Waveform analysis of tremor may help to differentiate Parkinson's disease from drug-induced parkinsonism

Abstract

In this study, we analyzed the waveform characteristics of resting tremor by accelerometer recordings in patients with drug-induced parkinsonism (DIP) and Parkinson's disease (PD). We prospectively recruited 12 patients with tremulous PD and 12 patients with DIP presenting with resting tremor. Tremor was recorded from the more affected side and was recorded twice for a 60 s period in each patient. Peak frequency, amplitude and all harmonic peaks were obtained, and the asymmetry of the decay of the autocorrelation function, third momentum and time-reversal invariance were also computed using a mathematical algorithm. Among the parameters used in the waveform analysis, the harmonic ratio, time-reversal invariance and asymmetric decay of the autocorrelation function were different between PD and DIP at a statistically significant level (all p < 0.01). The total harmonic peak power and third momentum in the time series were not significantly different. The clinical characteristics of DIP patients may be similar to those of PD patients in some cases, which makes the clinical differentiation between DIP and PD challenging. Our study shows that the identification of parameters reflecting waveform asymmetry might be helpful in differentiating between DIP and PD.

The Characteristics of Tremor Motion Help Identify Parkinson's Disease and Multiple System Atrophy

“…Majchrzak et al demonstrated that, compared to healthy controls, the harmonic index of tremor motions (the distance of the spectrum to the single narrow peak, which was normalized to the highest peak) was significantly higher in patients with Parkinsonian tremor, essential tremor, and cerebellar tremor ( 24 ). Jang et al reported that the harmonic ratio (the value of the total harmonic peak power divided by the number of harmonic peaks) was remarkably lower in PD patients than in drug-induced Parkinsonism patients ( 25 ). In another study, Muthuraman et al .…”

Wearable Sensor Based Stooped Posture Estimation in Simulated Parkinson’s Disease Gaits

“…Although walking and tremor motions are identified as major influencing artifacts, they can be mainly eliminated by using averaging algorithms, owing to their symmetric waveforms. A deep analysis made by Jang et al [25] reported that tremors in PD are symmetric. In the same vein, human gait has been illustrated to have a sinusoidal form, even at high walking speeds [26].…”

Quantifying Motor Impairment in Movement Disorders

“…This provides the clinician at zero cost (provided they have a telephone) with an instant alternative to electromyographic tremor studies. Spectral analysis of accelerometer (Hossen et al, 2013 ) and gyroscopic (Bhidayasiri et al, 2014 ) measurements can discriminate between PD tremor and Essential Tremor (ET) or between idiopathic and drug-induced parkinsonism (Jang et al, 2013 ). Accelerometer studies have even attempted to subdivide these conditions, for example separating patients with essential tremor into those that are position-dependent vs. position-independent (Golan et al, 2004 ), or differentiating tremor frequency characteristics of PD patients under resting vs. stressed states (Lee et al, 2016 ).…”