A General Factor of Psychopathology Predicts Treatment and Long-Term Outcomes in Children and Adolescents With Obsessive-Compulsive Disorder

Objective: Children and adolescents with obsessive-compulsive disorder (OCD) are at risk for long-term adversity, but factors influencing long-term outcomes are unclear. A general factor of psychopathology, often referred to as the p factor, captures variance shared by all mental disorders and has predicted long-term outcomes in youth with anxiety and depressive disorders. The p factor has never been examined in relation to outcomes in pediatric OCD. Here, we examine whether the p factor predicts 4 important outcomes over both short and long durations in youth with OCD. Method: We used data from the Nordic Long-term OCD Treatment Study (NordLOTS), in which youth with OCD (N = 248, mean age = 12.83 years [SD = 2.72], 51.6% girls) received exposure-based cognitive–behavioral therapy. The p factor was estimated using parent-reported Child Behavior Checklist data at baseline and was examined in relation to clinician-rated OCD severity, clinician-rated psychosocial functioning, self-reported depressive symptoms, and self- and parent-reported quality of life directly after treatment and 1, 2, and 3 years after treatment. Results: The p factor was associated with acute treatment outcomes for OCD severity and psychosocial functioning, but not for depressive symptoms and quality of life. For the long-term outcomes, the p factor was significantly associated with all outcomes except OCD severity. The p factor outperformed traditional psychiatric comorbidity as a predictor of long-term outcomes. Conclusion: Youth with OCD who experience symptoms across multiple psychiatric domains have poorer long-term outcomes. Compared to traditional classification of psychiatric diagnoses, assessing psychopathology using a dimensional p factor approach may be advantageous for informing prognosis in pediatric OCD.