Autonomic features in Parkinson disease

Nonmotor symptoms such as autonomic and neuropsychiatric dysfunctions, are commonly seen in Parkinson disease (PD). Recent studies have shown that PD is accompanied by cardiac sympathetic denervation and constipation even in the early stage. Neuropathological studies confirmed changes in the cardiac sympathetic nerves and the gastrointestinal tract. These findings suggest that PD neuropathology may occur first in the peripheral autonomic pathways and extend to the central autonomic pathways, in agreement with the "Braak theory". This article will reviews the symptoms and pathophysiology of gastrointestinal dysfunction, urinary disturbance, sexual dysfunction, sweating dysfunction, pupillary autonomic dysfunction, and orthostatic and postprandial hypotension in PD patients, and discuss to organ selectiveness in autonomic dysfunction in PD.