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Background Since the bundled end-stage renal disease prospective payment system began in 2011 in the United States, some hemodialysis practices have changed substantially, raising the question of whether vascular access practice also has changed. We describe monthly US vascular access use from August 2010 to August 2013 with international comparisons, and other aspects of US vascular access practice. Study Design Prospective observational cohort study of vascular access. Setting & Participants Maintenance hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS) Practice Monitor (DPM) in the United States (N=3,442; US patients) and 19 other nations (N=8,478). Predictors Country, patient demographics, time period. Outcomes Vascular access use, pre–end-stage renal disease access timing of first nephrologist care and arteriovenous access placement, patient self-reported vascular access preferences (United States only), treatment practices as stated by medical directors. Results In the United States from August 2010 to August 2013, arteriovenous fistula (AVF) use increased from 63% to 68%, while catheter use declined from 19% to 15%. Although AVF use did not differ greatly across age groups, arteriovenous graft use was 2-fold higher among black (26%) versus nonblack US patients (13%) in 2013. Across 20 countries in 2013, AVF use ranged from 49% to 92%, whereas catheter use ranged from 1% to 45%. Patient-reported vascular access preferences differed by sex and race, with 16% to 20% of patients feeling uninformed regarding benefits/risks of different vascular access types. Among new (incident) US hemodialysis patients, AVF use remains low, with ∼70% initiating hemodialysis therapy with a catheter (60% starting with catheter when having ≥4 months of predialysis nephrology care). In the United States, longer typical times to first AVF cannulation were reported. Limitations Noncompletion of surveys may affect the generalizability of findings to the wider hemodialysis population. Conclusions AVF use has increased, with catheter use decreasing among prevalent US hemodialysis patients since the introduction of the prospective payment system. However, AVF use at dialysis therapy initiation remains low, suggesting that reforms affecting predialysis care may be necessary to incentivize improvements in fistula rates at dialysis therapy initiation as achieved for prevalent hemodialysis patients.

When randomized controlled trials are unavailable, clinicians have to rely on observational studies. However, analyses using observational data to evaluate specific treatments and their associations with outcomes often are biased through confounding by clinical indication for the treatment of interest. Given the rich observational data and limited clinical trial data available in the dialysis population, successfully accounting for this bias can lead to substantial knowledge generation. In recent decades, much has been learned about statistical methods for observational data, including the fact that even extensive adjustments may not always overcome this bias, particularly when unmeasured confounders exist. In this article, examples based on the international DOPPS (Dialysis Outcomes and Practice Patterns Study) are used to demonstrate the value of practice-based instrumental variable analyses. This methodology leverages the marked differences in practice patterns among dialysis facilities and uses the reasonable assumption that patients are assigned to a dialysis facility without consideration of its specific treatment pattern in order to minimize bias in analyses relying on observational data. Examples using the dialysis facility as an instrument that are reviewed in depth in this article include studies of dialysate sodium concentration, systolic blood pressure targets, and treatment time, demonstrate the value of this methodology to produce advanced knowledge. However, practice-based analyses have potential limitations. Specifically, observation of sufficiently large differences in practice patterns is required and these analyses should consider that the treatment of interest may be associated with other facility treatment practices. These examples from the DOPPS hopefully will stimulate advances in methodologies and critical clinical work toward improving patient care by identifying beneficial treatment practices applicable to dialysis, chronic kidney disease, and beyond.

Background Most hemodialysis patients worldwide are treated with bicarbonate dialysis using sodium bicarbonate as the base. Few studies have assessed outcomes of patients treated with different dialysate bicarbonate levels, and the optimal concentration remains uncertain. Study Design The Dialysis Outcomes and Practice Patterns Study (DOPPS) is an international prospective cohort study. Setting & Participants This study included 17,031 patients receiving thrice-weekly in-center hemodialysis from 11 DOPPS countries (2002-2011). Predictor Dialysate bicarbonate concentration. Outcomes All-cause and cause-specific mortality and first hospitalization, using Cox regression to estimate the effects of dialysate bicarbonate concentration, adjusting for potential confounders. Measurements Demographics, comorbid conditions, laboratory values, and prescriptions were abstracted from medical records. Results Mean dialysate bicarbonate concentration was 35.5 ± 2.7 (SD) mEq/L, ranging from 32.2 ± 2.3 mEq/L in Germany to 37.0 ± 2.6 mEq/L in the United States. Prescription of high dialysate bicarbonate concentration (≥38 mEq/L) was most common in the United States (45% of patients). Approximately 50% of DOPPS facilities used a single dialysate bicarbonate concentration. 3,913 patients (23%) died during follow-up. Dialysate bicarbonate concentration was associated positively with mortality (adjusted HR, 1.08 per 4 mEq/L higher [95% CI, 1.01-1.15]; HR for dialysate bicarbonate ≥38 vs 33-37 mEq/L, 1.07 [95% CI, 0.97-1.19]). Results were consistent across levels of pre–dialysis session serum bicarbonate and between facilities that used a single dialysate bicarbonate concentration and those that prescribed different concentrations to individual patients. The association of dialysis bicarbonate concentration with mortality was stronger in patients with longer dialysis vintage. Limitations Due to the observational nature of the present study, we cannot rule out that the reported associations may be biased by unmeasured confounders. Conclusions High dialysate bicarbonate concentrations, especially prolonged exposure, may contribute to adverse outcomes, likely through the development of postdialysis metabolic alkalosis. Additional studies are warranted to identify the optimal dialysate bicarbonate concentration.

Background Sudden death is a leading cause of death in patients on maintenance hemodialysis therapy. During hemodialysis sessions, the gradient between serum and dialysate levels results in rapid electrolyte shifts, which may contribute to arrhythmias and sudden death. Controversies exist about the optimal electrolyte concentration in the dialysate; specifically, it is unclear whether patient outcomes differ among those treated with a dialysate potassium concentration of 3 mEq/L compared to 2 mEq/L. Study Design Prospective cohort study. Setting & Participants 55,183 patients from 20 countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 1 to 5 (1996-2015). Predictor Dialysate potassium concentration at study entry. Outcomes Cox regression was used to estimate the association between dialysate potassium concentration and both all-cause mortality and an arrhythmia composite outcome (arrhythmia-related hospitalization or sudden death), adjusting for potential confounders. Results During a median follow-up of 16.5 months, 24% of patients died and 7% had an arrhythmia composite outcome. No meaningful difference in clinical outcomes was observed for patients treated with a dialysate potassium concentration of 3 versus 2 mEq/L (adjusted HRs were 0.96 [95% CI, 0.91-1.01] for mortality and 0.98 [95% CI, 0.88-1.08] for arrhythmia composite). Results were similar across predialysis serum potassium levels. As in prior studies, higher serum potassium level was associated with adverse outcomes. However, dialysate potassium concentration had only minimal impact on serum potassium level measured predialysis (+0.09 [95% CI, 0.05-0.14] mEq/L serum potassium per 1 mEq/L greater dialysate potassium concentration). Limitations Data were not available for delivered (vs prescribed) dialysate potassium concentration and postdialysis serum potassium level; possible unmeasured confounding. Conclusions In combination, these results suggest that approaches other than altering dialysate potassium concentration (eg, education on dietary potassium sources and prescription of potassium-binding medications) may merit further attention to reduce risks associated with high serum potassium levels.

BackgroundHigh interdialytic weight gain (IDWG) is associated with adverse outcomes in hemodialysis (HD) patients. We identified temporal and regional trends in IDWG, predictors of IDWG, and associations of IDWG with clinical outcomes.Study DesignAnalysis 1: sequential cross-sections to identify facility- and patient-level predictors of IDWG and their temporal trends. Analysis 2: prospective cohort study to assess associations between IDWG and mortality and hospitalization risk.Setting & Participants21,919 participants on HD therapy for 1 year or longer in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 2 to 5 (2002-2014).PredictorsAnalysis 1: study phase, patient demographics and comorbid conditions, HD facility practices. Analysis 2: relative IDWG, expressed as percentage of post-HD weight (

Background Poor nutritional status and both hyper- and hypophosphatemia are associated with increased mortality in maintenance hemodialysis (HD) patients. We assessed associations of phosphate binder prescription with survival and indicators of nutritional status in maintenance HD patients. Study Design Prospective cohort study (DOPPS [Dialysis Outcomes and Practice Patterns Study]), 1996-2008. Setting & Participants 23,898 maintenance HD patients at 923 facilities in 12 countries. Predictors Patient-level phosphate binder prescription and case-mix–adjusted facility percentage of phosphate binder prescription using an instrumental-variable analysis. Outcome All-cause mortality. Results Overall, 88% of patients were prescribed phosphate binders. Distributions of age, comorbid conditions, and other characteristics showed small differences between facilities with higher and lower percentages of phosphate binder prescription. Patient-level phosphate binder prescription was associated strongly at baseline with indicators of better nutrition, ie, higher values for serum creatinine, albumin, normalized protein catabolic rate, and body mass index and absence of cachectic appearance. Overall, patients prescribed phosphate binders had 25% lower mortality (HR, 0.75; 95% CI, 0.68-0.83) when adjusted for serum phosphorus level and other covariates; further adjustment for nutritional indicators attenuated this association (HR, 0.88; 95% CI, 0.80-0.97). However, this inverse association was observed for only patients with serum phosphorus levels ≥3.5 mg/dL. In the instrumental-variable analysis, case-mix–adjusted facility percentage of phosphate binder prescription (range, 23%-100%) was associated positively with better nutritional status and inversely with mortality (HR for 10% more phosphate binders, 0.93; 95% CI, 0.89-0.96). Further adjustment for nutritional indicators reduced this association to an HR of 0.95 (95% CI, 0.92-0.99). Limitations Results were based on phosphate binder prescription; phosphate binder and nutritional data were cross-sectional; dietary restriction was not assessed; observational design limits causal inference due to possible residual confounding. Conclusions Longer survival and better nutritional status were observed for maintenance HD patients prescribed phosphate binders and in facilities with a greater percentage of phosphate binder prescription. Understanding the mechanisms for explaining this effect and ruling out possible residual confounding require additional research.

Predialysis serum sodium concentrations recently have been linked to patient characteristics and outcomes in hemodialysis patients and may have implications for the dialysate sodium prescription.Prospective cohort study.11,555 patients from 12 countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS), phases I (1996-2001) and III (2005-2008).Demographics, comorbid conditions, laboratory measurements (model 1); mean serum sodium level, dialysate sodium concentration (model 2).Serum sodium level, using adjusted linear mixed models (model 1); all-cause mortality, using Cox proportional hazards models (model 2).Median follow-up was 12 months, with 1,727 deaths (15%) occurring during the study period (12,274 patient-years). Mean serum sodium level in the DOPPS countries was 138.5 ± 2.8 mEq/L. Japan had the highest (139.1 ± 2.6 mEq/L) and Australia/New Zealand had the lowest mean serum sodium level (137.4 ± 2.8 mEq/L). Serum sodium level was associated positively with male sex, black race, body mass index, serum albumin level, and creatinine level and negatively with neurologic and psychiatric disease, white blood cell count, and intradialytic weight loss (0.16 mEq/L lower per 1% loss). Higher serum sodium level was associated with lower adjusted all-cause mortality in a continuous model (HR, 0.95 per 1 mEq/L higher; 95% CI, 0.93-0.97). Dialysate sodium prescription was not associated with serum sodium level. Mortality analyses restricted to the serum sodium tertile with the highest mortality (serum sodium137 mEq/L) showed lower mortality risk in patients with dialysate sodium prescriptions140 mEq/L.Causality cannot be established in this observational study, which does not consider potential effects of dialysate sodium level on postdialysis thirst, dietary salt and water intake, interdialytic weight gain, and cardiovascular stability.Lower serum sodium levels are associated with certain hemodialysis patient characteristics and higher adjusted risk of death. The lower mortality observed in our adjusted analyses in patients with serum sodium levels137 mEq/L dialyzed against dialysate sodium prescriptions140 mEq/L is intriguing, may be related to intradialytic cardiovascular stability, and deserves further study.

Background Hemodialysis patients with larger hemoglobin level fluctuations have higher mortality rates. We describe facility-level interpatient hemoglobin variability, its relation to patient mortality, and factors associated with facility-level hemoglobin variability or achieving hemoglobin levels of 10.5-12.0 g/dL. Facility-level hemoglobin variability may reflect within-patient hemoglobin variability and facility-level anemia-control practices. Study Design Prospective cohort study. Setting & Participants Data from the Dialysis Outcomes and Practice Patterns Study (DOPPS; 26,510 hemodialysis patients, 930 facilities, 12 countries, 1996-2008) and from the Centers for Medicare & Medicaid Services (CMS; 193,291 hemodialysis patients, 3,741 US facilities, 2002). Predictors Standard deviation (SD) in single-measurement hemoglobin levels in hemodialysis patients in facility cross-sections (facility-level hemoglobin SD); patient characteristics; facility practices. Outcomes Patient-level mortality; additionally, facility practices correlated with facility-level hemoglobin SD or patient hemoglobin levels of 10.5-12.0 g/dL. Results Facility-level hemoglobin SD varied more than 5-fold across DOPPS facilities (range, 0.5-2.7 g/dL; mean, 1.3 g/dL) and by country (range, 1.1 in Japan-DOPPS [2005/2006] to 1.7 g/dL in Spain-DOPPS [1998/1999]), with substantial decreases seen in many countries from 1998 to 2007. Facility-level hemoglobin SD was related inversely to patient age, but was associated minimally with more than 30 other patient characteristics and facility mean hemoglobin levels. Several anemia management practices were associated strongly with facility-level hemoglobin SD and having a hemoglobin level of 10.5-12.0 g/dL. When examined in CMS data, facility-level hemoglobin SD was positively associated with within-patient hemoglobin SD during the prior 6 months. Patient mortality rates were higher with greater facility-level hemoglobin SD (DOPPS: HR, 1.08 per 0.5-g/dL greater facility-level hemoglobin SD [95% CI, 1.02-1.15; P = 0.006]; CMS: HR, 1.16 per 0.5-g/dL greater facility-level hemoglobin SD [95% CI, 1.11-1.21; P Limitations Residual confounding. Conclusions Facility-level hemoglobin SD was associated strongly and positively with patient mortality, not tightly linked to numerous patient characteristics, but related strongly to facility anemia management practices. Facility-level hemoglobin variability may be modifiable and its optimization may improve hemodialysis patient survival.

Recognizing that autologous arteriovenous fistula use was associated with improved outcomes in hemodialysis patients, the 1997 Dialysis Outcomes Quality Initiative (DOQI) vascular access practice guidelines from the National Kidney Foundation stressed fistulas as the optimal means of dialysis vascular access. In the United States, this emphasis has continued with the Fistula First Breakthrough Initiative. Much of the data supporting fistulas for dialysis access are derived from longitudinal cohorts, including the Dialysis Outcomes and Practice Patterns Study (DOPPS), dialysis provider databases, and other sources. This article reviews major findings from these data sources, focusing on specific practices and characteristics associated with greater arteriovenous fistula use in dialysis facilities worldwide. Important and often overlooked characteristics that are discussed in detail include specific preferences of dialysis staff regarding access type and the emphasis placed on fistula primacy and the number of fistulas created during surgical training. For example, in the DOPPS, the risk of initial fistula failure was 34% lower when fistulas were placed by surgeons who had created at least 25 fistulas during training (P = 0.002). It is imperative that dialysis clinicians advocate actively for specific dialysis access types on behalf of individual patients. Vascular surgery teaching programs must supervise adequate numbers of fistula procedures for every trainee.

A substantial number of patients return to dialysis therapy after a renal transplant fails. It is not clear whether mortality increases among patients with graft failure relative to those on the waiting list who have not yet received a kidney transplant.Data from the Scientific Registry of Transplant Recipients were analyzed (N = 175,436). Cox regression with time-dependent covariates was used to compare mortality between post-graft failure dialysis patients and primary transplant candidates on dialysis therapy. Mortality hazard ratios (HRs) were adjusted for age, sex, race, cause of end-stage renal disease, pre-waiting list time on dialysis therapy, calendar year of wait-listing, and organ procurement organization.Overall, the post-graft failure dialysis group experienced a significant 78% greater mortality (HR, 1.78; P0.0001) relative to the transplant candidate group. The post-graft failure dialysis/transplant candidate HR was relatively constant across age groups, but significantly greater (P0.0001) among patients with diabetes (HR, 1.93) than among those without diabetes (HR, 1.69). The HR was greatest during the first week after graft failure (HR, 13.6; P0.0001) and decreased steadily thereafter. However, despite leveling off, the HR remained significantly elevated well after graft failure, including the 5- to 10-year period after graft failure.Based on national data, mortality among patients on dialysis therapy after primary graft failure increases significantly relative to mortality among patients still awaiting primary kidney transplantation. Additional studies are urgently needed to define the mechanism of the increased risk and strategies to decrease mortality.

Background: Medications affect many measures of hemodialysis patients' well-being. Methods: The Dialysis Outcomes and Practice Patterns Study (DOPPS) has evaluated the use of hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins), analgesics, antidepressants, and multivitamins. Additionally, DOPPS has reported on the associations between vascular access outcomes and related medications. Results: Prescription of statins varied widely across countries, with the highest use in the United States. Patients prescribed statins had lower risk of cardiac and noncardiac causes of mortality than those who were not prescribed statins. DOPPS data also show that statins are underprescribed relative to recent Kidney Disease Outcomes Quality Initiative guidelines. No guidelines have been established for analgesic use, but high pain levels self-reported by hemodialysis patients suggest opportunities for improved pain management strategies. Guidelines for analgesic use in dialysis patients may help balance improved quality of life against potential side effects of analgesics. Medical and patient questionnaires show that depression in hemodialysis patients is common, frequently underdiagnosed, usually untreated, and associated with increased rates of mortality and hospitalization. Calcium channel blockers were associated with improved primary graft patency, aspirin with improved secondary graft patency, and angiotensin-converting enzyme inhibitors with improved secondary fistula patency. All 3 medications were associated with significantly decreased relative risk for access failure. There is large country variation in multivitamin use, with significantly higher use in the United States compared with Europe and Japan. Patients taking multivitamins had lower mortality risk than patients not taking multivitamins. Conclusion: DOPPS findings on medications indicate that prospective trials are needed before guidelines can be developed for appropriate medication use in these different therapeutic categories.

Two initiatives were launched in the closing years of the past century with the goal of improving the treatment outcomes of patients with kidney failure: the Kidney Disease Outcomes Quality Initiative, which formed expert panels to develop evidence-based clinical practice guidelines, and the Dialysis Outcomes and Practice Patterns Study (DOPPS), which now gathers data on practice patterns in dialysis facilities in 12 countries, including the United States. Recently, the Kidney Disease: Improving Global Outcomes (KDIGO) program was established to promote worldwide coordination and integration of initiatives to develop and implement clinical practice guidelines and provides new opportunities of cooperation with the international scope of the DOPPS. Collaboration between the DOPPS and KDIGO will lead to broader dissemination of relevant information to nephrologists, health care providers, and patients. Linking the DOPPS scope of work with the KDIGO goals will help develop continuous quality improvement programs and the provision of direct feedback to participating dialysis centers throughout the world. This will establish an essential component in the translation to clinical practice of evidence-based guidelines worldwide.

Analyses based on the National Cooperative Dialysis Study (NCDS) provided the impetus for routine quantification of delivered dialysis dose in hemodialysis practice throughout the world, by suggesting minimum targets for small solute (urea) clearance. Morbidity and mortality in dialysis populations remain high despite many technological advances in dialysis delivery. A number of observational studies reported association between higher dose of dialysis as measured by Kt/V urea or urea reduction ratio with lower mortality risk. During the 1990s, a steady increase in dialysis dose and a modest reduction in mortality on dialysis were observed. However, observational studies only reveal associations and are limited by selection bias and confounding. The Kidney Disease Outcomes Quality Initiative guidelines on dialysis adequacy are based on results of observational studies and expert opinion. Since the NCDS, the HEMO Study was the first major randomized clinical trial designed to study the effect of dose of dialysis and dialyzer flux on patient outcomes. Despite adequate separation of dose and flux, however, results of the trial did not prove a beneficial effect of higher dose. The Dialysis Outcomes and Practice Patterns Study (DOPPS), in a major international effort designed to examine the effect of practice patterns on outcomes, has made significant contributions to the topic of dialysis dose. The following review critically examines data from observational studies, including the DOPPS, and from the HEMO Study, emphasizing important lessons from both, and discusses future paradigms for achieving dialysis adequacy to improve patient outcomes.

The standardized mortality ratio (SMR) has been used to provide information about adjusted survival outcomes at dialysis facilities. There has been concern that high rates of transplantation could unjustly lead to unfavorable SMR profiles for individual dialysis units because healthier patients would be removed from dialysis therapy, leaving less healthy patients in the dialysis pool. We correlated 1999 overall adjusted SMR and 1999 standardized transplantation ratio (STR) weighted for mortality patient count and count of first transplantations of patients younger than 65 years. A total of 2,362 facilities were included in analyses. We found no correlation between rates of transplantation (by STR) and overall mortality profile (by SMR) based on Pearson's correlation coefficients ( r ), either unweighted, weighted by number of patients included in the 1999 mortality calculation (SMR), or weighted by number of patients included in the 1999 transplantation calculation ( r = −0.016, r = −0.015, and r = −0.015, respectively; P > 0.40 for each). Sensitivity analyses using SMR and STR over 3- and 3.5-year periods (January 1997 to June 2000) also showed no correlation between SMR and STR, respectively. We conclude that reported standardized rates for transplantation do not correlate with those reported for mortality by dialysis facilities. © 2002 by the National Kidney Foundation, Inc.

With improving survival and a decreasing probability of receiving a transplant, patients with end-stage renal disease (ESRD) are more likely to remain on hemodialysis therapy for more years than in the past. This study evaluates the effect of years on dialysis (vintage) on relative risk (RR) for death with and without adjustment for comorbidities and treatment factors. It also compares characteristics of patients on hemodialysis therapy for 7 years or longer with those on hemodialysis therapy for 1 to 7 years. Data were combined from two special US Renal Data System studies, the Case Mix Adequacy Study and Waves 1, 3, and 4 of the Dialysis Mortality and Morbidity Study. Excluding the first year of dialysis, 12,687 patients were studied during a 2-year follow-up, censoring at transplantation or loss to follow-up. Unadjusted analysis (vintage 1 to2 years as referent) showed that the risk for death remained nearly the same until the end of year 7 of dialysis therapy, after which the risk decreased significantly. However, with adjustment for demographics, comorbidities, and treatment factors, vintage was significantly associated with increased mortality risk during years 2 to less than 8 (RR = 1.12 to 1.30; P0.05). Vintage was independently associated with increased adjusted mortality among patients with and without diabetes until approximately 6 to less than 8 years of dialysis therapy. Patients on dialysis therapy for 7 years or longer were significantly (P0.05) more likely to be women, younger, and have lower phosphorus levels, higher hematocrits, and higher delivered dialysis doses. We conclude that adjusted mortality risk does not decrease with years on dialysis therapy, and modifiable factors deserve greater attention to improve survival among patients with ESRD with and without diabetes treated by hemodialysis.

Vascular access complications are common in hemodialysis patients. To investigate whether the use of angiotensin-converting enzyme (ACE) inhibitors influences the rate of polytetrafluoroethylene (PTFE) graft complications, we compared the rate of intervention-free graft survival among patients treated versus not treated with ACE inhibitors. We retrospectively analyzed the survival of grafts placed at our institution between January 1, 1995, and October 31, 1999. Among 121 grafts, 25 grafts were placed in 19 patients treated with ACE inhibitors and 96 grafts were placed in 68 patients not treated with ACE inhibitors. Follow-up ranged from 1 month to 5 years. Ten of 25 grafts failed in the ACE-inhibitor group and 62 of 95 grafts failed in the non-ACE-inhibitor group. Actuarial intervention-free access survival rates (Kaplan-Meier) were significantly greater in the ACE-inhibitor than non-ACE-inhibitor group (71% versus 53% at 6 months, 58% versus 35% at 12 months, and 44% versus 22% at 24 months; P = 0.04). Using a Cox model adjusting for age, race, sex, and diabetes, the relative risk (RR) for access failure in the ACE-inhibitor group was 53% less than in the non-ACE-inhibitor group (RR, 0.47; p0.03). In a more complex Cox model with additional adjustment for comorbid conditions, the RR was even lower (RR, 0.32; P = 0.003) for the ACE-inhibitor compared with non-ACE-inhibitor group (reference = 1.00). The lower RR was observed for patients with and without congestive heart failure. These results suggest that ACE inhibitors offer clinical promise in the prevention of PTFE graft failure. A prospective randomized trial is warranted to confirm the benefit of ACE inhibitors.

Dialyzer reuse is practiced in more than 75% of the patients and dialysis units in the United States. However, reuse is not practiced in a small fraction of patients treated in reuse units (RUUs). This study evaluates both patient and facility characteristics associated with nonreuse in RUUs. The data source is from the Dialysis Mortality and Morbidity Study, Waves 1, 3, and 4, of the US Renal Data System. Only facilities that practiced dialyzer reuse were included in the analysis. A total of 12,094 patients from 1,095 reuse facilities were studied. Patients undergoing hemodialysis as of December 31, 1993, were selected. Of all patients treated in RUUs, 8% did not reuse dialyzers. Nonreuse was significantly (P0.02) more common, based on adjusted odds ratios (ORs), among patients who were younger (OR = 1.16 per 10 years younger), had primary glomerulonephritis (OR = 1.26 versus diabetes), had lower serum albumin level (OR = 1.72 per 1 g/dL lower), had more years on dialysis, and had higher level of education. Nonreuse patients were more likely to be treated with low-flux dialyzers (OR = 7.35; P0. 0001) and have a lower dialysis dose. No reuse was more likely in larger units and in not-for-profit and hospital-based units. Patient refusal accounted for one fourth of nonreuse in RUUs and was associated with the same factors, as well as with fewer comorbid conditions and non-Hispanic ethnicity. Significant geographic variations (up to eightfold) were documented. Nonreuse patients are treated with smaller, low-flux dialyzers and, on average, receive a lower Kt/V than reuse patients in the same units.

This national study compares waitlisting and transplantation rates by gender, race, and diabetes and evaluates physiologic factors (panel-reactive antibodies [PRA], blood type, HLA matchability) and related practices (early and multiple waitlisting) as explanatory factors. This longitudinal study of the time to transplant waitlisting among 228,552 incident end-stage renal disease (ESRD) dialysis patients and to cadaveric transplantation among 46,164 waitlist dialysis patients (n = 23,275 first cadaveric transplants) used US data for 1991 to 1997. Relative rates of waitlisting (RRWL) after ESRD onset and of cadaveric transplantation (RRTx) after waitlist (Cox proportional hazards models) were adjusted for age, race, sex, ESRD cause, region, and incidence/waitlist year. We found that women have an RRWL = 0.84 (P < 0.0001) and RRTx = 0.86 (P < 0. 0001). PRA levels can explain the difference in the transplantation rate, because accounting for PRA gives an adjusted RRTx = 0.98 (NS) for women. For blacks versus whites, the RRWL = 0.59 (P < 0.0001) and RRTx = 0.55 (P < 0.0001). However, the transplantation rate can only partly be explained by ABO types, rare HLA types, and early and multiple waitlisting (adjusted RRTx = 0.67 [P < 0.0001]). For diabetes versus glomerulonephritis, the RRWL = 0.52 (P < 0.0001) and RRTx = 0.98 (NS). Older patients (40 to 59 years of age) are less likely to be waitlisted and to receive a transplant after waitlisting (RRWL = 0.57 [P < 0.0001], RRTx = 0.88 [P < 0.0001]) versus younger patients (ages 18 to 39 years). These results indicate substantial differences by age, sex, race, and diabetes in rates of waitlisting for transplantation and by age and race for transplantation after waitlisting. These differences by race were not explained by referral practices or the physiologic factors studied here.

Hyperphosphatemia is a predictable consequence of chronic renal failure and is present in most patients on dialysis. Traditionally, the risk associated with elevated serum phosphorus has focused on its impact on renal osteodystrophy. A growing body of evidence, however, suggests that abnormalities in serum phosphorus, calcium-phosphorus product (CaxP), and parathyroid hormone (PTH) levels are resulting in vascular and visceral calcification, thereby contributing to the substantially increased risk of cardiovascular death in this population. In this analysis, we review in detail the literature that describes these associations. We show that the current treatment paradigm for serum phosphorus and secondary hyperparathyroidism is ineffective for a large segment of dialysis patients. Currently, 60% of hemodialysis patients have phosphorus greater than 5.5 mg/dL, and 40% have CaxP greater than 60 mg(2)/dL(2). It is our belief that prevention of uremic calcification, cardiac death, and vascular disease should assume primary importance when evaluating the risks associated with elevated levels of phosphorus, CaxP, and PTH. We recommend that target levels should become 9.2 to 9.6 mg/dL for calcium, 2.5 to 5.5 mg/dL for phosphorus, less than 55 mg(2)/dL(2) for CaxP product, and 100 to 200 pg/mL for intact PTH.

Author(s): Saran, Rajiv; Li, Yi; Robinson, Bruce; Abbott, Kevin C; Agodoa, Lawrence YC; Ayanian, John; Bragg-Gresham, Jennifer; Balkrishnan, Rajesh; Chen, Joline LT; Cope, Elizabeth; Eggers, Paul W; Gillen, Daniel; Gipson, Debbie; Hailpern, Susan M; Hall, Yoshio N; He, Kevin; Herman, William; Heung, Michael; Hirth, Richard A; Hutton, David; Jacobsen, Steven J; Kalantar-Zadeh, Kamyar; Kovesdy, Csaba P; Lu, Yee; Molnar, Miklos Z; Morgenstern, Hal; Nallamothu, Brahmajee; Nguyen, Danh V; O'Hare, Ann M; Plattner, Brett; Pisoni, Ronald; Port, Friedrich K; Rao, Panduranga; Rhee, Connie M; Sakhuja, Ankit; Schaubel, Douglas E; Selewski, David T; Shahinian, Vahakn; Sim, John J; Song, Peter; Streja, Elani; Kurella Tamura, Manjula; Tentori, Francesca; White, Sarah; Woodside, Kenneth; Hirth, Richard A

A number of studies have suggested that type of dialysis membrane is associated with differences in long-term outcome of patients undergoing hemodialysis, both in terms of morbidity and mortality. The purpose of this study was to determine the relationship of membrane type and specific causes of death. Data from the United States Renal Data System Case Mix Adequacy Study, a national random sample of hemodialysis patients who were alive on December 31, 1990, were used. Our study was limited to patients in this data set who were undergoing dialysis for at least 1 year (n = 4,055). For the main analytic models, membrane type was classified into two categories: unmodified cellulose or MC/SYN (which combines modified cellulose [MC] and synthetic membranes [SYN]). The relationships of membrane type and major causes of mortality were analyzed using Cox proportional hazards models, which adjusted for multiple (21) covariates, including demographics, comorbidity, Kt/V, and other parameters. Patients were censored at transplantation or 60 days after a switch to peritoneal dialysis. Compared with patients dialyzed with unmodified cellulose membranes, the adjusted relative mortality risk (RR) from infection was 31% lower (RR = 0.69; P = 0.03) and from coronary artery disease was 26% lower (RR = 0.74; P = 0.07) for patients dialyzed with MC/SYN membranes. No statistically significant difference (all P > 0.1) was found in mortality risk from cerebrovascular disease (RR = 1.08), other cardiac causes (RR = 0.86), malignancy (RR = 0.90), or other known causes (RR = 0.82) between patients dialyzed with MC/SYN compared with unmodified cellulose membranes. These results offer support to reported experimental and observational clinical studies that have found that unmodified cellulose membranes may increase the risk for both infection and atherogenesis. Further studies are necessary to evaluate the possibility of confounding factors, compare more specific membrane types, and determine the pathophysiology linking membrane type to cause-specific mortality.

Since its introduction in the United States more than two decades ago, the practice of dialyzer reuse has continued to grow. In recent years, it appears to have been based mainly on economic, rather than medical, considerations. However, adverse reactions, such as immune hemolytic anemia caused by anti-Nform antibody associated with dialyzer reuse, and infectious outbreaks have been reported. The validity of earlier reports suggesting improved morbidity and mortality in patients dialyzed with reprocessed dialyzers have been disputed with recent data. In the current Dialysis Morbidity and Mortality Study (DMMS), we collected demographic, comorbidity, laboratory, treatment, socioeconomic, and insurance data on a large random sample of approximately 20,000 of the US dialysis patient population over a 3- year period, using the dialysis records. Data were collected predominantly on patients receiving incenter hemodialysis as of December 31, 1993. Morbid and mortal events through 1996 were examined in relation to various patient and dialysis unit characteristics. The results show that there has been a significant increase in the practice of dialyzer reuse in the United States. Large regional differences exist, and reuse is greatest in freestanding for-profit (FSFP) units (87%) and freestanding nonprofit (FSNP) units (77%) and least in hospital units (49%). There has been a significant increase in the proportion of units using Renalin (Minntech, Minneapolis, MN) and a substantial decrease in the proportion of the units using formalin. Approximately 15% of the units each year switch the type of sterilant. (Am J Kidney Dis 1998 Dec;32(6 Suppl 4):S88-92)

Noncompliance with hemodialysis (HD), depending on the definition, occurs in 2% to more than 50% of patients. To better understand predictors and outcomes of noncompliance, we evaluated patient characteristics associated with noncompliance and the impact of noncompliance on survival. Using data from two USRDS special studies, we identified 6,251 patients who were on dialysis for more than 1 year for inclusion in this study. Noncompliance was defined in four ways: skipping one or more HD sessions in a month, shortening by 10 or more minutes one or more HD sessions in a month, an interdialytic weight gain (IWG) of more than 5.7% of dry weight, or a serum phosphate (PO4) of greater than 7.5 mg/dL. Sociodemographic predictors of noncompliance were identified using logistic regression. Survival analysis was done using Cox proportional hazards models with adjustments for sociodemographics, comorbid conditions, and dose of HD. Overall, 8.5% of patients skipped HD, 20% shortened HD (7% three or more times), 10% had more than a 5.7% IWG, and 22% had a PO4 greater than 7.5. There was a significant correlation among the measures of noncompliance. Blacks (adjusted odds ratio [AOR] = 2.10), patients aged 20 to 39 years (AOR = 1.62), and smokers (AOR = 1.34) were significantly more likely to skip HD than whites, patients aged 40 to 59 years, and nonsmokers, respectively (P0.01 for each). Similar results were seen for the other measures of noncompliance, except for PO4, in which blacks were significantly less likely to be noncompliant (NC) (AOR = 0.85, P0.05). Compared with compliant patients, those who skipped one or more HD sessions in a month had a 25% higher risk of death (P0.01). Those who had greater than a 5.7% IWG had a 35% higher risk of death (P0.001), whereas those with a PO47.5 had a 13% higher risk of death (P0.05). Overall, patients who shortened HD sessions did not have a higher risk of death, but those who shortened three or more in 1 month had a 20% higher risk of death (P0.05). Compliance with a medical regimen is a complex issue. Noncompliance in HD often, but not always, is associated with a higher risk of an adverse outcome. This is a US government work. There are no restrictions on its use.

A strong association exists between nutritional status and morbidity and mortality in patients with end-stage renal disease who are treated with hemodialysis. Described here is the predictive value for mortality over 5 years of follow-up of a number of risk factors, recorded at baseline, in a national sample of 3,607 hemodialysis patients. Among the variables studied were case-mix covariates, caregiver classifications of nutritional status, serum albumin concentration, and body mass index (BMI). The Case Mix Adequacy special study of the United States Renal Data System (USRDS) provided these measurements as of December 31, 1990. The USRDS patient standard analysis file provided follow-up data on mortality for all patients through December 31, 1995, by which time 64.7% of the patients had died. BMI is a simple anthropometric measurement that has received little attention in dialysis practice. Caregiver classification refers to documentation in a patient's dialysis facility medical records that stated an individual to be "undernourished/cachectic," "obese/overweight," or "well- nourished." The mean serum albumin was 3.7 +/- 0.45 (SD) g/dL, and the mean BMI was 24.4 +/- 5.3 (SD) kg/m2. By caregiver classification, 20.1% of patients were undernourished, and 24.9% obese. In hazard regression models, including but not limited to the Cox proportional hazards model, low BMI, low serum albumin, and the caregiver classification "undernourished" were independently and significantly predictive of increased mortality. In analyses allowing for time- varying relative mortality risks (ie, nonproportional hazards), the greatest predictive value of all three variables occurred early during follow-up, but the independent predictive value of baseline serum albumin and BMI measurements on mortality risk persisted even 5 years later. No evidence of increasing mortality risk was found for higher values of BMI. Serum albumin was confirmed to be a useful predictor of mortality risk in hemodialysis patients; BMI was established as an independently important predictor of mortality; both serum albumin and BMI, measured at baseline, continue to possess predictive value 5 years later; the subjective caregiver classification of nutritional status "undernourished" has independent value in predicting mortality risk beyond the information gained from two other markers of nutritional status–BMI and serum albumin. (Am J Kidney Dis 1998 Jun;31(6):997-1006)

Elevated serum phosphorus is a predictable accompaniment of end-stage renal disease (ESRD) in the absence of dietary phosphate restriction or supplemental phosphate binders. The consequences of hyperphosphatemia include the development and progression of secondary hyperparathyroidism and a predisposition to metastatic calcification when the product of serum calcium and phosphorus (Ca x PO4) is elevated. Both of these conditions may contribute to the substantial morbidity and mortality seen in patients with ESRD. We have analyzed the distribution of serum phosphorus in two large national, random, cross-sectional samples of hemodialysis patients who have been receiving dialysis for at least 1 year. Data were obtained from two special studies of the United States Renal Data System, the Case Mix Adequacy Study (1990) and the Dialysis Morbidity and Mortality Study Wave 1 (1993). The relative risk of death by serum phosphorus quintiles is described after adjusting for age at onset of ESRD, race, sex, smoking status, and the presence of diabetes, the acquired immunodeficiency syndrome, and/or neoplasm. Logistic regression analysis is then used to describe the demographic, comorbid, and laboratory parameters associated with high serum phosphorus. Serum phosphorus was similar in these two study populations and averaged 6.2 mg/dL. Ten percent of patients had levels greater than 9 mg/dL and at least 30% of each group had serum phosphorus levels greater than 7 mg/dL. The adjusted relative risk of death by serum phosphorus level was not uniform across all quintiles, being constant below a level of 6.5 mg/dL and increasing significantly above this level. The relative risk of death for those with a serum phosphorus greater than 6.5 mg/dL was 1.27 relative to those with a serum phosphorus of 2.4 to 6.5 mg/dL. This increased risk was not diminished by statistical adjustment for coexisting medical conditions, delivered dose of dialysis, nutritional parameters, or markers of noncompliance. Evaluation of predictors of serum phosphorus greater than 6.5 mg/dL revealed in multivariate analysis that younger age at onset of ESRD, female sex, white race, diabetes, active smoking, and higher serum creatinine levels were all significant predictors. Analysis of serum calcium revealed no correlation with relative risk of death. The Ca x PO4 product, however, showed a mortality risk trend similar to that seen with serum phosphorus alone. Those in the highest quintile of the Ca x PO4 product (>72 mg2/dL2) had a relative mortality risk of 1.34 relative to those with products of 42 to 52 mg2/dL2. The relative mortality risk by log parathyroid hormone (PTH) level was elevated for patients with higher levels, but the mortality risk associated with hyperphosphatemia was independent of PTH. For hemodialysis patients who have been receiving dialysis for at least 1 year, we conclude that a large percentage have a serum phosphorus level above 6.5 mg/dL and that this places them at increased risk of death. This increased risk is independent of PTH. The mechanism(s) responsible for death is unknown, but may be related to an abnormally high Ca x PO4 product. Although mechanisms are not clearly established, this study supports the need for vigorous control of hyperphosphatemia to improve patient survival.

Vascular access failure causes substantial morbidity to hemodialysis patients. We sought to identify factors determining survival of the permanent vascular access in use at the start of end-stage renal disease during 1990 in a national sample of 784 incident hemodialysis patients insured by Medicare. Medicare claims records were used to identify access failures or revisions among patients with an arteriovenous (AV) fistula (n = 245) and an AV vascular graft (n = 539). A proportional hazards analysis of time to first failure or revision, controlled by stratification for sex, race, and cause of end-stage renal disease, was used to determine the effect of age, access type, and peripheral vascular disease on vascular access survival. Patients with an AV fistula and who were older than 65 years had a risk of access failure that was 24% lower than similar patients with an AV graft (P < 0.02). The relative risk of access failure for an AV fistula, but not an AV graft, varied significantly with age for patients younger than 65 years (P < 0.01). The relative risk of access failure for a patient with an AV fistula, compared with a patient of the same age with an AV graft, was 67% lower at the age of 40 years, 54% lower at the age of 50 years, and 24% lower at the age of 65 years. A history of peripheral vascular disease was associated with a 24% higher risk of AV graft or fistula failure (P = 0.05). Measures to decrease vascular access-related morbidity among hemodialysis patients should include reversing the current trend toward increasing use of AV grafts, particularly in patients younger than 65 years.

Renal allograft survival of organs from living-related donors (LRDs) is superior to that of organs from cadaveric donors (CAD). Allograft survival rates are lower in black recipients of both CAD and LRD transplants compared with recipients of other races. It is not known whether the superior donor effect of LRD varies between races. We investigated the graft survival outcome of first renal transplants performed in the United States in 1986 and 1989 to determine whether the donor effect differs between black and white recipients. A measurement of "donor type effect" is introduced. There were 7,002 and 7,307 first renal transplants in 1986 and 1989, respectively, for which allograft survival data were available from the United States Renal Data Systems. Both black and white recipients showed a greater than 50% reduction in the risk of allograft loss at all the points studied up to 5 years posttransplant when LRD was chosen over CAD transplantation. A measurement of donor type effect indicates that graft loss is reduced by 7 to 21 percentage points at 1 and 5 years posttransplant. The donor type effect is proportionally equal in both races. Therefore, kidney donation from living relatives as a first transplant should be encouraged for all medically suitable end-stage renal disease patients as a means of improving outcome and reducing CAD transplantation waiting time for patients in whom LRD transplants cannot be performed.

To describe the joint effects of race and age on the risk of end-stage renal disease (ESRD) attributed to hypertension (ESRD-HT), we analyzed data for white and black adults, 20 to 84 years of age, reported by the United States Renal Data System during the period 1987 to 1990. The risk of ESRD-HT increased substantially with age for both blacks and whites; however, at each age, the risk was greater for blacks. A more in-depth description of the combination of effects involving race and age on ESRD-HT incidence was provided by two models of joint effects, one additive and the other multiplicative. Both models used the 20- to 24-year age group as the referent. Under the additive model the risk of ESRD-HT in blacks attributable to the joint effects between race and age increased continuously from younger to older groups. This indicates that although ESRD-HT risk increases with age for both blacks and whites, the increase for blacks is greater than expected if the effects of race were independent of the effects of age. However, the multiplicative model indicated that the proportional increase with age in ESRD-HT risk among blacks, as compared with whites, was more striking for younger ages (≤50 years among women and ≤40 years among men), and especially so for men. This suggests a more accelerated course of hypertension toward ESRD for blacks (especially younger men) than for whites. A conceptual model to explain these patterns of race-age joint effects is proposed. The model considers two pathogenic patterns of progression to ESRD among hypertensive patients: (1) a rapidly progressive disease, particularly for younger black men, and (2) a slower progressive disease that culminates in ESRD at older ages. The implications of this conceptual model for future research, and the empirical findings on which it is based, are discussed.

In view of the relatively low mortality risk on dialysis and the high risk of allograft loss among black compared with white end-stage renal disease (ESRD) patients, we studied the relative mortality risks of all black renal transplant candidates in Michigan from 1984 to 1989. There were 770 black ESRD patients followed from wait-listing for cadaveric (CAD) kidney transplantation until the time of transplantation, death, or December 31, 1989. The time on dialysis prior to wait-listing exceeded 1 year in 24% of these patients. Black diabetic patients on the waiting list have more than twofold relative mortality risk (RR) compared with nondiabetic individuals (RR = 2.73, P0.001) while the RR by diabetes status among CAD transplant recipients was small. Overall, CAD transplantation was associated with elevated risk of mortality in the first month posttransplantation (RR = 3.39, P0.03). Cadaveric donor transplant and wait-listed dialysis patients have equal death rates 112 days after transplantation. Thereafter, death rates were lower for transplant recipients compared with transplant candidates on dialysis. One year after transplantation, CAD transplant recipients on the average have approximately half the risk of death compared with dialysis patients who remain on the waiting list (RR = 0.49, P0.03). The cumulative survival probabilities are superior in transplant recipients just beyond 1 year after transplantation. Therefore, CAD transplantation in black ESRD patients is associated with a high risk of mortality in the early period after transplantation. Beyond 1 year, black transplant recipients have a substantial survival advantage over corresponding dialysis patients on the waiting list.

With the development of recombinant human erythropoietin, clinicians can now treat the anemia of chronic renal failure patients. Although most attention has focused on patients with end-stage renal disease, erythropoietin is also prescribed to anemic renal patients before the initiation of dialysis therapy. This study presents the first objective estimate of the size of the US population with predialysis renal insufficiency and the fraction of those patients who also have anemia. The study used population-based data from the second National Health Nutrition Examination Survey (NHANES II), conducted between 1976 and 1980. Participants underwent interviews, standardized physical examinations, and blood testing, including hematocrit and serum creatinine (N = 25,286 who were surveyed, 10,453 who underwent laboratory testing). Our estimates were based on the following methodology: (1) selecting predialysis renal insufficiency patients aged 12 to 74 years from the NHANES II survey, (2) adjusting for population changes between 1978 and 1988, (3) adding estimates for pediatric and geriatric populations, (4) projecting results to 1990, and (5) excluding nonanemic patients. The NHANES II survey included 44 patients with serum creatinine values greater than 2.0 mg/dL and less than 8.0 mg/dL. This yielded an estimate of 648,000 to 708,000 persons in 1990 with predialysis renal insufficiency. Data from both the NHANES II survey and the literature demonstrate that the percent of patients with anemia varies by serum creatinine level. All total, the study estimated that in 1990 there were between 68,000 and 75,000 individuals with predialysis renal insufficiency who also had anemia. However, several limitations of the methodology suggest that these values overestimate the true population numbers. Moreover, since the study was based on a population sample, the total number receiving medical care was probably significantly lower. Identification of those patients may lead to better treatment of their renal insufficiency and anemia.

Blood type O recipients of cadaveric renal transplants have longer pretransplant waiting periods than blood type A, B, and AB recipients. To evaluate reasons for and consequences of this discrepancy, we studied both the frequency of various donor and recipient blood type combinations and their outcomes. Among 37,659 cadaveric renal transplants performed during 1983 through 1989, there were 2,625 transplants (7%) received by patients of compatible but nonidentical blood types. Of 18,575 type O donor organs, 16,784 were received by type O patients for a recipient to donor ratio of 0.9. The corresponding ratios were greater than 1.0 for all other blood types (1.02 for blood type A, 1.14 for type B, and 2.18 for type AB). This causes blood type O patients to have a lower access to transplantation and to have significantly longer waiting times than patients of all other blood types. This inequality of access diminished significantly (P less than 0.001) over the years, but did not resolve by 1989. Analysis of relative risk for first graft loss by multiple regression (Cox) showed that transplantation across compatible blood types had a 9.1% higher risk (P less than 0.1) than that of transplantation among identical blood types. Cadaveric renal transplantation within identical blood types optimizes access to transplantation and avoids further aggravating past disadvantages for blood type O recipients.

To evaluate the rate and associated factors for recovery of renal function in patients labeled by their nephrologists as having end-stage renal disease (ESRD), the data base of the Michigan Kidney Registry was used. All patients reported as starting treatment for ESRD between 1976 and 1985 (N = 7,404) were evaluated, excluding patients with acute tubular necrosis (ATN) or transplantation cases. While patients with ESRD due to diabetes and cystic diseases had lower recovery rates than average, patients with glomerulonephritis associated with a systemic illness, vasculopathies, and crescents had threefold to fourfold higher recovery rates. White race, older age, and later year of ESRD were associated with significantly higher recovery rates. Recovery rates did not differ substantially for patients receiving peritoneal dialysis or hemodialysis. Recovery occurred within 6 months of ESRD in approximately 48% of those recovering, 74% within 1 year, and lasted at least 1 year in 75% of the cases. The authors conclude that caution should be applied when the diagnosis of ESRD is made; the possibility of recovery should be sought and assessed, especially when early renal transplantation is considered.

Using data from the Michigan Kidney Registry, the survival of patients with end-stage renal disease (ESRD) was evaluated by multivariate analysis. Black patients had a significantly better outcome overall. A significantly worse outcome was found for older patients and diabetics, among both races and for black females. Causes of death were analyzed for dialysis patients and specific comments address discontinuation of dialysis leading to death.

Uremic patients frequently have low baseline temperatures and a blunted febrile response to infection. We investigated the first step in the generation of a febrile response, the production of leukocytic pyrogen (LP) by blood monocytes, in 12 patients on chronic hemodialysis, five patients on continuous ambulatory peritoneal dialysis (CAPD), and 17 control subjects. No significant differences were found in the amount of LP produced by hemodialysis patients, CAPD patients, and control subjects. Uremic serum did not decrease LP production by monocytes from control subjects. Hemodialysis patients who were consistently hypothermic (mean oral predialysis temperature less than or equal to 35.6 degrees F) produced as much LP as those with more normal oral temperatures (mean oral predialysis temperature greater than or equal to 36.8 degrees F). Decreased production of LP does not explain the blunted febrile response noted in patients with chronic renal failure.

Actuarial survival analysis of 889 cadaver transplant patients between 1972 and 1981 in Michigan reveals functional graft (P = .0003) and patient (P = .004) survivals are improved when donors and recipients are of the same race (black or white). The Cox regression model for multifactorial analysis confirms the significantly lower graft survival for the mixed racial combination group with a relative risk of 1.27 (P less than .05). By this analysis, other significant factors adversely affecting the graft survival rates include diabetes as a cause of end-stage renal disease, earlier date of transplantation, shorter duration of prior dialysis, and a significant center effect. Patient survival has a significantly greater relative risk for the black to white racial combination, diabetes, earlier calendar year of transplantation, and age of patient. While the mixed racial group was slightly older (delta = 2 years), had more hypertension, less glomerulonephritis, and more HLA mismatches, our analysis by the Cox regression model suggests that these factors played only minor roles (P greater than .05) regarding graft survival rates. Therefore, our data suggest that independent of several other factors, cadaver kidneys have a better functional outcome when they are transplanted into recipients of the same race.