People genetically predisposed to problematic cannabis use may also have higher odds of requiring hospitalization after contracting COVID-19, according to new research. Appearing in the journal Biological Psychiatry Global Open Science, the study does not imply that smoking weed causes more severe symptoms, but does provide valuable new insights into the genetic risk factors associated with the virus.
Understanding risk factors that contribute to poorer COVID-19 outcomes allows public health officials to identify and protect certain vulnerable populations. Previous investigations revealed that those with a high genetic susceptibility to diabetes, obesity, and hypertension are all at increased risk, and medics are therefore extra vigilant when monitoring patients with these characteristics.
According to the study authors, cannabinoid signaling is known to play a role in regulating immune responses. That being the case, they investigated whether a connection exists between cannabis use disorder (CUD) and severe COVID-19 symptoms.
“If we know the genes that predispose individuals to cannabis use disorder, and if cannabis use disorder is a risk factor for COVID-19 hospitalization, you will see the genes influencing cannabis use disorder as predictors of severe COVID-19 cases,” explained study author Alexander Hatoum in a statement.
Characterized by a persistent desire to consume cannabis and an inability to decrease use, CUD is triggered by an assortment of genetic and environmental factors. To determine genetic risk factors associated with the condition, the study authors examined the genomes of 343,726 people, of which 14,080 had been diagnosed with CUD.
They then cross-referenced their findings with data from the COVID-19 Host Genetics Initiative, which includes the genomes of 1,197,256 people who have been infected by the virus. Of these, 9,373 required hospitalization.
“Our findings suggest that genetic liability to CUD is correlated with risk for COVID-19 hospitalization,” write the study authors. Overall, the researchers looked at around 7 million genetic variants and estimated that those associated with CUD could contribute 38 percent of the genetic risk factors for severe COVID-19 symptoms.
It’s important to note that not everyone who possesses some or all of these genetic variants will develop CUD, which means heavy cannabis use per se cannot be linked to poorer outcomes in infected individuals. Furthermore, the researchers state that it is unclear whether their findings suggest that CUD causes severe COVID-19 symptoms or if the two are simply the result of a common biological mechanism.
“While such findings suggest that it is plausible that CUD may have an independent causal impact on severe COVID-19 outcomes, genomic causal models […] did not support a causal role of CUD on COVID-19 hospitalization,” they write.
Nevertheless, Hatoum says that this research “raises the intriguing possibility that heavy and problematic cannabis use may contribute to severe COVID-19 presentations.”
“As such, it is possible that combating heavy and problematic cannabis use may help mitigate the impact of COVID-19.”