Association of Cold Ischemia Time With Acute Renal Transplant Rejection

Abstract

Background: Kidney transplantation holds much promise as a treatment of choice for patients with end-stage kidney disease. The impact of cold ischemia time (CIT) on acute renal transplant rejection (ARTR) remains to be fully studied in a large cohort of renal transplant patients.

Methods: From the Organ Procurement and Transplantation Network database, we analyzed 63 798 deceased donor renal transplants performed between 2000 and 2010. We assessed the association between CIT and ARTR. We also evaluated the association between recipient age and ARTR.

Results: Six thousand eight hundred two (11%) patients were clinically diagnosed with ARTR. Longer CIT was associated with an increased risk of ARTR. After multivariable adjustment, compared with recipients with CIT < 12 hours, the relative risk of ARTR was 1.13 (95% confidence interval, 1.04-1.23) in recipients with CIT ≥ 24 hours. The association of CIT and ARTR was more pronounced in patients undergoing retransplantation: compared with recipients with CIT less than 12 hours, the relative risk of ARTR was 1.66 (95% confidence interval, 1.01-2.73) in recipients with CIT of 24 hours or longer. Additionally, older age was associated with a decreased risk of ARTR. Compared with recipients aged 18 to 29 years, the relative risk of ARTR was 0.50 (95% confidence interval, 0.45-0.57) in recipients 60 years or older. Longer CIT was also associated with increased risk of death-censored graft loss. Compared with recipients with CIT less than 12 hours, the hazard ratio of death-censored graft loss was 1.22 (95% confidence interval, 1.14-1.30) in recipients with CIT of 24 hours or longer.

Conclusions: Prolonged CIT is associated with an increased risk of ARTR and death-censored graft loss. Older age was associated with a lower risk of ARTR.

FIGURE 1.

Risk of ARTR declines with older recipient age. Recipients were grouped by decade of life and the association of age with ARTR was evaluated with logistic regression analysis. The odds ratio of ARTR was lower among older recipients compared with younger recipients (P value <0.001). The multivariable analysis adjusted for CIT, age of the donors, sex of the recipients and donors, ethnicity of the recipients and donors, recipient BMI, HLA mismatching, extended criteria donor, donation after circulatory death, CPRA, cause of death for the donor, dialysis vintage, retransplantation, and year of transplantation. Confidence intervals for the odds ratios are shown below the data points.