Delisting From the Kidney Transplant Wait-List: Native Americans Are the Most Disadvantaged.

Abstract

Background: Wait-listed Native Americans (NA) have lower rates of kidney transplantation than other ethnic groups. This disparity is hypothesized to arise from various medical and socioeconomic factors. The objective of this study is to evaluate the causes of delisting among Native American wait-listed patients. Methods: Using data from the Organ Procurement and Transplantation Network we evaluated the reasons for removal from the national wait-list, comparing NA populations with other ethnic groups from 1987 to 2010. To establish our initial results, we use a linear probability model, controlling for time invariant factors affecting all patients wait-listed at a given center (center fixed effects) and time-varying factors affecting all transplant centers in a given year (year fixed effects). (Standard errors are clustered at the center level to account for heteroskedasticity and spatial correlation among patients in a given center.) Results: Of the 492,866 registered patients removed from the wait-list during study period, 60% received an allograft (47% deceased donor and 13% live donor), 14 % died, 5% were deemed “too sick for transplant” and 1% were determined to be “medically unsuitable”. Regression analysis indicate that, relative to whites, being NA is associated with a 6 percentage point increase in the probability of dying on the wait-list(P<0.01),a 3.3 percentage point increase in the probability of being deemed too sick for transplant (P<0.01), and a 0.8 percentage point increase in the probability of being determined medically unsuitable for transplant (P<0.05). For these three wait-list outcomes, the magnitude of the differences between NA and whites exceed those between whites and African-Americans, Hispanics, or Asians. Conclusions: After controlling for year and center fixed effects, we found that, relative to other ethnic groups, wait-listed Native Americans are the most likely to die on the wait-list, be deemed medically unsuitable for transplant or be determined too sick to receive a transplant. Further research exploring the causes of this documented disparity, including behavioral, medical, and socioeconomic, will identify potential interventions, which could increase the rate of transplantation among wait-listed NA.