Race Gap in Kidney Transplant Outcomes Narrows Dramatically
At the end of a 20-year study period, the 1- and 3-year risk of graft loss did not differs significantly between black and white recipients.
PHILADELPHIA—Racial disparities in kidney transplant outcomes have improved dramatically in the United States, with white and black kidney recipients now experiencing similar 1- and 3-year risks of graft loss, researchers concluded from a study presented at the 2015 American Transplant Congress.
Tanjala Purnell, PhD, MPH, of Johns Hopkins University School of Medicine in Baltimore, and colleagues examined 22-year trends in kidney transplant outcomes using data from the Scientific Registry of Transplant Recipients. The study population included 145,489 white and 63,910 black adults who received a first-time living donor kidney transplant (LDKT) or deceased-donor kidney transplant (DDKT) from January 1, 1990 to December 31, 2012.
Results showed that black recipients experienced greater improvement in 5-year graft loss rates after LDKT and DDKT (15.2% and 20.8%, respectively) compared with whites (6.9% and 12.3%, respectively). In addition, blacks who received a DDKT during 1990–1992 were 39% more likely than whites to experience 5-year graft loss, whereas blacks who received a DDKT during 2007–2008 were only 10% more likely to experience 5-year graft loss than whites, in adjusted analyses.
Blacks who received a LDKT during 1990–1992 were 52% more likely than whites to experience 5-year graft loss, but this disparity fell to 38% during 2007–2008.
By the end of the study period, the researchers observed no statistically significant racial differences in 1- or 3-year graft loss after LDKT or DDKT.
In an interview with Renal & Urology News, Dr. Purnell explained that the improvement in racial disparity in graft loss may be attributable, at least in part, to a change in United Network for Organ Sharing (UNOS) policy in 2003 that eliminated priority points for HLA-B matching to address racial disparities in kidney transplant rates. A previous study led by Dorry L. Segev, MD, PhD, of Johns Hopkins, which was published in the American Journal of Kidney Diseases (2011;58:813-816), found a significant 23% reduction in the disparity in DDKT rates between blacks and whites after the UNOS policy change.
“It [the policy change] actually reduced the amount of time that patients were spending on dialysis,” Dr. Purnell said, noting that shorter dialysis vintage has been associated in prior studies with better kidney transplant outcomes.
In addition, during the study period, Medicare expanded coverage of immunosuppressive medications and immunosuppressive treatment and post-transplant care have improved over time, said Dr. Purnell, an Assistant Professor of Transplant Surgery and Epidemiology. This may have differentially benefited black transplant patients who historically had been disproportionately burdened by immunologic issues, she said.