Parkinson’s disease and Parkinsonism

Parkinson’s disease results from degeneration of cells in a part of the brain called the basal ganglia, which controls the smoothness of muscle movements. Normally, these cells produce a neurotransmitter (a chemical that transmits nerve impulses) called dopamine, which acts with acetylcholine, an other neuro-transmitter, to fine-tune muscle control. In Parkinson’s disease, the level of dopamine relative to acetylcholine is reduced, adversely affecting muscle control.

About 1 in 200 people in the UJ has Parkinson’s disease. The disorder tends to occur after the age of 60 and is more common in men.

Parkinsonism is the term used for symptoms of Parkinson’s disease when they are due to an underlying disorder or certain drugs. Repeated head injuries may cause Parkinsonism, as may some antipsychotic drugs used to treat severe psychiatric illness.


What are the symptoms?

The main symptoms of Parkinson’s disease develop gradually over months or even years. Parkinsonism may have a gradual or sudden onset depending on the cause. Symptoms include:

- Tremor of on hand, arm or leg, usually when resting, that later occurs on both sides.
- Muscle stiffness, making it difficult to start moving.
- Slowness of movement.
- Shuffling walk with loss of arm swing.
- Expressionless or mask-like face.
- Stooped posture.

As the disease progresses, stiffness, immobility, and constant trembling of the hands may make some daily tasks difficult to perform. Speech may become slow and hesitant, and swallowing may be difficult. Many people with the disorder develop depression. About 3 in 10 people with the disease eventually develop dementia.

How is it diagnosed?

Since Parkinson’s disease begins gradually, it is often not possible to diagnose the condition immediately. Your doctor will examine you and may arrange tests such as CT scanning or MRI to exclude other possible causes. If a specific underlying disorder is found to be causing your symptoms, you will be diagnosed as having Parkinsonism rather than Parkinson’s disease.

How might the doctor treat it?

There is no specific cure for Parkinson’s disease, but drugs physical treatments, and more rarely, surgery can relieve symptoms. If you have Parkinsonism due to medications, your doctor may change your drugs. Symptoms the usually disappear within 8 weeks. If the symptoms persist, you may need to be treated with anti-parkinsonism drugs.

Drug treatment: in the early stages of Parkinson’s disease when symptoms are mild, treatment may not be necessary because drugs can not change the progression of the disease. Later on, drugs are used to relieve symptoms and reduce disability by correcting chemical imbalances in the brain, either by boosting dopamine levels or by blocking some the effects of acetylcholine or a combination of both. The choice and dosage of drugs is tailored to individual’s particular problems and adjusted to reduce side effects.

Often, an anti-cholinergic drug such as trihexyphenidyl (benzhexol) is given initially to reduce shaking and stiffness. Anti-cholinergic drugs can be effective for several years, but they may cause dry mouth, burred vision and difficulty in passing urine.

The main treatment for Parkinson’s disease is with levodopa, which boosts the level of dopamine within the brain. Levodopa controls major symptoms such as mobility problems but may initially cause side effects, such as nausea and vomiting. For this reason, the drug is increased gradually and is usually prescribed with other drugs, such as carbidopa or benserazide, which reduce the amount of levodopa that is needed. However, some people develop involuntary jerky or writhing movements as a side effect of this treatment. Levodopa is usually effective for 2-5 years, but long-term use may be associated with abrupt changes in symptoms known as the “one-off” effect of levodopa. The affected person has periods of normal mobility punctuated by unpredictable episodes of weakness and difficulty in moving.

When levodopa is no longer effective, seligiline, a drugs that slightly increases dopamine activity in the brain, may be tried, and later, other drugs, including dopamine agonists such s bromocriptine, may be used. Such drugs may cause confusion, hallucinations, and occasionally, aggressive behaviour. Although there is no wholly successful therapy for symptoms of this disease, new drugs are always being developed.

Physical treatment: the doctor may arrange for physiotherapy to help with mobility problems or speech therapy for speech and swallowing problems. If you are finding it difficult to cope at home, an occupational therapist may suggest changes, such as installing hand-rails to make it easier for you to move around.

Surgical treatment: younger people who are otherwise in good health may have surgery if the tremor cannot be controlled by drugs. Surgery involves destroying a part of the brain tissue responsible for the tremor. Therapies still being assessed include replacement of damaged brain cells with transplanted tissue and deep brain stimulation with electrical impulses to reduce tremor. Deep brain stimulation, in particular, holds promise as a future treatment.

What can I do?

It is important to pay attention to your general health. Taking a walk each day and doing simple stretching exercises will help you to maintain strength and mobility. You should also rest during they day to avoid getting tired. Emotional and practical help from family, friends, and support groups is important.

What is the prognosis?

The course of the Parkinson’s disease is variable, but drugs can be effective in treating the symptoms and improving the quality of life. People can lead active lives for many years after being diagnosed. However, most people with the disorder need daily help eventually, and their symptoms may be increasingly hard to control with drugs.