Risperidone and Olanzapine for the Schizophrenic Patients With Neuroleptic-Induced Tardive Dyskinesia

A Randomized Controlled Trial of Risperidone and Olanzapine for the Schizophrenic Patients With Neuroleptic-Induced Tardive Dyskinesia

We initiate a study with research grant from department of health and Taoyuan mental hospital and choose risperidone and olanzapine as study medications. We compare the effects of these 2 drugs in schizophrenic spectrum patients of Han ethnics with neuroleptic-induced tardive dyskinesia to test the hypothesis that these two medications have different effects in improving tardive dyskinesia.

Objective: First generation antipsychotics would induce tardive dyskinesia in some schizophrenic patients. Second generation antipsychotics were the choices for these patients. But which one of second generation antipsychotic was the better choice did not have definitive results. We compared risperidone and olanzapine in schizophrenic patients with neuroleptic-induced tardive dyskinesia to see their effects in improving tardive dyskinesia. We also collected the data of average dose of risperidone and olanzapine to help the dosing strategy guidelines for the schizophrenic patients with neuroleptic-induced tardive dyskinesia.

Method: This randomized, rater-blind, parallel group, flexible dose study enrolled patients from Taoyuan Mental Hospital from July 2000 to December 2003. Schizophrenia, schizophreniform or schizoaffective disorder (DSM-IV) patients who met the research criteria of neuroleptic-induced tardive dyskinesia research criteria of DSM-IV and no less than moderate severity (> or =4) of global impression of extrapyramidal syndrome rating scale (ESRS). 60 patients were random assignment to risperidone or olanzapine for 24 weeks. The primary outcome was to compare the change of total scores of abnormal involuntary movement scale from baseline to study endpoint.

Inclusion Criteria:

• Age of 18-70 y/o
• Female patients did not have pregnancy plans and must agree to use reliable pregnancy prevention methods if during childbearing age
• Meet schizophrenia, schizophreniform or schizoaffective disorder criteria of DSM-IV
• Fulfill DSM-IV neuroleptic-induced tardive dyskinesia research criteria, the severity of tardive dyskinesia was no less than moderate degree (> or =4) assessed by global impression of Extrapyramidal System Rating Scale (item 42 of ESRS)
• Patients or legal responsible people agree to join study and sign informed consent

Exclusion Criteria:

• Had other axis I diagnosis of DSM-IV
• Unstable major systemic diseases
• Had neurological disorder influenced to EPS assessment
• Substance abuse or dependence other then coffee or tobacco within 6 months before study