Background Approximately 50% of heart transplant (HT) programs utilize
induction therapy (IT) with interleukin-2 receptor antagonists (IL2RA)
or polyclonal anti-thymocyte antibodies (ATG). Methods Adult HT
recipients were identified in the UNOS Registry between 2010 and 2020.
We compared mortality between IT strategies with competing risk
analysis. Results A total of 28 634 HT recipients were included in the
study (50.1% no IT, 21.3% ATG, 27.9% IL2RA, .7% alemtuzumab, .01%
OKT3). Adjusted all-cause, 30 day and 1 year mortality were lower among
those treated with IT than no IT (sub-hazard ratio [SHR] .87, 95% CI
.79-.96, SHR .86, .76-.97, SHR .76, .63-.93, P = .007, respectively). In
propensity score matching analysis IT was associated with lower 30-day
and 1-year mortality. IL2RA had higher all-cause and 1-year mortality
than ATG (SHR 1.41, 95% CI 1.23-1.69 and 1.55, 95% CI 1.29-1.88,
respectively). Utilization of IT was associated with significantly lower
risk of treated rejection at 1 year after HT compared with no IT
(relative risk ratio [RRR] .79) and similarly ATG compared with IL2RA
(RRR .51). Conclusion IT was associated with lower mortality and treated
rejection episodes than no IT. IL2RA is the most used IT approach but
ATG has lower risk of treated rejection and mortality
