Inhaling heated tobacco vapour through e-cigarettes may lead to increased chances of asthma and chronic lung disease, according to a study which cautioned that vaping may lead to a rise in nicotine addiction among the youth if public health education on its harmfulness is not intensified.
The researchers, including those from Johns Hopkins University in the US, said the odds of developing chronic obstructive pulmonary disease (COPD) were six times greater among people who reported they both vaped and smoked tobacco regularly, compared with those who said they didn't use either.
While e-cigarettes may be safer than combustible cigarettes, the study, published in the American Journal of Preventative Medicine, adds to growing evidence that vaping also carries health risks.
As part of the study, the scientists used the US Centers for Disease Control and Prevention's national survey data gathered by the Behavioral Risk Factor Surveillance System from 2016 and 2017.
It consisted of telephone interviews of more than 4,00,000 adult participants and provides data on health-related risk behaviours, and chronic medical conditions.
The researchers analysed data from those who said they had smoked less than 100 combustible cigarettes in their lifetimes.
Of these, about 3,100 reported using e-cigarettes, and separately 34,074 people reported having asthma.
According to the researchers, the average age of e-cigarette users was 18-24, and about two-thirds of all the e-cigarette users were men.
Approximately 57 per cent of the users reported they were white, and about a fifth were Hispanic, and 12 per cent were black.
Almost 11 per cent of the e-cigarette users reported having asthma, compared with 8 per cent of those who had never used e-cigarettes.
Those who said they were currently using e-cigarettes were nearly 40 per cent more likely to report having asthma compared to those who said they'd never used vapes.
Participants who self-reported using e-cigarettes occasionally were 31 per cent more likely, and daily users were nearly 73 per cent more likely to report asthma, compared with non-e-cigarette users.
"As a physician, I am most worried about those who use both e-cigarettes and combustible cigarettes because they may end up taking in the most nicotine, which may do the most damage," said Albert Osei study co-author form Johns Hopkins University.
"Through public health campaigns, we finally had smoking levels down in some populations, but now with the current vaping epidemic, I foresee a whole new previously tobacco-naive, young generation becoming dependent on nicotine if we do not intensify public health education efforts," Osei added.