Poster #13 - Brain Structure Predicting Response to Therapy in Children and Adolescents with Obsessive-Compulsive Disorder

• In Event: 2-055 - Poster Session 06
  In Poster Session: PS 06 Section - Biological Processes: Neuroscience and Genetics

Integrative Statement

Obsessive-compulsive disorder (OCD) is characterized by the presence of obsessions (i.e. intrusive thoughts, images, or impulses) and compulsions (i.e. repetitive actions performed to prevent or mitigate distress). Cognitive Behavioral Therapy (CBT) with exposure and ritual prevention is an effective, first-line treatment for pediatric OCD. While functional neural predictors of treatment outcomes have been identified in adults with OCD, studies have yet to characterize clear neural predictors in children. Herein, we sought to identify brain structural markers of CBT response in children and adolescents with OCD. Such signatures would be stable and easy to measure and could help guide and personalize treatment plans. Twenty-eight unmedicated children and adolescents with OCD and 27 age- and sex-matched healthy participants (5-18 years old) completed high-resolution MRI scans (0.8mm isotropic voxels). Patients with OCD completed weekly CBT over the following 16 weeks. FreeSurfer v6 was used for structural processing, including extraction of cortical thickness from 148 cortical areas from the Destrieux et a., 2010 atlas. Linear mixed-effects models were used to identify brain regions where cortical thickness moderated the slope of change in OCD severity (Yale-Brown Obsessive-Compulsive Scale [YBOCS] scores) across pre-, mid-, and post-treatment assessments, allowing for missing data and controlling for age, sex, and IQ. False discovery rate was used for multiple comparisons correction. A confirmatory vertex-wise analysis was run in QDEC predicting change in YBOCS scores using stringent multiple comparisons correction. Thinner cortex in nine regions significantly predicted improvement in YBOCS scores (all t>3.4, FDR-corrected p<.05). These regions included the middle and superior frontal, angular, lingual, precentral, superior temporal, and supramarginal gyri (SMG). Vertex-wise analysis confirmed a significant cluster in the left SMG. As expected in this age range, these regions tended to show negative associations between thickness and age or pubertal development. Further analyses examining structural connectivity using diffusion-weighted imaging are underway. The current study used high-resolution MRI to identify structural neural predictors of CBT response in unmedicated children/adolescents with OCD. While most patients showed symptom improvements, responses varied across the sample. Thinner cortex in fronto-parietal regions predicted greater treatment improvements. These findings suggest that maturation of fronto-parietal circuits might facilitate CBT response in pediatric OCD and that these circuits may be targets for novel treatments and early prevention strategies.

Authors

• David Pagliaccio, New York State Psychiatric Institute
  Presenting Author

• Moira Rynn, Duke University
  Non-Presenting Author

• Rachel Marsh, New York State Psychiatric Institute
  Non-Presenting Author