16 Aug HIV plus Hepatitis C : Marjuana Did Not Worsen Liver Disease
Marina Klein, MD, MSc, FRCP(C)
Associate Professor of Medicine
McGill University Health Centre
Division of Infectious Diseases and Chronic Viral Illness Service
3650 Saint Urbain
Montreal, Quebec H2X 2P4
Disease in HIV–Hepatitis C Coinfection: A Longitudinal Cohort Analysis
MedicalResearch.com: What are the main findings of the study?
Dr. Klein: We showed that people with HIV and hepatitis C infection who smoked marijuana did not tend to progress more rapidly to liver fibrosis, liver cirrhosis or end-stage liver disease, even with increasing numbers of joints smoked per week. Previous studies that reported that marijuana was harmful to the liver were likely biased because they did not ensure that marijuana smoking occurred before the development of liver problems.
MedicalResearch.com: Were any of the findings unexpected?
Dr. Klein: It is clear from the basic science literature that cannabinoids can affect the liver, but the actual effect of smoking marijuana in humans is difficult to know since the liver possess both pro- and anti-fibrogenic cannabinoid receptors. Our results contradict the findings of three previously published cross-sectional studies. We think this was because marijuana is often used to control symptoms, so people who have more advanced liver problems may use more marijuana simply because they have more symptoms—this doesn’t mean that the marijuana has caused their liver disease. It was important to take into consideration the timing of marijuana smoking and liver disease outcomes. When we ensured that marijuana use preceded the development of liver disease, we could not show that it was harmful to the liver.
MedicalResearch.com: What should clinicians and patients take away from your report?
Dr. Klein: Smoking marijuana can help people living with HIV to manage pain or stimulate appetite, for example. However, because of prior studies it is generally believed that marijuana can lead to liver fibrosis. Physicians may therefore hesitate to prescribe marijuana where allowed, or to support their patients in an application for an authorization to possess marijuana for medical purposes under the Canadian Marihuana Medicinal Access Regulations because of the fear that it can affect liver health. Our study suggests that smoking marijuana should not worsen the liver health of HCV co-infected individuals who are already at a greater risk for liver disease.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Dr. Klein: In this study, we only looked at marijuana smoking because we didn’t have the data to investigate ingestion of marijuana or the use of medication containing cannabinoids such as marinol, so we don’t if our results can apply to these marijuana uses as well. Longer term follow-up would also be important to ensure that marijuana use is safe over the long term.
Marijuana Smoking Does Not Accelerate Progression of Liver Disease in HIV-Hepatitis C Coinfection: A Longitudinal Cohort Analysis.
Brunet L, Moodie EE, Rollet K, Cooper C, Walmsley S, Potter M, Klein MB; Canadian Co-infection Cohort Investigators.
Department of Epidemiology, Biostatistics and Occupational Health, McGill University.