The long-term mental health outcome of adolescent with depression and alcohol abuse comorbidity

Abstract Background Alcohol abuse often co-occurs with adolescent depression and about 1-2% suffer from the dual diagnosis in adolescence. This group is often undertreated or receive inadequate treatment for either of the conditions. Both conditions affect the developing brain and poor long-term outcome might be a potential risk. Yet, long-term follow-up studies are scarce. The aim of this study was to analyse if adolescent depression and alcohol abuse predict poorer mental health in adulthood compared to individuals without either or both conditions. Methods A community-based sample of individuals with adolescent depression in 1991-93 and matched non-depressed peers were followed up using a structured diagnostic interview after 15 years. The participation rate was 65% (depressed n = 227; non-depressed controls n = 155). Information on alcohol abuse in adolescence was collected at baseline with a structured interview. The outcome was mental disorders between the ages 19-31 years; information on depression and alcohol abuse was collected at the follow-up with a structured diagnostic interview. The statistical method used was binary logistic regression. Results Adolescents with depression and alcohol abuse had an excess risk of recurrence of depression (OR 2.12, p < 0.05) and alcohol abuse (OR 6.72, p < 0.01) in adulthood, compared with adolescents with depression only, even when adjusted for confounders. Adolescents with alcohol abuse only had not significantly worse long-term outcome compared with their healthy peers. Conclusions The co-occurrence of depression and alcohol abuse in adolescence is associated with long-lasting health consequences compared to either condition alone. This finding indicates that there is a need to prioritize this group of patients that is at risk of suboptimal treatment, and to further develop effective treatment adjusted to the co-occurring condition. Key messages The co-occurrence of adolescent depression and alcohol abuse has long lasting mental health consequences compared to either condition alone. Improved treatment methods are important for this group of adolescents.