Factors influencing the choice of new generation antipsychotic medication in the treatment of patients with schizophrenia.

Objective: This prospective, naturalistic study investigated the factors influencing physicians' choice of antipsychotic drug therapy in the treatment of patients with schizophrenia.

Method: 108 in- and outpatients treated at the Department of Psychiatry of the Medical University Innsbruck who started treatment with a new generation antipsychotic (except clozapine) were included. The following factors were investigated: sociodemographic and illness-related variables, pretreatment, the reasons for change of treatment (lack of efficacy, side effects, non-compliance), side effects of pretreatment and body-mass-index (BMI).

Results: Sociodemographic and most illness-related variables did not have an influence on the physicians' choice of medication. Risperidone was more frequently prescribed in patients with severe positive symptoms than amisulpride or quetiapine. Rigidity, orthostatic dizziness and gynecomastia during pretreatment were frequently associated with starting patients on ziprasidone. In patients with diminished sexual desire ziprasidone was preferred over olanzapine. Amisulpride was used more commonly than olanzapine if patients had experienced weight gain during pretreatment. Moreover, patients who were prescribed amisulpride had a significantly higher BMI in comparison to patients who were prescribed olanzapine. The reasons for current change of treatment, as well as the drug history (total number of antipsychotic drugs prescribed during the course of the illness) did not have an influence on the physicians' choice of antipsychotic.

Conclusion: In summary, the data suggest that side effects have a larger influence on the choice of antipsychotic than demographic or illness-related variables, except the severity of positive symptoms.