Preoperative Toxoplasma gondii serostatus does not affect long-term survival of cardiac transplant recipients. Analysis of the Spanish Heart Transplantation Registry

Abstract Background It's unclear whether pre-transplant T. gondii seropositivity is associated with impaired survival in heart transplant recipients. Objectives To test the above-mentioned hypothesis in the Spanish Heart Transplantation Registry. Methods Post-transplant outcomes of 4048 patients aged >16years who underwent first, single-organ heart transplantation in 17 Spanish institutions from 1984 to 2014 were studied. Long-term post-transplant survival and survival free of cardiac death or retransplantation of 2434 (60%) T. gondii seropositive recipients and 1614 (40%) T. gondii seronegative recipients were compared. Results T. gondii seropositive recipients were older, had higher body mass index, and presented higher prevalence of hypertension, hypercholesterolemia, COPD and Cytomegalovirus seropositivity than T. gondii seronegative recipients. In univariable analysis, pre-transplant T. gondii seropositivity was associated with increased post-transplant all-cause mortality (non-adjusted HR 1.15; 95% CI 1.04–1.26). However, this effect was no longer statistically significant after multivariable adjustment by recipient's age and sex (adjusted HR 1.01, 95% CI 0.92–1.11). Extended multivariable adjustment by other potential confounders showed similar results (adjusted HR 0.99, 95% CI 0.89–1.11). T. gondii seropositivity had no significant effect on the composite outcome cardiac death or retransplantation (non-adjusted HR 1.08, 95% CI 0.95–1.24, p =0.235). The distribution of the causes of death was comparable in T. gondii seropositive and T. gondii seronegative recipients. No statistically significant impact of donor's T. gondii serostatus or donor-recipient T. gondii serostatus matching on post-transplant survival was observed. Conclusions Our analysis did not show a significant independent effect of preoperative T. gondii serostatus on long-term outcomes after heart transplantation.