Smoking marijuana could be more harmful than people think, according to a new study.
Chest scans show that marijuana smokers are more likely to develop airway inflammation and some type of emphysema than people who puff on traditional cigarettes.
The Canadian researchers’ analysis, published Tuesday in Radiology, compared chest scans of marijuana smokers and tobacco-only smokers who were age-matched. They found that twice as many people who inhaled cannabinoids developed paraseptal emphysema as people who smoked only cigarettes.
Paraseptal emphysema is a disease of the small air sacs in the lungs that are responsible for taking in oxygen and removing carbon dioxide, said study co-author Dr. Giselle Revah, a cardiothoracic radiologist at The Ottawa Hospital.
“When damaged, little holes are created in the lungs and gas exchange doesn’t work as well,” she said.
The higher rate of paraseptal emphysema in marijuana smokers could be due to two factors, Revah suspects. Unlike cigarettes, joints are unfiltered and marijuana smokers inhale deeper and longer than cigarette smokers.
Although not as deadly as the more common type of emphysema linked to long-term heavy smoking, Paraseptal emphysema can lead to a number of distressing symptoms, said pulmonologist and longtime cannabis researcher Dr. Donald Tashkin of UCLA’s David Geffen School of Medicine.
Symptoms of emphysema include:
- Shortness of breath when climbing stairs.
- A feeling that a person cannot get enough air into the lungs.
- Persistent cough and wheezing.
- Coughing up mucus.
Paraseptal emphysema can sometimes lead to a collapsed lung, which can be life-threatening, Tashkin said.
No form of emphysema is curable.
To take a closer look at the impact of smoking marijuana on lung health, Revah and colleagues reviewed the medical records of 146 patients who had received a special type of x-ray called a CT scan.
Marijuana smokers were identified by searching Ottawa Hospital records, using the terms “marijuana” and “cannabis”. Next, Revah and her colleagues determined which of the marijuana smokers had undergone the chest CT scan.
They then looked for non-smokers and cigarette smokers who had received chest scans to compare them to marijuana smokers.
“The lungs were not designed for cigarette or marijuana smoke.”
Dr. Panagis Galiatsatos, Johns Hopkins
Of the 56 people who reported smoking marijuana, 28 provided information on the amount, which averaged 1.85 grams per day. Most marijuana smokers, 50 out of 56, said they also smoked tobacco.
Marijuana smokers ranged in age from 20 to 73, non-smokers from 19 to 75, and tobacco-only smokers from 50 to 71.
Overall, 75% of marijuana smokers in the analysis had some type of emphysema, compared to 5% of non-smokers and 67% of tobacco-only smokers. When researchers focused on patients in three groups with an average age of 60 (30 marijuana smokers, 33 tobacco-only smokers, and 29 non-smokers), they found that 57% of marijuana smokers had emphysema. paraseptal, compared to 24% of tobacco smokers. – only smokers.
Marijuana smokers also had higher rates of airway inflammation.
The results came as no surprise to Dr. Panagis Galiatsatos, a pulmonologist who is the director of the tobacco treatment clinic at Johns Hopkins Medicine.
“Chemicals and toxins that regularly enter the lungs will cause damage,” Galiatsatos said. “The lungs weren’t designed for cigarette or marijuana smoke.”
The research has limitations, including its small size, so it needs to be validated by a larger study, Galiatsatos said.
People need to understand “that any inhalation is bad for the lungs, whether it’s tobacco or marijuana smoke,” said Dr. Thomas McLaren, cardiothoracic radiologist and assistant professor of radiology and cardiology at Vanderbilt University Medical. Center.
If you’re going to consume cannabis, “it’s absolutely not the best way to do it,” McLaren said, adding that edibles are what’s suggested for cancer patients.
A previous UCLA study of people who smoke only marijuana found symptoms of chronic bronchitis and generalized pathological changes in the airways, Tashkin said.
“So smoking marijuana damages the central airways,” he said.
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