Donor Sex Disparities in CKD Progression: A UNOS Analysis

Background: Living donor kidney transplantation (LDKT) remains the gold standard for the treatment of ESRD. However, there is scarce prospective data on long term outcomes for kidney donors. Retrospective studies with follow-up time of 10 years or more have shown a modest risk increase in all-cause mortality, hypertension and ESRD. As a higher proportion of living donors are female, we aim to assess sex disparities amongst kidney donors requiting listing for kidney transplantation (KT). Methods: We queried the UNOS/OPTN database for all adults listed for a primary KT between 1/1/2014 and 12/31/23. Probabilistic linkage was used to link the donor record to the waitlist information. Comprehensive statistical methods were applied to assess the development over time and to describe possible sex differences. Results: 51,700 primary LDKTs performed during the study period, 64% of donors were female (p=0.007). In contrast, of 519 donors (1%) who were listed for KT, 64% were male (p<0.0001) (fig 1). Baseline characteristics were similar in between the groups (table 1). Only males were more likely to have hypertension and diabetes at the time of listing. There was no significant difference in time from donation to listing between the groups. Conclusion: Male kidney donors are more likely to progress to require kidney transplant listing. Higher rates of diabetes and hypertension are likely associated with faster decline in kidney function amongst males. Prospective research assessing long term outcomes in donors is warranted.Table 1. Baseline CharacteristicsFigure 1. Rate of female LDKT donors and waitlisting