A scan of the lungs of cannabis users yielded surprising results. marijuana There appears to be a higher risk of lung damage than in solo smokers.
“There is a general perception that marijuana is safe,” said Gisele Reba, M.D., a radiologist at the University of Ottawa in Ontario, Canada. increase.”
Revah said CT scans can often quickly tell if someone is a heavy or long-time cigarette smoker.However, with legalization and increasing use of marijuana Canada and many US statesshe began to wonder what effects cannabis use had on her lungs, and whether those effects could be distinguished from those of smoking.
she and her colleague examined retrospectively Chest CT scans of 56 marijuana smokers were compared with scans of 57 nonsmokers and 33 tobacco-only users.
emphysema It was significantly higher in marijuana smokers (75%) than in nonsmokers (5%). When matched for age and sex, 93% of marijuana smokers had emphysema, compared with 67% of those who smoked only cigarettes (P. = .009).
When age-matched, the incidence of emphysema remained slightly higher among marijuana users (75% vs. 67%), but the difference was no longer statistically significant. However, more than 40% of him in the marijuana group were under his 50s, and all tobacco-only users were over 50s. This means that marijuana smokers may have earlier or lesser exposure to lung damage.
Revah added that her colleagues in family medicine say the findings match their clinical experience. “In their practice, we have a young patient with emphysema,” she said.
Marijuana smokers also showed higher rates of airway inflammation, including bronchial thickening. bronchiectasisand mucoid impaction were found by researchers with and without gender and age matching.
According to Alan Kaplan, M.D., an Ontario family physician who specializes in respiratory health, the findings are “not at all surprising.” 2021 review About cannabis and lung health.
and Editorial companion According to a journal article, pulmonary experts say new data support the recent increase in referrals for non-traumatic pneumothorax. The authors say that in the past two years he has received 22 referrals, but from 2012 to 2020 he has received only six.
One reason for the additional damage could be the way marijuana is inhaled, Kaplan said. Marijuana smokers “when you take a deep breath, you’re actually pushing it into your lungs, creating pressure, which can actually cause your alveoli to expand over time.”
Most marijuana smokers in the study also smoked cigarettes, so it is impossible to discern whether the observed damage was caused by marijuana alone or in synergy with tobacco. .
Still, the results are surprising, she said, because the marijuana group was compared to smokers who had smoked for 25 to 100 years and had undergone a high-risk lung cancer screening program.
Revah and her colleagues are now conducting a larger, prospective study to see if they can confirm their findings.
“The message to doctors is to ask about smoking cannabis,” Kaplan said. Until now, people have been reluctant to admit to using cannabis. Even if it were legalized, they may be slow to tell their doctors. But clinicians should still try to identify frequent users, especially those with a predisposition to lung disease. He said the advice should be, “There are safer ways to use cannabis” if you intend to use the drug.
Revah and Kaplan have not disclosed any related financial relationships.
Donavyn Coffey is a Kentucky-based journalist who covers healthcare, the environment, and everything that impacts what we eat. She holds her Master’s degree from NYU’s Arthur L. Carter Journalism Institute and a Master’s degree in Molecular Nutrition from Aarhus University, Denmark. You can see more of her work in Wired, Scientific American, Popular Science, and more.