Parkinson Disease Dementia

• Parkinson Disease Dementia Overview
• Parkinson Disease Dementia Causes
• Parkinson Disease Dementia Symptoms
• When to Seek Medical Care
• Exams and Tests
• Parkinson Disease Dementia Treatment
• Self-Care at Home
• Medical Treatment
• Medications
• Surgery
• Next Steps
• Follow-up
• Prevention
• Outlook
• Support Groups and Counseling
• For More Information
• Web Links
• Synonyms and Keywords
• Authors and Editors

Parkinson Disease Dementia Overview

Parkinson disease (PD) is a degenerative disorder of the brain. It mainly affects movements of the body.

• The most common symptoms are tremor (shaking or trembling) of the hands, arms, jaw, and face; rigidity (stiffness) of the trunk and limbs; slowness of movement; and loss of balance and coordination.
  
  
• Other symptoms include shuffling, speaking difficulties, (or speaking very softly), facial masking (expressionless, mask-like face), swallowing problems, and stooped posture.
  
  
• The symptoms worsen gradually.

Depression, anxiety, personality and behavior changes, sleep disturbances, and sexual problems are commonly associated with PD. In many cases, PD does not affect a person’s ability to think, reason, learn, or remember (cognitive processes).

• In some patients with PD, however, one or more cognitive processes are impaired.
  
  
• If this impairment is severe enough to interfere with the person’s ability to carry out everyday activities, it is called dementia.

About 500,000 people in the United States have PD, and about 50,000 new cases are diagnosed each year. The number of those who have cognitive symptoms is difficult to pinpoint.

• The main problem is that researchers use various definitions of cognitive impairment and dementia.
  
  
• Another problem is that PD often overlaps with other degenerative brain disorders that can cause dementia, such as Alzheimer disease and vascular disease.
  
  
• Realistic estimates suggest that at least 50% of people with PD have some mild cognitive impairment. As many as 20-40% may have more severe symptoms or dementia.

Most patients have the first symptoms of PD after the age of 60 years, but PD also affects younger people. Early-onset PD strikes people around the age of 40 years, or even earlier.

• Regardless of age at onset of the disease, dementia symptoms tend to appear later in the course of the disease.
  
  
• Dementia is relatively rare in people with onset of PD before age 50 years, even when the disease is of long duration.
  
  
• Dementia is more common in people with an older age at onset of PD.