Robin Williams' wife released a statement today that revealed that the well-loved comedian was struggling with the early stages of Parkinson's disease. But what exactly is Parkinson’s and how does it affect the body?

What is Parkinson's Disease? 

Parkinson's disease is progressive disorder of the nervous system that affects movement. The disease develops gradually over time, often starting with a tremor in just one had. While a tremor is the most common sign of Parkinson's, the disorder also commonly causes stiffness and slowing of movement.

During the early stages of Parkinson's, your face may show little or no expression, and your arms may not swing when you walk. Your speech may become soft or slurred. The symptoms of the disease worsen as the conditions progresses over time.

There is no cure for Parkinson’s, but some medications can improve the symptoms. 

What are the Signs and Symptoms? 

Tremor: A tremor, or shaking, usually begins in one limb, oftentimes the hands or fingers. People with Parkinson's sometimes suffer from a "pill-rolling" tremor in which the thumb and forefinger rub back and forth. 

Slow movement: Over time, Parkinson's may reduce the ability to move or slow movement, which can make simple tasks difficult and time-consuming. Steps can become shorter when walking or feet may drag when trying to walk, and it may be hard to stand after sitting in a chair. 

Rigid muscles: Muscle stiffness can occur in any part of the body. Stiff muscles can limit range of motion and cause pain. 

Impaired posture and balance: Posture may become stooped or balance problems can result as a Parkinson's disease. 

Loss of automatic movements: Parkinson's can cause a decreased ability to perform unconscious movements including blinking, smiling and swinging of arms when walking. Gestures while talking may be limited. 

Speech changes: Speech problems can be a result of Parkinson's Disease. It can cause soft, quick speech or slurring and hesitation before talking. Speech can become more monotone, missing the usual inflections. 

Writing changes: Writing may appear small and become difficult. 

What causes Parkinson's Disease? 

Parkinson's disease causes certain nerve cells in the brain to break down and die. Many of the symptoms are due to the loss of neurons that produce the brain chemical dopamine. When dopamine levels decrease, it can lead to signs of Parkinson's disease. 

Several factors appear to play a role in causing Parkinson's Disease.

Researchers have identified a specific genetic mutation that can cause Parkinson's disease, but this is uncommon except in rare cases with many family members are afflicted with the disease. 

Exposure to certain toxins or environmental factors can increase the risk of developing Parkinson's disease later in life. 

Researchers are still working to determine the cause of the disease. 

What are the risk factors?

Some risk factors include age, heredity, gender and exposure to toxins. 

Young adults rarely experience Parkinson's disease. It usually begins in middle or late life, and the risk continues to increase with age. People usually develop the disease at age 60 or older. 

Having a close relative with Parkinson's disease increases the chance that a person will develop the disease. However, the risk is small unless you have many relatives with the disease. 

Men are more likely to develop Parkinson's disease than women. 

Ongoing exposure to certain herbicides and pesticides may put some at a slightly increased risk of Parkinson's.

Source: The Mayo Clinic