Anatomical Size Disparities in Liver Transplantation: Imaging‐Derived Abdominal Dimensions and Their Association With Waitlist Outcomes
Rafal Mazur, Alyssa Stetson, Alissa Cutrone, David Cron, Joel Adler, Shimul Shah, Heidi YehABSTRACT
Background
The objective of this study is to evaluate the association between two imaging‐derived measures—anteroposterior diameter (APD) and lateral abdominal wall–IVC distance (L‐IVC)—and liver transplant (LT) waitlist outcomes.
Methods
Retrospective cohort study of 520 adult LT candidates listed at a single academic transplant center from January 1, 2015, to December 31, 2023. APD and L‐IVC were measured using cross‐sectional abdominal imaging and categorized into three groups using interquartile thresholds: APD (<15.0 cm, 15.0–20.0 cm, >20.0 cm) and L‐IVC (<10.0 cm, 10.0–12.5 cm, ≥12.5 cm). The primary outcome was time to LT; the competing outcome was waitlist removal due to death or clinical deterioration. Sub‐distribution hazard ratios (SHRs) were estimated using competing risks regression. Harrell's C‐statistic and bootstrap comparisons were used to evaluate discrimination versus height, BMI, and body surface area (BSA).
Results
Among 520 candidates (mean [SD] age, 55.7 [10.9] years; 37.5% women), small APD (SHR = 0.51; CI: 0.33–0.72; p = 0.02) and L‐IVC (SHR = 0.39; CI: 0.21–0.62: p < 0.001) were associated with lower transplant probability. Candidates with larger APD (>20.0 cm) had the highest risk of waitlist removal (SHR = 1.47; CI:1.02–1.87; p = 0.04). L‐IVC was most strongly associated with LT (C‐statistic = 0.65) and waitlist removal (C‐statistic = 0.67). In sex‐stratified models, men with small APD or L‐IVC had significantly lower transplant probability, while women with mid‐range APD (15.0–20.0 cm) or L‐IVC ≥ 12.5 cm had the highest transplant likelihood.
Conclusion
Anatomical measurements derived from imaging are more strongly associated with liver transplant waitlist outcomes, outperforming height, BMI, and BSA.