No Postural Stability Differences between Asymptomatic and Symptomatic Neurological Orthostatic Hypotension in Parkinson’s disease – A Pilot Study (P1.051)

Objective: To evaluate the differences in postural stability during neurogenic orthostatic hypotension (NOH) in Parkinson’s disease (PD), specifically looking at the difference between symptomatic and asymptomatic patients. Background: It is well known that PD patients are at an increased risk for falling compared to healthy elderly adults. Although postural instability is a cardinal feature of PD, not all falls can be attributed to this symptom. A large portion of PD patients also develop orthostatic hypotension, which is defined as a drop of 20 mmHg or greater in systolic blood pressure. This study aims to determine the effect of NOH on postural stability in PD. Design/Methods: Twenty-one subjects with PD from Barrow Neurological Institute in Phoenix, Arizona underwent clinical tilt table testing for NOH. Before and after the tilt testing, subjects were asked to stand quietly on a force plate for one minute with their eyes open and then again with their eyes closed. Different postural stability measures were calculated from the center of pressure data during each of the trials. The force plate collected data at 100 Hz. Results: Of the 21 subjects tested, three did not have orthostatic hypotension and were removed from this analysis. The remaining 18 subjects were 73.3 ± 7.5 years old and had been diagnosed with PD for 5.6 ± 5.5 years. No significant differences were found in postural stability between PD patients who did and did not experience symptoms of NOH for both eyes open and eyes closed trials. Conclusions: PD patients’ postural stability is affected during NOH, regardless of whether or not if the patient experiences any symptoms of NOH. Disclosure: Dr. Smith has nothing to disclose. Dr. Frames has nothing to disclose. Dr. Olson has nothing to disclose. Dr. Lockhart has nothing to disclose. Dr. Lieberman has nothing to disclose.