Survival difference are not black and white

In the general population, African Americans die at earlier ages than whites, but among patients on dialysis, African Americans live longer than whites. A new study helps explain this paradox and could help prolong the lives of all patients on dialysis. The study appears in the Journal of the American Society Nephrology (JASN), a publication of the American Society of Nephrology.

High levels of inflammation—which may be due to conditions such as infections, inflammatory illnesses, periodontal disease, chronic lung disease, and obesity—increase dialysis patients' risk of dying prematurely. Deidra Crews, MD (Johns Hopkins University) and her colleagues wondered whether racial differences in inflammation might explain the survival paradox among dialysis patients.

The investigators followed 554 white and 262 African American dialysis patients from 81 clinics for an average of three years (range four months to 9.5 years). Among the major findings:

• At five years, a lower percentage of African Americans (34%) died compared with whites (56%), as expected.
• A survival advantage for African Americans only existed among patients with high levels of inflammation.
• When comparing patients with lower levels of inflammation, African American and white patients survived for similar lengths of time.

"Our findings challenge the long held notion that African Americans do better than whites on dialysis. If we can determine, and somehow modify the impact of inflammation, we may be able to improve survival for all patients treated with dialysis," said Dr. Crews.