Parasympathetic Dysfunction Prevails in GBA1‐Associated Parkinson's Disease

Background: The role played by sympathetic and parasympathetic autonomic branches in patients with Parkinson's disease carrying variants in the GBA1 gene (GBA-PD) is still elusive. Objectives: To characterize cardiovascular autonomic function in GBA-PD and I-PD patients with early and mid-stage disease. Methods: These assessments were performed: cardiovascular autonomic tests, analysis of heart rate and blood pressure variability, cardiac noradrenergic imaging. The frequency and severity of autonomic symptoms were comparatively assessed with the SCOPA-AUT questionnaire. Results: Compared to the I-PD cohort, GBA-PD patients displayed an increased burden of autonomic symptoms. Autonomic tests revealed worse parasympathetic scores in GBA-PD while sympathetic indexes and the degree of cardiac sympathetic binding were comparable in the two groups. Heart rate variability indexes also revealed lower vagal modulation in the GBA-PD group. Conclusions: The cardiovascular autonomic profile in GBA PD is characterized by a prominent cardiovagal dysfunction compared to I-PD.