The prevalence of tardive dyskinesia in neuroleptic-treated diabetics. A controlled study.

In a controlled study, we compared the prevalence of tardive dyskinesia in 38 neuroleptic-treated diabetics with the prevalence of tardive dyskinesia in a group of 38 nondiabetic neuroleptic-treated controls, matched for age, sex, psychiatric diagnosis, and dose and duration of neuroleptic treatment. Members of each group were evaluated for movement disorders by a rater who used standard rating scales and was "blind" to all diagnoses and treatments. Neuroleptic-treated diabetics had a significantly higher prevalence and severity of tardive dyskinesia. There were no differences between groups on other possible risk factors for tardive dyskinesia, including parkinsonism, anticholinergic drug treatment, or cognitive function. These data suggest that diabetes mellitus should be examined further as a risk factor for tardive dyskinesia.