Preventing the transitions in poly-tobacco use among young adults: A latent transition analysis of a smoking reduction intervention trial

Objective: The escalating trends in poly-tobacco use among young people are worrying due to the heightened health consequences associated with use. This study aims to re-analyze data from a smoking reduction intervention applying latent transition analysis (LTA) to explore the effect of a smoking reduction intervention on the transition between tobacco and nicotine use behavior patterns, particularly poly-tobacco use, over time. Additionally, the effect of sociodemographic variables on transition patterns was explored.

Methods: From 2018 to 2020, a two-armed randomized controlled trial was conducted to evaluate a smoking reduction intervention focusing on a comprehensive school tobacco policy across 14 vocational schools in Denmark. Baseline and five-month follow-up surveys assessed self-reported use of cigarettes, e-cigarettes, smokeless tobacco, and waterpipe. This study was a secondary data analysis using latent transition analysis (LTA). The primary analysis of the trial did not find a significant overall effect of the intervention on tobacco use.

Results: A total of 2,158 students completed the baseline and/or follow-up surveys (mean age: 20.8 years, 49.5 % female). At both time points, three latent classes of tobacco and nicotine use behavior emerged (non-users, cigarette users, and poly-tobacco users). Intervention school students had 36 % lower odds of transitioning from cigarette use at baseline to poly-tobacco use at follow-up (OR = 0.64; 95 % CI 0.41,0.99, p = 0.047) compared to control school students. Males and younger students had increased odds of transitioning from cigarette use to poly-tobacco. In contrast, students of non-Danish origins had increased odds of transitioning from poly-tobacco use to non-use.

Conclusions: This study demonstrates the effectiveness of a smoking reduction intervention in reducing the progression toward poly-tobacco use among vocational school students.