Substance Use Consequences of Adolescent Mental Health Problems: Integrating National and High-Risk Samples.

Abstract

The risk for substance use posed by conduct problems (CP) and depressive symptoms (DS) during adolescence has been documented in the developmental psychopathology and epidemiological literatures. However, several crucial questions remain regarding the associations of CP, DS, and alcohol, marijuana, and cigarette use during adolescence. First, research to date has yielded inconsistent evidence regarding the association of DS and substance use, with evidence for positive, negative, and null associations. Second, despite the fact that CP and DS commonly co-occur, the role of their interaction in substance use has not been well characterized. Third, additional research is needed to specify how the associations between CP, DS, and substance use vary by specific substance and between and within demographic subgroups. This dissertation used data from national and high-risk adolescent samples to address these critical questions. Results indicated that, cross-sectionally and longitudinally, CP was a strong predictor of substance use, DS was a weak but positive predictor, and the interaction of CP and DS was a strong predictor, particularly among younger adolescents, such that adolescents with high levels of both CP and DS used substances most frequently. A within-group analysis of African American adolescents revealed that parental support inversely related to adolescent CP, DS, and alcohol and marijuana use, and that the parent support-substance use association was mediated by CP. Overall, the results of this work demonstrate that, although CP is often thought to be a primary predictor of substance use, DS can potentiate the relation of CP to substance use. The generalizability of these results is enhanced by the use of both national and high-risk samples and their consistency across multiple samples. The results indicate that substance use prevention efforts should target both CP and DS in early adolescence. In addition, increasing parental support may help to reduce both mental health problems and substance use during adolescence. Strategic investment in prevention of substance use can yield drastic reductions in morbidity and mortality and improvements in health. This work suggests that consideration of the contributions of mental health to adolescent substance use should be integrated into such efforts.