Globally, harmful alcohol use continues to be a major modifiable contributor to the burden of disease. In 2004/5, alcohol accounted for 27% (=$15.3 billion) of the Australian social costs of drug abuse, with alcohol use disorder (AUD), defined as a cluster of cognitive, behavioural and physiological symptoms indicating continued alcohol use despite significant problems, representing the most costly alcohol-related harm. Initiation of alcohol use is a rite of passage for many adolescents yet an alarming number drink at levels that put them at risk of harm. Such risky drinking patterns are strongly associated with the development of AUD and can trigger a cascade of lifelong adverse outcomes, such as mental disorders, suicide, other illicit drug use and antisocial behaviour as well as early onset of heart disease, stroke and cancer.
Australian and international adult population data indicate that the peak age of onset of AUD is 18 years, thus a deeper understanding of the adolescent experience is vital if we are to identify modifiable risk factors and intervene early in the developmental course of this disabling disorder. More broadly, despite spectacular improvements in the health of young children, indicators of adolescent health, including violence and injury associated with alcohol use, remain unchanged over the past 50 years. Through initiatives such as the recently established Lancet Commission on Adolescent Health and Wellbeing adolescents are now central in efforts to improve global health.
The proposed study responds to an urgent call for high quality, long-term prospective cohort studies to better understand the health burden of adolescent drinking. Critical unanswered questions include: How soon after drinking initiation do AUD symptoms begin to emerge? Which symptoms come first? Do the symptoms unfold in a predictable pattern? In what ways do the emerging symptoms interact with individual, peer, family and environmental risk factors to predict the transition to disorder?
The aim of the project is to conduct a world-first, intensive, longitudinal study of the developmental course of AUD across adolescence and young adulthood. The overarching hypothesis is that the timing, rate and order of symptom development will account for differences in the risk of developing AUD. The specific objectives are to 1) prospectively measure the presence, age at onset and temporal unfolding of AUD symptoms and 2) determine the individual, peer, family and environmental factors that, in the presence of early symptoms, predict transition to AUD.