What is Parkinson's disease?

Parkinson’s disease affects both men and women. The average age of onset of Parkinson’s disease is 61, but it may begin as early as age 40 or even before. It is the second most common neurodegenerative disorder and the most common movement disorder. It is characterized by progressive loss of muscle control, which leads to trembling of the limbs and head while at rest, stiffness, slowness, and impaired balance. As symptoms worsen, it may become difficult to walk, talk, and complete simple tasks.

Other symptoms of Parkinson’s disease may include depression, anxiety, dementia (impaired thinking), difficulty in swallowing and chewing, speech changes, urinary problems or constipation, very oily or very dry skin, excessive sweating, and sleep problems.  Not all these symptoms occur in everyone with Parkinson’s disease.
The progression of Parkinson's disease and the degree of impairment vary from individual to individual. Many people with Parkinson's disease live long productive lives, whereas others become disabled much more quickly.

What causes Parkinson's disease:

The neurons that degenerate in Parkinson’s disease are located in several areas of the brain, but most significant is the loss of dopamine-producing neurons in the substantia nigra. The dopamine produced by these neurons is crucial for another brain region, called the striatum (see diagram). Under the influence of dopamine, signals from the striatum regulate all forms of voluntary movement. The loss of dopamine in Parkinson’s disease accounts for most of the movement-related symptoms of the disease. Dopamine neurons die over the course of many years. Parkinson’s disease symptoms begin when the loss of dopamine reaches a critical point, typically when 50 to 80 percent of dopamine neurons have died.


ّImportant Links

A Window Into Parkinson’s Disease