A prospective study of over 1,800 young Finnish twins revealed early-onset depressive disorders at age 14 significantly predicted substance abuse three years later.
Researchers found that daily smoking, smokeless tobacco use, frequent illicit drug use, frequent alcohol use and recurrent intoxication occurred even among those adolescents who were not users at baseline.
Examining twins, the study found that at age 17, one twin might have early-onset of depression and also tended to have problems with smokeless tobacco use and frequent drinking.
“The findings of this large population-based study emphasize the importance of early-onset depressive disorders in developmental trajectories of substance use”, says researcher Elina Hakola, University of Helsinki, Finland.
Analyses that control for shared genetic and familial background factors suggest that influences other than family environments, for example, the influence of peers or dispositional personality traits on health-adversing behaviors in adolescence may also be of importance in this association.
The results have important implications for educational purposes in treatment and prevention programs in adolescent health care.
Source: University of Helsinki