Predictors of growth trajectories of substance use from 9th to 11th grade among Hispanic adolescents in Southern California

Previous studies have documented cultural risk and protective factors for substance use among Hispanic adolescents, but few studies have investigated these associations longitudinally. Some risk and protective factors may exert their influences earlier in childhood, whereas the effects of other factors may emerge later in adolescence. This study examined the predictors of growth trajectories of substance use from 9th to 11th grade among 1668 Hispanic adolescents in Southern California, using individual growth curve analyses. From 9th to 11th grade, use of cigarettes, alcohol, and marijuana increased significantly in the overall sample, although there was considerable heterogeneity in trajectories. Significant risk factors for substance use in 9th grade included perceived discrimination, fatalism, and low levels of respeto. Significant predictors of growth in substance use between 9th and 11th grade included male gender, Hispanic acculturation, perceived discrimination, respeto, fatalism, and friends' and parents' use. Results indicate that the effects of perceived discrimination, friends' use, and parents' use occur prior to 9th grade, whereas other variables are associated with escalation of substance use during high school. Substance use prevention interventions are needed throughout early and mid-adolescence. Prevention curricula may be more effective if they address the specific risk and protective factors that are most relevant at each stage of development.