Living kidney donors ages 70 and older: recipient and donor outcomes

Abstract

Background and objectives: The profound organ shortage has resulted in longer waiting times and increased mortality for those awaiting kidney transplantation. Consequently, patients are turning to older living donors. It is unclear if an upper age limit for donation should exist, both in terms of recipient and donor outcomes.

Design, setting, participants, & measurements: In the United States, 219 healthy adults aged ≥70 have donated kidneys at 80 of 279 transplant centers. Competing risks models with matched controls were used to study the independent association between older donor age and allograft survival, accounting for the competing risk of recipient mortality as well as other transplant factors.

Results: Among recipients of older live donor allografts, graft loss was significantly higher than matched 50-to 59-year-old live donor allografts (subhazard ratio [SHR] 1.62, 95% confidence interval [CI] 1.16 to 2.28, P = 0.005) but similar to matched nonextended criteria 50-to 59-year-old deceased donor allografts (SHR 1.19, 95% CI 0.87 to 1.63, P = 0.3). Mortality among living kidney donors aged ≥70 was no higher than healthy matched controls drawn from the NHANES-III cohort; in fact, mortality was lower, probably reflecting higher selectivity among older live donors than could be captured in National Health and Nutrition Examination Survey III (NHANES-III; HR 0.37, 95% CI 0.21 to 0.65, P < 0.001).

Conclusions: These findings support living donation among older adults but highlight the advantages of finding a younger donor, particularly for younger recipients.

Figure 1.

Living kidney donors ≥70 (LD70) in the United States, by age (A), year (B), and center-level clustering (C). The line in (B) shows the best-fit linear trend across time. The curves in (C) illustrate the distribution of living donor kidney transplants across centers in the United States, stratified by donor age. The shift of the LD70 curve to the bottom right of the graph indicates that only a few centers performed live donor kidney transplants using donors aged ≥ 70.

Figure 2.

Cumulative incidence function (CIF) of graft failure (A) and Kaplan-Meier curve of patient survival (B) among recipients of kidneys from live donors age ≥70 (LD70) versus matched controls from among recipients of live donors age 50 to 59 (LD50) and nonextended criteria deceased donors aged 50 to 59 (DD50).

Figure 3.

Kaplan-Meier survival curve of live kidney donors aged ≥70, compared with matched healthy controls drawn from the National Health and Nutrition Examination Survey cohort.