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Presents several studies on hypertension and systemic disease. Alternatives to measuring ambulatory pressure; Analysis of the extent of microvascular injury characterized by fragmented red blood cells in the mesangium of glomeruli in diabetic nephropathy; Effectiveness of percutaneous transluminal angioplasty in renal artery stenosis; Effects of stent placement for renal artery stenosis on the function of treated and contra-lateral kidneys.

Background: Patients with ESRD are at increased risk for heart valve calcification. It has not been established whether hospitalized valvular heart disease (VHD) is a substantial barrier to renal transplantation (RT) after transplant listing, or whether VHD progresses after RT., Methods: Using data from the USRDS, we studied 35,215 patients with ESRD enrolled on the renal transplant waiting list from July 1994 to June 1997. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for RT and VHD., Results: In comparison to maintenance dialysis (2.2/1,000 person years), RT was independently associated with a lower hazard for hospitalization for VHD (0.7/1,000 person years, HR 0.28, 95% confidence interval 0.17 - 0.47). Renal transplant recipients had much lower rates of VHD after transplant than before (rate ratio (RR) 0.49, 95% Cl 0.47 - 0.52). Patients with VHD were significantly less likely to receive RT (adjusted rate for RT 0.38, 95% CI 0.20 - 0.45) but patients who received valve replacement surgeries (VRS) were not affected (adjusted rate for RT 1.10, 95% CI 0.52 - 2.32, not significant)., Conclusions: VHD is an uncommon but serious barrier to RT after listing, while VRS is not a significant barrier to RT. Established VHD does not appear to worsen after RT. Clinicians should consider giving increased attention to the detection and treatment of VHD during the pre-transplant evaluation.

Background: The patient characteristics, including age at presentation to end-stage renal disease (ESRD) and mortality associated with sickle cell nephropathy (SCN) have not been characterized for a national sample of patients., Methods: 375,152 patients in the United States Renal Data System were initiated on ESRD therapy between January 1, 1992 and June 30, 1997 and analyzed in an historical cohort study of SCN., Results: Of the study population, 397 (0.11%) had SCN, of whom 93% were African-American. The mean age at presentation to ESRD was 40.68+/-14.00 years. SCN patients also had an independently increased risk of mortality (hazard ratio 1.52, 95% CI: 1.27-1.82) even after adjustment for placement on the renal transplant waiting list, diabetes, hematocrit, creatinine, and body mass index. However, when receipt of renal transplantation was also included in the model, SCN was no longer significant (p = 0.51, HR = 1.10, 95% CI: 0.82-1.48). SCN patients were much less likely to be placed on the renal transplant waiting list or receive renal transplants in comparison to age and race matched controls, and results of survival analysis were similar in this model., Conclusions: SCN patients were much less likely to be listed for or receive renal transplantation than other comparable patients with ESRD. SCN patients were at independently increased of mortality compared with other patients with ESRD, including those with diabetes, but this increased risk did not persist when models adjusted for their low rates of renal transplantation.

Background: The patient characteristics and mortality associated with autosomal dominant polycystic kidney disease have not been characterized for a national sample of end-stage renal disease (ESRD) patients., Methods: 375,152 patients in the United States Renal Data System were initiated on ESRD therapy (including patients who eventually received renal transplants) between January 1, 1992 and June 30, 1997 and analyzed in an historical cohort study of polycystic kidney disease., Results: Of the study population, 5,799 (1.5%) had polycystic kidney disease. In logistic regression, polycystic kidney disease was associated with Caucasian race (odds ratio 3.31, 95% CI, 3.09-3.54), women (1.10, 1.04-1.16), receipt of renal transplant (4.15, 3.87-4.45), peritoneal dialysis (vs. hemodialysis, 1.37, 1.27-1.49), younger age, and more recent year of first treatment for ESRD. Use of pre-dialysis EPO but not the level of serum hemoglobin at initiation of ESRD was significantly higher in patients with polycystic kidney disease. Patients with polycystic kidney disease had lower mortality compared to patients with other causes of ESRD, but patients with polycystic kidney disease had a higher adjusted risk of mortality associated with hemodialysis (vs. peritoneal dialysis) compared to patients with other causes of ESRD (hazard ratio 1.40, 1.13-1.75)., Conclusions: Hematocrit at presentation to ESRD was not significantly different in patients with polycystic kidney disease compared with patients with other causes of ESRD. Peritoneal dialysis is a more frequent modality than hemodialysis in patients with polycystic kidney disease, and patients with polycystic kidney disease had an adjusted survival benefit associated with peritoneal dialysis, compared to patients with other causes of renal disease.

Aims: Hospitalized fungal infections are reported frequently in renal transplant recipients and peritoneal dialysis patients, but the frequency of hospitalized fungal infections in dialysis patients has not been studied in a national population., Methods: 327,993 dialysis patients in the United States Renal Data System initiated from January 1, 1992 to June 30, 1997 were analyzed in a retrospective registry study of fungal infections (based on ICD9 Coding)., Results: Dialysis patients had an age-adjusted incidence ratio for fungal infections of 9.80 (95% confidence interval (CI) 6.34-15.25)) compared to the general population in 1996 (the National Hospital Discharge Survey). Candidiasis accounted for 79% of all fungal infections, followed by cryptococcosis (6.0%) and coccidioidomycosis (4.1%). In multivariate analysis, fungal infections were associated with earlier year of dialysis, diabetes, female gender, decreased weight and serum creatinine at initiation of dialysis, chronic obstructive lung disease and AIDS. In Cox regression analysis the hazard ratio for mortality of fungal infections was 1.35 (95% CI 1.28-1.42)., Conclusions: Dialysis patients were at increased risk for fungal infections compared to the general population, which substantially decreased patient survival. Female and diabetic patients were at increased risk for fungal infections. Although candidiasis was the dominant etiology of fungal infections, the frequency of cryptococcosis and coccidioidomycosis were higher than previously reported., (Copyright 2001 S. Karger AG, Basel)

Background: Risk factors for pulmonary embolism (PE) have been identified in the general population but have not been studied in a national population of renal transplant recipients., Methods: Therefore, 33,479 renal transplant recipients in the United States Renal Data System from 1 July 1994-30 June 1997 were analyzed in a historical cohort study of hospitalized PE (ICD9 Code 415.1x). HCFA form 2728 was used for comorbidities., Results: Renal transplant recipients had an incidence of PE of 2.26 hospitalizations per 1000 patient years at risk. In multivariate analysis, polycystic kidney disease (adjusted odds ratio, 4.44, 95% confidence interval, 2.31-8.53), older recipient age, higher recipient weight, cadaveric donation, history of ischemic heart disease, and decreased serum albumin were associated with increased risk of PE. Body mass index and hemoglobin were not significant. Kidney-pancreas transplantation was also not significant. In Cox Regression analysis PE was associated with increased mortality (hazard ratio 2.06, 95% CI 1.34-3.18)., Conclusions: The most important risk factors for PE in this population were polycystic kidney disease, advanced age and increased weight. The reasons for the increased risk of polycystic kidney disease remain to be determined but were independent of hematocrit level at initiation of end stage renal disease, and may result from venous compression. Prospective studies of anatomical and hemostatic changes after renal transplantation in recipients with polycystic kidney disease are warranted.

Background: The patient characteristics and course of HlV/AIDS-associated nephropathy (HIVAN) are presented for a national sample of end-stage renal disease (ESRD)., Methods: 375,152 patients in the United States Renal Data System were initiated on ESRD therapy between 1 January 1992 and 30 June 1997 and analyzed in an historical cohort study of HIVAN., Results: Of the study population, 3653 (0.97%) had HIVAN. Among patients with HIVAN, 87.8% were African American. HIVAN had the strongest association with African American race compared to other causes of renal failure except sickle cell anemia in logistic regression analysis (odds ratio 12.20, 95% confidence interval (CI) 10.57-14.07). In a separate logistic regression analysis, HIVAN was associated with male gender, decreased age (39.32 +/- 8.51 vs. 60.97 +/- 16.43 years, p<0.01 by Student's t-test), weight, body mass index, hemoglobin, albumin, decreased rate of pre-dialysis erythropoietin use, increased creatinine, decreased hypertension and increased rate of no medical insurance. The geographic distribution of HIVAN was similar to the distribution of HIV cases nationally. Two-year all cause unadjusted survival was 36% for HIVAN vs. 64% for all other patients with ESRD. HIVAN was associated with decreased patient survival in Cox regression analysis (hazard ratio for mortality 5.74, 95% CI, 5.40-6.10)., Conclusions: HIVAN had the strongest association with African American race of all causes of renal failure among patients on maintenance dialysis. HIVAN was associated with decreased patient survival after initiation of dialysis, which may be associated with poorer medical condition at initiation of dialysis.

Background: Patients with end stage renal disease (ESRD) are at increased risk for cardiovascular disease. We hypothesized that the clinical incidence of congestive heart failure (CHF) would be lessened after successful renal transplantation, as many of the metabolic and intravascular volume abnormalities associated with dialysis-dependent ESRD would resolve., Methods: Using data from the USRDS, we studied 11,369 patients with ESRD due to diabetes enrolled on the renal and renal-pancreas transplant waiting list from 1 July 1994-30 June 1997. Cox non-proportional hazards regression models were used to calculate adjusted, time-dependent hazard ratios (HR) for time to the most recent hospitalization for CHF (including acute myocardial infarction, unstable angina, or other CHF, ICD9 Code 428.x) for a given patient in the study period, controlling for both demographics and comorbidities in the medical evidence form (HCFA 2728)., Results: In comparison to maintenance dialysis, renal transplantation was independently associated with a lower risk for CHF (HR 0.64, 95% confidence interval, 0.54-0.77) in a model including age, gender, race, and year of first dialysis, but not in a model including comorbidities from the medical evidence form, although the sample was much smaller., Conclusions: Patients with ESRD due to diabetes on the renal transplant waiting list were much less likely to be hospitalized for congestive heart failure after renal transplantation, despite post transplant complications due to immunosuppression.

Aims: The patient characteristics and clinical course of nephropathy associated with multiple myeloma/light chain disease (MMN) has not been described for a national sample of end-stage renal disease patients., Methods: 375,152 patients in the United States Renal Data System were initiated on ESRD therapy between January 1, 1992 and June 30, 1997, and were analyzed in a retrospective registry study of MMN (PDIS=2030A, 2030B, 2030Z, and 203Z)., Results: Of the study population, 3298 (0.88%) had MMN. Patients with MMN were disproportionately male (59.5% vs. 53.2%) and Caucasian (76.2% vs. 64.1%, p < 0.01 by Chi-square for both comparisons) and older (68.00+/-11.78 vs. 60.69+/-16.55 years, p < 0.01 by Student's t-test). In logistic regression analysis, patients with MMN were more likely male and Caucasian, were older, had lower serum hemoglobin, higher creatinine, and more likely to have been started on hemodialysis than peritoneal dialysis. The two-year all-cause mortality of patients with MMN during the study period was 58% vs. 31% in all other patients (p < 0.01 by log rank test). In Cox regression, MMN was independently associated with decreased all-cause patient survival (p < 0.01, hazard ratio for mortality=2.52, 95% CI 2.38-2.67)., Conclusions: MMN was associated with Caucasian race, male gender, and older age, compared with other ESRD patients. Patients with MMN had evidence of poorer medical condition on initiation of dialysis compared to other patients. MMN was associated with decreased patient survival after initiation of dialysis, although better than in some previous reports, and patients with MMN may be initiated on dialysis at a lower level of renal function than other patients with ESRD.

Purpose: The national rate of and risk factors for bacterial endocarditis in renal transplant recipients has not been reported., Methods: Retrospective registry study of 33,479 renal transplant recipients in the United States Renal Data System (USRDS) between 1 July 1994 and 30 June 1997. Hospitalizations for a primary diagnosis of bacterial endocarditis (ICD-9 codes 421.x) within three years after renal transplant were assessed., Results: Renal transplant recipients had an unadjusted incidence ratio for endocarditis of 7.84 (95% confidence interval 4.72-13.25) in 1996. In multivariate analysis, a history of hospitalization for valvular heart disease (adjusted odds ratio (AOR), 25.81, 95% confidence interval 11.28-59.07), graft loss (AOR, 2.81, 95% CI 1.34-5.09), and increased duration of dialysis prior to transplantation were independently associated with hospitalizations for bacterial endocarditis after transplantation. Hospitalization for endocarditis was associated with increased patient mortality in Cox Regression analysis, hazard ratio 4.79, 95% CI 2.97-6.76., Conclusions: The overall incidence of bacterial endocarditis was much greater in renal transplant recipients than in the general population, although it is still relatively infrequent. Independent risk factors for bacterial endocarditis in the renal transplant recipients were identified, the most significant of which was valvular heart disease. Endocarditis substantially impacts renal transplant recipient survival.

Aims: Previous studies have identified risk factors for and mortality associated with hospitalized septicemia (septicemia) in patients with end-stage renal disease (ESRD). However, the etiologies of septicemia in this population have not been determined., Methods: 327,993 patients in the United States Renal Data System initiated on ESRD therapy between January 1, 1992, and June 30, 1997, who never received renal transplants were analyzed in a retrospective registry study of hospitalized cases of septicemia (ICD9 038.x)., Results: Of the study population, 43,441 (13.2%) had septicemia. In logistic regression analysis, septicemia was associated with female gender, African American race, ESRD due to diabetes and obstruction/chronic pyelonephritis, increased age, and hemodialysis (vs. peritoneal dialysis). Polycystic kidney disease and glomerulonephritis were associated with decreased risk of septicemia. At initiation of dialysis, higher hemoglobin, and lower weight, creatinine, and albumin were associated with septicemia. Among patients with septicemia, the leading specified etiologies were Staphylococcus (34%) and miscellaneous Gram-negative rods (21.7%). Etiologies of septicemia were significantly associated with hemodialysis (Gram-positives and Pneumococcus), female gender (Gram-negatives except Pseudomonas), African American race (Staphylococcus), and diabetes (global). Hemodialysis (vs. peritoneal dialysis) and Staphylococcus as an etiology of septicemia were associated with repeated hospitalizations for septicemia. Septicemia was independently associated with patient mortality, and African Americans and females with septicemia were at disproportionately greater risk of mortality., Conclusions: This study identifies significant associations between septicemia and female gender, African American race, hemodialysis, and higher hemoglobin. Significant associations between etiologies of septicemia and patient subgroups are also identified.

National statistics for patient characteristics and survival of renal transplant recipients positive for hepatitis C virus (HCV+) at the time of renal transplant are presented. A historical cohort analysis of 33479 renal transplant recipients in the United States Renal Data System from 1 July, 1994 to 30 June, 1997 has been carried out. The medical evidence form was also used for additional variables, but because of fewer available values, this was analyzed in a separate model. Outcomes were patient characteristics and survival associated with HCV+. Of 28692 recipients with valid HCV serologies, 1624 were HCV+ at transplant (5.7% prevalence). In logistic regression analysis, HCV+ was associated with African-American race, male gender, cadaveric donor type, increased duration of pre-transplant dialysis, previous transplant, donor HCV+, recipient (but not donor) age, serum albumin, alcohol use, and increased all-cause hospitalizations. Diabetes and IgA nephropathy were less associated with HCV+. Total all-cause, unadjusted mortality was 13.1% in HCV+ vs. 8.5% in HCV- patients (p <0.01 by log rank test). In Cox regression, mortality was higher for HCV+ (adjusted hazard ratio = 1.23, 95% confidence interval = 1.01-1.49, p = 0.04). HCV+ recipients were more likely to be African-American, male, older, and to have received repeat transplants and donor HCV+ transplants. HCV+ recipients also had substantially longer waiting times for transplant. In contrast to recent studies, diabetes did not have an increased association with HCV+, perhaps due to limitations of the database. HCV+ recipients had increased mortality and hospitalization rates compared with other transplant recipients.

Context: Incidence of end-stage renal disease due to hypertension has increased in recent decades, but the optimal strategy for treatment of hypertension to prevent renal failure is unknown, especially among African Americans., Objective: To compare the effects of an angiotensin-converting enzyme (ACE) inhibitor (ramipril), a dihydropyridine calcium channel blocker (amlodipine), and a beta-blocker (metoprolol) on hypertensive renal disease progression., Design, Setting, and Participants: Interim analysis of a randomized, double-blind, 3 x 2 factorial trial conducted in 1094 African Americans aged 18 to 70 years with hypertensive renal disease (glomerular filtration rate [GFR] of 20-65 mL/min per 1.73 m(2)) enrolled between February 1995 and September 1998. This report compares the ramipril and amlodipine groups following discontinuation of the amlodipine intervention in September 2000., Interventions: Participants were randomly assigned to receive amlodipine, 5 to 10 mg/d (n = 217), ramipril, 2.5 to 10 mg/d (n = 436), or metoprolol, 50 to 200 mg/d (n = 441), with other agents added to achieve 1 of 2 blood pressure goals., Main Outcome Measures: The primary outcome measure was the rate of change in GFR; the main secondary outcome was a composite index of the clinical end points of reduction in GFR of more than 50% or 25 mL/min per 1.73 m(2), end-stage renal disease, or death., Results: Among participants with a urinary protein to creatinine ratio of >0.22 (corresponding approximately to proteinuria of more than 300 mg/d), the ramipril group had a 36% (2.02 [SE, 0.74] mL/min per 1.73 m(2)/y) slower mean decline in GFR over 3 years (P =.006) and a 48% reduced risk of the clinical end points vs the amlodipine group (95% confidence interval [CI], 20%-66%). In the entire cohort, there was no significant difference in mean GFR decline from baseline to 3 years between treatment groups (P =.38). However, compared with the amlodipine group, after adjustment for baseline covariates the ramipril group had a 38% reduced risk of clinical end points (95% CI, 13%-56%), a 36% slower mean decline in GFR after 3 months (P =.002), and less proteinuria (P<.001)., Conclusion: Ramipril, compared with amlodipine, retards renal disease progression in patients with hypertensive renal disease and proteinuria and may offer benefit to patients without proteinuria.

Hemodialyzer reuse is commonly practiced in the United States. Recent studies have raised concerns about the mortality risk associated with certain reuse practices. We evaluated adjusted mortality risk during 1- to 2-year follow-up in a representative sample of 12,791 chronic hemodialysis patients treated in 1,394 dialysis facilities from 1994 through 1995. Medical record abstraction provided data on reuse practice, use of bleach, dialyzer membrane, dialysis dose, and patient characteristics and comorbidity. Mortality risk was analyzed by bootstrapped Cox models by (1) no reuse versus reuse, (2) reuse agent, and (3) dialyzer membrane with and without the use of bleach, while considering dialysis and patient factors. The relative risk (RR) for mortality did not differ for patients in reuse versus no-reuse units (RR = 0.96; 95% confidence interval [CI], 0.86 to 1.08; P > 0.50), and similar results were found with different levels of adjustment and subgroups (RR = 1.01 to 1.05; 95% CI, lower bound > 0.90, upper bound < 1.19 each; each P > 0.40). The RR for peracetic acid mixture versus formalin varied significantly by membrane type and use of bleach during reprocessing, achieving borderline significance for synthetic membranes. Among synthetic membranes, mortality was greater with low-flux than high-flux membranes (RR = 1.24; 95% CI, 1.02 to 1.52; P = 0.04) and without than with bleach during reprocessing (RR = 1.24; 95% CI, 1.01 to 1.48; P = 0.04). Among all membranes, mortality was lowest for patients treated with high-flux synthetic membranes (RR = 0.82; 95% CI, 0.72 to 0.93; P = 0.002). Although mortality was not greater in reuse than no-reuse units overall, differences may exist in mortality risk by reuse agent. Use of high-flux synthetic membrane dialyzers was associated with lower mortality risk, particularly when exposed to bleach. Clearance of larger molecules may have a role.

Rates of and risk factors for graft loss and graft loss resulting from recurrent focal segmental glomerulosclerosis (FSGS) have not been studied in a national population. A retrospective analysis was performed on a national registry (1999 United States Renal Data System) of 101,808 renal transplant recipients (October 1, 1987, to December 31, 1996). Of these, 3,861 recipients of solitary renal transplants who had end-stage renal disease resulting from FSGS met inclusion criteria. Outcomes were graft loss and graft loss resulting from recurrent FSGS. As a percentage of all graft loss, recurrent FSGS accounted for 18.7% in living donor recipients and 7.8% in cadaveric recipients. In white recipients, the corresponding figures were 27% and 13%. In multivariate analysis, factors associated with graft loss resulting from recurrent FSGS were white recipient, donor African-American kidney in white recipient, younger recipient age, and treatment for rejection. African-American recipients had higher rates of graft loss overall. A living donor was associated with superior overall graft survival. Among renal transplant recipients with FSGS, white recipients had a higher risk of graft loss resulting from recurrent FSGS, disproportionately seen in recipients of African-American kidneys. The role of donor/recipient race pairing on graft loss resulting from recurrent FSGS should be validated. Living donor had no association with graft loss from recurrent FSGS after correction for other factors. African-American recipients with FSGS may have the most to gain from a living donor, given their improved graft survival and decreased risk of graft loss resulting from recurrent FSGS. This is a US government work. There are no restrictions on its use.

Background: Lower serum albumin concentrations predict increased mortality in hemodialysis (HD) patients. Many demographic, comorbidity, and modifiable treatment-related factors that predict HD patient outcomes may be associated with serum albumin., Methods: Cross-sectional predictors of baseline albumin on December 31, 1993 were sought (N = 3981). Additional effects of the same baseline predictors on subsequent trends in albumin over one year were examined in a nested subsample of patients (N = 2245). Wave-1 of the United States Renal Data System Dialysis Morbidity and Mortality special study provided the data., Results: Significant associations (P < 0.05) are summarized as older age, female gender, peripheral vascular disease, chronic obstructive pulmonary disease, and cancer predicted a lower baseline albumin and negatively influenced subsequent albumin trends. Baseline albumin was higher for blacks (vs. whites), lower for smoking and diabetes, and lower during the first year of HD treatment (<3 months and 3 to 12 months, vs.> 1 year). Trend analysis showed more positive albumin slopes for patients in their first year on HD and more negative slopes for Native Americans (vs. whites). Baseline albumin was correlated with the type of vascular access being used [arteriovenous (AV) fistulas > AV grafts > permanent catheters > temporary catheters]. Trend analysis predicted more negative albumin slopes for AV grafts and permanent catheters (vs. AV fistula access). Baseline albumin correlated inversely with bicarbonate and directly with hematocrit. Dialysis with unmodified cellulose membranes, without reuse, predicted lower baseline albumin than the other membrane-reuse categories., Conclusions: Several exposures, which may be modifiable, were associated with serum albumin.

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 (P < 0.02) 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; P < 0. 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.

Hypertension (HTN) and diabetes mellitus (DM) predispose to systemic atherosclerosis with renal involvement. The prevalence of HTN and DM in cadaveric renal donors (affected donors) and the results of transplantation are unknown. We investigated these issues with national data from the US Renal Data System. A total of 4,035 transplants from affected donors were matched 1:1 with unaffected controls according to donor age and race, recipient race, and year of transplantation. Graft and patient survival were estimated. Among the 25,039 solitary renal transplantations performed between July 1, 1994, and June 30, 1997, cadaveric renal transplants from donors with HTN accounted for 15%, and donors with DM, 2%. Programs with 1-year cadaveric renal graft survival rates greater than 90% had 50% less affected donors compared with programs having 1-year cadaveric renal graft survival rates of 85% or less. Compared with donor-age-matched controls, transplants from affected donors were at minimally increased risk for primary nonfunction, delayed graft function, and acute rejection. Three-year graft survival rates were 71% in affected donor organs and 75% in controls (P = 0.001). Compared with controls, duration of HTN was an independent risk factor for graft survival (3-year graft survival rates, 75% versus 65%; relative risk = 1.36 for HTN >10 years; P < 0.001). A substantial fraction of cadaveric renal donors have preexisting HTN. Programs transplanting fewer affected donor kidneys had better than average results. Because the negative impact of donor HTN and DM on transplant outcome was of moderate degree except when the duration of donor HTN was greater than 10 years, use of affected donors should not be discouraged, but graft and patient survival analyses should account for their presence.

Background: Mycophenolate Mofetil (MMF) has been shown to significantly decrease the number of acute rejection episodes in renal transplant recipients during the 1st year. A beneficial effect of MMF on long-term graft survival has been more difficult to demonstrate. This beneficial effect has not been detected, despite the impact of acute rejection on the development of chronic allograft nephropathy and experimental evidence that MMF may have a salutary effect on chronic allograft nephropathy independent of that of rejection., Methods: Data on 66,774 renal transplant recipients from the U.S. renal transplant scientific registry were analyzed. Patients who received a solitary renal transplant between October 1, 1988 and June 30, 1997 were studied. The Cox proportional hazard regression was used to estimate relevant risk factors. Kaplan-Meier analysis was performed for censored graft survival., Results: MMF decreased the relative risk for development of chronic allograft failure (CAF) by 27% (risk ratio [RR] 0.73, P<0.001). This effect was independent of its outcome on acute rejection. Censored graft survival using MMF versus azathioprine was significantly improved by Kaplan-Meier analysis at 4 years (85.61% v. 81.9%). The effect of an acute rejection episode on the risk of developing CAF seems to be increasing over time (RR=1.9, 1988-91; RR=2.9, 1992-94; RR=3.7, 1995-97)., Conclusion: MMF therapy decreases the risk of developing CAF. This improvement is only partly caused by the decrease in the incidence of acute rejection observed with MMF; but, is also caused by an effect independent of acute rejection.

Unlabelled: Long-term survival in renal transplant recipients with graft function., Background: Death with graft function (DWGF) is a common cause of graft loss. The risks and determinants of DWGF have not been studied in a recent cohort of renal transplant recipients. We performed a population-based survival analysis of U.S. patients with end-stage renal disease (ESRD) transplanted between 1988 and 1997., Methods: Registry data were used to evaluate long-term patient survival and cause-specific risks of DWGF in 86,502 adult (>/=18 years) renal transplant recipients., Results: Out of 18,482 deaths, 38% (N = 7040) were deaths with graft function. This accounts for 42. 5% of all graft loss. Patient survival with graft function was 97, 91, and 86% at 1, 5, and 10 years, respectively. The risk of DWGF decreased by 67% (RR = 0.33, P < 0.001) between 1988 and 1997. The adjusted rate of DWGF was 4.6, 0.8, 2.2, and 1.4 deaths per 1000 person-years for cardiovascular disease, stroke, infections, and malignancy, respectively. The suicide rate was 15.7 versus 9.0 deaths per 100,000 person-years in the general population (P < 0. 001). In multivariate analysis, the following factors were independently and significantly predictive of DWGF: white recipient, age at transplantation, ESRD caused by hypertension or diabetes mellitus, length of pretransplant dialysis, delayed graft function, acute rejection, panel reactive antibody> 30%, African American donor race, age> 45 years, and donor death caused by cerebrovascular disease., Conclusions: Patients with graft function have a high long-term survival. Although DWGF is a major cause of graft loss, the risk has declined substantially since 1990. Cardiovascular disease was the predominant reported cause of DWGF. Other causes vary by post-transplant time period. Attention to atherosclerotic risk factors may be the most important challenge to further improve the longevity of patients with successful renal transplants.

This study investigates the role of body size on the mortality risk associated with dialysis dose in chronic hemodialysis patients. A national US random sample from the US Renal Data System was used for this observational longitudinal study of 2-year mortality. Prevalent hemodialysis patients treated between 1990 and 1995 were included (n = 9,165). A Cox proportional hazards model, adjusting for patient characteristics, was used to calculate the relative risk (RR) for mortality. Both dialysis dose (equilibrated Kt/V [eKt/V]) and body size (body weight, body volume, and body mass index) were independently and significantly (P < 0.01 for each measure) inversely related to mortality when adjusted for age and diabetes. Mortality was less among larger patients and those receiving greater eKt/V. The overall association of mortality risk with eKt/V was negative and significant in all patient subgroups defined by body size and by race-sex categories in the range 0.6 < eKt/V < 1.6. The association was negative in the restricted range 0.9 < eKt/V < 1.6 (although not generally significant) for all body-size subgroups and for three of four race-by-sex subgroups, excepting black men (RR = 1. 003/0.1 eKt/V; P > 0.95). These findings suggest that dose of dialysis and several measures of body size are important and independent correlates of mortality. These results suggest that patient management protocols should attempt to ensure both good patient nutrition and adequate dose of dialysis, in addition to managing coexisting medical conditions.

Background and Methods: The extent to which renal allotransplantation - as compared with long-term dialysis - improves survival among patients with end-stage renal disease is controversial, because those selected for transplantation may have a lower base-line risk of death. 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., Results: Among the various subgroups, the standardized mortality ratio for the patients on dialysis who were awaiting transplantation (annual death rate, 6.3 per 100 patient-years) was 38 to 58 percent lower than that for all patients on dialysis (annual death rate, 16.1 per 100 patient-years). The relative risk of death during the first 2 weeks after transplantation was 2.8 times as high as that for patients on dialysis who had equal lengths of follow-up since placement on the waiting list, but at 18 months the risk was much lower (relative risk, 0.32; 95 percent confidence interval, 0.30 to 0.35; P<0.001). The likelihood of survival became equal in the two groups within 5 to 673 days after transplantation in all the subgroups of patients we examined. The long-term mortality rate was 48 to 82 percent lower among transplant recipients (annual death rate, 3.8 per 100 patient-years) than patients on the waiting list, with relatively larger benefits among patients who were 20 to 39 years old, white patients, and younger patients with diabetes., Conclusions: Among patients with end-stage renal disease, healthier patients are placed on the waiting list for transplantation, and long-term survival is better among those on the waiting list who eventually undergo transplantation.

Unlabelled: Survival advantage in Asian American end-stage renal disease patients., Background: An earlier study documented a lower mortality risk for end-stage renal disease (ESRD) patients in Japan compared with the United States. We compared the mortality of Caucasian (white) and Asian American dialysis patients in the United States to evaluate whether Asian ancestry was associated with lower mortality in the United States., Methods: The study sample from the U.S. Renal Data System census of ESRD patients treated in the United States included 84,192 white or Asian patients starting dialysis during May 1995 to April 1997, of whom 18,435 died by April 30, 1997. Patient characteristics were described by race. Relative mortality risks (RRs) for Asian Americans relative to whites were analyzed by Cox proportional hazards regression models adjusting for characteristics and comorbidities. Population death rates were derived from vital statistics for the United States and Japan by age and sex., Results: Adjusting for demographics, diabetes, comorbidities, and nutritional factors, the RR for Asian Americans was 0.75 (P = 0.0001). Race-specific background population death rates accounted for over half of the race-related mortality difference. For whites, mortality decreased as the body mass index (BMI) increased. For Asians, the relationship between BMI and survival was u-shaped. The ratio of Asian American/white dialysis death rates and the ratio of Asian American/white general population death rates both varied by age in a similar pattern. The population death rates of Asian American and Japanese were also similar., Conclusion: Among dialysis patients, Asian Americans had a markedly lower adjusted RR than whites. The effect of BMI on survival differed by race. Compared with the respective general population, dialysis patients had the same relative increase in death rates for both races. The difference in death rates between the United States and Japan does not appear to be primarily treatment related, but rather is related to background death rates.

Background: Renal vascular thrombosis (RVT) is a rare but catastrophic complication of renal transplantation. Although a plethora of risk factors has been identified, a large proportion of cases of RVT is unexplained. Uremic coagulopathy and dialysis modality may predispose to RVT. We investigated the impact of the pretransplant dialysis modality on the risk of RVT in adult renal transplant recipients., Methods: Renal transplant recipients (age 18 years or more) who were enrolled in the national registry between 1990 and 1996 (N = 84,513) were evaluated for RVT occurring within 30 days of transplantation. Each case was matched with two controls from the same transplant center and with the year of transplantation. The association between RVT and 18 factors was studied with multivariate conditional logistic regression., Results: Forty-nine percent of all cases of RVT (365 out of 743) occurred in repeat transplant recipients with an adjusted odds ratio (OR) of 5.72 compared with first transplants (P < 0.001). There were a significantly higher odds of RVT in peritoneal dialysis (PD)-compared with hemodialysis (HD)-treated patients (OR = 1.87, P = 0.001). Change in dialysis modality was an independent predictor of RVT: switching from HD to PD (OR = 3.59, P < 0.001) and from PD to HD (OR = 1.62, P = 0.047). Compared with primary transplant recipients on HD (OR = 1.00), the highest odds of RVT were in repeat transplant recipients treated with PD (OR = 12.95, P < 0.001) and HD (OR = 4.50, P < 0.001). Other independent predictors of RVT were preemptive transplantation, relatively young and old donor age, diabetes mellitus and systemic lupus erythematosus as causes of end-stage renal disease, recipient gender, and lower panel reactive antibody levels (PRAs)., Conclusions: The strongest risk factors for RVT were retransplantation and prior PD treatment. Prevention of RVT with perioperative anticoagulation should be studied in patients who have a constellation of the identified risk factors.

The role of predialysis blood pressure (BP) as a risk factor for the high mortality in chronic hemodialysis (HD) patients has remained controversial. The objective of the current study was to further explore in a national random sample of 4,499 US hemodialysis patients any relationship of systolic or diastolic and predialysis or postdialysis BP with mortality, while considering subgroups of patients and controlling for other patient characteristics and comorbidities. The main finding of this study is the association of a low predialysis systolic BP with an elevated adjusted mortality risk (relative mortality risk [RR] = 1.86 for systolic BP < 110, P < 0.0001). No association with an elevated mortality risk could be observed for predialysis systolic hypertension (RR = 0.98 to 0.99, not significant [NS]), except for an elevated risk of cerebrovascular deaths. Postdialysis systolic BP was associated with an elevated mortality risk both for low and high BP levels as compared with midrange BP. Further evaluation of the elevated mortality risk associated with low predialysis systolic BP indicated similar patterns for both diabetic and nondiabetic subgroups and for patients with and without congestive heart failure (CHF) or coronary artery disease, although it was more pronounced among those with CHF. The level of predialysis fluid excess did not modify these results substantially. The findings from this historical prospective national study do not argue against the treatment of hypertension and suggest greater attention to postdialysis hypertension. The strikingly elevated mortality risk with low predialysis systolic BP suggests that low predialysis BP needs to be viewed with great concern and avoided where possible.

The type of dialysis membrane used for routine therapy has been recently shown to correlate with the survival of chronic hemodialysis patients. We examined whether this effect of dialysis membrane could be explained by differences in dialyzer removal of middle molecules using data from the 1991 Case Mix Adequacy Study of the United States Renal Data System. The sample analyzed included patients who had been treated by hemodialysis for 1 year or more, who were dialyzed with the 19 most commonly used dialyzers in 1991, and for whom delivered urea Kt/V could be calculated from predialysis and postdialysis blood urea nitrogen concentrations. Vitamin B12 (1,355 daltons) was used as a marker for middle molecules, and the clearance of vitamin B12 was estimated based on in vitro data. After adjustments for case mix, comorbidities, and urea Kt/V, the relative risk of mortality for a 10% higher calculated total cleared volume of vitamin B12 was 0.953 (P < 0.0001 v 1.000). Similar results were obtained when middle molecule removal was adjusted for body size. We conclude that both small and middle molecule removal indices appear to be independently associated with the risk of mortality in chronic hemodialysis patients. Differences in mortality when using different types of dialysis membrane may be explained by differences in middle molecule removal.

Background: The role of renal transplantation as treatment for end-stage sickle cell nephropathy (SCN) has not been well established., Methods: We performed a comparative investigation of patient and allograft outcomes among age-matched African-American kidney transplant recipients with ESRD as a result of SCN (n=82) and all other causes (Other-ESRD, n=22,565)., Results: The incidence of delayed graft function and predischarge acute rejection in SCN group (24% and 26%) was similar to that observed in the Other-ESRD group (29% and 27%). The mean discharge serum creatinine (SCr) was 2.7 (+/-2.5) mg/dl in the SCN recipients compared to 3.0 (+/-2.5) mg/dl in the Other-ESRD recipients (P=0.42). There was no difference in the 1-year cadaveric graft survival (SCN: 78% vs. Other-ESRD: 77%), and the multivariable adjusted 1-year risk of graft loss indicated no significant effect of SCN (relative risk [RR]=1.39, P=0.149). However, the 3-year cadaveric graft survival tended to be lower in the SCN group (48% vs. 60%, P=0.055) and their adjusted 3-year risk of graft loss was significantly greater (RR= 1.60, P=0.003). There was a trend toward improved survival in the SCN transplant recipients compared to their dialysis-treated, wait-listed counterparts (RR=0.14, P=0.056). In comparison to the Other-ESRD (RR=1.00), the adjusted mortality risk in the SCN group was higher both at 1 year (RR=2.95, P=0.001) and at 3 years (RR=2.82, P=0.0001) after renal transplantation., Conclusions: The short-term renal allograft result in recipients with end-stage SCN was similar to that obtained in other causes of ESRD, but the long-term outcome was comparatively diminished. There was a trend toward better patient survival with renal transplantation relative to dialysis in end-stage SCN.

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.

Although dialyzer reuse in chronic hemodialysis patients is commonly practiced in the United States, performance of reused dialyzers has not been extensively and critically evaluated. The present study analyzes data extracted from a multicenter clinical trial (the HEMO Study) and examines the effect of reuse on urea and beta2-microglobulin (beta2M) clearance by low-flux and high-flux dialyzers reprocessed with various germicides. The dialyzers evaluated contained either modified cellulosic or polysulfone membranes, whereas the germicides examined included peroxyacetic acid/acetic acid/hydrogen peroxide combination (Renalin), bleach in conjunction with formaldehyde, glutaraldehyde or Renalin, and heated citric acid. Clearance of beta2M decreased, remained unchanged, or increased substantially with reuse, depending on both the membrane material and the reprocessing technique. In contrast, urea clearance decreased only slightly (approximately 1 to 2% per 10 reuses), albeit statistically significantly with reuse, regardless of the porosity of the membrane and reprocessing method. Inasmuch as patient survival in the chronic hemodialysis population is influenced by clearances of small solutes and middle molecules, precise knowledge of the membrane material and reprocessing technique is important for the prescription of hemodialysis in centers practicing reuse.