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Clinical Trial
. 1999 Jan:174:23-30.
doi: 10.1192/bjp.174.1.23.

Randomised double-blind comparison of the incidence of tardive dyskinesia in patients with schizophrenia during long-term treatment with olanzapine or haloperidol

C M Beasley  1 , M A Dellva, R N Tamura, H Morgenstern, W M Glazer, K Ferguson, G D Tollefson
Affiliations
Clinical Trial

Randomised double-blind comparison of the incidence of tardive dyskinesia in patients with schizophrenia during long-term treatment with olanzapine or haloperidol

C M Beasley et al. Br J Psychiatry. 1999 Jan.

Abstract

Background: Tardive dyskinesia is important in the side-effect profile of antipsychotic medication.

Aims: The development of tardive dyskinesia was evaluated in patients treated with double-blind, randomly assigned olanzapine or haloperidol for up to 2.6 years.

Methods: Tardive dyskinesia was assessed by the Abnormal Involuntary Movement Scale (AIMS) and Research Diagnostic Criteria for Tardive Dyskinesia (RD-TD), it was defined as meeting RD-TD criteria at two consecutive assessments. The risk of tardive dyskinesia, the relative risk, incidence rate, and incidence rate ratio were estimated.

Results: The relative risk of tardive dyskinesia for the overall follow up period for haloperidol (n = 522) v. olanzapine (n = 1192) was 2.66 (95% CI = 1.50-4.70). Based on data following the initial six weeks of observation (during which patients underwent medication change and AIMS assessments as frequently as every three days), the one-year risk was 0.52% with olanzapine (n = 513) and 7.45% with haloperidol (n = 114). The relative risk throughout this follow-up period was 11.37 (95% CI = 2.21-58.60).

Conclusion: Our results indicated a significantly lower risk of tardive dyskinesia with olanzapine than with haloperidol.

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Comment in

  • Olanzapine and tardive dyskinesia.
    Woods SW. Woods SW. Br J Psychiatry. 1999 Oct;175:391-2. doi: 10.1192/bjp.175.4.391b. Br J Psychiatry. 1999. PMID: 10789313 No abstract available.