Patient and Kidney Allograft Survival with National Kidney Paired Donation

Abstract

Background and objectives: In the United States, kidney paired donation networks have facilitated an increasing proportion of kidney transplants annually, but transplant outcome differences beyond 5 years between paired donation and other living donor kidney transplant recipients have not been well described.

Design, setting, participants, & measurements: Using registry-linked data, we compared National Kidney Registry (n=2363) recipients to control kidney transplant recipients (n=54,497) (February 2008 to December 2017). We estimated the risk of death-censored graft failure and mortality using inverse probability of treatment weighted Cox regression. The parsimonious model adjusted for recipient factors (age, sex, black, race, body mass index ≥30 kg/m², diabetes, previous transplant, preemptive transplant, public insurance, hepatitis C, eGFR, antibody depleting induction therapy, year of transplant), donor factors (age, sex, Hispanic ethnicity, body mass index ≥30 kg/m²), and transplant factors (zero HLA mismatch).

Results: National Kidney Registry recipients were more likely to be women, black, older, on public insurance, have panel reactive antibodies >80%, spend longer on dialysis, and be previous transplant recipients. National Kidney Registry recipients were followed for a median 3.7 years (interquartile range, 2.1-5.6; maximum 10.9 years). National Kidney Registry recipients had similar graft failure (5% versus 6%; log-rank P=0.2) and mortality (9% versus 10%; log-rank P=0.4) incidence compared with controls during follow-up. After adjustment for donor, recipient, and transplant factors, there no detectable difference in graft failure (adjusted hazard ratio, 0.95; 95% confidence interval, 0.77 to 1.18; P=0.6) or mortality (adjusted hazard ratio, 0.86; 95% confidence interval, 0.70 to 1.07; P=0.2) between National Kidney Registry and control recipients.

Conclusions: Even after transplanting patients with greater risk factors for worse post-transplant outcomes, nationalized paired donation results in equivalent outcomes when compared with control living donor kidney transplant recipients.

Keywords: Hispanic Americans; United States; age factors; allografts; body mass index; diabetes mellitus; donor exchange; female; follow-up studies; hepatitis C; humans; incidence; kidney donation; kidney transplantation; living donors; registries; renal dialysis; risk factors; semantic web; sex factors; transplant recipients.

Graphical abstract

Figure 1.

Death-censored graft failure cumulative incidence by participation in the National Kidney Registry. (A) Cumulative death-censored graft failure comparing national kidney registry recipients (dashed line) to control living donor recipient during the study period (solid line). (B) Cumulative death-censored graft failure comparing national kidney registry recipients (dashed line) to control unrelated living donor recipient during the study period (solid line). Unrelated recipients were identified using the donor/recipient relationship as captured in the national registry. (C) Cumulative death-censored graft failure comparing national kidney registry recipients (dashed line) to control paired donation living donor recipient during the study period (solid line). Paired donation recipients outside the national kidney registry were identified using the donor/recipient relationship as captured in the national registry.

Figure 2.

Mortality cumulative incidence by participation in the National Kidney Registry. (A) Cumulative mortality comparing national kidney registry recipients (dashed line) to control living donor recipient during the study period (solid line). (B) Cumulative mortality comparing national kidney registry recipients (dashed line) to control unrelated living donor recipient during the study period (solid line). Unrelated recipients were identified using the donor/recipient relationship as captured in the national registry. (C) Cumulative mortality comparing national kidney registry recipients (dashed line) to control paired donation living donor recipient during the study period (solid line). Paired donation recipients outside the national kidney registry were identified using the donor/recipient relationship as captured in the national registry.