Anatomical Distribution of Involuntary Movements and Clinician-Reported Impact of Tardive Dyskinesia: A Real-World Analysis of the IMPACT-TD Registry

Abstract: Background: To examine the relationship between the multidimensional impact of tardive dyskinesia (TD) on daily functioning and the anatomical distribution and severity of TD-associated movements.

Methods: Included IMPACT-TD Registry participants, aged ≥18 years, had a score of ≥2 on ≥1 item of the Abnormal Involuntary Movement Scale (AIMS) and probable TD with no active vesicular monoamine transporter 2 inhibitor treatment at enrollment. Clinicians rated TD impact in 4 life domains (social, psychological/psychiatric, physical, and vocational/educational/recreational) using the IMPACT-TD ClinRO scale (4-point Likert scale, highest domain score=global score). AIMS component scores (muscles of facial expression, jaw, lips/perioral area, tongue, upper extremities, lower extremities, and trunk) and their relationship with moderate/severe ClinRO domain scores were evaluated.

Results: Across all ClinRO domains, individuals who experienced moderate/severe impact of TD had median AIMS component scores of 2 (muscles of facial expression, upper extremities), 1 (tongue, lower extremities), and 0 (trunk). AIMS component scores in the lips/perioral area and in the jaw varied by ClinRO domain (social, physical: median=2; psychological/psychiatric, vocational/educational/recreational: median=1). Among individuals with AIMS 1/2 in any body region, 71—81% experienced moderate/severe global TD impact, with highest impact seen in the psychological domain. Among individuals with AIMS 3/4 in either muscles of facial expression, lower extremities, or trunk, ≥80% experienced moderate/severe impact of TD in each ClinRO domain.

Conclusions: Even with AIMS component scores 1/2, individuals experienced moderate/severe multidimensional impact of TD.