UCSF

Background

Data are limited on marijuana use and its impact on liver transplant (LT) waitlist outcomes. We aimed to assess the risk of waitlist mortality/delisting and likelihood of LT among prior marijuana users and to determine the prevalence and factors associated with marijuana use.

Methods

Retrospective cohort of adults evaluated for LT over 2 years at a large LT center. Marijuana use was defined by self-report in psychosocial assessment and/or positive urine toxicology. Ongoing marijuana use was not permitted for LT listing during study period.

Results

Eight hundred eighty-four adults were evaluated, and 585 (66%) were listed for LT (median follow-up, 1.4 years; interquartile range, 0.5-2.0). Prevalence of marijuana use was 48%, with 7% being recent users and 41% prior users. Marijuana use had statistically significant association with alcoholic cirrhosis (incidence rate ratio [IRR], 1.9) and hepatitis C (IRR, 2.1) versus hepatitis B, tobacco use (prior IRR, 1.4; recent IRR, 1.3 vs never), alcohol use (never IRR 0.1; heavy use/abuse IRR 1.2 vs social), and illicit drug use (prior IRR, 2.3; recent, 1.9 vs never). In adjusted competing risk regression, marijuana use was not associated with the probability of LT (prior hazard ratio [HR], 0.9; recent HR, 0.9 vs never) or waitlist mortality/delisting (prior HR, 1.0; recent HR, 1.0 vs never). However, recent illicit drug use was associated with higher risk of death or delisting (HR, 1.8; P = 0.004 vs never).

Conclusions

Unlike illicit drug use, marijuana use was not associated with worse outcomes on the LT waitlist. Prospective studies are needed to assess ongoing marijuana use on the LT waitlist and post-LT outcomes.