A new study has found that youngsters who use e-cigarettes are less likely to use cigarettes in the future compared to those who use other tobacco products. The researchers called this the “gateway effect” – moving on the full-fledged smoking and say it is small among those who use e-cigarettes to start with.
The study titled, “Association of initial e-cigarette and other tobacco product use with subsequent cigarette smoking in adolescents: a cross-sectional, matched control study,” was published in the latest issue of the journal Tobacco Control.
This study assessed whether initiating e-cigarette use increases the uptake of cigarette smoking in US adolescents compared with behavioral and synthetic controls. Image Credit: NeydtStock / Shutterstock
What this study was about?
There have been studies about the harmful effects of youngsters vaping or using e-cigarettes. There is also evidence that the use of e-cigarettes could be one of the best possible ways for smokers to quit smoking. The researchers wrote that many studies are looking at the number of teenagers taking up vaping but none following them up to see if they become smokers in the future.
This study was conducted to see if the initiation of e-cigarettes among the youth increased the uptake of traditional cigarette smoking later in life among teenagers of the United States. The use of e-cigarettes was compared with “behavioral and synthetic controls,” wrote the researchers.
What was done?
The study was part of the National Youth Tobacco Survey conducted between 2014 and 2017. In this study, a total of 78,265 adolescents were included. Among these teenagers, a total of 38 630 answered questions regarding the first tobacco-containing products they used in 2014 and 2015. Those using e-cigarettes for the first time were called the exposure group while the rest were called “non-cigarette combustible (CT)” group and “other non-combustible tobacco (NT)” group. These were the behavioral controls. Those who did not use e-cigarettes at the start were the “synthetic controls.”
Those who had ever tried a puff or two were classified as “ever smokers” while those who had smoked at least a single cigarette in the past 30 days were classified there. Those who smoked over 100 cigarettes were classified as established smokers. Combustible tobacco products included cigars, hookahs, pipes, or cigarillos. Non-combustible tobacco products included chewing tobacco and snuff etc.
After that the team of researchers compared 30-day use of cigarettes and a 100 plus lifetime of cigarettes used among the groups. They also derived a propensity score from seeing synthetic controls and exposure groups take up smoking in the future.
The researchers noted that more girls were open to try new products and with age the propensity to experiment with products rose in both genders with age. The study revealed that compared to behavioral controls (non-cigarette combustible), those using e-cigarettes first were less likely ever to smoke cigarettes by 26 percent. Those smoking other non-combustible tobacco products were at a 52.7 percent greater risk of smoking in the future. Less than 1 percent of teenagers who tried e-cigarettes first went on to become smokers later, they noted. For those using non-cigarette combustible products, the conversion rate to smoking was 9 percent, and those using non-combustible products for the first time the conversion to smoking was 16 percent. The conversion rate to smoking was 2.7 percent among first-time e-cigarette users, they found. E-cigarette initiators were also at a lower risk of ever having smoked a cigarette, be a smoker in the last 30 days or turn into established smokers compared to synthetic controls, found the researchers.
The team wrote, “…the association of subsequent use of e-cigarettes was stronger for adolescents initiating with cigarettes than the association of subsequent cigarette smoking for e-cigarette initiators.” They added, “This underlines the fact that cigarettes act as a much more important gateway for any product use.”
Implications and conclusions
The researchers concluded that “over the time period considered, e-cigarettes were unlikely to have acted as an important gateway towards cigarette smoking and may, in fact, have acted as a gateway away from smoking for vulnerable adolescents; this is consistent with the decrease in youth cigarette smoking prevalence over the same time period that youth e-cigarette use increased between 2014 and 2017.” They added, “Our results explain the seemingly opposing observations that e-cigarette use is associated longitudinally with a greater likelihood of starting to smoke cigarettes and that youth cigarette smoking rates have continued to fall over the last decade in countries which have seen an increase in e-cigarette use by adolescents, both in the USA and elsewhere.”
Cancer Research UK funded this project.
Shahab L, Beard E, Brown J, Association of initial e-cigarette and other tobacco product use with subsequent cigarette smoking in adolescents: a cross-sectional, matched control studyTobacco Control Published Online First: 17 March 2020. doi: 10.1136/tobaccocontrol-2019-055283