Trajectories of oppositional defiant disorder severity from adolescence to young adulthood and substance use, mental health, and behavioral problems.

Background: Oppositional Defiant Disorder (ODD) is a disruptive behavioral disorder; however, increasing evidence emphasizes irritable mood as a primary symptom of ODD.

Objectives: This study investigated whether heterogeneous groups (classes) of individuals can be differentiated based on ODD sub-dimensions (irritability and defiance) or on overall ODD symptoms longitudinally. We also examine associations between ODD trajectory class and comorbid substance use (heavy episodic drinking, cannabis use), mental health (depression and anxiety) and behavioral symptoms (ADHD, aggression and substance use) in both adolescence and young adulthood (controlling for adolescent levels of each of these concerns).

Method: Data were from a randomly recruited community sample of 662 Canadian youth (T1 ages 12-18) followed biennially for 10 years (T6 ages 22-29).

Results: Growth mixture models revealed trajectories classes of ODD based on severity of symptoms. A three-class solution provided the best fit with Low (n = 119; 18%), Moderate (n = 473; 71.5%), and High (n = 70; 10.6%) ODD classes. Class trajectory differences were similarity based on symptoms severity (rather than type) for symptom sub-dimensions (irritability defiance). Adolescent and young adult substance use, mental health symptoms, and behavioral problems were significantly higher for the High ODD trajectory class compared to both other classes. Youth in the Moderate ODD trajectory class also showed higher comorbid symptoms in adolescence and young adulthood, compared to the Low ODD trajectory class.

Conclusion: Early identification of children and adolescents with high or moderate ODD symptoms and interventions that simultaneously address defiance and irritability are supported by the findings.