Nithsdale Schizophrenia Surveys 23: movement disorders. 20-year review.

Background: In the past 10 years the new atypical antipsychotic drugs have stimulated further interest in the pharmacological management of schizophrenia. The risk of movement disorders has been reported to be less with these new agents.

Aims: To examine the current prevalence of movement disorders among all people with schizophrenia in a discrete geographical area, to compare the prevalence in patients receiving and not receiving atypical antipsychotic drugs; and to compare current prevalence with prevalence over the past 20 years.

Method: In Nithsdale, south-west Scotland, in 1999/2000, we replicated previous studies by using the Abnormal Involuntary Movements Scale, Simpson-Angus scale and Barnes Akathisia Rating Scale to measure tardive dyskinesia, parkinsonism and akathisia, respectively. Mental state was assessed by the Positive and Negative Syndrome Scale.

Results: In 136 patients the prevalence of probable tardive dyskinesia was 43%, of parkinsonism 35% and of akathisia 15%. Parkinsonism was present as often in those receiving atypicals as in those receiving standard oral antipsychotics. The prevalence of tardive dyskinesia has doubled over 20 years.

Conclusions: Movement disorders remain significant problems for patients despite the introduction of atypical antipsychotic drugs.