Previously tobacco-naive children aged 12 to 15 years who have used e-cigarettes are at increased risk for later cigarette use, according to study results published in JAMA Network Open.
Researchers examined ever and current cigarette use as the primary outcome in children who were enrolled in the prospective Population Assessment of Tobacco and Health (PATH) Study. PATH used a 4-stage, stratified probability sample design with 3 waves. The risk of being initiated to smoking cigarettes was compared between those who had started using e-cigarettes and those who had not within a 2-year follow-up.
Of the 6123 study participants who were tobacco-naive at the start of the study, 8.6% reported e-cigarettes as their first tobacco product and 5.0% reported using another noncigarette product first; 3.3% reported using cigarettes first by wave 3. Compared with children who had no prior tobacco use, cigarette use was higher in those who had prior e-cigarette at wave 3 (20.5% vs 3.8%, respectively).
Previous use of e-cigarettes was linked to an increased risk of ever smoking cigarettes (odds ratio [OR], 4.09; 95% CI, 2.97-5.63), as well as current cigarette use (OR, 2.75; 95% CI, 1.60-4.73), compared with no previous tobacco use. Similarly, previous use of other tobacco products was associated with later cigarette smoking (OR, 3.84; 95% CI, 2.63-5.63), as well as current cigarette use (OR, 3.43; 95% CI, 1.88-6.26), compared with no previous tobacco use.
Furthermore, the association of prior e-cigarette use with cigarette initiation was stronger in children who were considered low risk (OR, 8.57; 95% CI, 3.87-18.97) compared with those considered intermediate or high risk (OR, 3.51; 95% CI, 2.52-4.89; P for interaction =.02). Low risk was defined as not displaying sensation-seeking personality traits or having any cigarette susceptibility.
This study does have several limitations. First, PATH data are observational, which means the researchers could not determine causal relations or rule out residual confounding. In addition, the study design relied on participant recall to develop tobacco use timelines and did not allow the researchers analyze whether the association of e-cigarette use with cigarette initiation varied by e-cigarette product characteristics or patterns of use.
This large, nationally representative study of US youths supports the view that e-cigarettes represent a catalyst for cigarette initiation among youths,” the researchers wrote. “The association was especially pronounced in low-risk youths, raising concerns that e-cigarettes may renormalize smoking behaviors and erode decades of progress in reducing smoking among youths.”
Berry KM, Fetterman JL, Benjamin EJ, et al. Association of electronic cigarette use with subsequent initiation of tobacco cigarettes in US youths. JAMA Netw Open. 2019;2(2):e187794.