title: Outcomes of medicaid beneficiaries with schizophrenia receiving clozapine only or antipsychotic combinations.
abstract: OBJECTIVE
  Patients with treatment-resistant schizophrenia commonly receive nonrecommended drug regimens, including antipsychotic polypharmacy, sometimes in lieu of clozapine. This analysis compared utilization and cost outcomes for cohorts of Medicaid beneficiaries treated with clozapine monotherapy and with antipsychotic polypharmacy.
  
  
  METHODS
  Data were from the Medicaid MarketScan database. Patients (age 18-64) initiated second-generation antipsychotic polypharmacy or clozapine monotherapy between July 2006 and January 2009, had continuous Medicaid coverage from six months before (preperiod) through 12 months after (postperiod) treatment initiation, and had a diagnosis of schizophrenic disorder (ICD-9-CM code 295.XX). Study outcomes included disease-specific and all-cause hospitalization, emergency department use, and Medicaid payments. Logistic regression analyses and generalized linear models controlled for demographic factors, preperiod utilization, and comorbidities.
  
  
  RESULTS
  Characteristics associated with use of clozapine monotherapy (N=479) instead of antipsychotic polypharmacy (N=2,440) included younger age, fewer comorbidities, lower preperiod utilization rates, nonwhite race, and male sex. When the analysis controlled for baseline differences, clozapine monotherapy was associated with lower odds of mental disorder-related (odds ratio [OR]=.75, 95% confidence interval [CI]=.60-.95) or schizophrenia-related (OR=.70, CI=.54-.90) emergency department use but not with hospitalization or all-cause emergency department use. Total Medicaid payments were significantly lower for the clozapine group than for the polypharmacy group: reductions of $21,315 for all-cause, $17,457 for mental disorder-related, and $10,582 for schizophrenia-related payments.
  
  
  CONCLUSIONS
  Among nonelderly adult Medicaid beneficiaries with schizophrenia, treatment with clozapine instead of antipsychotic polypharmacy was associated with reduced disease-specific emergency department use and with reduced disease-specific and all-cause health care costs.
authors.affiliation: Dr. Velligan is with the Department of Psychiatry, University of Texas Health Science Center at San Antonio. Dr. Carroll is with Xcenda, Charlotte, North Carolina, and completed work on this project while employed at Teva Pharmaceuticals, Kansas City, Missouri. Dr. Lage is with HealthMetrics Outcomes Research, Bonita Springs, Florida. Ms. Fairman is with Kathleen Fairman, LTD, Phoenix, Arizona. Send correspondence to Dr. Lage (e-mail: lagemj@hlthmetrics.com ).
authors.forename: Dawn I
authors.initials: DI
authors.lastname: Velligan
authors.forename: Cathy
authors.initials: C
authors.lastname: Carroll
authors.forename: Maureen J
authors.initials: MJ
authors.lastname: Lage
authors.forename: Kathleen
authors.initials: K
authors.lastname: Fairman
mesh_terms: D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D003024:Clozapine / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008484:Medicaid / Q000706:statistics & numerical data*; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D019338:Polypharmacy; D012189:Retrospective Studies; D012559:Schizophrenia / Q000188:drug therapy*; D014481:United States; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D003024:Clozapine