Persistent tardive dyskinesia in bipolar patients.

The prevalence and outcome of persistent tardive dyskinesia (TD) was studied in 131 bipolar patients. There were 34 cases of persistent TD in the subgroup (n = 96) with a history of neuroleptic treatment (prevalence, 35.4%; 95% confidence interval, 25% to 45%); there were no cases of persistent TD in the subgroup (n = 35) without such treatment history. Except in one patient, signs of TD persisted in spite of lithium carbonate treatment in 23 patients (median duration, 16 months; range, five to 24 months), of whom 15 remained off of a neuroleptic regimen during the study period for a median duration of 14 months (range, four to 24 months). Using multiple regression analysis, two variables were found to predict the presence of persistent TD and account for 36% of the variance: longer cumulative duration of maintenance neuroleptic treatment and shorter duration of previous lithium carbonate treatment. There appears to be a significant risk of persistent TD among neuroleptic-treated bipolar patients. High-risk subgroups within this category need to be identified.