Nicotine dependence in adolescence predicts later drug criminality: a register-based follow-up of adolescent psychiatric inpatients.

Cigarette smoking is common among adolescent psychiatric patients and often precedes the initiation of substance and illicit drug use. This study investigates the association of nicotine dependence (ND), assessed already in adolescence, to subsequent drug crime offenses committed up to young adulthood. The special focus was to examine the dose-response between adolescent ND and later drug-crime offenses. The initial data consist of former adolescent psychiatric inpatients treated in psychiatric inpatient care between the ages 13-17 years. Adolescent DSM-IV based psychiatric disorders were based on the semi-structural diagnostic K-SADS-PL interview. ND in adolescence was measured using the modified Fagerström Tolerance Questionnaire for children and adolescents. Follow-up data on crimes of the study subjects from 15 years of age to early adulthood was obtained from the nationwide Legal Register Center of Finland. A total of 60 (11.8%) drug crime offenders were identified from the initial study population. The likelihood for drug crime offending was statistically significantly increased among those with moderate to severe ND already in adolescence. The higher level of adolescent ND indicated greater number of drug offenses. The common characteristics of drug crime offenders were male gender, out-of-home placement background, exposure to parental divorce and a diagnosis for affective, conduct and substance-use disorder in adolescence. Our study finding, that higher level of ND in adolescence predicts greater number of drug crime offenses up to young adulthood, warrants identification of adolescent smokers at-risk of later drug-related crimes.