In summary, the rate of transition from use to dependence is higher for nicotine user than for alcohol, cannabis or cocaine users. Individuals from some ethnic minority groups and those with a history of psychiatric and substance dependence comorbidity showed an increased risk of transitioning from use to dependence. Several predictors of dependence were common across the substances assessed, suggesting the existence of shared mechanisms. Promoting outreach and treatment of individuals from minority population groups or those with a primary mental disorder may constitute an important strategy to prevent transition to substance dependence.
