Mental health in adolescence as determinant of alcohol consumption trajectories in the Northern Swedish Cohort

The study aimed to analyze whether poor mental health in adolescence predicts heavy alcohol consumption over the long term. Alcohol consumption in the population cohort (n = 1010) was surveyed at the ages of 16, 18, 21, 30 and 42. Utilizing latent class growth analysis, six consumption trajectories ranging from 'Late Onset Low' to 'Early Onset High' were defined and analyzed with respect to internalization (depressiveness and anxiousness) and externalization (truancy and vandalism) at age 16. Poor mental health predicted the Early Onset High trajectory (risk ratios in relation to the compliant trajectory 3.59 for anxiousness, 2.85 for depressiveness, 5.69 for truancy and 7.75 for externalized vandalism). Moreover, significant associations were found for the Early Onset Moderate and Early Onset Low trajectories. This is the first study to show an association between internalized mental health problems in adolescence and lifelong heavy drinking. The study also confirmed a strong association between externalized behavior and heavy drinking, indicating a need of preventive measures in this group. Nevertheless, the analyses demonstrated that most teenagers with mental health problems continue along a reasonable drinking trajectory.