Racial differences in the incidence of end-stage renal disease.

OBJECTIVE

To examine trends in the incidence of treated end-stage renal disease (ESRD) and variations between blacks and whites.

DESIGN

Retrospective record reviews of all new patients > or = 15 years starting chronic dialysis during 1980-1988 at the Piedmont Dialysis Center, Forsyth County, North Carolina.

RESULTS

The cumulative nine-year incidence rate for hypertensive ESRD was 570 per million, and for diabetic ESRD 497 per million. Among men, hypertensive ESRD accounted for the largest proportion of cases (39.2% and 28.4%, blacks and whites respectively), while diabetic ESRD contributed 33.9% of black female cases and 24.4% of white female cases. Compared to whites, blacks were at significantly increased risk, with an adjusted risk odds ratio (OR) of 4.4 (95% confidence interval (CI) 3.5-6.0) for all causes combined, 6.0 (CI 3.9-9.0) for hypertensive renal disease, 6.0 (CI 3.8-9.3) for renal disease due to insulin-dependent diabetes mellitus, and 12.2 (CI 6.9-21.7) due to non-insulin dependent diabetes mellitus (NIDDM). The greatest risk among blacks was seen in the 55-64 year age group, with ORs of 9.1 for all causes combined and 30.6 for hypertensive renal disease. The OR for renal disease due to NIDDM for black versus white women was 20.0 (CI 9.5-41.7). Compared to 1980, 1981, 1982 and 1983, increased incidence rates were seen in each year after 1984.

CONCLUSION

These findings show even greater excess risk of ESRD among blacks than previously reported. The majority of the excess risk is seen for ESRD due to hypertension and diabetes, especially NIDDM. The reasons for the increased risk among blacks, and for the increasing incidence rates of ESRD are not known.