BACKGROUND: Marijuana smoking is prevalent among hepatitis C virus-infected patients. The literature assessing the influence of marijuana on liver disease progression and hepatitis C virus antiviral treatment outcomes is conflicting.
METHODS: The authors evaluated hepatitis C virus RNA-positive patients followed at The Ottawa Hospital Viral Hepatitis Clinic (Ottawa, Ontario) from 2000 to 2009. Using The Ottawa Hospital Viral Hepatitis Clinic database and charts, information regarding demographics, HIV coinfection, alcohol use, liver biopsy results, treatment outcomes and self-reported marijuana use was extracted. Biopsy characteristics and hepatitis C virus antiviral treatment outcomes were assessed for association with categorized marijuana use by adjusted logistic regression; covariates were specified according to clinical relevance a priori.
RESULTS: Information regarding marijuana use was available for 550 patients, 159 (28.9%) of whom were using marijuana at the time of first assessment. Biopsy fibrosis stage and marijuana use data were available for 377 of these 550 (F0-2=72.3%). Overall, marijuana use did not predict fibrosis stage, inflammation grade or steatosis. Sustained virological response and marijuana use data were available for 359 of the 550 cohort participants; a total of 211 (58.8%) achieved a sustained virological response. Marijuana use was not associated with premature interruption of therapy for side effects, the likelihood of completing a full course of therapy or sustained virological response.
CONCLUSION: Marijuana use did not influence biopsy histology or alter key hard outcomes of hepatitis C virus antiviral therapy.