Category: Tremor
Objective: We aimed to characterize essential tremor and dystonic tremor using 3D accelerometry analysis.
Background: Diagnosing essential tremor (ET) and dystonic tremor (DT) is often challenging. Although correct diagnosis is vital for appropriate medical and surgical treatment, biomarkers for these tremor disorders have not been established.
Method: We analyzed postural and kinetic tremor using 3D accelerometers in ET (15 patients) and DT (19 patients), who were clinically diagnosed based on the MDS tremor classification 2018. Accelerometry data were analyzed using an in-house application to calculate peak frequency, half-width power (HWP), frequency width half magnitude (FWHM), and tremor stability index (TSI). asymmetry in the above-mentioned values were also calculated. The results were compared between the ET and DT groups using Mann-Whitney U tests. The statistical significance was set to a threshold of p < 0.05.
Results: The peak frequency of postural tremor and kinetic tremor was significantly greater in the ET group compared with the DT group: 6.7 ± 1.3 Hz in the ET group and 5.3 ± 1.6 Hz in the DT group for postural tremor (p = 0.005); 7.0 ± 1.1 Hz in the ET group and 5.9 ± 1.5 Hz in the DT group (p = 0.022) for simple kinetic tremor; 6.3 ± 1.1 Hz in the ET group and 5.1 ± 1.0 Hz in the DT group for kinetic tremor while writing (p = 0.002). Additionally, asymmetry in HWP of postural tremor and kinetic tremor was significantly greater in the DT group: 1.8 ± 0.7 in the ET group and 5.2 ± 5.9 in the DT group for postural tremor (p = 0.027); 2.0 ± 1.1 in the ET group and 4.1 ± 2.8 in the DT group for kinetic tremor while writing (p = 0.041). FWHM and TSI, which reflect variability of tremor frequency, were not significantly different between the groups.
Conclusion: Our findings imply that 3D accelerometry analysis holds the potential to differentiate ET and DT. While further validation through larger cohort studies is imperative, it is anticipated that this technique will serve as a valuable biomarker for objective diagnosis and severity assessment.
To cite this abstract in AMA style:
T. Tsuboi, K. Sawada, S. Hoshino, M. Higuchi, M. Mutho, Y. Ito, D. Nakatsubo, T. Ishizaki, T. Tanei, S. Maesawa, M. Sato, D. Tamakoshi, T. Uematsu, K. Hiraga, Y. Satake, M. Suzuki, R. Saito, M. Katsuno. 3D-accelerometry characteristics of essential tremor and dystonic tremor [abstract]. Mov Disord. 2023; 38 (suppl 1). https://www.mdsabstracts.org/abstract/3d-accelerometry-characteristics-of-essential-tremor-and-dystonic-tremor/. Accessed June 15, 2025.« Back to 2023 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/3d-accelerometry-characteristics-of-essential-tremor-and-dystonic-tremor/