Recognition and treatment of neuropsychiatric disturbances in Parkinson's disease.

The non-motor symptoms of Parkinson's disease (PD) have been attracting increasing attention due to their ubiquitous nature and their often devastating effects on the quality of life. Behavioral problems in PD include dementia, depression, apathy, fatigue, anxiety, psychosis, akathisia, personality change, sleep disorders and impulse control disorders. Some of these are intrinsic to the neuropathology while others occur as an interplay between pathology, psychology and pharmacology. While few data exist for guiding therapy, enough is known to guide therapy in a rational manner.