Trajectories of alcohol use and high school dropout: A 7-year longitudinal study

Background: Alcohol use is common among many but not all adolescents. The frequency and age of initiation also varies. The purpose of this study is to describe developmental trajectories of alcohol use among adolescents from Grade 6-12, and to examine the association between alcohol use trajectories and high school dropout. Methods: The sample consisted of a cohort of 624 randomly-selected students (52% males; 48% White, 36% Black, 12% Latino) who participated in the Healthy Teens Longitudinal Study. Students reported frequency of drinking beer, wine, or liquor within the past 30 days. Schools provided high school completion data. We used semi-parametric group based modeling to identify the trajectories and nonparametric tests to examine the association of alcohol trajectories and dropout. Results: Overall, cross-sectional prevalence of drinking alcohol doubled from Grade 6 (19%) to Grade 12 (40%). Longitudinally, adolescents in this sample followed four distinct alcohol use trajectories: None/Low (58% of total sample), Stable-Low (23%), Late Starters-High (13%), and Early Starters-High (6%). Rates of school dropout significantly increased with alcohol consumption (X2 =11.04, p =.01): None/Low (dropout=14%), Stable-Low (21%), Late Starters-High (24%), and Early Starters-High (29%). The demographic composition of trajectories did not differ by race or sex. Conclusion: This longitudinal study highlights the diversity of alcohol use among adolescents as they move from middle to high school. Dropout rates were high among adolescents who reported more alcohol use, particularly those initiating the behavior early. More research is needed to examine whether alcohol is an indicator of other problem behaviors.