We sought to determine if continuous measurement of blood pressure using a beat-to-beat non-invasive blood pressure monitor (cNIBP) coupled with wearable motion sensors (WMS) may detect postural instability events and correlate with episodes of neurogenic orthostatic hypotension (OH) in patients with Parkinson disease (PD), helping in the prediction of fall risk.

OH may affect up to 40% of patients with PD, frequently resulting in falls and fractures. Only half of PD-OH patients, however, report postural lightheadedness. Others may be asymptomatic or complain of weakness, confusion, or difficulty concentrating, which may not be considered related to OH and are not adequately captured by OH-screening questionnaires.

Sit-to-stand events associated with postural instability occurred with periods of lower diastolic BP than sit-to-stand events without instability. In patients who had instability during both iTUG tests and ADLs, there was a reduction in BP in only 52% of instability events. In those subjects less than half of reductions in systolic BP >20 mmHg were followed by instability events.