Marijuana Consumption in Liver Transplant Recipients

Marijuana is legalized for either medical or recreational use in over half of the states in the United States and in Canada, but many transplant centers will not list patients who are using marijuana. However, the effect of marijuana on transplant outcomes remains unclear. Thus, we performed a retrospective analysis of all adult (≥18 years old) liver transplant patients treated at our center between 2007 and 2017. Patients were grouped according to their marijuana use and tobacco smoking status. We also evaluated tobacco smoking status for the comparative evaluation. Posttransplant morbidity, mortality, and graft survival were evaluated. In total, 316 patients were included: 171 (54%) patients were tobacco smokers (70 current; 101 former), 81 (26%) patients were marijuana smokers (13 current; 68 former), and 64 (20#x0025;) patients were both marijuana and tobacco smokers. A total of 136 (43%) reported never smoking marijuana or tobacco. After adjustment, current tobacco users were over 3 times as likely to die within 5 years compared with never users (hazard ratio [HR], 3.25; 95% confidence interval [CI], 1.63-6.46; P < 0.001), but no difference was seen between current/former and never marijuana users (HR, 0.52; 95% CI, 0.26-1.04; P = 0.06). No significant differences in inpatient respiratory complications, reintubation, or >24-hour intubation was seen. Overall, pretransplant marijuana use, past or current, does not appear to impact liver transplant outcomes, though tobacco smoking remains detrimental.