Living kidney donors who are biologically related to the recipient have higher risk for end-stage kidney disease (ESKD) compared with those who are unrelated to the recipient. This risk is greater for first-degree relatives than more distant relatives. To understand if this holds true for older donors, who were cleared for donation and might be past the peak-age for hereditary disease, we used donor data (SRTR) linked to ESKD registry data (CMS) and stratified donors by age (younger vs older [≥50 years]) and race (black, Hispanic, and white). Younger related donors of all racial groups had higher risk of ESKD compared with younger unrelated donors; however, only older related white and Hispanic donors had higher risk of ESRD compared with unrelated older donors (2.3-fold for white full-siblings and 1.9-fold for white parents/offspring; 3.3-fold for Hispanic full-siblings and 2.0-fold for Hispanic parents/offspring). Older related black donors did not have higher risk compared to older unrelated black donors (0.8-fold for black full-siblings and 0.5-fold for black parents/offspring). Our study points to an earlier age of onset of kidney disease in black donors with a family history of ESKD. Our findings call for programs that promote living donation among related older black donor candidates.

The authors have declared no competing interest.

This work was funded by grant number K24AI144954 (Segev) from the National Institute of Allergy and Infectious Diseases (NIAID) and K08AG065520-01 (Muzaale) from the National Institute on Aging

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