Center Geography or Center Practice? Decomposing Geographic Variation in Access to Kidney Transplantation Before...

Area of Science:

• Nephrology
• Transplant Surgery
• Health Policy

Background:

• Donor Service Area (DSA) was a major factor in deceased donor kidney transplantation (DDKT) rate disparities before KAS250.
• The impact of center-level practices on DDKT rate variation, both before and after KAS250, requires further investigation.

Purpose of the Study:

• To differentiate DDKT rate variations attributed to center practices, kidney distribution policies (DSAs, OPTN Regions), and geographic kidney scarcity.
• To analyze the impact of KAS250 on DDKT rate disparities across different geographic levels.

Main Methods:

• Utilized national transplant registry data to compare DDKT rates before and after KAS250 implementation.
• Employed multilevel Poisson regression to model candidate DDKT rates, adjusting for candidate factors.
• Calculated median incidence rate ratios (MIRR) to quantify variation attributed to DSAs, OPTN regions, states, census divisions, and centers.

Main Results:

• DSA-level disparities significantly decreased post-KAS250 (MIRR from 1.35 to 1.17).
• Under KAS250, center-level variation accounted for 93.4% of geographic DDKT rate variability, compared to 81.7% pre-KAS250.
• Center-level DDKT rates strongly correlated with offer acceptance rates (ρ = 0.60, p < 0.001).

Conclusions:

• Center practices, particularly offer acceptance rates, are the main drivers of geographic disparities in DDKT.
• KAS250 effectively reduced DSA-level disparities in kidney transplantation.
• Future allocation policy changes may have limited impact on substantially reducing geographic DDKT rate variations.