People with a genetic predisposition to cannabis use disorder (CUD) are more likely to require hospitalization after contracting COVID-19 than people without the disorder. The study was published in Biological Psychiatry Global Open Science by researchers from Washington University and the University of Colorado Boulder.
Conditions including diabetes, obesity, and a history of smoking cigarettes are known risk factors towards worse outcomes following COVID-19 infection. New research now suggests that CUD is also a risk factor for adverse outcomes, or being hospitalized with the disease.
For the study, the researchers examined multiple data sets to investigate whether a higher genetic risk of cannabis use disorder was linked to adverse outcomes from COVID-19 infection. One dataset involved 357, 806 people, including 14,080 with CUD. Another involved over 1.2 million people, including 8,373 who were hospitalized with COVID.
The researchers also examined 7 million genetic variants and their links to both CUD and severe COVID.
From their analysis, the researchers found that genetic predisposition for CUD accounted for up to 40% of genetically influenced risk factors for severe COVID-19 outcomes. They noted that the genetic risk factor was similar to that for having a high body mass index (BMI), an already well-known risk factor for severe COVID-19 outcomes.
They further noted that the link was independent of other risk factors that determine a severe outcome to COVID-10, including metabolic traits like fasting glucose, respiratory traits like COPD, socioeconomic status, and lifestyle factors.
While the researchers do not know exactly what is behind the link, they say it could be due to one of two reasons. The first is that CUD and severe COVID-19 outcomes share a biological mechanism. The second is that there is a causal relationship between the two.
The researchers say that their results should be incorporated into strategies to combat the disease. They also say their results suggest that, just as quitting tobacco smoking or reducing BMI may protect against severe COVID-19 outcomes, stopping or reducing heavy cannabis use may protect against severe outcomes as well.