Understanding Parkinson’s Disease (Part 1)
Parkinson’s disease (PD) is a condition that involves the breakdown of nerve cells in the substantia nigra, the mid-brain part. These nerve cells produce dopamine, a chemical neurotransmitter that sends messages to that part of the brain controlling movement and coordination. When a person has PD, he doesn’t produce enough dopamine, so that he experiences tremors, slow movements, rigidity and difficulties with balance.
PD is not totally understood but it has something to do with the buildup of Lewy bodies in the mid-brain. This may explain the appearance of non-motor symptoms of PD even before any motor symptoms. Dopamine is also present in the intestines and degenerates with the progression of PD. That is why patients experience gastrointestinal symptoms like constipation.
Parkinson’s disease progresses over time. The earliest symptoms may be a slight tremor or shaking of the hands or fingers. Some patients experience stiffness like when the arms do not swing when walking. Others experience slowing of movements like taking smaller steps or dragging the feet when walking. There are still others who develop speech problems like slurring or hesitating when talking. As PD worsens, the patient may experience cognitive problems, such as dementia and depression.
Causes of PD
The exact cause of PD is not clear but experts believe that the two main causes of PD are genetics and the environment.
If a person has a first-degree relative like a parent or sibling who suffered from PD, the chances of having the condition is 4 to 9 percent higher than the general population. The genes that are connected to having PD may be:
Causal genes or the genes that cause the disease (alpha-synuclein). Even without other environmental factors, a person who has causal genes will surely develop PD. This type of genetic PD is not common as only 1-2% of patients with PD has this.
Associated genes or genes LRRK2 don’t cause PD per se but increase a person’s risk for having PD. When LRRK2 gene mutations occur, people can develop PD in their 30’s or 40’s; others have it in their 80’s; still others don’t develop PD at all. The type of effects experienced with LRRK2 gene mutations differ as well. Some have dementia while others have Lou Gehrig’s disease instead.
In Europe and North America, PD seems to be associated with living in the rural area, particularly in areas where people are into vegetable farming, drinking well water, or working in steel, wood pulp or paper industries.
In China, PD seems to be associated with industrialized urban areas. It has been found to be connected to long-term exposure to chemicals like pesticides, fungicides, herbicides and PCBs or heavy metals like lead, copper and manganese.
Sad to say, PD doesn’t have a cure. However, certain medications and activities can help manage the symptoms. So, if you’re seeing the symptoms on somebody including yourself, be sure to consult a doctor. He can help diagnose your condition and give the proper advice on what you should do.
Photo credit: Matthew Anderson via Flickr, CC BY-SA 2.0