Despite comparable antipsychotic exposure, some patients experience involuntary movements yet others do not. Negative symptoms have been associated with tardive dyskinesia, but it is not certain that this is an association with primary negative symptoms.

To determine whether patients with deficit schizophrenia (who have primary negative symptoms) are more likely to experience tardive dyskinesia than those with non-deficit schizophrenia.

In 2006 all the people with a clinical diagnosis of schizophrenia in Nithsdale, South West Scotland, were identified using the ‘key informant’ method. These patients were assessed using the Schedule for the Deficit Syndrome (SDS) and for the presence of dyskinesia using the Abnormal Involuntary Movements Scale (AIMS). Patients were also assessed for akathisia using the Barnes-Akathisia Scale and for extrapyramidal side effects using the Simpson and Angus rating scale.

There is a significant association between deficit and TD when controlling for age. Those with tardive dyskinesia are more likely to have deficit schizophrenia. The odds ratio is 3.08 (95% CI 1.28, 7.37), p = 0.012.

Our findings support the proposal that the pathological process underlying deficit schizophrenia can predispose to the development of tardive dyskinesia.