Center Variability in Acute Rejection and Biliary Complications After Pediatric Liver Transplantation

Abstract

Transplant center performance and practice variation for pediatric post-liver transplantation (LT) outcomes other than survival are understudied. This was a retrospective cohort study of pediatric LT recipients who received transplants between January 1, 2006, and May 31, 2017, using United Network for Organ Sharing (UNOS) data that were merged with the Pediatric Health Information System database. Center effects for the acute rejection rate at 1 year after LT (AR1) using UNOS coding and the biliary complication rate at 1 year after LT (BC1) using inpatient billing claims data were estimated by center-specific rescaled odds ratios that accounted for potential differences in recipient and donor characteristics. There were 2216 pediatric LT recipients at 24 freestanding children's hospitals in the United States during the study period. The median unadjusted center rate of AR1 was 36.92% (interquartile range [IQR], 22.36%-44.52%), whereas that of BC1 was 32.29% (IQR, 26.14%-40.44%). Accounting for recipient case mix and donor factors, 5/24 centers performed better than expected with regard to AR1, whereas 3/24 centers performed worse than expected. There was less heterogeneity across the center effects for BC1 than for AR1. There was no relationship observed between the center effects for AR1 or BC1 and center volume. Beyond recipient and allograft factors, differences in transplant center management are an important driver of center AR1 performance, and less so of BC1 performance. Further research is needed to identify the sources of variability so as to implement the most effective solutions to broadly enhance outcomes for pediatric LT recipients.

Figure 1:

Unadjusted rates of AR1 and BC1 by center, with centers ranked by increasing overall LT volume (inclusive of re-transplants and multiorgan transplants) between 2006–2017 (A) and average yearly primary LT alone volume between 2013–2017 (B)

Figure 2:

Center effects for AR1 (A) and BC1 (B) with corresponding 95% CIs. ★: p-value <0.05 Note: Each center effect is a rescaled odds ratio (i.e., original center-specific OR, divided by the center-size weighted average OR). The center effects average to 1.0. Centers are ranked from top-to-bottom from largest to smallest effect within each outcome and by average yearly primary LT alone volume between 2013–2017.

Figure 3:

Left panel demonstrates center induction practices with corresponding center effects and 95% CIs for AR1 on the right. Each row represents one center (N=24) with centers ranked from top-to-bottom by increasing induction use. ★: p-value <0.05

Figure 4:

Left panel demonstrates center effects and 95% CIs for BC1 with corresponding center biliary complication treatment practices on the right. The panel on the right shows the % of biliary complications treated non-surgically, with a surgical procedure, or without invasive treatment by center. Each row represents one center (N=24) with centers ranked from by increasing BC1 center effect. ★: p-value <0.05