Spontaneous dyskinesia and parkinsonism in never-medicated, chronically ill patients with schizophrenia: 18-month follow-up

BACKGROUND: Spontaneous dyskinesia and parkinsonism have been reported in never-medicated patients with schizophrenia but there has been no previous study of the natural history of these conditions. AIMS: To determine the prevalence of spontaneous dyskinesia and parkinsonism in a group of never-medicated, chronically ill patients with schizophrenia on two occasions separated by an 18-month interval. METHOD: Dyskinesia was assessed by the Abnormal Involuntary Movements Scale using Schooler and Kane criteria for its presence; parkinsonism by the Simpson and Angus scale; and mental state by the Positive and Negative Syndrome Scale for schizophrenia. RESULTS: Thirty-seven patients were examined on two occasions. Nine (24%) had dyskinesia on both occasions, 12 (33%) on one occasion and 16 (43%) on neither occasion. Twenty-one (57%) had dyskinesia on at least one occasion. Thirteen patients (35%) had parkinsonism on at least one occasion. CONCLUSIONS: Spontaneous dyskinesia and parkinsonism fluctuate over time. The former was found on at least one occasion in the majority of patients. It is an integral part of the schizophrenic disease process.