Abstract
Objective
To establish if there are ethnic differences in the various metabolic disturbances that are common with clozapine treatment.
Method
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 (432.5βΒ±β194.7βmg) as compared to the Asian subjects (175.6βΒ±β106.9βmg) (pβ<β0.001) while the mean weightβcorrected dose for Asian patients was lower (3.0βΒ±β1.9 and 5.0βΒ±β2.1βmg/kg, respectively, pβ=β0.005). There were, however, no ethnic differences in the mean plasma clozapine concentration (415.3βΒ±β185.8βng/ml in Caucasians and 417.1βΒ±β290.8βng/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. Copyright Β© 2007 John Wiley & Sons, Ltd.