Substantial variation in the acceptance of medically complex live kidney donors across US renal transplant centers

Concern exists about accepting live kidney donation from 'medically complex donors'--those with risk factors for future kidney disease. This study's aim was to examine variation in complex kidney donor use across US transplant centers. We conducted a retrospective cohort study of live kidney donors using organ procurement and transplantation network data. Donors with hypertension, obesity or estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) were considered medically complex. Among 9319 donors, 2254 (24.2%) were complex: 1194 (12.8%) were obese, 956 (10.3%) hypertensive and 392 (4.2%) had low eGFR. The mean proportion of medically complex donors at a center was 24% (range 0-65%). In multivariate analysis, donor characteristics associated with medical complexity included spousal relationship to the recipient (OR 1.29, CI 1.06-1.56, p < 0.01), low education (OR 1.19, CI 1.04-1.37, p = 0.01), older age (OR 1.01 per year, CI 1.01-1.02, p < 0.01) and non-US citizenship (OR 0.70, CI 0.51-0.97, p = 0.03). Renal transplant centers with the highest transplant volume (OR 1.26, CI 1.02-1.57, p = 0.03), and with a higher proportion of (living donation)/(all kidney transplants) (OR 1.97, CI 1.23-3.16, p < 0.01) were more likely to use medically complex donors. Though controversial, the use of medically complex donors is widespread and varies widely across centers.