Understanding Parkinson’s Disease: Causes, Symptoms, and Management

Parkinson’s is a disease associated with symptoms such as slow movement, muscle stiffness, muscle tremors and postural instability. The most common form is called Parkinson’s disease. Parkinson’s disease usually takes a gradual course and is still not curable. However, with the right therapy – usually in the form of medication – the progression of the disease can be stopped, and the life expectancy of the affected patients can be significantly increased. We will inform you about the causes and symptoms of Parkinson’s and the diagnosis and treatment of it.

Parkinson’s: cause unknown

Parkinson’s is one of the most widespread neurological diseases in Germany. It primarily affects older people between the ages of 55 and 65, and only around ten per cent are younger than 40 when they are diagnosed. The number of people who have Parkinson’s increases with age: in Germany, around one per cent of people over 60 are affected, around two per cent of people over 70 and three per cent of people over 80.

Parkinson’s disease is characterized by the progressive loss of nerve cells in the brain that produce dopamine as the disease progresses. It is not yet known why the nerve cells die. This is why it is also called idiopathic Parkinson’s syndrome (idiopathic = without a recognizable cause).

Different forms of Parkinson’s

Idiopathic Parkinson’s disease is by far the most common form – there is no identifiable cause for around 75 per cent of all Parkinson’s diseases. However, there are also some rarer forms of Parkinson’s disease whose causes are known:

• Familial Parkinson’s syndrome: This form of Parkinson’s is caused by changes in the genetic material and is, therefore, also hereditary. Symptoms often appear at a young age, i.e. under 40.
• Secondary (symptomatic) Parkinson’s syndrome: This form of Parkinson’s can be caused by environmental influences (e.g. toxins), certain medications (e.g. neuroleptics) or diseases (e.g. brain tumours), as well as repeated injuries to the brain (Boxer’s Parkinson’s).
• Atypical Parkinson’s syndrome includes various diseases that, like Parkinson’s, are caused by a deterioration of nerve cells in a specific area of ​​the brain – the basal ganglia. In addition to the typical Parkinson’s symptoms, those affected suffer from other complaints. That is why the atypical Parkinson’s syndrome is also known as Parkinson’s plus syndrome.

The key role of dopamine in Parkinson’s disease

Dopamine is a messenger substance that is primarily important for signal transmission between nerve cells in the brain and is, therefore, also involved in controlling our movements. If there is too little dopamine in the brain, the deficiency leads to the physical limitations typical of Parkinson’s disease, such as slowing down movement (bradykinesia).

Due to the lack of dopamine, other messenger substances, such as acetylcholine and glutamate, also gain the upper hand in the brain. The imbalance triggers typical signs, such as muscle shaking (tremor) and muscle stiffness (rigour).

Loss of dopamine-producing nerve cells

Dopamine deficiency is caused by a loss of dopamine-producing nerve cells in the brain. The loss is more pronounced in certain areas of the brain than in other regions: the dopamine-producing nerve cells in the black substance (substantia nigra) and the nerve cells in the striped body (striatum) are particularly affected.

Both the black substance and the striped body are involved in the control of movement processes. If there is too little dopamine, the nerve cells in these areas cannot be sufficiently stimulated. As a result, the movement sequences become slower and fine motor movements such as writing become more complex.