Tardive dyskinesia (TD) is a persistent and potentially disabling movement disorder associated with prolonged antipsychotic use. RE KINECT, a real-world screening study of antipsychotic-treated outpatients, included patients with movements that were clinician-confirmed as possible TD (Cohort 2) and patients with no involuntary movements (Cohort 1). Baseline data from the patient rated EuroQoL 5-Dimension 5-Level questionnaire (EQ-5D-5L) and Sheehan Disability Scale (SDS) were analyzed to evaluate health related quality of life (Cohort 2 vs. Cohort 1) and the effects of possible TD on quality of life (Cohort 2).

Assessments included EQ-5D-5L utility score (0=equivalent to death to 1=perfect health); SDS total score (0=no impact to 30=highest impact); patient- and clinician-rated severity of possible TD in 4 body regions (0=none, 1=some, and 2=a lot; summary score, 0 to 8); and patient-rated impact of possible TD in 7 daily activities (0=none, 1=some, and 2=a lot; summary score, 0 to 14). Populations included Cohort 1 (N=450); full Cohort 2 (N=204); and limited Cohort 2 (N=111, patients who self-reported “some” or “a lot” of TD severity in ≥1 body region). Mean differences between Cohort 2 and Cohort 1 in EQ-5D-5L utility and SDS total scores were analyzed using a generalized linear regression model that was adjusted for potentially confounding factors (e.g., age, sex, psychiatric diagnosis). Associations between TD summary scores (severity, impact) and quality of life (EQ-5D-5L utility, SDS total) were analyzed using a regression model.

The mean score difference between full Cohort 2 (N=204) and Cohort 1 (N=450) was significant for EQ-5D-5L utility (-0.037; P<0.05 [adjusted analysis]) but not SDS total (0.267; P>0.05). However, when limited to Cohort 2 patients who self-reported “a lot” of TD severity (n=53) or impact (n=33), both EQ 5D 5L utility and SDS total scores were significantly worse than in Cohort 1 (P<0.05). Regression coefficients indicated significant associations between patient-rated impact and EQ 5D-5L utility in the full Cohort 2 (-0.021, P<0.001) and limited Cohort 2 (-0.024, P<0.001). A significant association was also found with patient rated severity in limited Cohort 2 (P<0.05), but not with clinician-rated severity. Similar results were found for SDS total score.

RE-KINECT patients were consistent in evaluating the severity and impact of TD, whether based on subjective assessments or standardized patient-reported instruments (EQ-5D-5L, SDS). Clinician-rated severity of TD may not always correlate with patient perceptions of the significance of TD. Patient self-assessments (focused on symptom impact) can be clinically relevant; incorporating such measures into everyday practice may provide a more comprehensive approach to TD assessment and management.

Supported by Neurocrine Biosciences, Inc.