From the Parkinson's Foundation:
Parkinson's disease (PD) is a neurodegenerative disorder that affects predominately dopamine-producing (“dopaminergic”) neurons in a specific area of the brain called substantia nigra.
Symptoms generally develop slowly over years. The progression of symptoms is often a bit different from one person to another due to the diversity of the disease. People with PD may experience:
- Tremor, mainly at rest and described as pill rolling tremor in hands. Other forms of tremor are possible
- Bradykinesia
- Limb rigidity
- Gait and balance problems
The cause remains largely unknown. Although there is no cure, treatment options vary and include medications and surgery. While Parkinson’s itself is not fatal, disease complications can be serious. The Centers for Disease Control and Prevention (CDC) rated complications from PD as the 14th cause of death in the United States.