E-cigarette and cannabis use and susceptibility among secondary school students in Thailand

This study aims to examine the association between vaping status and cannabis use and susceptibility among a representative sample of secondary school students in Thailand.

A cross-sectional, school-based study.

We surveyed secondary-school students across Thailand (June-September 2024). Outcomes were (1) susceptibility to cannabis use, measured using a validated intention/willingness scale, and (2) current cannabis use (past 30 days). The main exposure was vaping status (non-susceptible non-user, susceptible non-user, ever user, current user). Covariates included sex, cigarette smoking, alcohol use, and perceived close-friend vaping. Multivariable logistic regression estimated adjusted odds ratios (AOR).

Among students with complete data (n = 3583 for susceptibility; n = 3784 for current use), vaping status showed strong graded associations with both outcomes. Compared with non-susceptible non-users, odds of cannabis susceptibility were higher among susceptible non-users (AOR = 10.44), current vapers (AOR = 5.50), and ever vapers (AOR = 3.73). For current cannabis use, odds were elevated among current (AOR = 7.13) and ever vapers (AOR = 6.13), while susceptible non-users did not differ from the reference. Clustering with other substances was pronounced: current and ever smokers and current and ever drinkers had substantially higher odds of cannabis use. Male sex and close-friend vaping were also associated.

Vaping was independently associated with higher cannabis susceptibility and use among Thai secondary-school students. Despite the limits of cross-sectional data, patterns align with stage-based/common-liability models and support integrated school-based prevention that addresses multi-product use and shared psychosocial and peer-norm risks amid Thailand's shifting policy context.