Donor characteristics associated with reduced graft survival: An approach to expanding the pool of kidney donors

Background. Availability of cadaveric kidneys for transplantation is far below the growing need, leading to longer waiting time and more deaths while waiting. Methods. Using national data from 1995 to 2000, we evaluated graft survival by donor characteristics and the rate of discard of retrieved organs, with the goal of increasing use of kidneys that are associated with increased risk of graft failure, that is, expanded donor kidneys. Results. Cox models identified four donor factors that independently predicted significantly higher relative risk of graft loss compared with a low-risk group. These factors included donor age, cerebrovascular accident as the cause of death, renal insufficiency (serum creatinine >1.5 mg/dL), and history of hypertension. Expanded donor kidneys were defined as those with relative risk of graft loss greater than 1.70 and included all donors aged 60 years and older and those aged 50 to 59 years with at least two of the other three conditions (cerebrovascular cause of death, renal insufficiency, hypertension). The expanded donor group accounted for 14.8% of transplanted kidneys. Among organs procured from expanded donors, 38% were discarded versus 9% for all other kidneys. The risk of graft loss of expanded donor kidneys was increased in both older and younger recipients but to a greater extent in those recipients older than 50 years. Conclusion. By identifying donor factors associated with graft failure, these analyses may help to expand the number of transplanted kidneys by increasing the utilization of retrieved cadaveric kidneys.