Background: Tobacco use among adolescents is a significant public health concern, with early initiation leading to long-term health risks. Understanding the factors that contribute to the initiation of tobacco use is crucial for developing effective prevention strategies. This study investigates the roles of substance use harm knowledge and tobacco susceptibility in mediating the relationship between social gradients (race, ethnicity, and socioeconomic status) and tobacco use initiation among adolescents. Methods: Data from the Adolescent Brain Cognitive Development (ABCD) study, comprising a racially, ethnically, and economically diverse sample of tobacco-naive adolescents aged 9 to 16, were analyzed. Structural equation modeling (SEM) was used to test whether substance use harm knowledge and tobacco susceptibility mediate the effects of socioeconomic status (SES) on the initiation of tobacco use. Results: Findings indicated that both substance use harm knowledge and tobacco susceptibility partially mediate the relationship between SES and tobacco use initiation. Adolescents from lower SES backgrounds exhibited lower levels of harm knowledge and higher levels of tobacco susceptibility, which increased their likelihood of initiating tobacco use. Conclusion: This study highlights the complex interplay between social determinants and individual cognitive and psychological factors in influencing tobacco use initiation among adolescents. Public health interventions that enhance harm knowledge and reduce susceptibility to tobacco use are crucial for preventing initiation, particularly among racially, ethnically, and economically diverse adolescents. These efforts can help reduce health disparities and promote health equity.

Background: Minorities’ Diminished Returns (MDRs) theory posits that socioeconomic resources have weaker protective effects on health and behavior for racial and ethnic minorities compared to Whites. This study examines whether tobacco susceptibility, defined as curiosity, intention, and openness to future tobacco use, mediates the diminished returns of family income on tobacco initiation among Black adolescents. Methods: Data from the Adolescent Brain Cognitive Development (ABCD) Study were analyzed. Participants were followed from age 9 to 16. All participants were tobacco naïve at baseline. Tobacco susceptibility was assessed through self-reported measures of curiosity, intention, and openness to future tobacco use. Structural equation modeling (SEM) was used to examine the relationship between family income, tobacco susceptibility, and tobacco initiation. Results: Overall, 10,653 Black or White youth entered our analysis. The analysis revealed that higher family income was less effective in preventing tobacco initiation among Black adolescents. Tobacco susceptibility significantly predicted tobacco initiation and partially mediated the relationship between family income and tobacco initiation. Conclusions: Tobacco susceptibility explains some of the diminished returns of family income on tobacco initiation among Black adolescents. Interventions aimed at reducing tobacco susceptibility may enhance the protective effects of family income and help mitigate health disparities.

Background: Recent research has identified structural racism—systemic policies and practices that perpetuate racial inequalities—as a significant social determinant of population health. Studies utilizing data from the Adolescent Brain Cognitive Development (ABCD) study have shown an association between higher levels of state-level structural racism and increased tobacco use among youth in the United States. However, there has been limited exploration of the psychosocial mediators of this relationship, particularly in the context of youth aged 10-16 years. Objective: This study aimed to assess the roles of socioeconomic status (SES), tobacco susceptibility, and perceived discrimination as potential mediators in the relationship between state-level structural racism and youth tobacco initiation rates. Methods: We analyzed data from the ABCD study, a nationally representative longitudinal survey of 11,698 youth followed from ages 9/10 to 15/16. These data were combined with state-level indicators of structural racism. We employed structural equation modeling (SEM) to investigate the mediators of the association between structural racism and self-reported initiation of tobacco use, while controlling for individual and state-level covariates. Results: Our findings indicate that higher levels of structural racism were associated with increased rates of tobacco initiation among youth. This relationship was partially mediated by lower SES, but not by perceived discrimination or tobacco susceptibility. Conclusion: The association between structural racism and youth tobacco initiation appears to be influenced in part by the lower SES prevalent in states with higher levels of racism. These results highlight the need for addressing both racism and SES inequalities as key strategies for reducing tobacco disparities among youth.