[The Course of E-Cigarette Use in Adolescence: A Cohort Study over 18 Months]

Description of adolescent e-cigarette use over time.

In 2017 and 2019, 261 adolescents from North Rhine-Westphalia who had used e-cigarettes at least once a month (mean age: 14.9 years; 33.5 % female) took part in a questionnaire study.

In 2017, 84 adolescents (32.2 %) reported exclusive e-cigarette use (single users), 177 adolescents were classified as dual users (67.8 %) because they consumed a tobacco product (conventional cigarette and/or hookah) in addition to e-cigarettes. During the observation period of 18 months, 83 adolescents (31.8 %) quit nicotine products altogether. Dual users quit nicotine less often than single users (N = 39 or 22.0 % vs. N = 44 or 52.4 %, p < 0.001). Seven single users (8.3 %) did not change their behavior, 11 began to use tobacco exclusively (13.1 %), another 22 (26.2 %) started dual use. Seventy-eight dual users (44.1 %) did not change their behavior, 57 (32.1 %) switched to tobacco use only, 3 dual users (1.7 %) stopped tobacco use, but continued to use e-cigarettes. Taken together, at the end of the study, 10 (5.6 %) of the remaining 178 adolescents consumed only e-cigarettes, while 168 (94.4 %) smoked tobacco or were dual-users.

More than two thirds of all young e-cigarette users and more than three quarters of dual users also used nicotine products 18 months later. The remaining consumers showed a less frequent stay or switch to single use, instead a more frequent use of tobacco or dual use.