Chest CT shows increased rates of emphysema in marijuana smokers compared with nonsmokers and tobacco smokers, according to research to be presented at the upcoming virtual American Roentgen Ray Society (ARRS) meeting.
The researchers led by Dr. Luke Murtha of Ottawa Hospital in Canada also found that marijuana smokers have greater rates of paraseptal emphysema.
"Marijuana smoking is also associated with airways disease, including bronchial wall thickening, bronchiectasis, and bronchiolar mucoid impaction, in comparison to both the control group and tobacco-only group," Murtha said in a statement released by the ARRS.
The investigators gathered data from Ottawa Hospital's PACS to create three groups of patients matched for age and sex: marijuana smokers (56), nonsmokers/nonmarijuana users (57), and tobacco-only smokers (33). Two radiologists blinded to smoking history read each patient's chest CT.
Murtha's group found the following:
- The rate of emphysema among marijuana-smoking patients was 75%, compared with 5% of the nonsmoking group.
- The increase of emphysema was 93% among marijuana smokers, compared with 66% of tobacco smokers.
- The proportion of paraseptal emphysema was 53% among marijuana smokers, compared with 24% among tobacco-only smokers and 7% among nonsmokers.
"Given that marijuana use is increasing, particularly within nations such as Canada, that have legalized the substance, it is important for us, as radiologists, to define specific findings associated with its consumption," Murtha's team concluded.
