Comparative analysis of persistent dyskinesias of long-term usage with neuroleptics in France and in Japan.

The prevalence of tardive dyskinesia was studied in two psychiatric hospitals, one in France (Hopital psychiatrique de Bassens) and the other in Japan (Inogashire Hospital). Twenty-four of 131 patients in Bassens exhibited this disorder, and 22 of 123 patients in Inogashira. No difference was observed between the prevalence of both hospitals. Higher incidence in older age and a marked coexistence of chronic brain disorders were common characteristics of the patients affected by this disorder in both hospitals. All cases in France and in Japan presented a typical oral dyskinesia, but in general the symptoms in France were less intermittent and more pronounced than those in Japan. There existed a considerable contrast of the psychotropic medications between the two hospitals, which seemed to be related not to the prevalence, but to the severity of the symptoms.