Daily cannabis use: a novel risk factor of steatosis severity in patients with chronic hepatitis C.

BACKGROUND & AIMS: Steatosis is highly prevalent in patients with chronic hepatitis C (CHC) and has been reported to increase fibrosis and reduce the rate of viral eradication. Two recent studies indicate that endocannabinoids promote experimental steatosis via activation of hepatic CB1 receptors. We therefore investigated the impact of cannabis smoking on steatosis severity during CHC. METHODS: A total of 315 consecutive patients with untreated CHC undergoing liver biopsy were included. Detailed histories of recent cannabis, alcohol, and tobacco use were recorded. Steatosis, activity, and fibrosis stage were assessed by 2 pathologists according to METAVIR. Marked steatosis was defined as >/=30%. Patients were categorized as cannabis nonusers (63.5%), occasional cannabis smokers (12.4%), or daily cannabis smokers (24.1%). RESULTS: Multivariate analysis identified 6 predictors of marked steatosis: daily cannabis use (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.01-4.5]), activity grade >/=A2 (OR, 2.1; 95% CI, 1.0-4.3), genotype 3 (OR, 5.4; 95% CI, 2.6-11.3), hyperglycemia or diabetes (OR, 5.1; 95% CI, 1.8-15.0), body mass index >27 kg/m(2) (OR, 2.1; 95% CI, 1.0-4.3), and serum HCV RNA load (OR, 1.7; 95% CI, 1.0-2.9). Upon adjustment of HCV genotype (3 vs non-3) or alcohol intake (<30 g/day vs >/=30 g/day), marked steatosis was more frequent in daily cannabis users compared with occasional users and nonusers (P = .03 and P = .008, respectively). CONCLUSIONS: Our results identify daily cannabis smoking as a novel independent predictor of steatosis severity during CHC and strongly argue for a steatogenic role of the cannabinoid system. Cannabis use should be discouraged in patients with CHC.

Daily cannabis smoking as a risk factor for progression of fibrosis in chronic hepatitis C.

Cannabinoids present in Cannabis sativa (marijuana) exert biological effects via cannabinoid receptors CB1 and CB2. We recently demonstrated that CB1 and CB2 receptors regulate progression of experimental liver fibrosis. We therefore investigated the impact of cannabis smoking on fibrosis progression rate in patients with chronic hepatitis C (CHC). Two hundred seventy consecutive untreated patients with CHC of known duration undergoing liver biopsy were studied. Demographic, epidemiological, metabolic, and virological data were recorded, and detailed histories of cannabis, alcohol, and tobacco use over the span of hepatitis C virus infection were obtained. Fibrosis stage, steatosis, and activity grades were scored according to Metavir system. Patients were categorized as noncannabis users (52.2%), occasional users (14.8%), or daily users (33.0%), and the relationship between cannabis use and fibrosis progression rate (FPR) or fibrosis stage was assessed. On multivariate analysis, six factors were independently related to a FPR greater than 0.074 (median value of the cohort): daily cannabis use (OR = 3.4 [1.5-7.4]), Metavir activity grade A2 or higher (OR = 5.4 [2.9-10.3]), age at contamination of more than 40 years (OR = 10.5 [3.0-37.1]), genotype 3 (OR = 3.4 [1.5-7.7]), excessive alcohol intake (OR = 2.2 [1.1-4.5]), and steatosis (OR = 2.0 [1.0-4.1]). Daily cannabis use was also an independent predictor of a rapid FPR (>0.15) (OR = 3.6 [1.5-7.5]). Finally, severe fibrosis (> or =F3) was also predicted by daily cannabis use (OR = 2.5 [1.1-5.6]; P = .034), independently of Metavir activity grade, excessive alcohol intake, age at liver biopsy, steatosis, and tobacco smoking. In conclusion, daily cannabis smoking is significantly associated with fibrosis progression during CHC. Patients with ongoing CHC should be advised to refrain from regular cannabis use.