Treatment of Nonmotor Symptoms Associated with Parkinson Disease.

Parkinson disease (PD) is well recognized by its motor features of bradykinesia, tremor, rigidity, and gait and balance difficulties. However, PD is also characterized by a myriad of nonmotor symptoms, which may occur even before motor symptoms, early in the course of disease, and throughout the advancing disease. These nonmotor symptoms span multiple different systems, invoke multiple different neurotransmitters, and require multiple strategies for treatment including pharmacologic and nonpharmacologic interventions and, often, multiple different disciplines. This article discusses symptoms, assessments, and therapeutics for the nonmotor symptoms of PD including those affecting mood, cognition, behavior, sleep, autonomic function, and sensory systems.