Background: Several risk factors for alcohol and other substance use disorders (SUDs) have been identified, but it is not well understood whether their associations with SUD are independent of each other. In particular, it is not well known, whether the associations between behavioral and affective factors and SUDs are independent of other risk factors. The incidence of SUDs peaks by young adulthood making epidemiological studies of SUDs in young adults informative.
Methods: In a comprehensive population-based survey of mental health in Finnish young adults (aged 21-35 years, n = 605), structured clinical interview (SCID-I) complemented by medical record data from all lifetime hospital and outpatient treatments were used to diagnose SUDs. We estimated the prevalences of lifetime DSM-IV SUDs, and investigated their associations with correlates from four domains representing: (1) behavioral and affective factors, (2) parental factors, (3) early initiation of substance use, and (4) educational factors. Independence of the association of behavioral and affective factors with SUD was investigated.
Results: Lifetime prevalences of abuse or dependence of any substance, alcohol, and any illicit substance were 14.2%, 13.1%, and 4.4%, respectively. Correlates from all four domains were associated with SUD. The associations between behavioral and affective factors (attention or behavior problems at school, aggression, anxiousness) and SUD were largely independent of other correlates, whereas only daily smoking and low education associated with SUD after adjustment for behavioral and affective factors.
Conclusion: Alcohol use disorders are common in Finnish young adults, whereas other SUDs are less common than in many other developed countries. Our cross-sectional analyses suggested that the association between behavioral and affective factors and SUD was only partly accounted for by other correlates, such as early initiation of substance use and parental alcohol problems. In contrast, associations between many other factors and SUD were non-significant when adjusted for behavioral and affective factors.