Multiple Risk Factor Model Predicting Cannabis Use and Use Disorders: A Longitudinal Study

Abstract

Background: Identification of factors associated with the initiation and continuation of cannabis use is important for any preventive work. Objectives: This study aimed to examine the early life course predictors of cannabis use and the development of cannabis use disorder in early adulthood. Methods: Data from Mater Hospital and University of Queensland Study of Pregnancy (MUSP), a population-based prospective birth cohort study. Participants were a cohort of 2,493 young adults who completed the life-time version of the Composite International Diagnostic Interview-computerized version (CIDI-Auto) at the 21-year follow-up, and for whom data were available from previous follow-ups. Ever use and age at first use of cannabis was assessed via self-report, and cannabis use disorder was measured based on Diagnostic and Statistical Manual version IV (DSM-IV) diagnostic criteria. Life course predictors were obtained between the child's birth and the 14-year follow-up. Results: Of 2,493 young adults, 51.4% reported having ever used cannabis, and 21.1% of young adults were classified as having ever had a cannabis use disorder. Child's gender, changes in maternal marital status, maternal smoking, child school performance, childhood sexual abuse, early adolescence smoking and alcohol consumption, and adolescent aggression/delinquency were strongly associated with young adult cannabis use and use disorder. Exposure to multiple risk factors was associated with greater risk of outcomes. Conclusions: There are a number of strong predictors of cannabis use identified in this study. They suggest that the social context within which children are reared has a major influence on cannabis use and use disorders.

Keywords :

• Cannabis
• cannabis use disorder
• predictor
• young adult

ACKNOWLEDGMENTS

We thank all participants in the study and the MUSP data collection team. We also thank Greg Shuttlewood, the data manager, and Rosemary Aird and her colleagues for Phase 7 data collection. The core study was funded by the National Health and Medical Research Council (NHMRC) of Australia, but the views expressed in the article are those of the authors and not necessarily those of any funding body.