The burden of tardive dyskinesia secondary to antipsychotic medication use among patients with mental disorders.

Objective: To assess the impact of developing tardive dyskinesia (TD), both with and without other pre-existing extrapyramidal symptoms (EPS), on healthcare resource utilization (HRU) among patients with mental disorders receiving antipsychotic medications. Methods: Data on patients receiving antipsychotics who had schizophrenia, major depressive disorder or bipolar disorder were extracted from a Medicaid claims database. Separate cohorts of TD patients with and without other EPS ("TD + EPS" and "TD non-EPS") were constructed and matched to patients in a non-TD/EPS control cohort at a ∼1:5 ratio. HRU outcomes were assessed using descriptive statistics and difference-in-differences techniques over baseline and follow-up periods defined as the 6 months before and after TD development, respectively. Results: The TD + EPS (n = 289) and TD non-EPS (n = 394) cohorts were matched with 1398 and 1922 control patients, respectively. The percentage of patients with all-cause and mental-disorder-related inpatient admissions increased from baseline to follow-up in the TD + EPS (12.8% and 12.5%, respectively) and TD non-EPS (16.0% and 13.5%) cohorts; by contrast, slight decreases (∼3%) in these outcomes were observed in the matched controls. Difference-in-differences analyses demonstrated that development of TD was associated with a statistically significant increase of ∼15-19% in the percentage of patients with all-cause and mental-disorder-related inpatient admissions/visits. The within-cohort change from baseline to follow-up in the use of potential drugs for TD or EPS was similar between the TD cohorts and their matched controls. Conclusions: This study demonstrates a significant economic burden associated with developing TD, as captured by increased HRU including inpatient admissions and ER visits.