To assess the effects of clozapine, olanzapine and haloperidol on cholesterol triglycerides and glucose levels in aggressive schizophrenic patients. To determine whether changes in cholesterol are related to aggression.

100 physically aggressive schizophrenics were assigned to a randomized, double-blinded, parallel-group, 12-week treatment. There were 33, 34, and 33 subjects in the clozapine, olanzapine, and haloperidol groups, respectively. Fasting cholesterol, triglycerides and glucose were collected at baseline and at end of study. All aggressive events were recorded.

95 patients provided blood samples. There were differences among the three medications in weight change (F=7.6, df=2,93; p<.001), with greater weight gain for clozapine and olanzapine than haloperidol. There were significant differences among the 3 groups in changes in cholesterol (F=4.5, df=2,93; p=.01; greater increase for clozapine than for haloperidol, p <.01), triglycerides (F=5.5, df=2,93; p<.01; greater increase in clozapine than haloperidol, p <.01 and olanzapine p=.01) and glucose (F=3.9, df=2,93; p=.02; greater increase for clozapine than for haloperidol, p <.01 and than olanzapine, p=.05). We investigated the relationship to aggression, by dividing patients into high and low cholesterol groups through a median split. Patients in the low cholesterol group were more physically aggressive during the study than those in the high group (F=4.94, df=2,92, p=.03). A significantly higher percentage of the patients in the haloperidol group than in the clozapine group had values below the median.

Clozapine treatment is associated with increases in serum glucose, triglycerides and cholesterol. This increase in cholesterol may explain in part its antiaggressive effect.