BACKGROUND It was hypothesised that schizophrenic patients with tardive dyskinesia show an excess of neurodevelopmental disturbance, particularly minor physical anomalies, in association with cognitive dysfunction and abnormalities of cerebral structure.
METHOD Forty-seven out-patients with a DSM-III diagnosis of schizophrenia were examined for tardive dyskinesia using the Abnormal Involuntary Movement Scale; they were examined also for minor physical anomalies and neuropsychological test performance. Cortical atrophy, signal hyperintensities and lateral ventricular volume were determined on magnetic resonance imaging.
RESULTS Patients with and without tardive dyskinesia could not be distinguished by age, gender distribution or a number of clinical measures; however, patients with tardive dyskinesia sorted fewer categories on the Wisconsin Card Sorting Test (P = 0.04). Cerebral structure in patients with and without tardive dyskinesia could not be distinguished on magnetic resonance imaging but those with dyskinesia, all of whom showed involvement of the orofacial region, showed more evident minor physical anomalies of the head relative to those of the periphery (P = 0.02).
CONCLUSIONS Tardive orofacial dyskinesia in schizophrenia appears to be associated particularly with poorer frontal lobe function, while predominance of craniofacial dysmorphogenesis may constitute a vulnerability factor that is related to the early origins of the disease process.