An Experimental Study to Assess the Professional and Social Consequences of Tardive Dyskinesia

Analysis of Antipsychotic Dosage in Patients With Tardive Dyskinesia: A Case-Control Study Using the Claims Database of the Corporate Health Insurance Association

PURPOSE

This study aimed to assess the association between antipsychotic doses and the risk of tardive dyskinesia (TD) in clinical practice using a Japanese claims database from 2010 to 2020.

METHODS

The study population included patients 15 years or older with a diagnosis record of schizophrenia, depression, or bipolar disorder who were prescribed antipsychotics. Using a case-control design, we categorized patients newly diagnosed with TD as cases, with corresponding 1:10 matching in the control group. The primary endpoint was the relative risk of TD in the >median dose and ≤median dose groups, as determined using conditional logistic regression analysis adjusted for age.

RESULTS

The analysis population included 58,452 patients, and the median daily antipsychotic dose was 75 mg/d of chlorpromazine equivalent (CPZE). Of these, 80 were identified as TD cases, and doses >75 mg/d were associated with a significantly increased risk of TD at the last prescription and the maximum dose, respectively, before the date of the first diagnosis of TD. Post-hoc analysis further showed a significant association between doses ≥300 mg/d and the risk of TD compared to doses ≤75 mg/d and doses >75 to <300 mg/d. Comparing ≥300 mg/d versus >75 to <300 mg/d, the odd ratios at the last prescription and maximum dose before the first diagnosis of TD were 3.40 and 3.50, respectively.

CONCLUSIONS

In the Japanese medical claims database of patients receiving relatively low doses of antipsychotics, doses >75 mg/d were associated with an increased risk of TD in a dose-dependent manner.

A new era in the diagnosis and treatment of tardive dyskinesia

Tardive dyskinesia (TD) is a heterogeneous, hyperkinetic movement disorder induced by dopamine-receptor blocking agents that presents a unique challenge in the treatment of psychosis. Although acceptance of TD as a serious consequence of antipsychotic treatment was resisted initially, subsequent research by many investigators in psychopharmacology contributed to a rich store of knowledge on many aspects of the disorder. While basic neuroscience investigations continue to deepen our understanding of underlying motor circuitry, past trials of potential treatments of TD focusing on a range of theoretical targets were often inconclusive. Development of newer antipsychotics promised to reduce the risk of TD compared to older drugs, but their improved tolerability unexpectedly enabled an expanding market that paradoxically both increased the absolute number of patients at risk and diminished attention to TD which was relegated to legacy status. Fortunately, development and approval of novel vesicular monoamine transporter inhibitors offered evidence-based symptomatic treatment of TD for the first time and rekindled interest in the disorder. Despite recent progress, many questions remain for future research including the mechanisms underlying TD, genetic predisposition, phenomenological diversity, whether new cases are reversible, how to implement best practices to prevent and treat TD, and whether the development of novel antipsychotics free of the risk of TD is attainable. We owe our patients the aspirational goal of striving for zero prevalence of persistent symptoms of TD in anyone treated for psychosis.

The Clinical and Economic Burden of Tardive Dyskinesia in Israel: Real-World Data Analysis

PURPOSE/BACKGROUND

Tardive dyskinesia (TD) is a hyperkinetic movement disorder caused by exposure to dopamine-receptor blockers. Data on TD burden in Israel are scarce. This analysis assesses the clinical and economic burden of TD in Israeli patients.

METHODS/PROCEDURES

This retrospective analysis used a national health plan database (Maccabi Healthcare Services), representing 25% of the Israeli population. The study included adults alive at index date with an International Classification of Diseases, Ninth Revision, Clinical Modification TD diagnosis before 2018 and more than or equal to 1-year enrollment before diagnosis. Tardive dyskinesia patients were matched to non-TD patients (1:3) by underlying psychiatric condition, birth year, and sex. Treatment patterns and 2018 annual health care resource utilization and costs were assessed.

FINDINGS/RESULTS

Of 454 TD patients alive between 2013 and 2018, 333 alive on January 1, 2018, were matched to 999 non-TD patients. At baseline, TD patients had lower socioeconomic status and higher proportion of chronic kidney disease and antipsychotic medication use; all analyses were adjusted accordingly. Tardive dyskinesia patients had significantly more visits to general physicians, neurologists, psychiatrists, physiotherapists, and emergency departments versus non-TD patients (all P < 0.05). Tardive dyskinesia patients also had significantly longer hospital stays than non-TD patients ( P = 0.003). Total healthcare and medication costs per patient were significantly higher in the TD versus non-TD population (US $11,079 vs US $7145, P = 0.018).

IMPLICATIONS/CONCLUSIONS

Israeli TD patients have higher clinical and economic burden than non-TD patients. Understanding real-world health care resource utilization and costs allows clinicians and decision makers to quantify TD burden and prioritize resources for TD patients' treatment.