title: Patient characteristics and prescription patterns of atypical antipsychotics among patients with schizophrenia.
abstract: BACKGROUND
  Schizophrenia, one of the leading causes of disability, contributes substantially to the use of medical and mental health services. The treatment of schizophrenia is therefore particularly important to reduce deficits across a large number of neurocognitive domains.
  
  
  OBJECTIVE
  To describe the prescription (e.g. initiation and switching) patterns of atypical antipsychotic agents and examine the extent to which patient sociodemographic and clinical characteristics are associated with the prescription patterns of atypical antipsychotics among patients with schizophrenia.
  
  
  METHODS
  Using unique data sources from the Veterans Health Administration (VA), the study identified 89 107 patients with schizophrenia based on at least one inpatient or more than or equal to two outpatients' ICD-9-CM codes (> or =7 days apart). We defined a prior 6-month (1/1/99 to 6/30/99) and a post 6-month (7/1/99 to 12/31/99) period to describe patterns of initiation and switching of atypical antipsychotics.
  
  
  RESULTS
  Only a small number of patients were on clozapine (1.8%) and quetiapine (1.4%). More patients were prescribed olanzapine (23%) than risperidone (20%) (P < 0.001). Compared with patients who were on risperidone, those who were on olanzapine were younger (P < 0.001), more likely Hispanic (P < 0.001), more likely married (P < 0.05), had more service-connected disability (P < 0.001), had fewer numbers of physical comorbidities (P < 0.001), and a lower body mass index (BMI) (P < 0.05).
  
  
  CONCLUSIONS
  Olanzapine and risperidone appear to be prescribed to patients with different sociodemographic and clinical characteristics. Future research needs to explore the reasons for those differences.
authors.affiliation: Health Outcomes Technologies, Health Services Department, Boston University School of Public Health, Boston, MA, USA. xsren@bu.edu
authors.forename: X S
authors.initials: XS
authors.lastname: Ren
authors.forename: L E
authors.initials: LE
authors.lastname: Kazis
authors.forename: A F
authors.initials: AF
authors.lastname: Lee
authors.forename: A
authors.initials: A
authors.lastname: Hamed
authors.forename: Y H
authors.initials: YH
authors.lastname: Huang
authors.forename: F
authors.initials: F
authors.lastname: Cunningham
authors.forename: D R
authors.initials: DR
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D014150:Antipsychotic Agents / Q000008:administration & dosage*; D001569:Benzodiazepines; D003024:Clozapine / Q000008:administration & dosage; D003987:Dibenzothiazepines / Q000008:administration & dosage; D004363:Drug Utilization / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D010890:Pirenzepine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D000069348:Quetiapine Fumarate; D012042:Registries; D018967:Risperidone / Q000008:administration & dosage; D012559:Schizophrenia / Q000188:drug therapy* / Q000453:epidemiology* / Q000209:etiology; D017678:Sex Distribution; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology; D014493:United States Department of Veterans Affairs
chemical_list: D014150:Antipsychotic Agents; D003987:Dibenzothiazepines; D001569:Benzodiazepines; D000069348:Quetiapine Fumarate; D010890:Pirenzepine; D003024:Clozapine; D018967:Risperidone; D000077152:Olanzapine