Accepting kidneys from older living donors: impact on transplant recipient outcomes.

Older living kidney donors are regularly accepted. Better knowledge of recipient outcomes is needed to inform this practice. This retrospective cohort study observed kidney allograft recipients from Ontario, Canada between January 2000 and March 2008. Donors to these recipients were older living (≥ 60 years), younger living, or standard criteria deceased (SCD). Review of medical records and electronic healthcare data were used to perform survival analysis. Recipients received 73 older living, 1187 younger living and 1400 SCD kidneys. Recipients of older living kidneys were older than recipients of younger living kidneys. Baseline glomerular filtration rate (eGFR) of older kidneys was 13 mL/min per 1.73 m² lower than younger kidneys. Median follow-up time was 4 years. The primary outcome of total graft loss was not significantly different between older and younger living kidney recipients [adjusted hazard ratio, HR (95%CI): 1.56 (0.98-2.49)]. This hazard ratio was not proportional and increased with time. Associations were not modified by recipient age or donor eGFR. There was no significant difference in total graft loss comparing older living to SCD kidney recipients [HR: 1.29 (0.80-2.08)]. In light of an observed trend towards potential differences beyond 4 years, uncertainty remains, and extended follow-up of this and other cohorts is warranted.