Professor Bruce Tonge, Ms Amanda Dudley, Dr Michael Gordon and Ms Sarah Ford
Centre for Developmental Psychiatry & Psychology, Monash University
Beyond Blue Victorian Centre of Excellence
Project completion year
Research evidence suggests a short-term effectiveness of treatments such as Cognitive Behaviour Therapy (CBT), supportive psychotherapy, antidepressant drug therapy and a combination of CBT and antidepressant drug therapy for the treatment of depression in adolescents. However, there is little data on the relative long-term efficacy of these treatments. This study examined the long-term outcomes of young people who had experienced depression as adolescents, the effectiveness of the treatment they received as adolescents, their mental health status and adjustment, biological and social predictors of treatment outcomes, and any association between the adolescents’ depression and their relationships with their parents.
The study followed young people and their parents or carers who had been involved in clinical treatment programs in Victoria’s Southern Metropolitan and Geelong regions. Young people were assessed at four times: before treatment (T1), after treatment (T2), at a six-month follow-up (T3) and between three and eight years after the third assessment (T4). The project commenced with 141 young people (aged between 18 and 26 years old) and their carers. Of these 141 participants, 130 were located during the follow-up term and 112 agreed to continue participating in the project.
Of these 112 participants, 73 were female. Mean age at T4 was 20.85 years, and mean follow-up time was 5.27 years; 104 had received treatment and eight had dropped out before treatment.
Of the 112 participants, 31 per cent were depressed at T4, with no significant difference between genders. Major depressive disorder was the most common depressive diagnosis.
Over half had experienced at least one episode of depression between T3 and T4, with 57 per cent experiencing recurrent depression. An additional 5 per cent had never recovered from the first episode and depression was ongoing. Overall, almost two-thirds had experienced further problems with depression.
Of the 108 adolescents in the analysis, 25 per cent recovered by six months, 50 per cent recovered in nine months and 75 per cent recovered within 15 months. The predicted time to recovery was reflected in scores in tests relating to: depression at T2 and T3, anxiety at T2 and T3, self-efficacy at T2, functioning at T2 and T3.
About 30 per cent of young people recovered; markers for this resilience were those who had high self-efficacy and lived in functional families.
There was no significant predictor of time to recurrence.
The findings did suggest family and parent-child relationships affect long-term mental health outcomes for formerly depressed young people. In particular, relationships between mothers and adolescents and other family influences such as low care and over-control play an important role in young people’s mental health into early adulthood.
Implications for policy, practice and further research
The results highlight the importance of clinician assessment of prognosis.
Analyses of treatment show that intervention is helpful in the short term, but that there is no evidence that counselling is better or worse than medication in the long term. The depression experienced in large numbers of the young adults at T4 demonstrates a need for more effective treatments in the long term. Approaches to treatment should focus on family relationships, particularly that between the mother and the adolescent experiencing depression.
Another group of 53 young people has been treated from 2002 to 2006, and funding is being sought to conduct follow-up studies.