Study: Marijuana Use Linked to Increased Risk of Severe COVID-19

Researchers found that people who use cannabis may have a higher chance of developing severe COVID-19.

An electron microscope image shows SARS-CoV-2 (round gold objects), which causes COVID-19, emerging from cultured cells. NIAID via The Epoch Times

Researchers found that people who use cannabis may have a higher chance of developing severe COVID-19, according to a paper released Friday.

A study, published June 21 in the JAMA Network Open, looked at the health records of more than 72,000 people who were seen for COVID-19 at a health care system based in the Midwest in 2020 and 2021, or the first two years of the pandemic.

Usage of cannabis in any form “was significantly associated with increased risk of hospitalization,” the study concluded. Of the 72,000 people, who had an average age of 48.9 and who had COVID-19 during at least one health care visit, 9.7 percent had present-day marijuana use, while 13.4 percent were current smokers and 24.4 percent were former smokers.

Researchers found that individuals who used cannabis and contracted COVID-19 also needed intensive care more often “than were people with no such history,” said a news release from the Washington University School of Medicine in St. Louis, which conducted the study.

They noted that the “elevated risk of severe illness” from using cannabis “was on par with that from smoking” cigarettes, the release said.

People who currently smoked tobacco had a 72 percent greater risk of being hospitalized, while cannabis users had an 80 percent or higher risk of hospitalization. People who used marijuana in the previous year also had a 27 percent increased chance of being admitted to the intensive care unit than those who did not use marijuana, according to the study. Tobacco smokers had a 22 percent more likely chance of needing intensive care than nonsmokers, researchers found.

In terms of the mechanism, they said that smoking marijuana can injure lung tissue, making it more vulnerable to being infected, similar to how tobacco smoke interacts with the lungs. Meanwhile, cannabis is known to suppress the body’s immune system response, which could prevent it from dealing with viral illnesses—regardless of whether it is smoked or eaten, they said.

“We just don’t know whether edibles are safer,” study author Nicholas Griffith, a medical doctor and resident at Washington University, said in the release.

The people they evaluated were asked a question about whether they used cannabis in the last year, which “gave us enough information to establish that if you use cannabis, your health-care journey will be different,” he said. “But we can’t know how much cannabis you have to use, or whether it makes a difference whether you smoke it or eat edibles.”

Authors of the study stated in the release that their results might contradict claims that cannabis can help fight off infections such as COVID-19.

Another study author, Li-Shiun Chen, said that “there hasn’t been as much research on the health effects of cannabis as compared to tobacco or alcohol,” but “what we found is that cannabis use is not harmless in the context of COVID-19.”

Earlier this year, a study produced by Dalhousie University in Nova Scotia, Canada found that “cannabinoids have the potential to be used as a preventive approach to limiting the susceptibility and severity of COVID-19 infections” because they block the virus’s entry into the body as well as “alleviating the associated cytokine storm” with the virus.

They also wrote that cannabis could also help with so-called “long COVID,” or symptoms that last long after an acute viral infection ends. “Cannabinoids have shown promise in treating symptoms associated with post-acute long COVID-19, including depression, anxiety, post-traumatic stress injury, insomnia, pain, and decreased appetite,” the researchers also said.

This research comes as an increasing number of states and municipalities across the United States have moved to legalize marijuana. As of April, about 24 states have made recreational cannabis use legal, including ones with large populations including California, New York, and Ohio, according to the Pew Research Center.

A poll from YouGov, released in April, found that 64 percent of Americans believe regular alcohol use is more harmful to an individual’s health than regular marijuana use, while 63 percent believe regular tobacco usage is more harmful than regular marijuana usage. It also found that one in four Americans said they used marijuana at least once in the past year.