Marijuana smoking is not associated with the promotion of liver disease in subjects coinfected with both hepatitis C and the human immunodeficiency virus (HIV), according to data published online in the journal Clinical Infectious Diseases.
Investigators at McGill University in Montreal and the University of Toronto assessed the impact of marijuana smoking on liver disease progression longitudinally in a cohort of nearly 700 subjects with HIV and the hepatitis C virus (HCV). Study participants at baseline reported having previously used cannabis, on average, some seven times per week, with 40 percent of subjects acknowledging having consumed cannabis daily. Participants were monitored over a median period of 32 months.
Investigators reported, “In this prospective analysis we found no evidence for an association between marijuana smoking and significant liver fibrosis progression in HIV/HCV coinfection.” Authors speculated that previously reported positive associations between cannabis smoking and liver disease progression were likely the result of “reverse causation due to self-medication.”
Researchers concluded: “[I]n this first prospective evaluation of liver disease progression among HIV-HCV infected persons, we could not demonstrate any important effect of marijuana on liver disease outcomes. A causal association is unlikely: hazard ratios were weak and … there was no dose-response relationship. It is likely that previous studies have been biased by reverse causality as patients use more marijuana to relieve symptoms as liver disease progresses.”
Subjects diagnosed with HIV and/or hepatitis C frequently report using cannabis to treat disease symptoms as well as the plethora of adverse side effects, such as nausea and appetite loss, associated with conventional drug therapies.
Full text of the study, “Marijuana Smoking Does Not Accelerate Progression of Liver Disease in HIV–Hepatitis C Coinfection: A Longitudinal Cohort Analysis,” appears online in Clinical Infectious Diseases. The study abstract appears online here.
By Paul Armentano, NORML Deputy Director