Study suggests cannabis may lessen severity of Covid-19 symptoms

Interest in the potential of cannabis and cannabinoids, to prevent or lessen the severity of Covid-19 symptoms, is growing.

Cannabis and its impact on patients with Covid-19 are becoming the subject of an ever-growing body of scientific research, with a number of studies investigating its immunomodulatory and anti-inflammatory effects.

In January this year, researchers at the University of Chicago found that CBD showed a significant negative association with SARS-CoV-2 positive tests, in a national sample of patients who were taking high doses of CBD prescribed for epilepsy.

Another study found that high-CBD Cannabis sativa extracts could be used to reduce the expression of ACE2, a protein that acts as the receptor for Covid-19 in cells on the tongue and oral mucosa.

The latest paper to explore cannabis and its COVID-fighting potential was published last month in the Journal of Cannabis Research and found an association between cannabis consumption and less severe symptoms among hospitalised patients.

The paper follows a study led by the same lead researcher, Richard von Breedan of Oregon State University, which found that cannabigerol acid (CBGa) and cannabidiolic acid (CBDA) could have the potential to prevent the SARS-CoV-2 from entering human cells.

The retrospective analysis examined 1,831 Covid-19 patients admitted to two hospitals in California, 69 of which reported being active cannabis users.

The researchers noted that cannabis consumers entered hospital with lower levels of inflammation than non-users and had “significantly better” outcomes, which were reflected in lower NIH scores, shorter hospitalisation, lower ICU admission rates and less need for mechanical ventilation.

The researchers behind the study said: “To our knowledge, this study is one of the first evaluations of the effect of cannabis use on outcomes in patients hospitalised with Covid-19.

“While previous data have determined the detrimental relationship of tobacco smoking with Covid-19, this study suggests that cannabis may actually lead to reduced disease severity and better outcomes despite a five-fold greater concomitant use of tobacco amongst cannabis users compared to non-users in our study population.”

The researchers noted that cannabis users were significantly younger than other patients and were five times more likely to smoke tobacco, the latter of which is thought to have “detrimental” effects on Covid-19 patient outcomes.

Despite this, the researchers found that cannabis users still experienced less severe symptoms, even when results were adjusted for age, tobacco use and co-morbid conditions.

“When adjusting for age these outcomes remained consistent,” the researchers wrote in the paper’s discussion.

“Even more, when adjusting for co-morbid conditions, demographics and smoking history we found that cannabis users still had less severe disease progression compared to non-users.”

While the trend was clear, researchers noted in the paper’s conclusion that the correlation was not “statistically significant”.

They added: “This retrospective cohort study suggests that active cannabis users hospitalised with Covid-19 had better clinical outcomes compared with non-users, including decreased need for ICU admission or mechanical ventilation.

“However, our results need to be interpreted with caution given the limitations of a retrospective analysis. Prospective and observational studies will better elucidate the effects cannabis use in Covid-19 patients.”

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