Introduction and aims: Understanding the risk factors that predict amphetamine use and development of amphetamine abuse or dependence (disorder) may help guide preventive interventions. This study aimed to investigate the correlates and predictors of young adults' amphetamine use and use disorders.
Design and methods: Prospective cohort, population-based study which started in Brisbane, South East Queensland (Australia) in 1981. The study participants were a cohort of 2042 young adults, followed up from birth to young adulthood. At the 21-year follow-up, amphetamine use was assessed via a self-report questionnaire, and amphetamine use disorder (AUD) was assessed using the Composite International Diagnostic Interview (CIDI-Auto). Potential predictors (15 risk factors) were assessed between baseline (antenatal visit) and the 21-year follow-up. These included participant's gender, mother's age and education, maternal marital status and quality of marital relationship, maternal tobacco and alcohol consumption, mother-child communication, child mental health and problem behaviours, child smoking and alcohol consumption and child school performance.
Results: Young adult amphetamine users were more likely to have concurrent symptoms of mental illness and problem behaviours and to use or abuse cigarettes, cannabis, or other illicit drugs. In multivariate analyses, young adults' amphetamine use and disorder were disproportionately more common among males and those who have prospectively reported aggression/delinquency or smoking at 14 years, or who have experienced childhood sexual abuse.
Conclusions: Our findings suggest that problem behaviours, smoking and childhood sexual abuse are predictors of initiation to use of amphetamines and development of amphetamine abuse and dependence.