title: Brain connectivity and prediction of relapse after cognitive-behavioral therapy in obsessive-compulsive disorder.
abstract: BACKGROUND
  Intensive cognitive-behavioral therapy (CBT) can effectively reduce symptoms in obsessive-compulsive disorder (OCD). However, many relapse after treatment. Few studies have investigated biological markers predictive of follow-up clinical status. The objective was to determine if brain network connectivity patterns prior to intensive CBT predict worsening of clinical symptoms during follow-up.
  
  
  METHODS
  We acquired resting-state functional magnetic resonance imaging data from 17 adults with OCD prior to and following 4 weeks of intensive CBT. Functional connectivity data were analyzed to yield graph-theory metrics. We examined the relationship between pre-treatment connectome properties and OCD clinical symptoms before and after treatment and during a 12-month follow-up period.
  
  
  RESULTS
  Mean OCD symptom decrease was 40.4 ± 16.4% pre- to post-treatment (64.7% responded; 58.8% remitted), but 35.3% experienced clinically significant worsening during follow-up. From pre- to post-treatment, small-worldness and clustering coefficient significantly increased. Decreases in modularity correlated with decreases in OCD symptoms. Higher pre-treatment small-world connectivity was significantly associated with worsening of OCD symptoms during the follow-up period. Psychometric and neurocognitive measures pre- and post-treatment were not significant predictors.
  
  
  CONCLUSIONS
  This is the first graph-theory connectivity study of the effects of CBT in OCD, and the first to test associations with follow-up clinical status. Results show functional network efficiency as a biomarker of CBT response and relapse in OCD. CBT increases network efficiency as it alleviates symptoms in most patients, but those entering therapy with already high network efficiency are at greater risk of relapse. Results have potential clinical implications for treatment selection.
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Jamie D
authors.initials: JD
authors.lastname: Feusner
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Teena
authors.initials: T
authors.lastname: Moody
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Tsz Man
authors.initials: TM
authors.lastname: Lai
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Courtney
authors.initials: C
authors.lastname: Sheen
authors.affiliation: Laureate Institute for Brain Research , Tulsa, OK , USA ; The University of Tulsa , Tulsa, OK , USA.
authors.forename: Sahib
authors.initials: S
authors.lastname: Khalsa
authors.affiliation: Department of Neurology, University of California San Francisco , San Francisco, CA , USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Brown
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Levitt
authors.affiliation: Department of Neurology, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Jeffry
authors.initials: J
authors.lastname: Alger
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles , Los Angeles, CA , USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: O'Neill
keywords: CBT; brain network; connectome; graph theory; resting-state fMRI