Patients with a history of smoking weed have often been denied a potentially life-saving liver transplant, but a new study indicates that toking up needn’t be considered a risk factor in the operation.
Research published in this month’s issue of The American Journal of the Medical Sciences examined the results of liver transplants on individuals who use marijuana.
The researchers from the University of Alabama-Birmingham said they “performed a retrospective review of 111 patients who tested positive for marijuana on urine drug screen during initial [liver transplant] evaluation between February 2016 and January 2021,” while another “100 non-marijuana users who underwent [liver transplant] were cross matched for control.”
“Patient demographics, substance use history, and transplant decisions were recorded. Post-LT variables were also collected up to 1 year post surgery including postoperative infections, medication non-compliance, and continued substance use. Chi-square analysis was used to assess the association between pre-transplant marijuana use and post-transplant complications. Logistics regression was implemented to measure associations amongst the entire cohort,” they wrote.
Among the 111 marijuana users who were included in the study, 32, or 29%, received a liver transplant.
The authors said there was “no statistical difference in post-LT outcomes between marijuana and non-marijuana users, including incidence of cardiac, respiratory, renal, psychiatric, or neurological complications, as well as readmission rates post-surgery,” and there were also “no statistically significant associations between marijuana use with post-transplant bacterial or fungal infections, medication non-compliance, or continued substance use.”
“Our data indicates that marijuana is not associated with increased risk of postoperative noncompliance, other organ complications, infections, or death,” the researchers wrote in their conclusion. “As a single factor, marijuana may not need to be a contraindication for [liver transplant].”
The findings are significant in that marijuana use has frequently precluded otherwise eligible patients from receiving a liver transplant.
“Historically, institutions across the United States have deemed active marijuana use as an exclusion criterion for listing,” the authors wrote.
In its own write-up of the study, Salon reported that while 32 of the 111 patients received a liver transplant, the “remaining 79 were denied for varying reasons, including insurance or financial issues, with 41 explicitly denied for ‘continued marijuana use’ as one of several non-compliance problems,” and 11 who were “denied solely for using cannabis.”
Salon also flagged another study, published last year in The Journal of Clinical and Translational Research, that found “that marijuana use did not have an adverse impact on post-[liver transplant] outcomes,” although it said “further studies utilizing larger cohorts are warranted.”
Salon has more context on all of the research on the matter.
“In all of these studies, the research was retrospective, which limits the conclusions that can be drawn. A randomized, clinical trial would be a better study design, but can be much more expensive and difficult to implement,” the outlet reported. “Furthermore, it wasn’t always possible to determine the frequency of marijuana use or the type of cannabis consumed.”
As cannabis use has proliferated in the United States––and as laws governing its use have changed dramatically in the last decade––so too has the need for marijuana-related research.
According to the Centers for Disease Control and Prevention, marijuana is “the most commonly used federally illegal drug in the United States; 48.2 million people, or about 18% of Americans, used it at least once in 2019.” Medical marijuana is legal in 37 states, while recreational pot use is legal in 19.
But because cannabis remains illegal on the federal level, research and medical accessibility have often been limited.
