title: Antipsychotic response in delusional disorder and schizophrenia: a prospective cohort study.
abstract: BACKGROUND
  Scientific evidence focused on the treatment response in delusional disorder (DD) patients is scarce, and the findings are controversial. Our goal was to compare the antipsychotic response at the 12-week followup between patients diagnosed with DD and patients diagnosed with schizophrenia and to identify potential response dimensions.
  
  
  METHODS
  A prospective, observational, cohort study with 12-week follow-up was conducted with DD and schizophrenia patients matched for sex, age and cumulative years of disease. The following scales were assessed: Positive and Negative Syndrome Scale (PANSS; 5-factors), Personal and Social Performance Scale (PSP), Clinical Global Impression Scale (CGI), and Columbia-Suicide Severity Rating Scale (C-SSRS). Treatment response was defined as a &#8805;30% reduction in the total PANSS score. Linear and logistic regression models were used to investigate the potential predictive value of psychopathological variables for the antipsychotic response.
  
  
  RESULTS
  Response percentages in DD and schizophrenia were 61.5% and 69.2%, respectively. The duration of untreated psychosis, antipsychotic dosage, and diagnosis did not predict antipsychotic response. In the whole sample, improvement in positive symptoms was significantly associated with the clinical global improvement (p=0.006), explaining almost 20% of the variance in the model. Within the DD group, improvement in cognitive symptoms explained 30% of the variance in clinical global improvement.
  
  
  CONCLUSIONS
  Both response percentages and required antipsychotic doses were similar between DD and schizophrenia. Changes in positive symptoms were associated with clinical global improvement in the entire sample, and improvement in cognitive symptoms was correlated with global improvement exclusively in DD.
authors.affiliation: Barcelona Clinic Schizophrenia Unit (BCSU). Neuroscience Institute. Hospital Clínic of Barcelona. Department of Psychiatry and Clinical Psychobiology. University of Barcelona. Barcelona, Spain.
authors.forename: Alexandre
authors.initials: A
authors.lastname: González-Rodríguez
authors.affiliation: Barcelona Clinic Schizophrenia Unit (BCSU). Neuroscience Institute. Hospital Clínic of Barcelona. University of Barcelona. CIBERSAM, IDIBAPS. Barcelona, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Catalán
authors.affiliation: Barcelona Clinic Schizophrenia Unit (BCSU). Neuroscience Institute. Hospital Clínic of Barcelona. University of Barcelona. CIBERSAM, IDIBAPS. Barcelona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Penadés
authors.affiliation: Neuroscience Institute. Hospital Clinic of Barcelona. Barcelona, Spain.
authors.forename: Victoria
authors.initials: V
authors.lastname: Ruiz
authors.affiliation: Biochemistry and Molecular Genetics Department. Hospital Clinic of Barcelona. University of Barcelona. Barcelona, Spain.
authors.forename: Mercè
authors.initials: M
authors.lastname: Torra
authors.affiliation: Barcelona Clinic Schizophrenia Unit (BCSU). Neuroscience Institute. Hospital Clínic of Barcelona. University of Barcelona. CIBERSAM, IDIBAPS. Barcelona, Spain.
authors.forename: Miquel
authors.initials: M
authors.lastname: Bernardo
mesh_terms: D014150:Antipsychotic Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012559:Schizophrenia / Q000188:drug therapy*; D012563:Schizophrenia, Paranoid / Q000188:drug therapy; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents