Co-use of smokeless nicotine products and marijuana among youth in Denmark: a cross-sectional population-based study

Previous research suggests a gateway effect between the use of nicotine products and other harmful drugs, such as marijuana. As the use of smokeless nicotine products among youth in Denmark has been increasing, we aimed to identify factors associated with marijuana use and examined the co-use of smokeless nicotine products and marijuana among Danish youth.

We used data from a cross-sectional Danish nationwide questionnaire-based survey among 15- to 29-year-olds conducted in 2022. Overall, 6236 were included in the analyses. Multiple logistic regression analyses were carried out to assess associations between use of smokeless nicotine products and marijuana ever-use and frequent use (⩾10 times). A multiple multinomial logistic regression analysis tested whether the association varied across the frequency of marijuana use.

A total of 41.9% had ever used marijuana, of which 38.6% reported frequent use. Factors associated with marijuana use were current use of other nicotine products, being male, having medium- or long-cycle higher education without a current occupation, excessive binge drinking, and living in the Capital Region. Youth who used smokeless nicotine products had markedly higher odds of ever using marijuana (aOR: 4.13, 95%CI[3.3, 5.05]). Among respondents who had ever used marijuana, use of smokeless nicotine products was associated with frequent marijuana use (aOR: 1.73, 95%CI[1.39, 2.15]).

This study found a significant co-use of smokeless nicotine products and marijuana in terms of both marijuana ever-use and frequent marijuana use. This highlights the potential additive consequences of the increasing use of smokeless nicotine products, which calls for preventive actions targeting youth.