What Causes Parkinson's Disease

“To date, despite decades of intensive study the causes of Parkinson’s remain unknown. Many experts think that the disease is caused by a combination of genetic and environmental factors, which may vary from person to person.” From the PD Foundation web site.

The Environment

Why me Lord? What have I done to so offend you? Was it the drugs when I was young? So I tried a few. What’s the big deal? They are even making some of them legal now and prescribing it medically. Do we pay later in life for the excesses of youth? No fair. We were young and free and happy to be alive at a great time. I know I’m not “perfect and upright” like Job but I can understand why he was just a wee bit upset. How have I so offended you as to deserve PD? “Teach me, and I will hold my tongue: and cause me to understand.”

Environmental causes means all causes that are not genetic. Age, the older you are the more your chances of getting PD. 1% of the population over 60, 0.001% under 45. It is not known why but men have a 50% higher risk to develop Parkinson’s than women. People who suffered traumatic head injuries, those exposed to toxic chemicals especially pesticides, and certain metals (manganese) and solvents have a higher incidence but there is no conclusive evidence that exposure to any single environmental factor acting alone can cause PD.

Genetics

Is it genetic? Did I inherit PD from my parents? They would be horrified. They were decent people and good parents. It’s the last thing they would have wanted. Am I going to pass this on to my children? I know you can’t argue with God but let me complain a little. Isn't there any wiggle room with heredity? Holy double helix, what is natural selection thinking? It’s bad enough that I have PD. No parent wants to pass disease on to their children. “Therefore I will not refrain my mouth. I will speak in the anguish of my spirit. I will complain in the bitterness of my soul.”

There are causal genes and associated genes. Causal genes occur in 1 - 2% of PD cases and guarantee that a person who lives long enough will develop PD without the influence of other genes or environmental factors. Associated genes increase the risk but do not develop PD on their own. A person with associated genes may never develop PD but is more likely to. They need to be combined with other genes or affected by the environment. Those with causal genes get PD if they live long enough, those with associated genes may or may not get it, and those with neither type gene may get PD due to environmental causes. 4 - 9% (the numbers vary) of those that have a parent or sibling with PD get it.  15 - 25% who have any relative with the disease get it.

It is more complicated than just environmental or genetic factors. Most researchers believe it is their interaction. That is, a person’s genetic makeup will determine the effect of an environmental exposure. Genetics make you a candidate for PD and environmental exposures can trigger it. In order to develop treatments to stop or reverse the disease scientists are working to identify the combinations of genes and environmental exposures that result in PD and researchers are looking for the genetic trigger that starts the cell death process in dopamine neurons.

Are there ways to prevent PD? There is no proven way to prevent PD. Some studies show that people who eat more fruits and veggies, high-fiber foods, fish, and omega-3 rich oils (the Mediterranean Diet) and who eat less red meat and dairy have a lower incidence of the disease. Reduced risk of developing the disease is also associated with smoking (yes smoking), caffeine, high vitamin D levels, exercise (everyone’s favorite), and greater physical activity. As of now though, “Man that is born of a woman is of few days and full of trouble.” Svet gornisht helfen, there is no help for it.