Study Explores Marijuana Use and Fibrosis in Women with HIV and Hepatitis C

A study in women coinfected with hepatitis C and HIV found that use of marijuana was not associated with progression to advanced liver fibrosis.

University researchers studied long-term effects of tetrahydrocannabinol (THC) from marijuana on fibrosis progression in women enrolled in the Women’s Interagency HIV Study. Results were published recently in the Oxford Journal of Clinical Infectious Diseases.

The hepatitis C virus (HCV) is a blood-borne disease that, left unchecked, can lead to fibrosis, cirrhosis, liver cancer, or the need for a liver transplant. The authors note that marijuana use has been associated with progression of liver fibrosis in retrospective analyses of patients with chronic hepatitis C and that other studies on the impact of THC use and liver fibrosis progression have reported conflicting results.

“Currently, marijuana has been legalized for medicinal and/or recreational use in 23 US states, as well as the District of Columbia, and its use in HIV/HCV-coinfected patients is common,” the authors stated in the article. “Given that it is becoming more widely available and more regularly consumed, it is critical to assess its clinical effects, including any negative impact of THC use on liver fibrosis progression.”

In this longitudinal analysis, researchers measured marijuana and alcohol use, quantifying it as average exposure per week. Liver fibrosis was categorized according to FIB-4 scores, as none, moderate or significant.

The study followed women who were coinfected with hepatitis C and HIV for an average of 11 years. Out of 575 women, 25% reported less than weekly THC use, 12% reported weekly use and 7% said that they used daily; just over half reported no THC use at all.

There were not many women who were heavy users of THC, but the study’s long follow-up period and study size enabled researchers to conclude that occasional THC is unlikely to contribute to fibrosis progression, according to the article.

“We found no evidence that THC accelerated fibrosis progression in women with HIV-HCV coinfection,” lead author Erin Kelly, MD, assistant professor at the University of Ottawa in Canada, said in an email. “Importantly, daily users were less prevalent in this cohort, therefore our results should not be extrapolated to this group.”

The possibility of underreported THC and alcohol use by the women in the study was noted as a limitation. In addition, liver biopsy was not conducted and fibrosis stage was instead determined using non-invasive tests.

Much like findings from other published studies, predictors of progression of significant fibrosis involving women in the WIHS study included the presence of baseline fibrosis, as well as entry CD4 count and HCV RNA level and ongoing alcohol consumption, according to the article.

“Fibrosis progression was associated with poor HIV control and alcohol use,” the authors concluded. “Clinicians should therefore counsel patients on limiting or excluding alcohol intake, in addition to optimizing medical treatment for HIV and HCV, as these factors are more important than THC use in modulating liver disease,” they advised.