Age of tobacco, nicotine and cannabis use initiation in Switzerland: a sequence analysis among adolescents and young adults.

Background: To explore at what age youth start using tobacco and/or nicotine products, which product is used first, product initiation sequences, and whether some socio-demographic characteristics are associated with substance use initiation.

Methods: Data were collected from an online questionnaire disseminated through social media and professional partners, targeting youth aged 14-25 in French-speaking Switzerland in August 2022. The final sample included 1362 participants. Respondents were asked whether they had already used cigarettes, e-cigarettes, hookah, snus, or cannabis at least once in their life (yes/no) and the age of the first time was asked for each substance when the answer was positive. Additionally, participants were asked about their substance use in the past 30 days. Respondents were classified according to age at onset of each tobacco/nicotine and cannabis product, and comparisons were made based on sociodemographic variables, including gender (cisgender female/cisgender male/transgender), perceived socioeconomic status (below average/average/above average), and age.

Results: Overall, in addition to those who reported no consumption, four distinct initiation profiles emerged from the classification. Cigarettes remain the most commonly used first product with an average age of 15.7 years. While cigarettes and hookah are present in all profiles, the order of first consumption varies from one profile to another, with cigarettes coming first in two profiles, hookah in one and e-cigarettes in the last. Furthermore, while the most common profile contains experimental consumption of the five products considered, some profiles do not contain cannabis, e-cigarettes and/or snus, for example. When divided by age groups, both 14-17-year-olds and 18-21-year-olds reported cigarette as their first product of initiation. Across the separate age groups (14-17, 18-21, 22-25), cigarettes consistently emerge as the primary used on average.

Conclusions: Cigarettes remain the first product to be used, but the younger the respondents, the earlier they start using e-cigarettes, and very close to cigarettes. Regarding current consumption patterns, e-cigarettes are becoming increasingly prominent.