Clinical utility of SUDOSCAN in predicting autonomic neuropathy in patients with Parkinson's disease.

INTRODUCTION: Autonomic neuropathy is common in Parkinson's disease (PD). We evaluated whether SUDOSCAN, a novel electrophysiological device that provides a simple and quantitative assessment of sudomotor function, was able to detect PD-related autonomic neuropathy. We also used the device to examine potential risk factors for PD-related autonomic neuropathy.

METHODS: Forty-three hospitalized patients in the later stages of PD underwent assessments including a clinical history, the Unified Parkinson's Disease Rating Scale (UPDRS), the Scale for Outcomes in Parkinson's disease for Autonomic Symptoms (SCOPA-AUT), and measurement of homocysteine (HCY) and vitamin B12 levels. Sudomotor function was assessed by measuring electrochemical skin conductance (ESC) using SUDOSCAN. Forty-two healthy participants served as controls.

RESULTS: ESC of the limbs, and especially the hands, was significantly lower in PD patients than in controls and was significantly correlated with SCOPA-AUT results. ESC was strongly negatively correlated with PD duration. The results also indicated that levodopa exposure and a higher HCY level may be risk factors for PD-related autonomic neuropathy.

CONCLUSIONS: SUDOSCAN was able to effectively identify autonomic neuropathy in PD patients. ESC was decreased in PD patients and was correlated with PD-related autonomic symptoms. These findings suggest that SUDOSCAN could be a promising new method for assessing PD-related autonomic neuropathy.