PITTSBURG, Pennysylvania (REUTERS) - Teenagers and young adults who use e-cigarettes are more likely to move on to traditional cigarettes than those who do not use the electronic devices, according to a small study sponsored by the National Cancer Institute.
The study, by researchers at the University of Pittsburgh and Dartmouth-Hitchcock Norris Cotton Cancer Centre, followed 694 people aged 16 to 26 who said they definitely had no intention of smoking cigarettes. Of those, 16 people, or 2.3 per cent, were using e-cigarettes.
After one year, six of the e-cigarette users, or 37.5 per cent, had begun smoking compared with 65, or 9.6 per cent of those who were not using e-cigarettes at the start of the trial.
Another five e-cigarette users, or 31.3 per cent, were no longer certain that they would not smoke cigarettes compared to 63, or 9.3 per cent, of those who were not using e-cigarettes at the beginning.
A significant limitation of the study was the relatively small number of people who were using e-cigarettes at the beginning of the trial, making it difficult to be confident that the results would be replicated in a larger e-cigarette user sample.
The study, which was published online on Tuesday and is scheduled for publication in the November edition of the journal JAMA Pediatrics, is one of dozens of research projects seeking to shed light on whether e-cigarettes are a net boon to society or a net negative.
The US Food and Drug Administration is weighing how heavily to regulate the products, which some argue could dramatically cut the rate of disease in traditional smokers if they were to switch to e-cigarettes.
Public health advocates fear they could introduce a new generation of young people to nicotine and, potentially, act as a gateway to cigarettes.
The latest study did not address whether the six e-cigarette users who had transitioned to smoking were smoking on a routine basis, whether they were using both e-cigarettes and cigarettes, or simply experimenting.
The authors attempted to adjust for variables that could have accounted for the progression of some e-cigarette users to smoking. The study found that people who were using e-cigarettes at the start of the study were more likely to engage in sensation-seeking behaviour, and may have been more likely to take up smoking anyway.
But even adjusting for sensation-seeking tendencies, the association between e-cigarette use and progression towards smoking remained, the authors found.
"It will be important to continue surveillance among youth of both e-cigarette use and overlap with use of other tobacco products," they wrote.