Choosing between multiple living kidney donors, or evaluating offers in kidney paired donation, can be challenging because no metric currently exists for living donor quality. Furthermore, some deceased donor kidneys can result in better outcomes than some living donor kidneys, yet there is no way to compare them on the same scale. To better inform clinical decision-making, we created a living kidney donor profile index (LKDPI) on the same scale as the deceased donor KDPI, using Cox regression and adjusting for recipient characteristics. Donor age over 50 (HR per 10y = 1.151.241.33), elevated body mass index (BMI) (HR per 10 units = 1.011.091.16), African-American race (HR= 1.151.251.37), cigarette use (HR=1.091.161.23), as well as ABO incompatibility (HR= 1.031.271.58), HLA B (HR= 1.031.081.14) mismatches, and DR (HR= 1.041.091.15) mismatches were associated with greater risk of graft loss after living donor transplantation (all p<0.05). Median (IQR) LKDPI score was 13 (1–27); 24.2% of donors had LKDPI<0 (less risk than any DD kidney), and 4.4% of donors had LKDPI>50 (more risk than the median DD kidney). The LKDPI is a useful tool for comparing living donor kidneys to each other and to deceased donor kidneys.

At autopsy, the time that has elapsed since the time of death is routinely documented and noted as the postmortem interval (PMI). The PMI of human tissue samples is a parameter often reported in research studies and comparable PMI is preferred when comparing different populations, i.e., disease versus control patients. In theory, a short PMI may alleviate non-experimental protein denaturation, enzyme activity, and other chemical changes such as the pH, which could affect protein and nucleic acid integrity. Previous studies have compared PMI en masse by looking at many different individual cases each with one unique PMI, which may be affected by individual variance. To overcome this obstacle, in this study human hippocampal segments from the same individuals were sampled at different time points after autopsy creating a series of PMIs for each case. Frozen and fixed tissue was then examined by Western blot, RT-PCR, and immunohistochemistry to evaluate the effect of extended PMI on proteins, nucleic acids, and tissue morphology. In our results, immunostaining profiles for most proteins remained unchanged even after PMI of over 50 h, yet by Western blot distinctive degradation patterns were observed in different protein species. Finally, RNA integrity was lower after extended PMI; however, RNA preservation was variable among cases suggesting antemortem factors may play a larger role than PMI in protein and nucleic acid integrity.

IMPORTANCE Living kidney donation is associated with increased long-term risk of end-stage renal disease (ESRD). An early postdonation marker of ESRD risk could improve postdonation risk assessment and counseling for kidney donors and allow early intervention for donors at increased risk.OBJECTIVE To determine the association between renal function in the first 6 months postdonation and subsequent risk of ESRD in kidney donors. DESIGN, SETTING, AND PARTICIPANTSThis secondary analysis of a prospective national cohort uses a population-based registry of all living kidney donors in the United States between