Incidence of atherosclerosis by race in the dialysis morbidity and mortality study: a sample of the US ESRD population.

Abstract

White individuals who are on dialysis experience much higher overall and cardiovascular mortality rates than black individuals despite a more favorable risk factor profile, but the incidence of nonfatal cardiovascular disease (CVD) to this racial disparity has not been well studied. A longitudinal study of 16,103 people who had ESRD and were enrolled in the United Renal Data System from 1993 to 1996 was conducted. The incidence of new and recurrent atherosclerotic CVD (ASCVD) events was determined using Medicare claims for hospitalizations and mortality among blacks and whites, stratified by ASCVD at baseline. ASCVD was defined as coronary heart disease, peripheral vascular disease, and cerebrovascular disease. Incidence of new ASCVD in people without ASCVD at baseline was 146.9 per 1000 person-years in whites and 118.7 per 1000 person-years in blacks. Incidence of recurrent ASCVD was 404.1 per 1000 person-years in whites and 317.5 per 1000 person-years in blacks. Whites were 1.35 (95% confidence interval, 1.18 to 1.55) times more likely to develop incident ASCVD compared with blacks and 1.25 (95% confidence interval, 1.14 to 1.36) times more likely to develop recurrent disease after adjusting for traditional CVD and dialysis-related risk factors. Excess risk for recurrent ASCVD in whites compared with blacks was consistently present no matter the duration of dialysis: Hazard ratio 1.42 for 0 to 6 mo and 1.40 for 6 to 12 mo. Whites who are treated with dialysis have a higher incidence of ASCVD than blacks who are on dialysis, both new and recurrent. Although differences in survival before the initiation of dialysis may contribute to the observed difference in ASCVD risk, it is not explained by baseline traditional and dialysis-related ASCVD risk factors.