Smoking marijuana via electronic nicotine delivery systems has a higher association with lung damage symptoms when compared to smoking nicotine via similar electronic vapes or traditional cigarettes, according to a new University of Michigan study.
The study — conducted by Carol Boyd, co-director of the Center for the Study of Drugs, Alcohol, Smoking and Health and professor at the School of Nursing — was published in the Journal of Adolescent Health on March 3.
The exploratory study used pre-existing data from the Population Assessment of Tobacco and Health Study, a collaborative work between the National Institutes of Health and the Food and Drug Association. The study officially began in 2013 and examined how tobacco and various drugs impact adolescents ages 12 to 17.
Boyd and her team specifically looked at adolescents who were currently smoking cigarettes, vaping e-cigarettes or vaping marijuana and any association with “wheezing or whistling in the chest, sleep disturbed because of wheezing, speech limited because of wheezing, sounded wheezy during or after exercise and dry cough at night not associated with a cold or chest infection,” according to the study.
Boyd wrote in an email to The Michigan Daily that she anticipated e-cigarettes would have a stronger association with symptoms of respiratory problems. However, the results from the study took the researchers by surprise.
“What we found was (when) compared to adolescents who reported lifetime vaping cannabis, we found there was a notably weaker relationship between e-cigarette or cigarette use and respiratory symptoms (when compared to adolescents who had vaped cannabis),” Boyd wrote. “This surprised us, we thought we would find more negative respiratory symptoms in both cigarettes and e-cigarettes users.”
Adolescents who were categorized as lifetime cannabis vapers associated with all five of the negative respiratory systems observed within the data set. Vaping and smoking e-cigarettes were only associated with some negative symptoms, such as a dry cough at night not due to chest illness or infection.
Though all three forms of smoking examined in the study were associated with respiratory symptoms, Boyd wrote vaping cannabis produced the strongest negative relationship.
“Cigarette use (in the fully adjusted models) had significant associations with a dry cough at night that was not due to a cold or chest infection,” Boyd wrote. “If we simply look at e-cigarette use (with nicotine) and its simple relationship to respiratory symptoms, we see that e-cigarette use is associated with some symptoms, but what is important is that if we control for vaping cannabis, the association goes away.”
Philip Veliz, an associate research professor at the Nursing School’s Applied Biostatistics Laboratory, worked with Boyd on the publication. He said he hopes the study makes people more cautious when evaluating the consequences of inhaling various forms of drugs.
“Adolescents should have a better understanding of the negative consequences of using this drug, particularly if they are vaping it,” Veliz said. “We want adolescents to be informed about the risks with any type of drug use.”
Boyd said she hopes this study makes those with misconceptions about vaping more aware.
“Since many teens who vape nicotine also vape cannabis, I recommend everyone treat all vaping as a risky behavior,” Boyd wrote. “We know that inhaling hot tobacco/cannabis smoke into your lungs is unhealthy and can cause bronchitis or life-threatening breathing problems.”
Boyd also noted the importance of not extrapolating the results beyond the sample used by the study, which was limited to teenagers under 17.
“However, if individuals experience symptoms when they are adolescents, they are likely to experience them when they are older,” Boyd wrote.
Boyd highlighted several other limitations in the study, including that they were often unable to discern if participants solely vaped e-cigarettes or solely vaped cannabis, as these behaviors often go hand-in-hand.
Veliz said he believes similar studies should be conducted to keep the youth and general public educated regarding popular forms of drug usage. He also said an important future step would be to examine causal relationships between smoking and vaping and the negative effects, rather than only examining associations.
“We really want to see causal effects, which carry much more weight with respect to … the extent to which this type of substance impacts the development of adolescents’ lungs,” Veliz said.
Veliz also discussed the importance of researchers being transparent about drug use and its risks as people experiment with them, specifically for the student population on campus, where marijuana has become increasingly accessible.
“That spills over to the collegiate population as well,” Veliz said. “You should know the risks that are associated with this type of drug use. There has to be a meaningful dialogue. People are going to use it, some people will experiment with it. But, you should know the risks associated with it.”
When it comes to adolescents’ experimentation with vaping and becoming addicted to various drugs, LSA freshman Olivia Schafer — who plans to attend medical school — said she had seen the numerous effects of vaping and addiction when she was in high school.
“I feel it became a pretty big gag amongst users, and I remember people on sports teams joking about it impacting their lung capacities and endurances,” Schafer said.
Schafer also thinks a study like this could be misinterpreted, as it shows a weaker relationship between vaping ecigarettes and negative effects than with other forms of drug use, by adolescents and lead to increased vaping or smoking.
“Anything that makes vaping or e-cigarettes seem safer could encourage them to use it more,” Schafer said. “I think the idea that vaping is safer or cleaner than actual smoke, in general, negatively impacts adolescents.”
Daily Staff Reporter Nadir Al-Saidi can be reached at alsaidin@umich.edu.