Showing papers by "Lawrence Y. Agodoa published in 1999"

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

Abstract: Background 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. Methods In an attempt to distinguish the effects of patient selection from those of transplantation itself, we conducted a longitudinal study of mortality in 228,552 patients who were receiving long-term dialysis for end-stage renal disease. Of these patients, 46,164 were placed on a waiting list for transplantation, 23,275 of whom received a first cadaveric transplant between 1991 and 1997. The relative risk of death and survival were assessed with time-dependent nonproportional-hazards analysis, with adjustment for age, race, sex, cause of end-stage renal disease, geographic region, time from first treatment for end-stage renal disease to placement on the waiting list, and year of initial placement on the list. Results Among the various subgroups...

Effects of Hemodialyzer Reuse on Clearances of Urea and β2-Microglobulin

Abstract: Although dialyzer reuse in chronic hemodialysis pa- tients 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 b2-microglobulin (b2M) 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 per- oxide combination (Renalin ® ), bleach in conjunction with formaldehyde, glutaraldehyde or Renalin, and heated citric acid. Clearance of b2M 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 hemodi- alysis population is influenced by clearances of small solutes and middle molecules, precise knowledge of the membrane material and reprocessing technique is important for the pre- scription of hemodialysis in centers practicing reuse. High-flux hemodialyzers and reuse of dialyzers have been widely used for decades, yet the effects of these practices on solute clearances have not been fully evaluated. Although the beneficial effect of increasing urea clearance on clinical outcome has been established, at least up to a single-pool Kt/V value of 1.2 (1), there are also accumulating data suggesting that the removal of middle molecules (using vitamin B12 as marker) influences patient survival (2,3). Thus, maintenance of the clearance of both small and large solutes for reused dialyzers is important. Reuse can affect dialyzer performance in at least two different ways. The first is the result of deposition of blood elements inside the lumen of the blood compartment and onto the dialyzer mem- brane. The second is the result of the reprocessing procedure. At present, the popular germicides used in reprocessing in the United States are Renalin (made up of peroxyacetic acid, acetic acid, and hydrogen peroxide, Minntech, Minneapolis, MN), formaldehyde, and glutaraldehyde (4). To enhance the aesthetic appearance of the dialyzers during reuse, sodium hypochlorite (bleach) is often used in conjunction with formaldehyde or glutaraldehyde to re- move residual blood proteins. More recently, heated citric acid has also been introduced to clean and disinfect dialyzers for reuse. Because the chemical composition and mechanical structure are vastly different among various types of dialysis membranes, their interactions with the blood elements and reprocessing agents are likely to differ as well. The HEMO Study is a prospective randomized multicenter trial sponsored by the U.S. National Institutes of Health designed to examine the effects of urea Kt/V and the type of dialysis mem- brane on clinical outcome of chronic hemodialysis patients (5). Various models of dialyzers and reprocessing methods are used among the 15 clinical centers (more than 45 dialysis units) in the trial. Using this large database, we have prospectively examined the effects of various combinations of dialyzers and reprocessing agents on the clearance of urea and b2-microglobulin (b2M). The data show that the effects of reuse on b2M are far more drastic than those on urea clearance. Furthermore, the effects vary greatly depending on the dialysis membrane material and reprocessing reagents. These observations confirm and extend our fundamental understanding of alterations in dialyzer performance during reuse.

Prescription of twice-weekly hemodialysis in the USA.

Abstract: Background/Aims: The purpose of this study was to investigate the frequency and characteristics of two hemodialysis sessions/week, to identify factors which influence or predict thi

Renal transplantation in end-stage sickle cell nephropathy.

Abstract: 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.

Current strategies for management of hypertensive renal disease

Abstract: The incidence of hypertensive end-stage renal disease continues to increase annually To reduce this incidence, it is necessary to control systolic and diastolic hypertension Reversible causes should always be sought in any hypertensive patient who develops renal insufficiency Blood pressure should be reduced to 130/85 mm Hg, and in African Americans with hypertensive renal failure, reducing the blood pressure to 120/75 mm Hg may be beneficial Any antihypertensive treatment regimen that effectively lowers blood pressure will help slow progressive renal failure Whenever possible, an angiotensin-converting enzyme inhibitor should be part of the treatment, since these drugs have been shown to be renoprotective beyond their antihypertensive effect in certain renal disease categories