Cannabis Use Did Not Affect Immune Cell Counts in HIV-Hepatitis C Co-Infected Patients | Research

The takeaway

Among 955 HIV-HCV co-infected patients on antiretroviral therapy, cannabis use showed no significant effect on CD4 T-cell counts or percentages, providing reassurance for immunocompromised patients who use cannabis.

Read this if you are living with HIV or hepatitis C and use cannabis, and want to know whether it affects your immune system.

No effect of cannabis on CD4 T-cell counts in 955 HIV-HCV co-infected patients

What the researchers found

This large longitudinal study examined whether cannabis use affects the most important immune marker in HIV management, the CD4 T-cell count, in patients co-infected with both HIV and hepatitis C.

Among 955 patients followed over multiple visits (2,386 total visits), cannabis use was remarkably common: 48% reported use in the preceding four weeks. Of cannabis users, 58% also smoked 10 or more tobacco cigarettes daily.

After multiple statistical adjustments, cannabis use was not significantly associated with either CD4 T-cell count or CD4 T-cell percentage. Sensitivity analyses excluding tobacco users and heavy smokers confirmed the null finding.

This is clinically important because HIV-HCV co-infected patients often use cannabis for symptom management, and concerns about immunosuppression could theoretically limit its use in this already immunocompromised population.

Why it matters

HIV-HCV co-infected patients already face compromised immune function. If cannabis further reduced CD4 counts, it could accelerate disease progression. This study provides evidence-based reassurance that cannabis use does not measurably harm this critical immune parameter.

The numbers in context

955 patients, 2,386 visits. 48% reported cannabis use. Cannabis use coefficient for CD4 count: 0.27 (95% CI -0.07 to 0.62, p=0.12). Cannabis use coefficient for CD4 percentage: -0.04 (95% CI -0.45 to 0.36, p=0.83).

How the study worked

Longitudinal analysis of the ANRS CO13-HEPAVIH French cohort. Cannabis use assessed via annual self-administered questionnaires in 955 patients (2,386 visits). CD4 T-cell count and percentage analyzed using multivariate linear regression with generalized estimating equations. Sensitivity analyses excluded tobacco users.

What this study cannot tell us

CD4 count and percentage are crude measures of immune function that do not capture cell functionality. Self-reported cannabis use may be inaccurate. The study did not assess cannabis dose, type, or administration route. All patients were on antiretroviral therapy, which itself maintains CD4 counts.

How to read the evidence

Large longitudinal cohort with multiple visits and statistical adjustments. Moderate because of comprehensive methodology despite self-reported cannabis use and limited immune markers.

When this study was published

Published in 2017.

The bigger picture

While this study is reassuring about circulating CD4 counts, the authors note that cannabis could affect immune cells in other locations (like the lungs) or affect cell function without changing counts. The overall finding supports cannabis as relatively safe from an immune standpoint in this population.

Questions still open

Does cannabis affect CD4 cell function (ability to fight infections) even if counts remain stable? Are there effects on other immune cells (CD8, NK cells) not measured in this study? Would cannabis interact with specific antiretroviral medications?

Common questions

Does cannabis weaken the immune system in HIV patients?

This study found no evidence that cannabis use affected CD4 T-cell counts or percentages in 955 HIV-HCV co-infected patients on treatment. This provides reassurance, though other aspects of immune function were not measured.

Is cannabis safe for people with HIV?

From the standpoint of CD4 counts (the most important immune marker in HIV management), this study found no negative effect of cannabis. Nearly half of patients used cannabis, suggesting its use is common and not associated with immune deterioration in this context.

Read the original research

No significant effect of cannabis use on the count and percentage of circulating CD4 T-cells in HIV-HCV co-infected patients (ANRS CO13-HEPAVIH French cohort).

Drug and alcohol review, 36(2), 227-238

View on PubMed ↗Publisher’s paper ↗

Citation

Marcellin, Fabienne; Lions, Caroline; Rosenthal, Eric; Roux, Perrine; Sogni, Philippe; Wittkop, Linda; Protopopescu, Camelia; Spire, Bruno; Salmon-Ceron, Dominique; Dabis, François; Carrieri, Maria Patrizia. (2017). No significant effect of cannabis use on the count and percentage of circulating CD4 T-cells in HIV-HCV co-infected patients (ANRS CO13-HEPAVIH French cohort).. Drug and alcohol review, 36(2), 227-238. https://doi.org/10.1111/dar.12398