Smoking increases recurrent viral hepatitis after liver transplantation
Smoking tends to be common among liver transplant recipients, yet until recently, few studies had been conducted to assess whether tobacco habits affect post-liver transplant outcomes. A research team from the McGill University Health Centre (MUHC) launched their study with the aim of evaluating the effect smoking can have on a range of complications following liver transplantation. Their research was published in the July issue of Liver Transplantation.
A significant finding from the study suggests that liver transplant recipients who smoke, or who have smoked, increase their risk of viral hepatitis reinfection. The culprit: tobacco. The main ingredient of cigarettes, pipe tobacco and cigars may adversely affect immune system response in patients who receive a transplant due to viral hepatitis.
“Recurrent hepatitis C is almost universal if you wait long enough after a liver transplant, thus it is not something that is surprising,” says Dr. Peter Ghali, senior author of the paper and Program Director for Hepatology and Liver Transplantation at the MUHC. “What is surprising is how quickly it recurs in smokers.”
Worldwide, tobacco use causes more than five million deaths per year, with estimates suggesting that annual mortality rates could climb to more than eight million by 2030. Previous research reported that nearly 34 per cent of liver transplant recipients are active or former tobacco users. Moreover, medical evidence has shown that smoking increases biliary and vascular complications in the short-term and elevates risk of cardiovascular in the long-term among those receiving livers.
Analysis of demographics and post-transplantation complications was performed on data collected from primary liver transplant recipients over a 14-year period. Using data from the MUHC Liver Transplant database, the team identified 444 patients who received liver transplants between 1990 and 2004, of which 63 were repeat transplants.
Results show that 23 per cent of transplant recipients were active or ex-smokers and 78 per cent were non-smokers. For smokers, survival time with no recurrence of hepatitis was less than one year, and close to five years for non-smokers. Researchers found that patient survival and the time leading up to biliary complications - first rejection and depression post-transplantation - was not linked to smoking status. However, recurring viral hepatitis was strongly associated with smoking.
“The results would suggest that encouraging preoperative smoking cessation may be beneficial in improving patient outcomes following transplantation, says Dr. Mamatha Bhat, first author and Research fellow from the MUHC Division of Gastroenterology and Hepatology, who stresses that the findings do not suggest the denial of liver transplantation for those in need, but that transplant specialists be more vigilant in monitoring for complications in those candidates who continue to smoke.
About the study
The study was co-authored by Mamatha Bhat, Marc Deschenes, Myriam Martel, Philip Wong and Peter Ghali (Division of Gastroenterology and Hepatology, MUHC); Xianming Tan (Biostatistics Core Facility, Research Institute of the MUHC); Venkataramana Bhat (Department of Psychiatry, MUHC); and Peter Metrakos (Section of Transplant and Hepatopancreatobiliary, MUHC).
Read the study: