This prospective study was carried out at the Pacific Parkinson’s Research Center, University of British Columbia. Following approval by the Ethics Board, all subjects had provided written, informed consent.
We recruited 25 patients diagnosed with PD by certified movement disorder specialists according to the United Kingdom Parkinson’s Disease Society Brain Bank Criteria. Exclusion criteria included (i) atypical Parkinsonism, (ii) depressive mood identified by Beck Depression Inventory-II (BDI-II)>14 or concurrent treatment with antidepressants, (iii) cognitive impairment measured by Montreal Cognitive Assessment ≤ 22, (iv) history of epilepsy, polyneuropathy, spinal cord diseases, thyroid dysfunction, or severe dermatological conditions, and (v) history of deep brain stimulation, implantation of any medical devices, or anticholinergic medication use.
Demographic features including age, sex, duration of disease after initial diagnosis, and total daily L-dopa dose were obtained. Overall severity of Parkinsonism was assessed by Unified Parkinson’s Disease Rating Scale (UPDRS) part III in all participants. The “wearing off questionnaire-19 (WOQ-19)”, a clinical scale that measures the degree of fluctuations in both motor and non-motor symptoms, was assessed in all patients. A compact view of subjects’ responses to the questionnaire is plotted in
Figure S1. Participants were considered to have WO if they experienced at least two or more symptoms in WOQ 19 that improved with L-dopa intake [28 (
link),29 (
link)]. The Scales for Outcomes in Parkinson’s disease-AUTonomic dysfunction (SCOPA-AUT) was used to assess any pre-existent autonomic system function [30 (
link)].
Table 1 lists the main demographic features of each subject.
A wearable wristband, E4 wristband
® (Empatica Inc., Milan, Italy), was used to obtain EDA, HR, BVP, and TEMP information. It carries out EDA measurements with two dry silver-plated electrodes that are attached to the inner surface of the watch with a sampling rate of 4 Hz and a range of skin conductance (SC) from 0.01 μS to 100 μS. BVP is measured by photoplethysmography (PPG) (and from that, HR can be inferred) [31 (
link)]. The PPG sensor evaluates the volume of the passing blood along tissues using a photo-detector that computes the reflection coefficient of light (generated by PPG’s light source) from the skin [32 (
link)]. The sampling rate of BVP is 64 Hz. The E4 is also equipped with an infrared thermopile sensor that reads peripheral skin temperature (with a frequency sampling rate of 4 Hz) [33 ].
An activity log was kept by the patients that contained their self-reports of time past from the latest dose, sleep, and ON/OFF reports performed every 30 minutes while wearing the device for a period of 24 hours. A report of “OFF” from any patient meant that he/she felt the urge for the medication, and “ON” had the opposite interpretation. They were instructed to carry out normal daily activities while being careful not to dislodge the electrodes and avoiding exposing the device to water. The E4 data were downloaded from the device later offline. For this proof-of-principle study, we restricted ourselves to the 12 subjects who documented “OFF” states in their diary. The other 13 subjects declared they had WO episodes but had failed to record this in their diary.
Arasteh E., Mirian M.S., Verchere W.D., Surathi P., Nene D., Allahdadian S., Doo M., Park K.W., Ray S, & McKeown M.J. (2023). An Individualized Multi-Modal Approach for Detection of Medication “Off” Episodes in Parkinson’s Disease via Wearable Sensors. Journal of Personalized Medicine, 13(2), 265.