Conventional wisdom among kidney specialists has been that African Americans do better on dialysis than their white counterparts — leading doctors to advise black patients to stick with dialysis rather than pursue kidney transplantation. A surprising new study has found exactly the opposite is true.

Researchers looked at the medical records of more than a million patients with advanced kidney disease, breaking down the data by race as well as age, and they were surprised to find that black dialysis patients under age 50 are actually twice as likely to die than their white counterparts.

Dr. Dorry Segev, who led the study at Johns Hopkins University School of Medicine explained that previous studies had masked the differences between young and old people. “If you are African American and young and on dialysis you need to pursue kidney transplantation, advises Segev. “You need to look for a living donor, you need to pursue getting on a waiting list.”

Doctors aren’t sure why young African American dialysis patients have such a marked mortality risk, but a lack of access to medical care due to economic factors is suspected. According to researchers, all African American dialysis patients under the age of 50 in the U.S. should be impacted by the findings of this new study.