Evaluating Orthostatic Responses with Wearable Chest-Based Photoplethysmography in Patients with Parkinson's Disease

• Main Authors: Berkebile, John A., Inan, Omer T., Beach, Paul A.
• Format: Conference Proceeding
• Language: English
• Subjects: Baroreflex; Biomedical monitoring; cardiac sensing; Electrocardiography; orthostatic hypotension; Parkinson's disease; Pathology; Photoplethysmography; Regulation; wearable sensing
• ISSN: 2168-9229
• DOI: 10.1109/SENSORS56945.2023.10324998

Orthostatic hypotension (OH) is a hallmark manifestation of cardiovascular autonomic dysfunction in Parkinson's disease (PD). Following an orthostatic stressor, OH in PD is characterized by impaired baroreflex and vasomotor function, resulting in a pathological fall in blood pressure (BP). The morbidity associated with cardiovascular autonomic dysfunction, in conjunction with the current limitations of methods for assessing OH, presents a challenging clinical and technological problem. Wearable cardiovascular sensing holds promise for improving detection and management of OH. In this study, participants with PD ( \mathrm{n}=6, 3 with OH) underwent an orthostatic challenge wearing a chest patch capturing electrocardiogram (ECG) and photoplethysmogram (PPG) signals alongside reference beat-to-beat BP. From supine to standing, PPG amplitude decreased significantly more ( \mathrm{p} < 0.05 ) in the PD+OH group compared to the PD group. Further, the change in PPG amplitude was significantly correlated ( \mathrm{r}=0.83,\ \mathrm{p} < 0.05 ) to the change in pulse pressure (PP) during the orthostatic challenge. These findings suggest that sternal PPG amplitude is a potential discriminative marker of OH and may enable noninvasive detection of OH episodes, allowing for earlier diagnoses and more optimal management of cardiovascular autonomic health.