Complications of hepatitis C virus (HCV) infection are primarily related to the development of advanced fibrosis.
Baseline data from a prospective community-based cohort study of 204 persons with chronic hepatitis C virus (HCV) infection were used for analysis. The outcome was fibrosis score on biopsy and the primary predictor evaluated was daily cannabis use.
The median age of the cohort was 46.8 years, 69.1% were male, 49.0% were Caucasian, and the presumed route of infection was injection drug use in 70.1%. The median lifetime duration and average daily use of alcohol were 29.1 years and 1.94 drink equivalents per day. Cannabis use frequency (within prior 12 months) was daily in 13.7%, occasional in 45.1%, and never in 41.2%. Fibrosis stage, assessed by Ishak method, was F0, F1–2 and F3–6 in 27.5%, 55.4% and 17.2% of subjects, respectively. Daily compared to non-daily cannabis use was significantly associated with moderate to severe fibrosis (F3–6 versus F1–2) in univariate [OR = 3.21 (95% CI, 1.20–8.56), p = 0.020] and multivariate analyses (OR = 6.78, (1.89–24.31), p=0.003). Other independent predictors of F3–6 were ≥11 portal tracts (compared to <5, OR = 6.92 (1.34–35.7), p=0.021] and lifetime duration of moderate and heavy alcohol use [OR per decade = 1.72 (1.02–2.90), p=0.044].
We conclude that daily cannabis use is strongly associated with moderate to severe fibrosis and that HCV-infected individuals should be counseled to reduce or abstain from cannabis use.