Cannabis use did not reduce hepatitis C cure rates in patients on opioid substitution therapy

In a real-world registry of nearly 8,000 hepatitis C patients, cannabis use had no significant effect on cure rates (SVR) in either standard patients or those on opioid substitution therapy.

Christensen, Stefan et al.·Substance abuse : research and treatment·2019·Strong EvidenceProspective Cohort
RTHC-01985Prospective CohortStrong Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Prospective Cohort
Evidence
Strong Evidence
Sample
Not reported

What This Study Found

Cannabis use did not significantly influence SVR rates in either intention-to-treat or per-protocol analysis, regardless of opioid substitution therapy status. High alcohol consumption slightly reduced ITT cure rates (due to more lost-to-follow-up), but per-protocol rates were similar. OST patients had higher LTFU rates but similar per-protocol cure rates.

Key Numbers

739 OST patients, 7,008 non-OST. Non-OST/no drug use SVR: 91-92% (ITT). OST SVR: 83-86% (ITT). Difference mainly due to LTFU (11-12% vs 2-3%). Cannabis use: no significant effect on SVR in any analysis.

How They Did This

Analysis of the German Hepatitis C Registry (DHC-R), a national multicenter prospective real-world registry. 739 OST patients and 7,008 non-OST patients treated with direct-acting antivirals.

Why This Research Matters

Concerns about cannabis and alcohol use in hepatitis C patients on opioid substitution have led some clinicians to defer or deny treatment. This study shows these concerns are unfounded for cure rates.

The Bigger Picture

This large registry study removes a barrier to treating hepatitis C in substance-using populations. If cannabis and alcohol do not reduce cure rates, there is no pharmacological reason to withhold treatment from these patients.

What This Study Doesn't Tell Us

Self-reported substance use may be underestimated. Cannabis type and quantity not specified. LTFU after end of treatment could mask some treatment failures. German healthcare context may not generalize to all settings.

Questions This Raises

  • ?Should substance use screening be used to guide HCV treatment decisions?
  • ?Does cannabis affect treatment adherence even if it does not affect cure rates?
  • ?Would similar results be seen with other drug classes?

Trust & Context

Key Stat:
Cannabis: no effect on cure rates
Evidence Grade:
Rated strong because this is a large national registry with nearly 8,000 patients and prospective data collection.
Study Age:
Published in 2019.
Original Title:
Alcohol and Cannabis Consumption Does Not Diminish Cure Rates in a Real-World Cohort of Chronic Hepatitis C Virus Infected Patients on Opioid Substitution Therapy-Data From the German Hepatitis C-Registry (DHC-R).
Published In:
Substance abuse : research and treatment, 13, 1178221819835847 (2019)
Database ID:
RTHC-01985

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Enrolls participants and follows them forward in time.

What do these levels mean? →

Frequently Asked Questions

Does cannabis use affect hepatitis C treatment?

No. In this large German registry, cannabis use had no significant effect on cure rates for hepatitis C, whether patients were on opioid substitution therapy or not.

Should substance users be treated for hepatitis C?

This study supports treating substance-using patients. Cure rates were similar when controlling for treatment completion, and neither cannabis nor moderate alcohol use reduced effectiveness.

Read More on RethinkTHC

Cite This Study

RTHC-01985·https://rethinkthc.com/research/RTHC-01985

APA

Christensen, Stefan; Buggisch, Peter; Mauss, Stefan; Böker, Klaus Hw; Müller, Tobias; Klinker, Hartwig; Zimmermann, Tim; Serfert, Yvonne; Weber, Bernd; Reimer, Jens; Wedemeyer, Heiner. (2019). Alcohol and Cannabis Consumption Does Not Diminish Cure Rates in a Real-World Cohort of Chronic Hepatitis C Virus Infected Patients on Opioid Substitution Therapy-Data From the German Hepatitis C-Registry (DHC-R).. Substance abuse : research and treatment, 13, 1178221819835847. https://doi.org/10.1177/1178221819835847

MLA

Christensen, Stefan, et al. "Alcohol and Cannabis Consumption Does Not Diminish Cure Rates in a Real-World Cohort of Chronic Hepatitis C Virus Infected Patients on Opioid Substitution Therapy-Data From the German Hepatitis C-Registry (DHC-R).." Substance abuse : research and treatment, 2019. https://doi.org/10.1177/1178221819835847

RethinkTHC

RethinkTHC Research Database. "Alcohol and Cannabis Consumption Does Not Diminish Cure Rate..." RTHC-01985. Retrieved from https://rethinkthc.com/research/christensen-2019-alcohol-and-cannabis-consumption

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.