What is Parkinson's Disease?
Parkinson’s disease is a chronic, slowly progressing brain condition described by medics as a “motor system disorder”. It affects the way the brain co-ordinates the body’s muscle movements and is one of the most common neurological disorders among elderly people.
It’s a disease which has been around for centuries and historians have found evidence of its existence as far back as 5,000 BC.
In 1817 London physician James Parkinson described it as the “shaking palsy”. He noted that the disease involved “involuntary tremulous motion, with lessened muscular power.” The disease later came to bear his name because of his pioneering work on identifying the symptoms and bringing the condition to the attention of the medical profession.
What is Parkinson’s – In a league of its own
It’s important to separate Parkinson’s disease from other conditions which produce similar symptoms. Doctors call Parkinson’s an idiopathic disease because no-one knows what causes it (the word idiopathic means “cause unknown”).
The term “parkinsonism” refers to a group of movement disorders, including idiopathic Parkinson’s, which produce the same signs and symptoms. In cases other than idiopathic Parkinson’s the causes - such as a stroke or the effects of continuous drug taking – can be identified.
Parkinson’s disease results from a lack of dopamine in the brain. The main area affected is a small section of the brain called the “substantia nigra” which transmits messages via neurotransmitters between the brain and nerve cells before passing them onto the muscles. Dopamine is one of these neurotransmitters.
For reasons that still baffle researchers, the nerve cells in the substantia nigra become damaged and degenerate and this in turn reduces the amount of dopamine available to the body. If there isn’t enough dopamine the nerve cells can’t function properly and messages don’t get through to the muscles. The lines of communication become progressively weaker until the brain can no longer control muscle movement effectively.
One or both sides of the body can be affected.
Studies have shown that 80% of dopamine producing cells have been damaged before the appearance of major symptoms such as muscle tremors, slowness of movement, balance problems and stiffness.
But scientists still don’t know what causes the problem - some believe it’s something in the environment, others say it’s genetic and some point to a combination of both. Genetics have been found to be an important factor in the onset of Parkinson’s in younger people. What researchers do know is that it mainly affects those over the age of 50 and becomes more common the older people get. It is estimated that two in 1,000 people over 50 are affected.
The disease is also known to be indiscriminate, although slightly more men than women fall victim to it.
It’s not a fatal condition but the mainstream medical profession tells us that, as yet, it is neither preventable nor curable. However, advances in modern medicine have made the disease very manageable.
High profile sufferers such as the actor Michael J Fox, who was diagnosed in his 30s, the boxer Muhammad Ali and Pope John Paul II, have increased public awareness of the illness. This has led to more money being ploughed into the kind of research which may one day provide the key to preventing and curing the disease.