Sickle cell nephropathy at end-stage renal disease in the United States: patient characteristics and survival

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.