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Fifty-two people have died, and more than 2,000 have been hospitalized this year because of lung injuries caused by vaping. The crisis has raised awareness about the larger problem of teen vaping. Now, while many of the worst cases have been linked to black market products that contain THC, new evidence suggests something more - that people who vape nicotine are more likely to get respiratory diseases, including chronic bronchitis and emphysema. NPR's Allison Aubrey reports.
ALLISON AUBREY, BYLINE: Early last year, one of the most comprehensive studies ever done pointed to evidence that teens who vape nicotine can experience increased coughing, wheezing and other short-term effects, such as asthma exacerbations. Now researchers are beginning to pin down the potential long-term risks. The new study finds that e-cigarettes are linked to an increased risk of chronic lung disease.
Stan Glantz, a professor of medicine at UC San Francisco, and his collaborators assessed data from a study of about 30,000 people, including smokers and people who vape.
STAN GLANTZ: We started out with people who didn't have any diagnosis of respiratory disease, and then we followed them forward in time for three years. And we said, is there an association between e-cigarette use and new respiratory disease?
AUBREY: During that time, people who used combustible products, such as cigarettes, had more than double the risk of being diagnosed with a respiratory disease, which is not surprising. But the more novel finding is that e-cigarettes had an independent effect. People in the study who only used e-cigarettes had about a 30% higher risk of developing chronic conditions, such as COPD, chronic bronchitis, emphysema or asthma. Glantz says the risks appear to be highest among adults who both vape and smoke, which often happens when people turn to vaping in an attempt to quit smoking but then aren't able to completely give up cigarettes.
GLANTZ: If you are a dual user - that is, if you're using cigarettes and e-cigarettes at the same time - these two risks multiply.
AUBREY: Given that e-cigarettes are relatively new, the long-term effects of vaping are just beginning to be understood, says Robert Tarran of the University of North Carolina, Chapel Hill. He says this study offers important evidence.
ROBERT TARRAN: I think it's fair to say that the new study adds to the body of evidence saying vaping e-cigarettes is harmful to the lungs.
AUBREY: It seems that e-cigarettes can harm the lungs in multiple ways. Vaping can lead to inflammation and tamp down immune defenses.
TARRAN: Vaping can do a lot to the lungs, so it can change inflammatory processes. And it actually seems to cause immunosuppression, so it leaves people more prone to infection.
AUBREY: He says it's not just the nicotine. There are other ingredients, including propylene glycol, glycerin and flavoring compounds, that may lead to harmful effects when heated and inhaled. Despite these risks, many argue that e-cigarettes still have a role to play in trying to help smokers reduce the risk of lung disease. Amy Fairchild is dean of the College of Public Health at The Ohio State University.
AMY FAIRCHILD: There is no question that vaping nicotine is not safe, but it is safer than inhaling burning tobacco.
AUBREY: This remains the key argument in favor of vaping - that it's less risky than smoking. But at a time when 1 in 4 high school seniors report vaping and are at risk of getting hooked on nicotine, the authors of the new paper argue the evidence pointing to the harms of e-cigarettes is starting to pile up.
Allison Aubrey, NPR News.
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