Parkinson’s disease

For unclear reasons, there is a reduction in nerve cells in a part of the brain called the substantia nigra. This part of the brain is involved in sending messages about movement to the rest of the body, and helps to produce the chemical dopamine which is a type of neurotransmitter, vital in helping the brain work normally. This then leads to a significant reduction in dopamine, an important chemical which, when levels are low, causes body movements to be uncoordinated and slowed.

The three main symptoms of Parkinson's disease are tremors, stiffness, and slowed movement. 

The symptoms start slowly, usually with a tremor affecting one hand, and progressively worsen, although not everyone develops a tremor. The tremor (shaking) is usually worse at rest or if you are stressed, the stiffness can affect any muscle but often causes your arms to swing less when walking, and the slowed movement can lead to a shuffling type of walk over time.

Other symptoms include a change in posture, making you more prone to falls, and there may be a lack of facial expressions, such as smiling or frowning, with reduced blinking and softer, more slurred speech. Handwriting may become very small or ‘spidery’ and there may also be problems sleeping, nightmares, constipation, worsening memory, depression, and anxiety. In some people, impulsive behavior can develop, such as gambling or compulsive shopping.

It is also now known – for reasons that are not yet clear – that people with PD are more prone to developing skin cancer, so skin protection is essential.

There is no test that can diagnose Parkinson's disease. Your doctor will talk to you about your symptoms and how it affects your daily activity. They will ask you to complete a memory test to understand the severity of your symptoms and assess how you walk. If there is doubt about the diagnosis a brain scan may be done to see if other conditions are present.

In the early stages, Parkinson's can be quite difficult to diagnose. If your doctor thinks you may have Parkinson's, they will refer you to a specialist who will ask you to perform more detailed exercises and activities. At times, to confirm whether you have Parkinson's, your doctor may try you on a medication - to see if your symptoms respond well.

There is no cure for Parkinson's, but treatment can be very effective in reducing the progression of the disease and improving life expectancy.

If the symptoms are mild, not much may be needed in terms of treatment. More severe symptoms may require occupational therapists, who can ensure your home is safe and modifications are made, and physiotherapists - to support your posture, balance, and movement.

The medication levodopa can be tried in combination with other medications, and almost all people will see a benefit from this initially, although its effects gradually reduce and so the dose usually needs to be increased over time.

Other possible treatments include dopamine agonists, monoamine-oxidase-B inhibitors (MAOBs) such as selegiline and rasagiline that block some chemicals in the brain that break down dopamine (and so help make its effects last longer), and COMT inhibitors that also help to stop dopamine from being broken down by the body.

In rare cases, brain surgery may be undertaken if medicines do not work well. One method involves chronic deep brain stimulation which uses electrodes to stimulate the part of the brain affected by PD.

Your specialist doctor will also monitor you regularly and alter treatments as and when required.

The Parkinsons Foundation is a great resource for further information.