Parkinson's disease

What is Parkinson’s disease?#

Parkinson’s disease is a progressive, degenerative neurological condition that affects a person’s control of their body movements. It is not contagious, and a person cannot die from Parkinson’s symptoms themselves. In a very small percentage of cases the disease is thought to be genetic.

Symptoms are caused by the progressive degeneration of nerve cells in the middle of the brain, and in other organs such as the gut, that produce dopamine. Dopamine is a chemical messenger (neurotransmitter) necessary for smooth, controlled movement. Symptoms usually appear once about 70% of the dopamine-producing cells have stopped working normally.

Parkinson’s disease cannot be cured, but the symptoms can be managed with a combination of medication, multidisciplinary support from a team of allied health professionals, and deep brain stimulation surgery for some people. Many people with Parkinson’s live independent and productive lives.

How common is it?#

It is estimated that around four people per 1,000 have Parkinson’s disease, rising to about one in 100 in people over the age of 60. Around one in five people with Parkinson’s are diagnosed before the age of 50.

Symptoms#

The type, number, severity and progression of symptoms vary greatly. Every person is affected differently and may not get every symptom. Some of the more common symptoms include:

• resting tremor (shaking in a body part when it is at rest)
• rigidity (muscle stiffness)
• bradykinesia (slowness of movement)
• freezing (a sudden inability to move)
• difficulty with multitasking
• loss of volume in speech, stooped posture, shuffling gait, and small handwriting (micrographia)
• apathy, fatigue, sleep disturbance and loss of sense of smell
• depression, blood pressure fluctuation and constipation

People living with Parkinson’s for some time may also experience hallucinations (seeing, feeling or smelling something that is not present), paranoia (feeling that someone wants to harm you) or delusions (becoming convinced of something that is not true). These symptoms can be treated, so talk with your doctor.

What causes Parkinson’s disease?#

At present the cause of Parkinson’s disease is not known, and in most people there is no family history. Researchers worldwide are investigating possible causes, including:

• environmental triggers such as pesticides, toxins and chemicals
• genetic factors
• combinations of environmental and genetic factors
• head trauma

Diagnosis#

There are no specific diagnostic tests for Parkinson’s. X-rays, scans and blood tests may be used to rule out other conditions, so reaching a diagnosis can take some time. No two people with Parkinson’s have exactly the same symptoms or treatment, and your doctor or neurologist can help you decide which treatments to use.

Medication#

Medication therapy focuses on maximising the availability of dopamine in the brain, and regimes are individually tailored to your needs. Parkinson’s medications fall into broad categories, including:

• levodopa – dopamine replacement therapy
• dopamine agonists – mimic the action of dopamine
• COMT inhibitors – used with levodopa; they block the COMT enzyme so that less levodopa breaks down in the intestine, allowing more to reach the brain
• anticholinergics – block the effect of the neurotransmitter acetylcholine to rebalance its levels with dopamine
• MAO type B inhibitors – prevent the breakdown of dopamine within the brain
• amantadine – has anticholinergic properties and improves dopamine transmission

There is no single “best” treatment. Each person has different symptoms, disease progression, lifestyle and physical tolerances, and these affect the timing, type, dose and combination of medication. As the disease progresses, your doctor will review and adjust your program.

It is important to see a neurologist or doctor experienced in Parkinson’s disease, who can manage your doses and make adjustments, since side effects can be a problem at large doses. Take your medication promptly at the recommended time every day, wherever you are, as taking it late can severely hamper movement. Medication helps relieve symptoms but does not alter their progression over time, and it may become less effective, so your neurologist may try different options to get the most benefit.

Surgery#

Surgery is an option for treating Parkinson’s symptoms, but it is not suitable for everyone. There are strict criteria for who can be a candidate, and the decision is one only you and your doctor can make. Surgery may be considered early or late in the progression of the disease.

In deep brain stimulation surgery, the surgeon places an electrode in the part of the brain most affected by Parkinson’s. Electrical impulses are delivered through a pacemaker-like device called a stimulator, which helps “normalise” the brain’s electrical activity and reduce symptoms. Thalamotomy and pallidotomy, operations in which the surgeon makes an incision in part of the brain to ease some forms of tremor or unusual movement, are rarely performed now.

Support and a multidisciplinary team#

Early access to a multidisciplinary support team is important. These teams may include doctors, physiotherapists, occupational therapists, speech therapists, dietitians, social workers and specialist nurses. They assess the person with Parkinson’s and identify potential difficulties and possible solutions. Specialist teams may be limited in number, but generalist teams are becoming more aware of how to help.

Exercise#

Evidence suggests that regular exercise can improve some symptoms of Parkinson’s disease and improve quality of life. Consult closely with your doctor or healthcare professional when devising an exercise program. Benefits can include:

• better control over gross motor movements such as walking
• greater muscle strength and flexibility
• increased cardiovascular fitness
• improved coordination, balance and posture
• reduced risk of falling
• greater confidence in daily activities and reduced stress

Help for carers#

Being a carer for a person with Parkinson’s disease can be difficult. A range of agencies can provide help and support, including counselling, carer education programs, information and support groups.

Key points#

• It is not contagious or fatal – a person cannot die from Parkinson’s symptoms themselves.
• Symptoms are caused by the progressive degeneration of nerve cells in the middle of the brain.
• This causes a lack of dopamine, a neurotransmitter necessary for smooth, controlled movement.
• Symptoms appear when about 70% of the dopamine-producing cells have stopped working normally.
• Parkinson’s disease cannot be cured, but the symptoms can be managed.

Where to get help#