title: Differential effects of risperidone, olanzapine, clozapine, and conventional antipsychotics on type 2 diabetes: findings from a large health plan database.
abstract: BACKGROUND
  Case series suggest that some antipsychotics may induce or exacerbate type 2 diabetes. This study measured the association of antipsychotic treatments with diabetes at a population level.
  
  
  METHODS
  Claims data for psychosis patients (ICD-CM-9 290.xx-299.xx) within health plans encompassing 2.5 million individuals were analyzed. Patients reporting preexisting type 2 diabetes up to 8 months prior to observation were excluded. The frequency of newly reported type 2 diabetes in untreated patients and among patients treated with antipsychotics from 5 categories (risperidone, olanzapine, clozapine, and high-potency and low-potency conventionals) was compared. Logistic regression models compared the odds of diabetes based on exposure to each of the antipsychotic categories.
  
  
  RESULTS
  Based on 12 months of exposure, the odds of type 2 diabetes for risperidone-treated patients (odds ratio = 0.88, 95% CI = 0.372 to 2.070) was not significantly different from that for untreated patients, whereas patients receiving other antipsychotics had a significantly greater risk of diabetes than untreated patients (p < .05): olanzapine, 3.10 (95% CI = 1.620 to 5.934); clozapine, 7.44 (95% CI = 0.603 to 34.751); high-potency conventionals, 2.13 (95% CI = 1.097 to 4.134); and low-potency conventionals, 3.46 (95% CI = 1.522 to 7.785). Older age and greater use of non-antipsychotic psychotropic medications also contributed to risk of type 2 diabetes. Olanzapine also showed significantly higher (p < .01) odds of diabetes associated with increasing dose.
  
  
  CONCLUSIONS
  Consistent with previously published literature, these data suggest that olanzapine, clozapine, and some conventional antipsychotics appear to increase the risk of acquiring or exacerbating type 2 diabetes and that the effect may vary by drug. In contrast to these agents, risperidone was not associated with an increased risk of type 2 diabetes.
authors.affiliation: HECON Associates, Montgomery Village, MD 20886, USA. fgian1708@aol.com
authors.forename: Frank D
authors.initials: FD
authors.lastname: Gianfrancesco
authors.forename: Amy L
authors.initials: AL
authors.lastname: Grogg
authors.forename: Ramy A
authors.initials: RA
authors.lastname: Mahmoud
authors.forename: Ruey-hua
authors.initials: RH
authors.lastname: Wang
authors.forename: Henry A
authors.initials: HA
authors.lastname: Nasrallah
mesh_terms: D000208:Acute Disease; D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001569:Benzodiazepines; D003024:Clozapine / Q000009:adverse effects* / Q000627:therapeutic use; D015897:Comorbidity; D016001:Confidence Intervals; D019992:Databases as Topic / Q000706:statistics & numerical data; D003924:Diabetes Mellitus, Type 2 / Q000139:chemically induced* / Q000175:diagnosis / Q000453:epidemiology*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007345:Insurance Claim Review / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D000077152:Olanzapine; D010890:Pirenzepine / Q000009:adverse effects* / Q000031:analogs & derivatives* / Q000627:therapeutic use; D011618:Psychotic Disorders / Q000188:drug therapy* / Q000453:epidemiology; D012307:Risk Factors; D018967:Risperidone / Q000009:adverse effects* / Q000627:therapeutic use; D014481:United States / Q000453:epidemiology
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D010890:Pirenzepine; D003024:Clozapine; D018967:Risperidone; D000077152:Olanzapine