title: Augmenting serotonin reuptake inhibitors in obsessive-compulsive disorder: What moderates improvement?
abstract: OBJECTIVE
  Patients with obsessive-compulsive disorder (OCD) often only partially respond to serotonin reuptake inhibitors (SRIs). In such cases, American Psychiatric Association practice guidelines suggest augmenting SRIs with cognitive-behavioral therapy consisting of exposure and ritual prevention (EX/RP) or antipsychotic medication (i.e., risperidone). We examined moderators and predictors of these 2 augmentation strategies.
  
  
  METHODS
  Data came from a randomized controlled trial that compared adding EX/RP or risperidone to SRIs in adults with OCD. Patients entered the study on a stable SRI dosage and were randomized to EX/RP (N = 40), risperidone (N = 40), or placebo (N = 20). Data were analyzed using multilevel modeling.
  
  
  RESULTS
  Pretreatment OCD severity, age, and depression were significant moderators. Although OCD severity was unrelated to EX/RP response, individuals with more severe OCD had poorer outcomes and slower improvement with risperidone. Increasing age predicted better response to risperidone, but not EX/RP. Increased depression predicted poorer response to placebo, but not EX/RP or risperidone. Poorer functioning predicted worse outcome across all 3 conditions. Together, these moderators and predictor accounted for 33% of the variance in outcomes, above and beyond the 30.8% accounted for by treatment condition.
  
  
  CONCLUSIONS
  SRI augmentation with EX/RP was more effective than risperidone across all of the demographic and clinical variables tested. EX/RP's superiority over risperidone increased with baseline OCD severity and with younger age. These data indicate that EX/RP should be the recommended SRI augmentation strategy, even for severe OCD. What determines the degree of EX/RP response in individual patients deserves further study.
authors.affiliation: Anxiety Disorders Clinic.
authors.forename: Michael G
authors.identifier: 0000-0002-7465-7879
authors.initials: MG
authors.lastname: Wheaton
authors.affiliation: Department of Psychology, Southern Methodist University.
authors.forename: David
authors.initials: D
authors.lastname: Rosenfield
authors.affiliation: Department of Psychiatry, University of Pennsylvania.
authors.forename: Edna B
authors.initials: EB
authors.lastname: Foa
authors.affiliation: Anxiety Disorders Clinic.
authors.forename: H Blair
authors.initials: HB
authors.lastname: Simpson
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D015928:Cognitive Behavioral Therapy; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000188:drug therapy / Q000523:psychology / Q000628:therapy*; D018967:Risperidone / Q000627:therapeutic use*; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D018967:Risperidone; D017367:Selective Serotonin Reuptake Inhibitors