The prevalence of tardive dystonia, tardive dyskinesia, parkinsonism and akathisia The Curaçao Extrapyramidal Syndromes Study: I.

A prevalence study of extrapyramidal syndromes was conducted among all psychiatric inpatients of the Netherlands Antilles (n = 194; mean age 53.1). The Netherlands Antilles are very suitable for epidemiological research as it is a well-defined catchment area with only one psychiatric hospital and a health care system based on western principles. In this mainly chronic population, the prevalence was measured of tardive dystonia, tardive dyskinesia, parkinsonism and akathisia using respectively the Fahn-Marsden rating scale, the Abnormal Involuntary Movement Scale, the Unified Parkinson Disease Rating Scale and the Barnes Akathisia Rating Scale. The prevalence numbers were for tardive dystonia 13.4%, tardive dyskinesia 39.7%, parkinsonism 36.1%, akathisia 9.3% and pseudoakathisia 12.9%. The most important conclusions were: (1) The prevalence of tardive dystonia was higher than reported in most other studies and (2) extrapyramidal syndromes are very common in this predominantly Negroid population, with three out of four patients suffering of one or more extrapyramidal syndromes.