Cannabis smokers may be more susceptible to emphysema than cigarette smokers, according to a study published in Radiology. Emphysema is a lung disease characterized by difficulty with breathing. The researchers believe that the answers lie in examining the differences in how cannabis and tobacco products are smoked. Cannabis smoke enters the lungs unfiltered when using a bowl, pipe, or joint, whereas cigarettes tend to have a more efficient built-in filter to reduce particulates that reach the lungs.
Although there is a vast body of research on the dangers of tobacco, this study is one of the first to explore respiratory risks associated with cannabis. The researchers compared chest CT results from 56 marijuana smokers with those of 57 non-smoking controls and 33 tobacco-only smokers. 75% of cannabis smokers had emphysema, while 67% of tobacco smokers had this lung disease, and 5% of the non-smokers had emphysema.
One finding indicated that paraseptal emphysema (PSE) was the predominant emphysema subtype in cannabis smokers compared to tobacco-only smokers. Paraseptal emphysema damages small ducts that connect to the lung's air sacs and causes wheezing and shortness of breath, among other symptoms.
Cannabis smokers also had higher rates of airway inflammation and enlarged male breast tissue (gynecomastia) due to a hormone imbalance than non-smokers and tobacco-only smokers. Gynecomastia was found in 38% of the cannabis smokers, compared with 11% of the tobacco-only smokers and 16% of the controls.
The researchers observed similar results among age-matched subgroups; airway inflammation was higher in cannabis smokers than tobacco smokers. However, there was no difference in coronary artery calcification between age-matched cannabis and tobacco-only groups. These findings suggest a future research agenda for the team. Study author Dr. Giselle Revah explained, “The fact that our marijuana smokers—some of whom also smoked tobacco—had additional findings of airway inflammation/chronic bronchitis suggests that marijuana has additional synergistic effects on the lungs above tobacco.” The study provides a solid foundation for further research on lung disease associated with cannabis use.
Sources: Eureka News Alert, Radiology