Associations between Marijuana Use Trajectories and Educational and Occupational Success for Canadian Youth

Introduction: Young adulthood is a particularly critical stage when the personal, social, and economic foundations for life-long health and healthy lifestyles are established. Key developmental tasks of this phase include building the capacity for financial and residential independence through post-secondary education and job training. However, youth and young adults are also among the heaviest cannabis users, which may create challenges for navigating these developmental tasks successfully. As legalization of cannabis use in Canada nears, research-based knowledge about the consequences of different patterns of marijuana use for these health determinants is needed to increase our ability to anticipate potential harms for Canadian youth in the short-term, and to monitor the impact of the the legalization and regulation of marijuana use for Canadian youth over time. In the current study, we estimated variability in marijuana use trajectories using latent class growth curve analyses and asked how these trajectories relate to educational and occupational success in young adulthood? Specially, we examine trajectory differences in educational attainment and occupational prestige, financial strain, work characteristics (i.e., number of jobs, income), and perceived workplace stress.

Methods: We used from the Victoria Healthy Youth Survey, a 10-year prospective study of a random community sample of 662 youth (48% male; M_age = 15.5) followed biennially for six assessments. Models adjusted for baseline age, sex, SES, high school grades, heavy drinking and oppositional defiant disorder symptoms.

Results: Five marijuana use groups were identified: Abstainers (29%), Occasional Users (27%), Decreasers (14%), Increasers (20%), and Chronic Users (11%). Increasers and Chronic users (our highest risk classes) had the lowest levels of educational attainment and occupational prestige and worked a greater number of jobs compared to Abstainers. Increasers were also more likely to have trouble paying for necessities, delay medical attention, and have lower income compared to abstainers. Decreasers, who had high early adolescent use but quit over time, had lower educational attainment, but did not differ from Abstainers in occupational prestige or income. Groups did not differ on perceived workplace stress.

Conclusions: Compared to US samples, our work finds that a greater proportion of Canadian youth are in “high risk” groups, characterized by earlier onset and higher frequency of use. Moreover, we find that early onset and persistent high or increasingly frequent use of marijuana creates barriers for educational and occupational success in young adulthood. These potential barriers and prevention opportunities will be discussed.