Heart transplant outcomes in patients with substance use disorder history: a nationwide cohort study using high-dimensional propensity score matching.

AIMS: History of substance use is assessed in potential heart transplantation (HT) evaluations. The evidence base for this highly consequential practice, linking substance use disorders (SUDs) with poor post-transplantation outcomes, presents methodological limitations. We conducted a retrospective cohort study to address these limitations using high dimensional propensity score matching to compare HT outcomes of patients with and without SUDs. METHODS AND RESULTS: Key outcomes included mortality, hospitalization, and organ rejection rates, controlling for confounders. A national dataset of electronic health records of >120 million patients in the USA (2015-23) was used to identify HT patients with SUDs (n = 808) and controls (n = 7066), matched for medical comorbidities and demographic variables. Only after adjusting for sociodemographic and comorbidities of HT recipients, the results revealed no significant differences between groups with and without SUDs at 1 year in mortality [odds ratio (OR) = 0.96 (95% confidence interval, CI): 0.54, 1.69, P = 0.88], hospitalization [OR = 1.02 (95% CI: 0.83, 1.25), P = 0.840)], organ rejection rates [OR = 0.96 (95% CI: 0.78, 1.18), P = 0.670)], nor at 5 years in mortality [hazard ratio (HR) = 1.15 (95% CI: 0.82, 1.61), P = 0.410] and organ rejection [HR = 0.98 (95% CI: 0.84, 1.14), P = 0.810]. CONCLUSION: Future studies must consider confounding factors when evaluating transplant criteria and outcomes in patients with SUDs.