title: Delusional disorders--are they simply paranoid schizophrenia?
abstract: OBJECTIVE
  This article tries to give an answer to the question of whether International Classification of Diseases (ICD-10) persistent delusional disorder (PDD) or Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) delusional disorder (DD) is simply paranoid schizophrenia (PS). Because ICD-10 PDD and DSM-IV DD are identical, we use DD as a synonym.
  
  
  METHODS
  A prospective and longitudinal study compared all inpatients with DD treated at the Halle-Wittenberg university hospital during a 14-year period with a previously investigated selected cohort of patients with PS. Sociodemographic data, symptomatology, course, and outcome parameters were examined using standardized instruments. The duration of the follow-up period in patients with DD was 10.8 years and for the PS patients 12.9 years.
  
  
  RESULTS
  Significant differences between DD and PS were found: DD patients are, in comparison to patients with PS, significantly older at onset. Less of their first-degree relatives have mental disorders. They less frequently come from a broken home situation. First-rank symptoms, relevant negative symptoms, and primary hallucinations did not occur in patients with DD. Patients with DD were less frequently hospitalized, and the duration of their hospitalization was shorter. Their outcome is much better regarding employment, early retirement due to the disorder, and psychopharmacological medication. They more often had stable heterosexual partnerships and were autarkic. They had lower scores in the Disability Assessment Scale and in Positive and Negative Syndrome Scale. The diagnosis of DD is very stable over time.
  
  
  CONCLUSIONS
  The findings of this study support the assumption that DDs are a separate entity and only exceptionally can be a prodrome of schizophrenia.
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, Martin Luther University of Halle-Wittenberg, Julius-Kühn-Strasse 7, 06097 Halle/Saale, Germany. andreas.marneros@medizin.uni-halle.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Marneros
authors.forename: Frank
authors.initials: F
authors.lastname: Pillmann
authors.forename: Tobias
authors.initials: T
authors.lastname: Wustmann
mesh_terms: D000328:Adult; D000367:Age Factors; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D012563:Schizophrenia, Paranoid / Q000145:classification* / Q000175:diagnosis* / Q000191:economics; D012737:Sex Factors