Geographic patterns of end-stage renal disease and kidney transplants in the Midwestern United States

• The kidney transplant rate is 73% lower among black ESRD patients than for white in the study region.
• Native American and black population groups have lower overall spatial access scores than other groups.
• Patients in rural counties have higher ESRD incidence rates and lower access scores than those in urban counties.
• Average driving time is 67 min longer for patients in rural counties than urban.
• 76% of counties with highest class of ESRD incidence rates are in the lowest two categories of spatial accessibility.

This research analyzes geographic patterns of ESRD incidence and kidney transplantation at county level in an area that covers 11 states in the Midwestern US from 2004 to 2011. We investigate whether variations in ESRD incidence exist among white, black, and Native American population groups, and the degree to which disparities existed with respect to access to kidney transplantation, and with respect to rural and urban counties. Spatial clusters of ESRD incidence rates are detected using global Moran's I and local Getis-Ord Gi∗ statistic. Spatial accessibility to transplant centers is evaluated using the enhanced two-step floating catchment area method where dissimilarities due to varying travel times and ESRD incidence rates result in differences in spatial access among the groups. Results show that while similar age-adjusted ESRD incidence rates hold for white and black population groups in urban counties, the kidney transplant rate is 73% lower among black patients than for whites in the study area. A lack of transplant centers in locations that correspond to strongly clustered age-adjusted ESRD incidence rates in southern Missouri and central South Dakota, contribute to lower spatial access indices in these counties. The results of the analyses capture varying patterns of ESRD incidence rates and kidney transplants in this Midwestern region and highlight spatial disparities for certain population groups.