From individual motivation to substance use initiation: A longitudinal cohort study assessing the associations between reward sensitivity and subsequent risk of substance use initiation among US adolescents

Background: Substance use in youth remains a pressing problem in the United States. Existing studies have shown the importance of neuropathways responsible for affective response and reward motivation in adolescents’ substance use initiation and maintenance. However, limited observational studies have explored the relationship between aspects of behavioral motivation traits and the likelihood of substance use initiation in adolescents. In this prospective cohort study, we assessed the associations between behavioral motivation traits based on the Behavioral Inhibition and Approach Systems (BIS-BAS) Scale and substance use initiation using data from the Adolescent Brain Cognitive Development (ABCD) study. Method: In the 9216 eligible sample population, we assessed the associations between mean Behavioral Inhibition System (BIS) / Behavioral Approach System (BAS) scores measured at year 2 of the ABCD study and substance use initiation at year 3 of the ABCD study using multivariable logistic regressions adjusting for ABCD study site, sampling weights, as well as sociodemographic characteristics. Results: We found that higher BIS mean score was associated with higher odds of initiating substance use at year 3 (AOR=1.20, 95 % CI: 1.03, 1.40). Out of three BAS measure categories, only BAS Fun-seeking mean score was positively associated with higher odds of initiating substance use at year 3 (AOR=1.23, 95 % CI: 1.07, 1.43). Conclusion: Our study showed that inhibitory and fun-seeking behavioral tendencies are associated with an increased likelihood of substance use initiation in adolescents. Our findings suggest a potential pathway linking emotional traits to early substance initiation in adolescents.