A randomized controlled trial of risperidone and olanzapine for schizophrenic patients with neuroleptic-induced tardive dyskinesia.
OBJECTIVE
To compare the efficacy of risperidone and olanzapine in schizophrenic patients with tardive dyskinesia on treatment with first-generation antipsychotics.


METHODS
We conducted a 24-week, rater-blinded, flexible-dose study. Sixty patients with DSM-IV schizophrenia (n = 58) or schizoaffective disorder (n = 2) met the DSM-IV research criteria for neuroleptic-induced tardive dyskinesia and were randomly assigned to a risperidone or olanzapine group. The primary outcome was a comparison of the change in the total scores on the Abnormal Involuntary Movement Scale (AIMS) from baseline to study end point between the groups. The study was conducted from July 2000 to June 2004.


RESULTS
The mean ± SD doses of risperidone and olanzapine from baseline to study end point were 1.9 ± 0.7 to 4.1 ± 1.4 mg/d and 8.1 ± 2.0 to 12.6 ± 5.4 mg/d, respectively. There were no statistically significant differences in demographic data, severity of tardive dyskinesia, or psychotic symptoms between risperidone and olanzapine groups at baseline assessment. Both groups showed significant improvement in mean ± SD AIMS total scores (risperidone: −7.4 ± 6.9, P < .0001; olanzapine: −6.2 ± 8.0, P = .0002). However, there was a more statistically significant change in the slope of AIMS total scores in the risperidone group than in the olanzapine group (P = .0001).


CONCLUSIONS
Our findings demonstrated that olanzapine may not have better potential for tardive dyskinesia improvement than risperidone did. Double-blinded, fixed dose studies with a larger sample size on schizophrenic patients with tardive dyskinesia from different ethnic groups are needed to confirm the results of our study.


BACKGROUND
clinicaltrials.gov Identifier NCT00621998
Chan
Hung-Yu
HY
Taoyuan Mental Hospital, Taoyuan County, Taiwan.
Chiang
Shu-Chuan
SC
Chang
Ching-Jui
CJ
Gau
Susan S-F
SS
Chen
Jiahn-Jyh
JJ
Chen
Chiung-Hsu
CH
Hwu
Hai-Gwo
HG
Lai
Mei-Shu
MS
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000009:adverse effects / Q000627:therapeutic use*; D010054:Brief Psychiatric Rating Scale; D004305:Dose-Response Relationship, Drug; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination / Q000187:drug effects; D000077152:Olanzapine; D011618:Psychotic Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use*; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D013624:Taiwan
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D018967:Risperidone; D000077152:Olanzapine