Heart Rate Variability in leucine-rich repeat kinase 2-Associated Parkinson's Disease

Background: Heart rate variability is reduced in idiopathic PD, indicating cardiac autonomic dysfunction likely resulting from peripheral autonomic synucleinopathy. Little is known about heart rate variability in leucine-rich repeat kinase 2-associated PD. Objectives: This study investigated heart rate variability in LRRK2-associated PD. Methods: Resting electrocardiograms were obtained from 20 individuals with LRRK2-associated PD, 37 nonmanifesting carriers, 48 related noncarriers, 26 idiopathic PD patients, and 32 controls. Linear regression modelling compared time and frequency domain values, adjusting for age, sex, heart rate, and disease duration. Results: Low-frequency power and the ratio of low-high frequency power were reduced in idiopathic PD versus controls (P <. 008, P <. 029 respectively). In contrast, individuals with LRRK2-associated PD were not statistically different from controls in any parameter measured. Furthermore, all parameters trended toward being higher in LRRK2-associated PD when compared with idiopathic PD. Conclusions: Heart rate variability may remain intact in LRRK2-associated PD, adding to a growing literature supporting clinical-pathologic differences between LRRK2-associated and idiopathic PD. (C) 2017 International Parkinson and Movement Disorder Society