Neuropsychological Impairment in Tardive Dyskinesia

Abstract

Tardive dyskinesia (TD) is a movement disorder secondary to neuroleptic treatment. Whether TD is associated with neurocognitive dysfunction is a controversial issue. We reviewed 31 published studies evaluating neuropsychological (NP) test results in schizophrenic patients with and without TD and found that TD was generally reported to be associated with cognitive impairment. Numerous methodological limitations, however, restrict the conclusions made about the relationship between cognition and dyskinesia. We therefore undertook a study in which 143 schizophrenic patients were evaluated on a comprehensive NP test battery. On both global and learning deficit scores, TD patients demonstrated greater impairment than did a matched comparison group. Two aspects of TD (severity and topography) were related to severity of cognitive impairment. These findings suggest that dyskinesia and cognition may share some underlying mechanism in schizophrenia.