*Purpose: The kidney donor risk index (KDRI) and percentile conversion kidney donor profile index (KDPI) were introduced with the Kidney Allocation System (KAS) to provide a continuous measure of kidney donor quality. Kidneys with a KDPI > 85% (KDPI₈₅) require additional informed consent from the recipient and are colloquially referred to as ‘high KDPI’. The median KDRI and the 85^th percentile KDRI (KDRI₈₅) are recalculated annually reflecting the procured kidneys from the year prior; consequently, the KDPI₈₅ cutoff changes every year. This study aims to examine changes in the KDRI₈₅ for procured kidneys over time, determine kidney utilization around the KDPI₈₅ cutoff and explore if there is a “high KDPI” labeling effect. We hypothesize that identical KDRI kidneys from different years would have different utilization based on being above or below the KDPI₈₅ cutoff.

*Methods: KDRI to KDPI Mapping Tables from 2012 to 2020 were used to determine the yearly KDRI₈₅ value. OPTN data was used to examine discard rates for KDPI 5% above and below this threshold. To determine if there was a High KDPI labeling effect, organ utilization after KAS implementation was examined for the subgroup of kidneys with a KDRI range that fell below the KDPI₈₅ cutoff (KDPI_LOW) and above the cutoff (KDPI_HIGH).

*Results: The KDRI₈₅ varied by year, between 1.768 and 1.888. Kidney discard rates were significantly lower for KDPI 81-85 kidneys compared with KDPI 86-90 kidneys, by 8.9% (36.2% vs 45.1%, p<0.001). Kidneys with a KDRI between 1.785 - 1.849 were classified as KDPI_HIGH in years 2015-2017 and KDPI_LOW in years 2018-2020 (Table 1). The discard rate was 44.9% when labeled as KDPI_HIGH and 39.1% when labeled as KDPI_LOW (p<0.01). The number of kidneys transplanted per donor decreased from 1.11 for KDPI_LOW to 0.94 for KDPI_HIGH (p<0.01)

*Conclusions: The KDRI₈₅ changes yearly, impacting which kidneys are labeled as KDPI_HIGH. Organ discard significantly increases for the 5% of kidneys above the KDRI₈₅ marker compared with below. For kidneys with identical KDRI, the label of “high KDPI” significantly increases discard rates. Consideration should be given to removing the high KDPI label and additional consent process.

« Back to 2022 American Transplant Congress