Relationships between clinical characteristics and nocturnal cardiac autonomic activity in Parkinson's disease

BackgroundThe aim of the present study was to explore the association between Parkinson's disease (PD) clinical characteristics and cardiac autonomic control across sleep stages.MethodsFrequency-domain heart rate variability (HRV) measures were estimated in 18 PD patients undergoing a night of polysomnography.ResultsSignificant relationships were found between PD severity and nocturnal HRV indices. The associations were restricted to rapid eye movement (R) sleep.ConclusionsThe progressive nocturnal cardiac autonomic impairment occurring with more severe PD can be subclinical emerging only during conditions requiring active modulation of physiological functions such as R-sleep.