title: A prospective study of impairment in glucose control caused by clozapine without changes in insulin resistance.
abstract: OBJECTIVE
  This prospective study examines the effect of clozapine on glucose control and insulin sensitivity.
  
  
  METHODS
  Glucose homeostasis was measured in nine female and 11 male patients with schizophrenia (mean age=30.5 years, SD=7.4) before clozapine treatment and after a mean of 2.5 months (SD=0.95) of clozapine treatment. Oral glucose tolerance and insulin levels were measured. Insulin resistance level was measured by the homeostasis model assessment.
  
  
  RESULTS
  Eleven (55%) of the patients developed abnormal glucose control; the mean age of these patients was 30.2 (SD=7.1), and five were women. Patients' insulin resistance at baseline (mean insulin resistance level=3.88, SD=2.93) was unaffected by clozapine. Mean fasting and 2-hour glucose levels significantly increased by 0.55 mmol/liter and 1.4 mmol/liter, respectively. There was no correlation between change in body mass index and change in fasting glucose levels.
  
  
  CONCLUSIONS
  Clozapine impairs glucose control within 4 months of treatment, independent of changes in insulin sensitivity and body mass index.
authors.affiliation: Division of Psychological Medicine, Insitute of Psychiatry, London, UK. sphaoah@iop.kcl.ac.uk
authors.forename: Oliver D
authors.initials: OD
authors.lastname: Howes
authors.forename: Ajay
authors.initials: A
authors.lastname: Bhatnagar
authors.forename: Fiona P
authors.initials: FP
authors.lastname: Gaughran
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Amiel
authors.forename: Robin M
authors.initials: RM
authors.lastname: Murray
authors.forename: Lyn S
authors.initials: LS
authors.lastname: Pilowsky
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects*; D001786:Blood Glucose / Q000187:drug effects*; D015992:Body Mass Index; D003024:Clozapine / Q000009:adverse effects*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000139:chemically induced*; D011446:Prospective Studies; D012559:Schizophrenia / Q000188:drug therapy*; D012720:Severity of Illness Index
chemical_list: D014150:Antipsychotic Agents; D001786:Blood Glucose; D003024:Clozapine