Impact of Acuity Circles Policy on ABO Blood Type-Related Waitlist Outcomes in Liver Transplantation

Purpose: We aimed to assess the impact of Acuity Circles (AC) allocation policy on ABO blood type–related disparities in liver transplant waitlist outcomes. Methods: This was a retrospective cohort study using national registry data from 2/2002-9/2023. Adults listed for liver transplant were included, excluding those with hepatocellular carcinoma exceptions and multi-organ listings. Adjusted Fine-Gray competing risk regression was used to evaluate transplant and waitlist mortality outcomes before and after AC policy implementation. Findings: A total 179,376 waitlist candidates were included. Median time to transplant decreased across ABO groups in the post-AC era. In adjusted models, there was a significant change in time to transplant among ABO groups across eras ( p <0.001). There was a 10.7% disparity reduction in time to transplant for type B versus type AB (0.694 SHR post-AC vs. 0.627 SHR pre-AC), and a 4.3% disparity reduction in time to transplant for type O versus type AB (SHR 0.511 post-AC vs. 0.490 pre-AC). While there was a significant reduction in overall waitlist mortality in the post-AC era (SHR 0.605, 95% CI 0.486-0.753, P <0.001), there was no significant interaction between ABO group policy and era ( p =0.74). Conclusion: AC policy yielded more equitable transplant access overall by recipient ABO type, in particular for patients with type B blood.