• Tardive dystonia;
  • tardive dyskinesia;
  • neuroleptics.

Abstract Nine tardive dystonia cases were compared with 13 tardive dyskinesia cases selected for the severity and persistence of their involuntary movements. Both groups were neurological referrals from an identical source. While advanced age and female preponderance were prominent features in tardive dyskinesia, onset in most tardive dystonia cases occurred in young adulthood, and the sex distribution showed a slight majority of males. Other differences in the dystonia group included gait abnormalities in four cases, lower tolerance of neuroleptic discontinuance, with the reappearance of psychoses, and a poorer prognosis for reversibility after follow-up. In fact, none of the dystonia patients reversed as opposed to seven of the tardive dyskinesia patients. In order to identify the full spectrum of tardive dystonia and exclude any referral bias, systematic epidemiological studies on psychiatric populations should include young adults of both sexes.