Is reduced myocardial sympathetic innervation associated with clinical symptoms of autonomic impairment in idiopathic Parkinson's disease?

Patients with idiopathic Parkinson's disease (IPD) have a reduced myocardial MIBG uptake in MIBG scintigraphy, indicating myocardial sympathetic denervation. We were interested whether this myocardial sympathetic denervation coincides with clinical symptoms of autonomic impairment in IPD patients. We performed MIBG scintigraphy, the SCOPA-AUT scale, a standardized medical history (developed in our clinic) and autonomic nervous system testing in 47 IPD patients (21 female, 26 male patients). We correlated myocardial MIBG uptake with the results of the SCOPA-AUT scale, the standardized medical history and the autonomic nervous system testing through the use of Spearman's correlation. Myocardial MIBG uptake correlated significantly (p < 0.05) with several items of the SCOPA-AUT scale (in female patients: perspiration during the night, in male patients: sum score, saliva dribbling of the mouth, difficulty swallowing, fainting, constipation), of the standardized medical history (in male patients: swollen ankles) and of the autonomic nervous system testing (all patients: sum score, Ewing orthostasis test). Remarkably, we found more significant correlations in male than in female patients. Reduced myocardial sympathetic innervation-as revealed by MIBG scintigraphy-is associated with clinical symptoms of autonomic impairment. This association is more pronounced in male than in female patients. The cause for this gender-specific phenomenon is unclear.