Similar association between objective and subjective symptoms in functional and organic tremorKramer, G., Dominguez-Vega, Z. T., Laarhoven, H. S. A., Brandsma, R., Smit, M., van der Stouwe, A. M. M., Elting, J. W. J., Maurits, N. M., Rosmalen, J. G. M. & Tijssen, M. A. J., Jul-2019, In : Parkinsonism & Related Disorders. 64, p. 2-7 6 p.
Research output: Contribution to journal › Article › Academic › peer-review
Background: A previous study reported a dramatic mismatch in objectively detected and self-reported tremor duration in patients with functional tremor. As these findings have an important and widespread impact in both clinical care and research, we conducted a validation study with a longer study duration and a larger sample of patients.
Methods: Fourteen patients with functional tremor and 19 with organic tremor completed a 30 day study period. Objective tremor duration was recorded using a wrist-worn accelerometer. Simultaneously, participants completed a web-based diary five times a day, each time rating their symptom burden since the previous diary entry.
Results: Patients with functional tremor had shorter objective tremor duration compared to patients with organic tremor (21.6% vs 30.7%, P = 0.034). A post-hoc analysis revealed the difference in objective duration was mainly due to patients with essential tremor (37.2%). Subjective symptom burden was not significantly different between functional and organic tremors (38.7 vs 28.7 on a 0-100 VAS scale, P = 0.138). Finally, a mixed model analysis did not reveal significant differences in the association between subjective and objective tremor symptoms (P = 0.168).
Conclusions: patients with functional tremor do have an objectively detectable, persistent tremor during daily life activities. Furthermore, they have a similar symptom burden and a similar association between subjective and objective tremor symptoms as patients with organic tremor.
|Number of pages||6|
|Journal||Parkinsonism & Related Disorders|
|Publication status||Published - Jul-2019|
- Functional movement disorder, Tremor, Actigraphy, Self-report, Ambulatory assessment, PSYCHOGENIC MOVEMENT-DISORDERS, RATING-SCALE, PARKINSONS, TIME