Aims: To evaluate the association between impulsivity, age of first alcohol consumption (AFD) and substance use disorders (SUD) in a non-clinical sample of adolescents.
Design and setting: Population-based case-control study of male adolescents between 15 and 20 years of age nested in a community survey in southern Brazil.
Participants: Cases were drug or alcohol abusers/dependents defined according to DSM-IV abuse/dependence criteria (n = 63). Individuals who had experienced alcohol use but where non-abusers served as controls (n = 355). Cases and controls completed a structured face-to-face interview.
Measurements: The Mini International Neuropsychiatric Interview (MINI) was completed during the original survey and used to identify cases and controls. Impulsivity was measured by means of the Barratt Impulsivity Scale (BIS 11). Self-reported AFD and socio-demographic data were collected and analyzed through logistic regression according to a hierarchical model.
Findings: Impulsivity and AFD were significantly associated with SUD. Both higher impulsivity [odds ratio (OR) 3.3, 95% confidence interval (CI) 1.4-7.8] and earlier AFD (OR 1.2, 95% CI 1.0-1.3) remained associated with SUD after model adjustments.
Conclusions: The findings from this population-based case-control study suggest that impulsivity and age of first alcoholic drink are associated strongly with alcohol and drug problems. Additionally, impulsivity seems to contribute to a premature exposure to alcohol by hastening the AFD. If the temporal effect of these associations is confirmed in longitudinal designs including broader population groups, our findings may contribute to the development of clinical and policy interventions aiming at reducing the incidence and morbidity associated with substance-related problems among adolescents.