As the COVID-19 pandemic emerged, identifying risk factors for severe illness became crucial.
Factors like age, smoking history, high BMI, and pre-existing conditions were recognized early on as making individuals more vulnerable. However, the impact of cannabis use remained uncertain. Recent research has shed light on both protective and harmful effects of cannabis.
A new study from Washington University School of Medicine in St. Louis reveals a concerning finding: cannabis use is associated with an increased risk of severe COVID-19 illness.
This study, published in JAMA Network Open, analyzed health records of 72,501 individuals with COVID-19 in a Midwestern healthcare system over the first two years of the pandemic. Those who reported cannabis use in the year before contracting COVID-19 were more likely to require hospitalization and intensive care compared to non-users. This risk was comparable to that of smoking.
“The notion that cannabis is harmless is common, but our research shows it can have serious health implications in the context of COVID-19,” said senior author Li-Shiun Chen, MD. “Those using cannabis were more likely to need hospitalization and intensive care.”
Unlike smoking, cannabis did not show a significant increase in COVID-19 mortality rates. Issues related to hospitalization and intensive care were similar between cannabis and tobacco use.
The study utilized deidentified health records from BJC HealthCare between Feb. 2020 and Jan. 2022, considering various factors like demographics, health conditions, and substance use to draw its conclusions.
Cannabis users with COVID-19 were 80% more likely to be hospitalized and 27% more likely to require ICU admission compared to non-users. Tobacco smokers faced a 72% higher hospitalization risk and a 22% higher ICU admission risk than non-smokers.
Contrary to some studies suggesting benefits of cannabis in fighting viral infections, this research indicates otherwise.
“Prior evidence on cannabis benefits largely comes from lab studies, but our research leverages real-world data from COVID-19 patients across multiple sites and time periods,” noted Chen. “Our findings on smoking’s effects validate the reliability of our data.”
The study did not pinpoint why cannabis might exacerbate COVID-19 outcomes, speculating that lung damage from smoking or immune system suppression could play a role.
Questions about the safety of edibles versus smoking cannabis remain unanswered. More research on cannabis’s health effects is needed to better understand its impact.
“Exploring the impacts of cannabis consumption depth and method is crucial for future studies,” said lead author Nicholas Griffith, MD. “Our study signals the need for further research in this area.”
