title: Metabolic differences between Asian and Caucasian patients on clozapine treatment.
abstract: OBJECTIVE
  To establish if there are ethnic differences in the various metabolic disturbances that are common with clozapine treatment.
  
  
  METHODS
  Forty subjects (20 Asians and 20 Caucasians) with a diagnosis of schizophrenia were recruited for the study. Clozapine blood levels as well as fasting blood glucose, lipid levels, and liver function tests were established. Other clinical parameters such as blood pressure and Body Mass Index (BMI) were recorded for each patient.
  
  
  RESULTS
  The mean clozapine dose was significantly higher in the Caucasian subjects (432.5+/-194.7 mg) as compared to the Asian subjects (175.6+/-106.9 mg) (p<0.001) while the mean weight-corrected dose for Asian patients was lower (3.0+/-1.9 and 5.0+/-2.1 mg/kg, respectively, p=0.005). There were, however, no ethnic differences in the mean plasma clozapine concentration (415.3+/-185.8 ng/ml in Caucasians and 417.1+/-290.8 ng/ml in Asians). BMI were significantly higher in Caucasians, as were the number of subjects with hypertension; levels of hepatic enzymes were higher in the Asian group.
  
  
  CONCLUSIONS
  Not only are there pharmacokinetic differences between Asian and Caucasian patients receiving clozapine, but there may also be differential emergence of certain metabolic abnormalities like hypertension and weight gain in these two ethnic groups. However, the effects of life style including diet and exercise cannot be excluded.
authors: Institute of Mental Health and Woodbridge Hospital, Singapore, and Department of Psychiatry, University of Melbourne, Richmond, Australia. Mythily@imh.com.sg
authors: Mythily
authors: M
authors: Subramaniam
authors: Chee
authors: C
authors: Ng
authors: Siow-Ann
authors: SA
authors: Chong
authors: Rathi
authors: R
authors: Mahendran
authors: Tim
authors: T
authors: Lambert
authors: Elaine
authors: E
authors: Pek
authors: Chan Yiong
authors: CY
authors: Huak
mesh_terms: D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000493:pharmacokinetics*; D044466:Asian People; D001219:Aspartate Aminotransferases / Q000097:blood; D001663:Bilirubin / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D003024:Clozapine / Q000009:adverse effects / Q000493:pharmacokinetics*; D004032:Diet; D005006:Ethnicity; D005260:Female; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D014280:Triglycerides / Q000097:blood; D044465:White People
chemical_list: D014150:Antipsychotic Agents; D001786:Blood Glucose; D014280:Triglycerides; D002784:Cholesterol; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D003024:Clozapine; D001663:Bilirubin