title: Neural Correlates of Response to Pharmacotherapy in Obsessive-Compulsive Disorder: Individualized Cortical Morphology-Based Structural Covariance.
abstract: BACKGROUND
  Primary pharmacotherapy regimen for obsessive-compulsive disorder (OCD) named Serotonin reuptake inhibitors (SRIs) does not attain sufficient symptom improvement in 40-60% of OCD. We aimed to decode the differential profile of OCD-related brain pathology per subject in the context of cortical surface area (CSA) or thickness (CT)-based individualized structural covariance (ISC) and to demonstrate the potential of which as a biomarker of treatment response to SRI-based pharmacotherapy in OCD using the support vector machine (SVM).
  
  
  METHODS
  T1-weighted magnetic resonance imaging was obtained at 3T from 56 unmedicated OCD subjects and 75 healthy controls (HCs) at baseline. After 4months of SRI-based pharmacotherapy, the OCD subjects were classified as responders (OCD-R,N=25; ≥35% improvement) or nonresponders (OCD-NR,N=31; <35% improvement) according to the percentage change in the Yale-Brown Obsessive Compulsive Scale total score. Cortical ISCs sustaining between-group difference (p<.001) for every run of leave-one-out group-comparison were packaged as feature set for group classification using the SVM.
  
  
  RESULTS
  An optimal feature set of the top 12 ISCs including a CT-ISC between the dorsolateral prefrontal cortex versus precuneus, a CSA-ISC between the anterior insula versus intraparietal sulcus, as well as perisylvian area-related ISCs predicted the initial prognosis of OCD as OCD-R or OCD-NR with an accuracy of 89.0% (sensitivity 88.4%, specificity 90.1%). Extended sets of ISCs distinguished the OCD subjects from the HCs with 90.7-95.6% accuracy (sensitivity 90.8-96.2%, specificity 91.1-95.0%).
  
  
  CONCLUSIONS
  We showed the potential of cortical morphology-based ISCs, which reflect dysfunctional cortical maturation process, as a possible biomarker that predicts the clinical treatment response to SRI-based pharmacotherapy in OCD.
authors.affiliation: Department of Psychiatry & Behavioral Science, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Je-Yeon
authors.initials: JY
authors.lastname: Yun
authors.affiliation: Department of Psychiatry & Behavioral Science, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Joon Hwan
authors.initials: JH
authors.lastname: Jang
authors.affiliation: Department of Psychiatry & Behavioral Science, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sung Nyun
authors.initials: SN
authors.lastname: Kim
authors.affiliation: Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea.
authors.forename: Wi Hoon
authors.initials: WH
authors.lastname: Jung
authors.affiliation: Department of Psychiatry & Behavioral Science, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Human Behavioral Medicine, SNU-MRC, Seoul, Republic of Korea; Department of Brain & Cognitive Sciences, College of Natural Science, Seoul National University, Seoul, Republic of Korea. Electronic address: kwonjs@snu.ac.kr.
authors.forename: Jun Soo
authors.initials: JS
authors.lastname: Kwon
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000187:drug effects / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D009771:Obsessive-Compulsive Disorder / Q000188:drug therapy* / Q000473:pathology*; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D060388:Support Vector Machine; D055815:Young Adult
chemical_list: D017367:Selective Serotonin Reuptake Inhibitors
keywords: obsessive-compulsive disorder; pharmacotherapy; structural covariance network; support vector machine; treatment response