Parkinson's disease

Parkinson’s disease is a degressive, degenerative neurological disease. It is a movement disorder, meaning that as the disease progresses, body movements such as walking and talking are affected.

How many people does Parkinson’s disease affect?

Parkinson’s disease affects 1 in every 500 people; approximately four million people worldwide.

Who is affected by Parkinson’s disease?

Although it affects both men and women statistically, men have a slightly higher chance of developing the disease. The risk of developing Parkinson’s disease also increases with age, with the average age of onset being 65 years old. Five to ten per cent of people who develop it are under 40 years old. When symptoms appear in people aged 21-40, this is known as young-onset Parkinson’s disease and in under 18 year olds, juvenile Parkinson’s disease although this is extremely rare.

No one knows exactly why people get Parkinson’s disease, but viral infection or environmental toxins may play a part. People with a parent, sibling or child with Parkinson’s disease, are twice as likely to get it as other people.

What causes Parkinson’s disease?

Parkinson’s disease develops with the loss of nerve cells in the brain which produce a chemical called dopamine. Dopamine is a chemical messenger (neurotransmitter) that transmits impulses between nerve cells in the brain to control body movements. Without enough dopamine, nerves in the brain which control muscle action do not work properly. When the loss of nerve cells reaches 80%, Parkinson’s disease symptoms begin to appear. The disease worsens over time as dopamine levels gradually fall.

The reason for the nerve damage is unknown, although two areas currently being researched as possible causes are genetics and environmental factors.

What are the symptoms of Parkinson’s disease?

The symptoms of Parkinson’s disease develop gradually, as levels of dopamine fall.To begin with, symptoms usually affect one side of the body. The main symptoms of Parkinson’s disease include:

• Tremors: uncontrollable shaking, the symptom most associated with the disease, often beginning in the hands.
• Rigidity: stiffness or tensing of the muscles.
• Bradykinesia: slowness of movement, and loss of spontaneous movement.

People with Parkinson’s disease may also experience other problems, including lack of balance and coordination, tiredness, depression, and difficulties with handwriting. They can also find their speech and facial expression change and some people have difficulties eating and swallowing.

What are the stages of Parkinson’s disease?

Parkinson’s disease is often divided into two parts; early stage and advanced stage disease.

• Early stage: when symptoms appear and start to affect everyday activities, such as washing, getting dressed and walking, enough so that treatment is needed.
• Advanced stage: when motor (movement) complications occur, due to use of one of the main treatments for Parkinson’s disease, levodopa.These complications usually happen when someone has been taking levodopa for some time.

How is Parkinson’s disease diagnosed?

There is no laboratory test for Parkinson’s disease, and diagnosis is made by reviewing medical history, a neurological exam and observation of symptoms.