Survival benefit of recombinant human erythropoietin administration prior to onset of end-stage renal disease: variations across surrogates for quality of care and time.

BACKGROUND: Recombinant human erythropoietin (rHuEPO) is recommended pre-dialysis to correct the anemia of chronic kidney disease. This study evaluated the impact of pre-dialysis rHuEPO on mortality in incident end-stage renal disease (ESRD) patients with varying levels of pre-ESRD care. METHODS: The study included 15,807 individuals whose exposure to rHuEPO was determined from HCFA 2728 forms. RESULTS: Median follow-up after starting dialysis was 32.8 months. Pre-ESRD rHuEPO use occurred in only 3,994 (25.3%) subjects and was more common in individuals with insurance, currently employed, started on outpatient dialysis, and initiated on peritoneal dialysis. During the study, 8,608 (54.5%) patients died. The risk of death was lower for rHuEPO-treated patients versus non-treated (relative risk 0.87, 95% CI 0.82-0.92). The survival benefit with rHuEPO was greatest early after dialysis initiation (relative risk at 1 vs. 7 years post-dialysis 0.73, 95% CI 0.66-0.80 vs. 0.87, 95% CI 0.82-0.92, respectively), did not vary across several surrogates for quality of care, and was greatest in those with the highest achieved hematocrit pre-ESRD. CONCLUSION: Pre-dialysis rHuEPO confers a survival benefit that depends on achieved hematocrit and diminishes post-dialysis, but is independent of several surrogates for quality of care except for insurance status pre-ESRD.

Retransplantation in patients with graft loss caused by polyoma virus nephropathy.

The characteristics and outcome in 10 patients who underwent retransplantation after losing their renal grafts to BK virus-associated nephropathy (BKAN) are described. The patients underwent retransplantation at a mean of 13.3 months after failure of the first graft. Nephroureterectomy of the first graft was performed in seven patients. Maintenance immunosuppression regimens after the first and second grafts were similar, consisting of a combination of a calcineurin inhibitor, mycophenolate mofetil, and prednisone. BKAN recurred in one patient 8 months after retransplantation, but stabilization of graft function was achieved with a decrease in immunosuppression and treatment with low-dose cidofovir. After a mean follow-up of 34.6 months, all patients were found to have good graft function with a mean creatinine of 1.5 mg/dL. From this collective experience from five transplant centers (although the follow-up after retransplantation was not extensive), it can be concluded that patients with graft loss caused by BKAN can safely undergo retransplantation. The risk of recurrence does not seem to be increased in comparison with the first graft.

RAAS escape: a real clinical entity that may be important in the progression of cardiovascular and renal disease.

Interruption of the renin-angiotensin-aldosterone system (RAAS) at different levels is target-organ protective in several disease states; however, complete blockade is unlikely to be achieved due to escape mechanisms whenever blockade is attempted, incomplete knowledge of the role of all elements of the RAAS, and lack of pharmacotherapy against some elements that have been shown to contribute to disease states. Aldosterone has been overlooked as a mediator of RAAS escape and a key factor in target-organ injury despite the use of available RAAS blockers. Aldosterone is thought to play a role in the development of hypertension, alteration in vascular structure, vascular smooth muscle hypertrophy, endothelial dysfunction, structural renal injury, proteinuria, left ventricular remodeling, collagen synthesis, and myocardial fibrosis. Aldosterone receptor antagonists have been shown to antagonize all these effects in experimental models. Clinical trials with aldosterone antagonists showed an improvement in survival and left ventricular mass index in patients with congestive heart failure, and a reduction in urinary protein excretion and left ventricular mass index in patients with type 2 diabetes and early nephropathy who developed aldosterone synthesis escape. Consequently, aldosterone receptor antagonists may have specific benefits for reducing target-organ injury, particularly if there is evidence of RAAS escape.

Optimizing target-organ protection in patients with diabetes mellitus: angiotensin-converting enzyme inhibitors or angiotensin receptor blockers?

High blood pressure in the setting of type 1 and type 2 diabetes is commonly associated with the earlier development of target-organ damage, including cardiovascular and cerebrovascular disease and progressive renal insufficiency. The major goal of treating high blood pressure in this population is to prevent or reduce the likelihood of target-organ damage. The treatment goal for high blood pressure, therefore, has to be defined based on optimal means of preventing cardiovascular and renal events. The reduction of high blood pressure with pharmacologic therapy is associated with reduction of cardiovascular events, renal disease, and associated mortality. However, many questions remain. Some of the basic and important questions include the following: What should be the goal of treated blood pressure in the diabetic, and are there preferred agents that should be used in the hypertensive diabetic population? How do angiotensin-converting enzyme inhibitors and angiotensin receptor blockers fit in? Are there advantages of one class over the other? The goal of this review is to summarize the recent clinical trial findings and try to provide recommendations based on the evidence of these trials to help the clinician better choose blood pressure goals and treatment strategies in the diabetic population.