Teenagers who try electronic cigarettes are more likely to try tobacco cigarettes a year later compared with those who don’t use the devices, suggests a study published in Tobacco Control
on 25 January 2016.
A total of 2,338 teenagers in Hawaii (average age 14.7 years) were questioned about their tobacco cigarette or e-cigarette use and followed up a year later. Of those who had tried e-cigarettes but not tobacco cigarettes at the start of the study, 20% went on to try cigarettes a year later. In contrast, among teens who had neither smoked tobacco nor used e-cigarettes when they were first questioned, 6% went on to try tobacco cigarettes (adjusted odds ratio [OR] 2.87, 95% CI 2.03 to 4.05; P<0.0001).
However, less than 1% of the teens who had tried only e-cigarettes when first questioned became exclusively tobacco cigarette smokers; 19% were dual users. In comparison, 48% of the teens who had tried tobacco cigarettes and not e-cigarettes became exclusively tobacco cigarette smokers, with 31% becoming dual users.
The authors of the study suggest that public health policies should restrict adolescents’ access to e-cigarettes.
But Deborah Arnott, chief executive of Action on Smoking and Health, says it is not surprising that adolescents who have used e-cigarettes are also likely to try smoking cigarettes. “That’s not proof of causality,” she says. “More significantly, most young people who tried e-cigarettes did not go on to smoke, and youth smoking rates in Hawaii have fallen steadily.”
During the initial survey, 31% of the teens had tried e-cigarettes, rising to 38% a year later; in comparison 15% had smoked cigarettes rising to 21% a year later.
 Wills TA, Knight R, Sargent JD et al. Longitudinal study of e-cigarette use and onset of cigarette smoking among high school students in Hawaii. Tobacco Control. doi 10.1136/tobaccocontrol-2015-052705