Integrated vs. parallel treatment in adolescents with substance use and comorbid disorders: A randomized trial

Integrated treatments are often recommended for adolescents with substance use disorders (SUD) and comorbid pathologies. This study aims to compare the effectiveness of two different intervention programs (integrated and parallel) and to investigate treatment outcome predictors. Seventy-five adolescents (13-17 years old) with substance use and comorbid disorders referred to our outpatient program were randomized to integrated (n = 33) or parallel (n = 32) treatment groups. Their sociodemographic variables, psychopathology, substance use problems, and global functioning were assessed at baseline and 12 months after treatment initiation. Both treatments were associated with positive pre-post changes in several outcome variables (severity of school, family, and psychiatric problems; global functioning; and stage of change). Integrated treatment showed better outcome on adherence (χ2 = 14.328; p > .001) and a composite global measure based on the severity of drug-related problems (χ2 = 8.833, p = .003). Following an adaptive treatment strategy, we offered patients who dropped out of parallel treatment (n = 12) the possibility of entering integrated treatment. Eleven of them accepted and constituted a third comparison group (parallel-to-integrated). Multivariate logistic regression analysis showed that the likelihood of a positive global treatment outcome increased with integrated or parallel-to-integrated treatment, internalizing or mixed comorbid disorders, older age, and fewer legal issues. Integrated treatment showed better adherence and global treatment outcomes than parallel treatment in adolescent patients with dual disorders. Older age and fewer legal issues were also related to a positive global treatment outcome.