper thumbnail of Organ donation in the United States

American Journal of Transplantation, 2003

Research paper thumbnail of Haemodialysis prescription, adherence and nutritional indicators in five European countries: results from the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Nephrology Dialysis Transplantation, 2004

Background. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observati... more Background. The Dialysis Outcomes and Practice Patterns Study (DOPPS) is a prospective, observational study designed to evaluate practice patterns in random samples of haemodialysis facilities and patients across three continents. Participating countries include France, Germany, Italy, Spain and the UK (Euro-DOPPS), Japan and the USA. DOPPS data collection has used the same questionnaires and protocols across all participating countries to assess components of dialysis therapy and outcomes. This study focuses on dialysis prescription, adherence and nutrition among the Euro-DOPPS countries. Methods. In each Euro-DOPPS country, patients were selected randomly from 20-21 representative facilities. Simple means and frequencies were calculated to compare relevant data elements to gain insights into differences in therapeutic aspects among nationally representative patients. Participants entering the study within 90 days of beginning dialysis therapy were excluded from these analyses. Results. Among the five countries, mean delivered dose as measured by normalized urea clearance (Kt/V) varied from 1.28 to 1.50 and was accompanied by differences in dialysis prescription components, including blood flow rates, treatment times, and dialyser membrane and flux characteristics. By country, a nearly 2-fold difference was observed in indicators of patient adherence and management (skipping and shortening dialysis, hyperkalaemia, hyperphosphataemia and high interdialytic weight gain). Indicators of malnutrition varied substantially. Conclusions. This study demonstrates differences in the management of haemodialysis patients across Euro-DOPPS and offers opportunities for improving dialysis dose, adherence and nutrition. Correlation of differences in practice patterns at the dialysis unit level with patient outcomes will offer new insights into improving dialysis therapy.

Research paper thumbnail of ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the United States

Kidney International, 1996

ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the Uni... more ESRD patient mortality with adjustment for comorbid conditions in Lombardy (Italy) versus the United States. The present study evaluated end-stage renal disease (ESRD) patient survival in Lombardy, Italy, and the United States (U.S.) using data from two registries, the Lombardy Dialysis and Transplant Registry (RLDT) and the U.S. Renal Data System (USRDS), respectively. For this purpose, 4,196 white patients (2,900 from the USRDS Case Mix Severity Study and all 1296 from RLDT) who started renal replacement therapy in 1986 and 1987 were studied. Compared to Lombardy patients, those in the USA were significantly older (mean age 59.9 16.4 vs. 55.9 14.7 years), had a lower proportion of males (53.7 vs. 62.1%), a greater proportion with diabetic nephropathy (29.9 vs. 9.7%) and a significantly greater proportion of patients with the recorded comorbid conditions (heart disease, peripheral vascular disease, cirrhosis, cachexia, malignancy). U.S. patients were less frequently treated with peritoneal dialysis (PD) by day 30 of ESRD (21.2 vs. 30.7). Survival was compared in the Cox proportional hazard regression model, using age, sex, comorbid conditions and early modality of treatment as explanatory covariates. Overall, 48% of the 4196 patients died during the 48 to 72 months follow-up to 12/31/91. Per 100 patient-years the gross death rate for USRDS patients was 28.7 compared to 13.0 of RLDT patients. The unadjusted death relative risk for RLDT was 0.439, that is, 56% lower death rate compared to USRDS patients. Age, sex, diabetic status, each of the recorded comorbid conditions and treatment modality were significantly related to survival and included in the model. The Cox cumulative survival adjusted for all these explanatory covariates survival was for U.S. patients 84.4% at one year, 67.0% at two years and 33.4% at five years, and for RLDT patients 88.3% at one year, 75.9% at two years and 45.9% at five years. The relative mortality risk (RR) for the patients treated in Lombardy adjusted for all the reported covariates was 29% lower than for US patients (RR = 0.71; P < 0.0001). This comparative risk varied significantly by age (P < 0.0001) and was 65 percent lower for Lombardy compared to U.S. patients in the age range 25 to 44 years (RR = 0.35) and about 20% lower for patients over age 65 years (RR = 0.80). This relative risk was mainly related to hemodialysis and was not statistically significant for PD patients. The observed lower mortality risk in Lombardy was less pronounced when adjusted for demographic and comorbid covariates, but was still large and therefore suggests the need for further studies regarding treatment related factors and unmeasured patient factors, particularly in hemodialysis patients. The survival of end-stage renal disease (ESRD) in the U.S. patients has been reported to be lower than that of Japan and the

Research paper thumbnail of Nonadherence in hemodialysis: Associations with mortality, hospitalization, and practice patterns in the DOPPS

Kidney International, 2003

Nonadherence in hemodialysis: Associations with mortality, Hemodialysis is a lifesaving but compl... more Nonadherence in hemodialysis: Associations with mortality, Hemodialysis is a lifesaving but complex therapy. It hospitalization, and practice patterns in the DOPPS. makes enormous demands on patients with end-stage Background. Nonadherence among hemodialysis patients renal disease (ESRD), thereby affecting their quality of compromises dialysis delivery, which could influence patient life [1]. Adherence to complicated treatment regimens morbidity and mortality. The Dialysis Outcomes and Practice associated with hemodialysis is vital. The definition of Patterns Study (DOPPS) provides a unique opportunity to review this problem and its determinants on a global level. nonadherence and its assessment have both proven con-Methods. Nonadherence was studied using data from the troversial [2, 3]. However, by compromising the delivery DOPPS, an international, observational, prospective hemoof dialysis, nonadherence can affect both patient morbiddialysis study. Patients were considered nonadherent if they ity and mortality, a finding that is well recognized [4]. skipped one or more sessions per month, shortened one or It has been known for some time that survival of more sessions by more than 10 minutes per month, had a serum potassium level of Ͼ6.0 mEq/L, a serum phosphate level of ESRD patients is better in Europe and Japan in compari-Ͼ7.5 mg/dL (Ͼ2.4 mmol/L), or interdialytic weight gain (IDWG) son with the United States after adjustments for age, Ͼ5.7% of body weight. Predictors of nonadherence were idengender, and diabetes mellitus [5]. Reasons for these diftified using logistic regression. Survival analysis used the Cox ferences are unclear. Differences in practice patterns proportional hazards model adjusting for case-mix. Results. Skipping treatment was associated with increased

Research paper thumbnail of Comparison of Mortality in All Patients on Dialysis, Patients on Dialysis Awaiting Transplantation, and Recipients of a First Cadaveric Transplant

New England Journal of Medicine, 1999

Background The extent to which renal allotransplantation-as compared with long-term dialysisimpro... more Background The extent to which renal allotransplantation-as compared with long-term dialysisimproves survival among patients with end-stage renal disease is controversial, because those selected for transplantation may have a lower base-line risk of death. Methods In an attempt to distinguish the effects of patient selection from those of transplantation itself, we conducted a longitudinal study of mortality in 228,552 patients who were receiving long-term dialysis for end-stage renal disease. Of these patients, 46,164 were placed on a waiting list for transplantation, 23,275 of whom received a first cadaveric transplant between 1991 and 1997. The relative risk of death and survival were assessed with time-dependent nonproportional-hazards analysis, with adjustment for age, race, sex, cause of end-stage renal disease, geographic region, time from first treatment for end-stage renal disease to placement on the waiting list, and year of initial placement on the list.

Research paper thumbnail of Inferior outcome of two-haplotype matched renal transplants in blacks: Role of early rejection

Kidney International, 1995

Inferior outcome of two-haplotype matched (2-HM) renal transplants in blacks: Role of early rejec... more Inferior outcome of two-haplotype matched (2-HM) renal transplants in blacks: Role of early rejection. Acute rejection in the early posttransplant period is a major determinant of long-term outcome. A cohort analysis was performed to evaluate the race-specific incidence rates of early acute rejection episodes (AR) and delayed graft function (DGF) in Americans of African (blacks) and European (whites) descent (N = 2565) who received a 2-HM living-related donor (LRD) first kidney transplant between 1984 and 1992. After adjusting for center and recipient characteristics, blacks had a higher incidence of AR during the initial transplant hospitalization (blacks 13.2% vs. whites 7.4%, OR = 1.64, P = 0.02). DGF also occurred more frequently in blacks (unadjusted OR = 1.58, P = 0.07). Blacks with AR had significantly worse Cox-adjusted five year graft survival than similarly affected whites (blacks 50% vs. whites 76%, P < 0.01). We conclude that failure to take immunosuppressive medications cannot be implicated as a cause of the higher incidence of AR during the initial transplant hospitalization in black kidney transplant recipients. The

Research paper thumbnail of Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates

Kidney International, 1992

Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates. M... more Using USRDS generated mortality tables to compare local ESRD mortality rates to national rates. Mortality tables of the U.S. Renal Data System allow description of national mortality rates among prevalent dialysis patients in five-year age groups and four major categories of causes of ESRD for Black and White patients. Based on these tables derived from over 50,000 deaths in dialysis patients during 1987 to 1989 a methodology is described that allows comparison of local or regional mortality rates to national rates with determination of a standardized mortality ratio and statistical significance. Since this methodology adjusts for patient age, race and cause of ESRD, it can serve as a useful tool for dialysis research and local quality assurance. Outcome studies for patients with end-stage renal disease (ESRD) have focused primarily on mortality rates from the start of ESRD therapy to allow comparisons by diagnosis (such as diabetic vs. non-diabetic), race, gender, age or treatment [1, 2]. With the development of the U.S. Renal Data System (USRDS) [3], validated national U.S. data are available on at least 93% of ESRD patients which allows assessment of national averages of mortality rates for both patient cohorts starting ESRD therapy and for prevalent patients alive at the beginning of a calender year. The latter data serve as a reference for comparison purposes in order to evaluate the mortality observed for a specific group of ESRD patients. This paper describes such reference tables and the method of comparing mortality observed in a specific group of ESRD patients to the mortality that would be expected on the basis of the rates for the U.S. Medicare population of ESRD patients. This method, which expands on rates published in the USRDS Annual Data Report [2], adjusts for patient age, race, and diagnosis. Thus, any differences revealed by this method between the observed and the expected mortality are attributable to factors other than age, race, and diagnosis. This paper also describes the evaluation of the statistical significance of an observed mortality difference. Such adjusted comparisons to the national average could be used to compare the mortality among patients at a specific region or institution to that in the general ESRD population.

Research paper thumbnail of Effect of the dialysis membrane on mortality of chronic hemodialysis patients

Kidney International, 1996

Effect of the dialysis membrane on mortality of chronic hemodialysis patients. Mortality of preva... more Effect of the dialysis membrane on mortality of chronic hemodialysis patients. Mortality of prevalent chronic hemodialysis patients remains high. The potential effect of the dialysis membrane on this mortality has not been previously investigated in a large population of chronic hemodialysis patients. Using data from the United States Renal Data System (USRDS), we analyzed a random sample of 6,536 patients receiving hemodialysis on December 31, 1990. The study design was a historical prospective study. By limiting the study to patients dialyzed for at least one

Research paper thumbnail of Association between vascular access failure and the use of specific drugs: The dialysis outcomes and practice patterns study (DOPPS)

American Journal of Kidney Diseases, 2002

Several drugs have been proposed to improve vascular access patency based on favorable anticoagul... more Several drugs have been proposed to improve vascular access patency based on favorable anticoagulant, antiplatelet, or vascular-remodeling properties. However, there is little evidence to guide drug strategies. The association between vascular access patency and the use of specific drugs was studied in a large sample of US hemodialysis patients enrolled in the Dialysis Outcomes and Practice Patterns Study, an international, prospective, observational study. In general, it was assumed that the drugs were prescribed for indications unrelated to vascular access preservation. Primary (unassisted survival) and secondary vascular access patency (assisted survival) were modeled using Cox regression (time to failure) adjusted for age, sex, race, body mass index, incidence to end-stage renal disease, diabetes mellitus, hypertension, valvular disease, chronic obstructive pulmonary disease, aortic aneurysm, deep-vein thrombosis, number of previous permanent accesses, and facility-clustering effects. Fistulae (n = 900) and grafts (n = 1,944) were evaluated separately. Technical failures within the first 30 days of surgical placement were excluded from the analysis. Treatment with calcium channel blockers was associated with improved primary graft patency (relative risk [RR] for failure, 0.86; P = 0.034). Aspirin therapy was associated with better secondary graft patency (RR, 0.70; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Treatment with angiotensin-converting enzyme inhibitors was associated with significantly better secondary fistula patency (RR, 0.56; P = 0.010). Patients administered warfarin showed worse primary graft patency (RR, 1.33; P = 0.037). These findings should help guide clinical trial priorities toward vascular access preservation using one or more of the agents that show significant risk reduction for access failure in this study.