Objective: Depression is the most prominent mental health disorder among youth and has a profound impact with respect to morbidity and mortality if not addressed. The Treatment for Adolescent Depression Study (TADS) is one of the largest randomized controlled trials that compared the effectiveness of four treatments: cognitive-behavioral therapy (CBT); fluoxetine (FLX); combined cognitive-behavioral and fluoxetine treatment (COMB); and placebo (PBO). However, meaningful heterogeneous treatment courses are masked by these group mean comparisons of treatment impact. The present study sought to characterize the acute phase symptom trajectories of the depressed teens enrolled in TADS and to explore predictors of these trajectories, including TADS treatment condition.
Method: The TADS sample of 439 adolescent participants diagnosed with major depressive disorder was subjected to growth mixture modeling (GMM) to evaluate subgroups of adolescents with unique trajectories of depression symptom change.
Results: Growth mixture modeling revealed three unique classes of adolescents: (1) a high-severity class with early significant improvement; (2) a high-severity class with limited symptom change; and (3) a moderate severity class with late significant improvement. Baseline predictors of class membership included treatment condition, sex, age, stage of change, depression severity, number of comorbid disorders, hopelessness, melancholia, suicidality, and cognitive distortions.
Conclusion: Results of this study may have implications for the selection of which treatment to use for which depressed adolescent.
Clinical trial registration information: Treatment for Adolescents With Depression Study (TADS); https://clinicaltrials.gov/; NCT00006286.
Keywords: cognitive-behavioral therapy; depression; treatment.
Copyright © 2019 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.