The study further underscores concerns that e-cigarettes are acting as entry nicotine products that may lead to the use of more harmful and toxic nicotine products, such as combustible cigarettes. Using both e-cigarettes and cigarettes at the same time — called dual use — is a common use pattern among youth. In 2015,
65 percent of youth
who had used an e-cigarette in the last 30 days also reported using another tobacco product in the same time frame.
The study, published in
Nicotine & Tobacco Research
, used data from a group of 16- to 20- year-olds in California to examine patterns of e-cigarette and cigarette use as they transitioned into young adulthood. More than 2,000 young people completed three surveys over a three-year period from 2015 to 2017. Researchers found “significant, reciprocal associations between [e-cigarette] and cigarette use.”
The data show that more frequent e-cigarette use at one point in time during the study predicted more frequent cigarette use at a later time during the study, and vice versa. The data also suggest that “young people who use both e-cigarettes and cigarettes may progress toward heavier use of both products over time,” instead of switching from e-cigarettes to cigarettes or substituting e-cigarettes for cigarettes.
The Food and Drug Administration recently announced that
youth e-cigarette use has reached “epidemic proportions,”
which is reigniting concerns not only about future combustible tobacco use, but also nicotine addiction in youth. Early nicotine addiction can harm brain development and alter nerve cell functioning. Nicotine may also alter brain chemistry in ways that make adolescent brains more susceptible to other addictive drugs. The earlier someone is exposed to nicotine in adolescence, the harder it is to quit.
“Progression toward more frequent use of [e-cigarettes] and cigarettes over time could increase total nicotine consumption and risk of nicotine dependence and associated harms as adolescents transition into young adulthood,” researchers wrote. “Thus, efforts to prevent and reduce [e-cigarette] use among young people (e.g., through informational campaigns, enacting and enforcing policies to limit youth access to [e-cigarettes]) may help to reduce use of more harmful tobacco products.”