Kidney Transplant Outcomes in Indigenous People of the Northern Great Plains of the United States.

INTRODUCTION

Indigenous people experience higher rates of end-stage renal disease as well as negative predictive factors such as medical comorbidities, lower socioeconomic status, greater waitlist time, and fewer pre-emptive transplants that undermine kidney transplantation success. In addition, Indian tribal reservation-dwelling Indigenous people may also be disproportionately affected by poverty, geographical disadvantages, limited physician availability, lower health literacy and cultural beliefs that further reduce access to care. Historically, all racial minority groups have experienced higher rates of rejection events, graft failure and mortality relating to these inequalities. Recent data suggests that short-term outcomes in Indigenous people are comparable to other racial groups, but few studies have examined this effect in the northern Great Plains region.

METHODS

A retrospective database review was performed to determine outcomes of kidney transplantation in Indigenous people of the Northern Great Plains region. White and Indigenous people receiving a kidney transplant, between 2000 and 2018, at a single center, Avera McKennan Hospital in Sioux Falls, South Dakota, were included. Outcomes assessed between one month and 10 years post-transplant included estimated glomerular filtration rate, biopsy-proven acute rejection events, graft failure, patient survival, and death-censored graft failure. All transplant recipients had a minimum of one year of follow-up after transplant.

RESULTS

A total of 622 kidney transplant recipients were included (117 Indigenous and 505 White). Indigenous recipients were more likely to smoke, have diabetes, have higher immunologic risk, receive fewer living donor kidneys, and have longer wait-list times. In the five years following kidney transplant, there were no significant differences in renal function, rejection events, cancer, graft failure or patient survival. At 10 years post-transplant, Indigenous recipients had twice the all-cause graft failure (OR 2.06; CI 1.25-3.39) and half the survival (OR 0.47; CI 0.29-0.76), however this effect was not maintained once the effect of race was adjusted for sex, smoking status, diabetes, preemptive transplant, high panel reactive antibody status and transplant type.

CONCLUSIONS

This retrospective study found that, despite differences in baseline characteristics, a population of Indigenous kidney transplant recipients at a single center in the Northern Great Plains region had no statistically significant differences in transplant outcomes in the first five years after transplant compared with their White counterparts. Racial differences emerged in graft failure and patient survival at 10 years after renal transplant, with Indigenous individuals more likely to experience negative long-term outcomes, but once covariates were adjusted for, this effect became insignificant. A number of these covariates are potentially modifiable, and a greater focus on addressing risk factor disparity could help extend the excellent five-year kidney transplant outcomes into long-term success in Indigenous people.