Donor tobacco smoking is associated with postoperative thrombosis after primary liver transplantation

Background: Thrombosis after liver transplantation is a leading cause of graft loss, morbidity, and mortality. Several known recipient- and surgery-related characteristics have been associated with increased risk of thrombosis after transplantation. Potential donor-related risk factors, however, remain largely undefined.

Objectives: We aimed to identify risk factors for early post-transplantation thrombosis (<90 days) and to determine the impact of early postoperative thrombosis on long-term graft and patient survival.

Patients/methods: A post-hoc analysis was performed of an observational cohort study including all primary, adult liver transplantations performed between 1993-2018. Donor-, recipient-, and surgery-related characteristics were collected. Competing risk model analyses and multivariable regression analyses were performed to identify risk factors for developing early post-transplant thrombosis and graft failure.

Results: From a total of 748 adult liver transplantations, 58 recipients (7.8%) developed a thrombosis after a median of 7 days. Post-transplantation thrombotic events included 25 hepatic artery thrombosis, 13 portal vein thrombosis, and 22 other thrombotic complications. Donor history of smoking was independently associated with early postoperative thrombosis (OR 2.42; 95% CI, 1.29-4.52). Development of early post-transplant thrombosis was independently associated with patient mortality (HR 3.61; 95%CI 1.54-8.46) and graft failure (HR 5.80, 95%CI 3.26-10.33), respectively.

Conclusion: Donor history of smoking conveys a more than two-fold increased risk of thrombosis after liver transplantation, independent of other factors. Post-transplant thrombosis was independently associated with decreased patient and graft survival.

Keywords: Graft survival; Hepatic artery thrombosis; Liver transplantation; Portal vein thrombosis; Risk factors.