Developmental Trajectories of Cigarette Smoking in Sexual Minority Youth: Application of General Growth Mixture Modeling

Studies repeatedly document higher risk of tobacco use among sexual minority (i.e., gay, lesbian, bisexual) compared to heterosexual youth. However, studies examining sexual orientation group differences in the longitudinal development of tobacco smoking from adolescence through young adulthood are uncommon. At the same time, general growth mixture modeling (GGMM) has emerged as an important method for distinguishing subgroups of youth expressing different developmental trajectories of tobacco use. This analysis approach commonly identifies a subgroup of youth who initiate smoking at a relatively early age, display a steep escalation of use, and are at elevated risk for acquiring nicotine dependence. The objectives of this study are to apply GGMM to: (1) estimate smoking trajectories in a large community-based longitudinal cohort study of adolescents; (2) examine the association of sexual orientation to the smoking trajectories; and (3) describe key risk and protective factors (e.g., depressive symptoms, self-esteem, and family use of tobacco) associated with tobacco smoking trajectories among sexual minority youth. To achieve these objectives, we use repeated measures data collected from more than 13000 male and female participants of the Growing Up Today Study (GUTS). Smoking data were collected from GUTS participants when they ranged in age from 10 to 23 years over 5 follow-up assessments occurring, on average, 18 months apart. Approximately 8.5% of males and 16.0% of females identified as sexual minority (gay/lesbian, bisexual, or mostly heterosexual) over the study follow up period. Findings will inform interventions to prevent and/or reduce tobacco smoking among sexual minority youth.