The prognosis of tardive dyskinesia.

Reexamination of the prognosis of tardive dyskinesia indicates that the concept of irreversibility should be replaced by a focus on longitudinal changes. Factors involved in the etiology and point prevalence of TD (e.g., neuroleptic exposure) are not necessarily the determinants of outcome. The presence of affective disorder and poor response to treatment in chronic psychotic patients appear to be related to poor prognosis. Severe dyskinesia with functional impairment is rare. Such severe cases are more likely to show a rapidly developing malignant course than to be the end result of slowly progressing TD after many years of neuroleptic treatment.