White/black racial differences in risk of end-stage renal disease and death.

Background: End-stage renal disease disproportionately affects black persons, but it is unknown when in the course of chronic kidney disease racial differences arise. Understanding the natural history of racial differences in kidney disease may help guide efforts to reduce disparities.
Methods: We compared white/black differences in the risk of end-stage renal disease and death by level of estimated glomerular filtration rate (eGFR) at baseline in a national sample of 2,015,891 veterans between 2001 and 2005.
Results: Rates of end-stage renal disease among black patients exceeded those among white patients at all levels of baseline eGFR. The adjusted hazard ratios for end-stage renal disease associated with black versus white race for patients with an eGFR > or = 90, 60-89, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m2, respectively, were 2.14 (95% confidence interval [CI], 1.72-2.65), 2.30 (95% CI, 2.02-2.61), 3.08 (95% CI, 2.74-3.46), 2.47 (95% CI, 2.26-2.70), 1.86 (95% CI, 1.75-1.98), and 1.23 (95% CI, 1.12-1.34). We observed a similar pattern for mortality, with equal or higher rates of death among black persons at all levels of eGFR. The highest risk of mortality associated with black race also was observed among those with an eGFR 45-59 mL/min/1.73 m2 (hazard ratio 1.32, 95% CI, 1.27-1.36).
Conclusion: Racial differences in the risk of end-stage renal disease appear early in the course of kidney disease and are not explained by a survival advantage among blacks. Efforts to identify and slow progression of chronic kidney disease at earlier stages may be needed to reduce racial disparities.