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Spontaneous movement disorders in antipsychotic-naive patients with first-episode psychoses: a systematic review

Published online by Cambridge University Press:  12 November 2008

S. Pappa  and
P. Dazzan
S. Pappa*
Affiliation:
Institute of Psychiatry, Division of Psychological Medicine, King's CollegeLondon, UK
P. Dazzan
Affiliation:
Institute of Psychiatry, Division of Psychological Medicine, King's CollegeLondon, UK
*
*Address for correspondence: S. Pappa, M.D., Ph.D., Consultant Psychiatrist and Honorary Research Associate, Department of Psychiatry, PO 63, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK. (Email: [email protected])
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Abstract

Background

Spontaneous movement disorders (SMDs), such as spontaneous dyskinesia and parkinsonism, have been described in patients with schizophrenia who have never been treated with antipsychotic medication. Their presence has been documented extensively in chronic schizophrenia but not at the time of illness onset.

Method

We performed a systematic review of studies investigating spontaneous abnormal movements elicited on clinical examination in antipsychotic-naive patients with first-episode psychosis.

Results

We identified a total of 13 studies. Findings suggest a spontaneous dyskinesia median rate of 9% and a spontaneous parkinsonism median rate of 17%. Information on akathisia and dystonia was limited. The presence of SMDs may be associated with negative symptoms and cognitive dysfunction.

Conclusions

These findings support the notion that spontaneous abnormal movements are part of a neurodysfunction intrinsic to the pathogenesis of schizophrenia. Future studies should further investigate the role of basal ganglia and extrapyramidal pathways in the pathophysiology of psychosis, with particular attention to treatment implications.

Keywords

Antipsychotic-naivefirst-episode psychosisspontaneous dyskinesiaspontaneous movement disorders
Type
Review Article
Information
Psychological Medicine , Volume 39 , Issue 7 , July 2009 , pp. 1065 - 1076
Copyright
Copyright © 2008 Cambridge University Press

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