Race and Mortality in Hemodialysis Patients in BrazilPlain-Language Summary

Rationale & Objective: Studies in the United States and United Kingdom generally report better survival for Black than White patients undergoing maintenance hemodialysis, a finding not explained by differences in sociodemographics or comorbid conditions. It is not clear if such findings can be generalized to other countries. We investigated the association between race and mortality among a Black, White, and Mixed-Race sample of maintenance hemodialysis patients in Salvador, Brazil. Study Design: Prospective cohort study. Baseline data collection from July 1, 2005 through December 31, 2010. The follow-up period ended on December 31, 2017. Setting & Participants: The Prospective Study of the Prognosis of Chronic Hemodialysis Patients (PROHEMO) is a cohort of 1,501 patients from 4 dialysis units in Salvador, Brazil. Predictor: Race categorized as White (12.9%), Mixed-Race (62.4%), and Black (24.8%), using White as the reference category. Outcome: Survival. Analytical Approach: Using Cox regression models, we tested the association between race and mortality, with adjustments for age, sex, social factors, laboratory results, and comorbid conditions. Results: The mean age was 49 years for Black and Mixed-Race patients and 55 years for White patients. In a Cox model adjusted for age, mortality did not differ between Black and White patients (HR, 1.10; 95% CI, 0.66-1.83) or between Mixed-Race and White patients (HR, 1.00; 95% CI, 0.65-1.54). Adjustment for sociodemographics and comorbid conditions had minimal impact on these results. Limitations: Potential residual confounding and lack of adjustment for time-varying variables. Conclusions: Contrary to studies in the United States and United Kingdom, we did not find racial difference in mortality among patients in our Brazilian setting who were being treated by maintenance hemodialysis. These results underscore the importance of investigating racial differences in mortality among patients undergoing maintenance hemodialysis in different populations and countries.