Study Suggests United States Should Practice Higher Kidney Donor Acceptance

The findings of a new study suggest that higher acceptance of kidneys from deceased donors who are older and have more comorbidities could provide significant survival benefits to the population of United States (US) wait-listed patients. The study was published in JAMA Internal Medicine.

To conduct this study, researchers appraised national registries from the US and France, respectively, to assemble cohorts comprised of all consecutive kidneys recovered for transplantation from donors who had died from brain or circulatory failure between January 2004 and December 2014. In the US, they recovered 156,089 kidneys from deceased donors between 2004 and 2014, of which 128,102 were transplanted, and 27,987 (17.9%) were discarded. In France, among 29,984 kidneys recovered between 2004 and 2014, 27,252 were transplanted, and 2,732 were discarded. Exclusion criteria was specified as living donor kidney transplants, multiorgan transplant recipients, kidneys that were offered to transplant centers but were never recovered, and patients with missing data to calculate the KDRI score.

The key endpoint of this study was kidney allograft discard. The secondary outcome was stipulated as allograft failure following transplantation surgery. The researchers utilized logistic regression to model organ acceptance and discard practices in both countries. Subsequently, they quantified data using computer simulation models the number of kidneys discarded in the US that a more aggressive system would have instead used for transplantation. Based on actual survival data, they quantified the additional years of allograft life that a redesigned US system would have saved. Study data were analyzed between September 2018, and April 5, 2019.

Results Indicate the Need for Policy Change

According to the results, the mean (SD) age of kidneys transplanted in the US was 36.51 (17.02) years juxtaposed to 50.91 (17.34) years in France (P < .001). The researchers observed nominal change in kidney quality in the US over time (mean [SD] kidney donor risk index [KDRI], 1.30 [0.48] in 2004 vs 1.32 [0.46] in 2014), whereas a steadily rising KDRI in France reflected a temporal trend of more aggressive organ use (mean [SD] KDRI, 1.37 [0.47] in 2004 vs 1.74 [0.72] in 2014; P < .001). They applied the French-based allocation model to the population of US deceased donor kidneys and found that 17,435 (62%) of kidneys discarded in the US would have instead been transplanted under the French system. Moreover, the study found that a redesigned system with more aggressive organ acceptance practices would generate an additional 132,445 allograft life-years in the US over the 10-year observation period.

“The high discard rate of deceased donor kidneys is a major concern for the US transplant field,” the study authors wrote in their conclusion.

“We found that the age and KDRI of US deceased donor kidneys remained stable from 2004 to 2014 in the United States, whereas the French transplant system responded to the organ shortage by accepting lower-quality kidneys, especially those from older donors. Policies designed to enhance the acceptance of donated kidneys in the United States could drive meaningful increases in the number of kidney transplants and bring the benefits of transplantation to thousands of wait-listed patients.”