Race-dependent survival disparity on hemodialysis: Any role for high serum aluminum levels in higher Caucasian mortality?

The mortality rate on hemodialysis remains unacceptably high, and it is worse in Caucasian than in Afro-Americans. Defining factors that influence the survival disparity may help to develop strategy to improve survival for dialysis population at large. We compared one-year survival of 145 Caucasian with age and sex matched 685 Afro-American patients on hemodialysis. The predictive variables for survival in Caucasians and Afro-Americans were determined separately by Univariate Cox proportional hazard analysis, and variables that were significant were further analyzed using the multivariate format. By actuarial analysis, one-year survival was significantly higher in Afro-Americans than in Caucasians (p<0.001). In univariate analysis, serum albumin, pre-albumin and creatinine had positive influence, whereas age and diabetes had negative influence on both Caucasians' and Afro-Americans' survival. In Caucasians, unlike the Afro-Americans, male gender, underweight, and serum aluminum levels had significant negative influence on survival. Serum aluminum levels were higher in Caucasians compared to Afro-Americans (14.3±0.6 vs. 20±2.3 mcg/ml; m±SE, p=0.0009), and the slight but significant negative impact of serum aluminum on survival (RR 1.012, 1.003-1.021% CI, p<0.007) persisted in multivariate analysis after adjustment for age, gender, albumin, creatinine and BMI. Our data suggest that higher death rate in Caucasian compared to Afro-Americans is associated with higher prevalence of underweight and higher levels of serum aluminum. Further studies are required to verify the significance of our cross-sectional findings.