Association Between Early Immunosuppression Center Variability and One-Year Outcomes After Pediatric Liver Transplant

Despite the existence of institutional protocols, liver transplant centers often have variability in early immunosuppression practices. We aimed to measure within-center variability in early immunosuppression after pediatric liver transplant (LT) and examine its association with one-year outcomes.

We analyzed pediatric LTs from 2013 to 2018 in the United Network for Organ Sharing registry, with data aggregated by center. We categorized induction regimen as corticosteroids only vs. T-cell depleting antibody vs. non-T-cell depleting antibody. Primary exposures were coefficient of immunosuppression variability (CIV) in (1) induction and (2) mycophenolate mofetil (MMF) use. Primary outcomes were one-year graft survival, patient survival, and acute rejection rate within the first year after transplant.

The study cohort included 2542 LT recipients from 67 LT centers. Sixteen centers (24%) had no MMF variability; twenty-five centers (37%) had no induction variability. In multivariable analysis, induction CIV was associated with 2.72 times greater odds of acute rejection in the first year (OR 2.72; 95% CI 1.66-4.45; p < 0.001). MMF CIV was not associated with rejection (OR 1.22, 95% CI 0.66-2.25, p = 0.527). Neither one-year graft nor patient survival were associated with induction or MMF CIV.

Induction CIV is associated with higher one-year acute rejection odds and did not impact short-term graft or patient survival. Improved understanding of the reasons for high CIV will inform future work aiming to determine whether reducing variability may improve outcomes.