While Blacks have a shorter average lifespan than Whites in the general US population, some studies indicate that among kidney failure patients on dialysis, Blacks tend to live longer than whites.
To investigate the issue further, Guofen Yan, PhD (University of Virginia School of Medicine) and her colleagues studied data from the United States Renal Data System pertaining to 1,282,201 adults undergoing dialysis between 1995 and 2009.
The researchers found that Hispanics were the least likely to die and non-Hispanic Whites were most likely to die over an average follow-up of 22.3 months. Blacks risk of dying was in between these two racial/ethnic groups. This pattern held true in all age groups, except for the youngest (18 to 30 years old), where there was a higher risk of dying for Blacks compared with non-Hispanic Whites.
"The survival advantage of racial/ethnic minorities on maintenance dialysis is one of the unresolved issues that has been around for some time and is of interest to health care providers, patients, and public policy," said Dr. Yan. She noted that several hypotheses exist to explain why Black and Hispanic dialysis patients tend to live longer than Whites in most age groups. It may be that Black and Hispanic patients with kidney disease are more likely to die before they develop kidney failure, and those surviving are generally healthier and hence more likely to live longer with kidney failure than Whites.
"Examining dialysis survival among racial and ethnic subgroups may help identify care disparities and outcome differences in chronic kidney disease. Continued effort to discern the factors responsible for the general survival advantage of Black and Hispanic dialysis patients may yield major clinical and public health implications for the kidney failure and kidney disease populations," said Dr. Yan.