Scientific knowledge of tardive dyskinesia (TD) over the past five decades will prove useful for researchers seeking relevant literature when authoring scientific articles, selecting pertinent journals, searching for research collaborators or mentors, as well as better understanding the historical significance of TD research and identify emerging trends. Physician’s Weekly interviewed Christoph U. Correll, MD, on this topic. Dr. Correll and colleagues recently published the study in Frontiers in Psychiatry.

Physician’s Weekly: What needs exist for your research?

Dr. Correll: Scientometric research studies provide an opportunity to summarize an area of research based on the wealth of published articles. In the case of TD, this systematic overview includes the evolution of research topics and turning points and identifies individuals with specific expertise who can serve as collaborators or mentors, and journals that are pertinent for articles in the area of TD.

Can you briefly explain what you and your colleagues set out to determine with this study and how it was conducted?

We aimed to synthesize an extensive body of research to understand the clinical characteristics, epidemiology, pathophysiology, and management of TD, and sought to identify trends and hotspots within knowledge domains.

What findings from your study are important to stress to our physician readers, particularly psychiatrists and neurologists?

To date, the exact mechanism underlying the emergence of TD remains unknown, but clinically relevant risk factors and, more recently, effective and evidence-based treatments, are better delineated. Trends in the study of TD in the past 54 years include:

  • 1960–1970s: the clinical and pharmacological characterization of TD;
  • 1980s: epidemiology, clinical TD assessment, cognitive dysfunction, and animal models predominated;
  • 1990s: research into pathophysiological studies, especially oxidative stress, and clinical trials on atypical antipsychotics, with a specific focus on clozapine and bipolar disorder; and
  • 1990–2000s: the emergence of pharmacogenetics as an important theme.
  • More recent knowledge clusters include serotonergic receptors, dopamine-supersensitivity psychosis, primary motor abnormalities of schizophrenia, epidemiology/meta-analyses, and advances in TD treatment, particularly vesicular monoamine transporter-2 inhibitors (VMAT2) since FDA approval in 2017 of deutetrabenazine and valbenazine, the first two treatments with sufficient randomized controlled trial evidence for the amelioration of TD.

How would you like to see physicians incorporate your findings into their practices?

Physicians should aim to increase awareness that TD remains a reality for a relevant number of patients treated with dopamine receptor blocking agents. Moreover, prevention of TD is key, through use of dopamine receptor blockers only if indicated, only for as long as needed, and at doses below the threshold of the development of parkinsonism or akathisia. Additionally, adequate education about the potential risk for TD is needed as well as regular monitoring to identify the development of TD as early as possible. Finally, timely treatment for TD, namely with approved vesicular monoamine transporter inhibitors, is critical.

What needs still exist in this area?

Future research is needed into the incidence of TD in non-psychotic disorders where atypical antipsychotics are used more frequently, but also often at lower doses than in psychotic disorders for which currently most data exist. Additional areas of research should include the personal, interpersonal, and functional impact of TD and predictors of response and remission of TD when VMAT2 inhibitors are used to treat TD.

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