title: Obsessive-Compulsive Symptoms in Schizophrenia and in Obsessive-Compulsive Disorder: Differences and Similarities.
abstract: A growing literature suggests that obsessive-compulsive (OC) phenomena represent a distinct dimension in schizophrenia, independent of nuclear psychotic symptoms. Nevertheless, the OC psychopathologic profile in schizophrenia, compared with "pure" obsessive-compulsive disorder (OCD), has not yet been investigated extensively. This study investigated the clinical features of the OC dimension in patients with schizophrenia compared with patients with pure OCD.
  
  
  
  The main psychopathologic features of obsessions and compulsions were rated in 35 patients with schizophrenia and 31 patients with OCD, using the Structured Clinical Interview for DSM-IV Axis I Disorders, the Positive and Negative Syndrome Scale, the Yale-Brown Obsessive-Compulsive Scale, and the Leyton Obsessional Inventory.
  
  
  
  OC phenomena were indistinguishable in terms of their severity, resistance, interference, and control in both groups. However, patients with OCD showed higher rates of aggressive, contamination-related, sexual, and somatic themes; moreover, in the group with schizophrenia, a positive relationship was found between washing compulsions and delusions and between hoarding obsessions and delusions.
  
  
  
  These results indicate that patients with schizophrenia exhibit a narrower range of obsessive content compared with patients with OCD; in addition, OC and delusional themes tend to be related in schizophrenia as a unique symptomatic phenomenon.
authors.affiliation: TONNA, OTTONI, PAGLIA, OSSOLA, DE PANFILIS, and MARCHESI: Department of Neuroscience, Psychiatric Unit, University of Parma, Parma, ItalyTONNA, MONICI, DE PANFILIS, and MARCHESI: Department of Mental Health, Local Health Service, Parma, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Tonna
authors.forename: Rebecca
authors.initials: R
authors.lastname: Ottoni
authors.forename: Francesca
authors.initials: F
authors.lastname: Paglia
authors.forename: Alberto
authors.initials: A
authors.lastname: Monici
authors.forename: Paolo
authors.initials: P
authors.lastname: Ossola
authors.forename: Chiara
authors.initials: C
authors.lastname: DE Panfilis
authors.forename: Carlo
authors.initials: C
authors.lastname: Marchesi
mesh_terms: D003702:Delusions; D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000503:physiopathology*; D011599:Psychopathology; D012559:Schizophrenia / Q000175:diagnosis / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012720:Severity of Illness Index