title: Comparative Effectiveness of Clozapine and Standard Antipsychotic Treatment in Adults With Schizophrenia.
abstract: OBJECTIVE
  The authors compared the effectiveness of initiating treatment with either clozapine or a standard antipsychotic among adults with evidence of treatment-resistant schizophrenia in routine clinical practice.
  
  
  METHODS
  U.S. national Medicaid data from 2001 to 2009 were used to examine treatment outcomes in a cohort of patients with schizophrenia and evidence of treatment resistance that initiated clozapine (N=3,123) and in a propensity score-matched cohort that initiated a standard antipsychotic (N=3,123). Interventions were new initiation of clozapine or a standard antipsychotic medication, defined as no exposure to the new medication in the prior 365 days. The primary outcome was hospital admission for a mental disorder. Secondary outcomes included discontinuation of the index antipsychotic, use of an additional antipsychotic, incidence of serious medical conditions, and mortality.
  
  
  RESULTS
  Initiation of clozapine was associated with a significantly decreased rate of psychiatric hospital admission (hazard ratio=0.78, 95% CI=0.69-0.88), index antipsychotic discontinuation (hazard ratio=0.60, 95% CI=0.55-0.65), and use of an additional antipsychotic (hazard ratio=0.76, 95% CI=0.70-0.82). Clozapine was associated with significantly increased incidence of diabetes mellitus (2.8% for clozapine vs. 1.4% for standard antipsychotic; hazard ratio=1.63, 95% CI=0.98-2.70), hyperlipidemia (12.9% for clozapine vs. 8.5% for standard antipsychotic; hazard ratio=1.40, 95%CI=1.09-1.78), and intestinal obstruction (0.9% for clozapine vs. 0.3% for standard antipsychotic; hazard ratio=2.50, 95% CI=0.97-6.44).
  
  
  CONCLUSIONS
  In adults with schizophrenia and evidence of treatment resistance, initiating clozapine compared with initiating a standard antipsychotic was associated with greater effectiveness on several important outcomes. Increasing the judicious use of clozapine is warranted together with vigilance to prevent and detect serious medical adverse effects.
authors.affiliation: From the Department of Psychiatry, Columbia University, and the New York State Psychiatric Institute, New York; and the Institute for Health, Health Care Policy and Aging Reearch, Rutgers University, New Brunswick, N.J.
authors.forename: T Scott
authors.initials: TS
authors.lastname: Stroup
authors.affiliation: From the Department of Psychiatry, Columbia University, and the New York State Psychiatric Institute, New York; and the Institute for Health, Health Care Policy and Aging Reearch, Rutgers University, New Brunswick, N.J.
authors.forename: Tobias
authors.initials: T
authors.lastname: Gerhard
authors.affiliation: From the Department of Psychiatry, Columbia University, and the New York State Psychiatric Institute, New York; and the Institute for Health, Health Care Policy and Aging Reearch, Rutgers University, New Brunswick, N.J.
authors.forename: Stephen
authors.initials: S
authors.lastname: Crystal
authors.affiliation: From the Department of Psychiatry, Columbia University, and the New York State Psychiatric Institute, New York; and the Institute for Health, Health Care Policy and Aging Reearch, Rutgers University, New Brunswick, N.J.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Huang
authors.affiliation: From the Department of Psychiatry, Columbia University, and the New York State Psychiatric Institute, New York; and the Institute for Health, Health Care Policy and Aging Reearch, Rutgers University, New Brunswick, N.J.
authors.forename: Mark
authors.initials: M
authors.lastname: Olfson
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D003024:Clozapine / Q000627:therapeutic use*; D015331:Cohort Studies; D016208:Databases, Factual; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D006949:Hyperlipidemias / Q000453:epidemiology; D007415:Intestinal Obstruction / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008484:Medicaid; D008605:Mental Health Services / Q000706:statistics & numerical data*; D008875:Middle Aged; D016016:Proportional Hazards Models; D011618:Psychotic Disorders / Q000188:drug therapy*; D012189:Retrospective Studies; D012559:Schizophrenia / Q000188:drug therapy*; D016896:Treatment Outcome; D014481:United States
chemical_list: D014150:Antipsychotic Agents; D003024:Clozapine