Category: Parkinson's Disease: Pathophysiology
Objective: We assessed whether orthostatic blood pressure (BP) and heart rate (HR) changes in an early motor PD cohort influence motor, and postural instability and gait related outcomes (axial motor outcomes) at five-year follow up. Additionally, we hypothesize that a more rapid change in orthostatic vital signs from baseline to 1-year is associated with poorer longitudinal outcomes on the same variables.
Background: Dysautonomia is a known complication of PD[1, 2]. In PD, cardiovascular dysautonomia[3] and orthostatic BP[4, 5] have shown to correlate with worse motor outcomes at 5 and 2 years follow up. We aimed to assess if orthostatic hypotension examined off medication would still correlate with motor outcomes, and specifically, axial motor outcomes, as disease progresses.
Method: Our analysis included PPMI subjects whose baseline and 1-year follow-up orthostatic vital signs, and 5-year follow-up MDS-UPDRS Parts II and III (OFF Meds) scores were available.
We created two random forest models. A full model with our variables of interest, and a control model excluding our variables of interest for comparison. The full model included orthostatic BP and HR changes, age, sex, and baseline MDS-UPDRS scores as variables, whereas the control model excluded vital sign changes. Our two general motor outcomes were total MDS-UPDRS II and III, and our two axial outcomes were the sum of MDS-UPDRS 2.11-2.13 and 3.9-3.13 scores. To determine whether our variables of interest impacted the outcomes, we compared the mean absolute errors between models.
Results: Of the subjects with available data, MDS-UPDRS II and OFF-Med III scores were available for 418 and 283 subjects, respectively. The difference in mean absolute errors between full and control models was not significant in predicting overall motor (p=0.98, p=0.81) and axial outcomes (p=0.66, p=0.83).
Conclusion: Unlike the studies referenced, we did not find that orthostatic vital sign changes influence longitudinal PD motor and axial outcomes in this early motor PD cohort. Additionally, a more rapid change in orthostatic vitals from baseline to 1-year was not associated with worse longitudinal outcomes. In our study, dysautonomia involving BP and HR changes in PD did not influence general motor and axial outcomes in early PD. As PD presents in different forms and degrees of severity it is possible that findings may be different in subsets of PD patients with worse phenotype.
References: 1. Merola A, Romagnolo A, Rosso M, Suri R, Berndt Z, Maule S, et al. Autonomic dysfunction in Parkinson’s disease: A prospective cohort study. Movement disorders : official journal of the Movement Disorder Society. 2018;33(3):391-7.
2. Palma JA, Kaufmann H. Epidemiology, Diagnosis, and Management of Neurogenic Orthostatic Hypotension. Mov Disord Clin Pract. 2017;4(3):298-308.
3. Longardner K, Merola A, Litvan I, De Stefano AM, Maule S, Vallelonga F, et al. Differential impact of individual autonomic domains on clinical outcomes in Parkinson’s disease. J Neurol. 2022;269(10):5510-20.
4. Kotagal V, Lineback C, Bohnen NI, Albin RL, Investigators C-PPSG. Orthostatic hypotension predicts motor decline in early Parkinson disease. Parkinsonism & related disorders. 2016;32:127-9.
5. You S, Kim HA, Lee H. Association of Postural Instability with Autonomic Dysfunction in Early Parkinson’s Disease. J Clin Med. 2020;9(11).
To cite this abstract in AMA style:
J. Li, J. Ruiz Tejeda, D. Tran, S. Nguyen, N. Phielipp. Orthostatic vital sign changes do not influence 5-year motor outcomes in PD [abstract]. Mov Disord. 2023; 38 (suppl 1). https://www.mdsabstracts.org/abstract/orthostatic-vital-sign-changes-do-not-influence-5-year-motor-outcomes-in-pd/. Accessed December 10, 2024.« Back to 2023 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/orthostatic-vital-sign-changes-do-not-influence-5-year-motor-outcomes-in-pd/