Laterality of appendicular tardive dyskinesia in chronic schizophrenia

The notion that the neuropathology of schizophrenia is lateralized is supported, in part, by findings of asymmetries in tardive dyskinesia (TD). To verify the existence of asymmetric TD, this study used the AIMS examination to look for lateralization of limb movements in a sample of 58 patients with TD. Patients with schizophrenia were compared with patients with affective and schizoaffective disorders. Asymmetry was seen in the majority of patients, regardless of psychiatric diagnosis. There was no preference for one side over the other. In a subgroup of 16 patients rates repeatedly over 13 weeks, the presence and sidedness of asymmetry fluctuated. At least four ratings were needed to accurately predict the presence and sidedness of "persistent" asymmetry. This study does not support the notion that there is a consistent, lateralized asymmetry of TD in patients with schizophrenia. Moreover, it raises questions about the reliability of assessment of persistent laterality in TD using a single exam.