Risk of ESKD in related older living kidney donors

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.