Forehead sympathetic skin responses in determining autonomic involvement in Parkinson's disease.

Objective: The purpose of this study was to evaluate forehead sympathetic skin response (SSR) and demonstrate any differences with extremity SSR in determining autonomic nervous system (ANS) involvement in patients with Parkinson's disease (PD).

Methods: Twenty early stage, 20 advanced stage idiopathic PD patients and 20 healthy controls participated in this study. SSR of forehead, hands and feet, heart rate variability (HRV), orthostatic intolerance, QT intervals and dysautonomic symptoms were evaluated.