OBJECTIVES: Despite being among the most common movement disorder in the US, little research has examined the indirect burden of essential tremor (ET). This study describes productivity impairment in patients with ET.

METHODS: The Work Productivity and Activity Impairment (WPAI) Questionnaire was analyzed for participating patients in the Adelphi ET Disease Specific Programme. Pearson correlations and regression models, adjusting for relevant covariates, were used to assess associations between productivity and activity impairment and tremor severity as measured by The Essential Tremor Rating Scale (TETRAS) Performance Subscale, Performance Item 4, and Activities of Daily Living Subscale (ADL).

RESULTS: Patients with ET who provided WPAI-based daily activity impairment information (n=420) were 64.4 years old (standard deviation [SD]=13.8) on average and 47% female. In the employed analytic sample [EAS; n=165], mean age was 55.0 years [SD=10.1], and 41% female. Most were employed full-time (n=133 vs part-time n=32). Mean work productivity impairment among employed patients (absenteeism and presenteeism) was 29.5% (SD=22.6%), representing approximately 12 hours of work-loss per 40-hour workweek. Over 90% of work-loss was due to presenteeism. Work productivity impairment increased with TETRAS ADL scores (TETRAS ADL 0-9: 22%, 10-19: 27%, 20-29: 37%, and ≥30: 55%). Similar increases in impairment were observed for the TETRAS Performance Subscale and Performance Item 4. Mean activity impairment was 29.0% in the EAS (35.3% in overall sample). Higher patient work productivity impairment (rs=0.32-0.44) and activity impairment (rs=0.37-0.43) were moderately associated with greater tremor severity; associations were moderate and statistically significant in regression modeling.

CONCLUSIONS: ET contributes to substantial productivity impairment, with important implications in the workplace for those who are employed. Overall, increased severity of tremor may further impact productivity impairment among patients with ET. Results suggest that new ET treatments that improve tremor may help mitigate the indirect burden on patients and society.