Ann Neurol. 2015 Feb 23. doi: 10.1002/ana.24393. [Epub ahead of print]
Alonso A, Huang X, Mosley TH, Heiss G, Chen H.
Objectives: Autonomic dysfunction frequently occurs in the context of Parkinson's disease (PD) and may precede onset of motor symptoms. Limited data exist on the prospective association of heart rate variability (HRV), a marker of autonomic function, with PD risk. Methods: We included 12,162 participants of the Atherosclerosis Risk in Communities (ARIC) study, a community-based cohort, without a diagnosis of PD at baseline (1987-89) and with available HRV data (mean age 54, 57% women). A 2-minute electrocardiogram was used to measure HRV. Incident PD was identified through 2008 from multiple sources, and adjudicated. Multivariable Cox models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of PD by quartiles of HRV measurements. Results: During a mean follow-up of 18 years, we identified 78 incident PD cases. Lower values of the root mean square of successive differences in normal-to-normal R-R intervals (rMSSD) and standard deviation of normal-to-normal R-R intervals (SDNN), markers of parasympathetic activity and total variability respectively, were associated with higher PD risk during follow-up. In multivariable models, the HR (95%CI) of PD in the bottom quartiles of rMSSD and SDNN compared to the top quartiles were 2.1 (1.0-4.3) and 2.9 (1.4-6.1), respectively. Other measures of cardiac autonomic function, including mean RR interval and frequency-domain measurements, were not associated with PD risk. Interpretation: In this prospective cohort, decreased HRV was associated with an increased risk of PD. Assessment of cardiac autonomic function may help identify individuals at risk for PD.