Parkinson's Disease Support Group
Parkinson's disease is a movement disorder often characterized by muscle rigidity, tremor, a slowing of physical movement, and in extreme cases, a loss of physical movement. The primary symptoms of Parkinsons are due to excessive muscle contraction, normally caused by the insufficient formation and action of dopamine, which is produced in the dopaminergic neurons of the...
I've looked on the web, but couldn't find a definitive estimate or discussion on this. So thought I'd post here to see if anyone knows anything or is aware of studies.
As I've read on MJF site and other places, by the time you start seeing symptoms, around 80% of dopamine neurons have ceased functioning.
Give the rate of neuron loss after diagnosis, it would seem logical that the rate of neuron loss started some years prior to experiencing symptoms. The one article I did find that appeared to relate studied rate progression after PD diagnosis:
http://www.pdf.org/en/science_news/release/pr_1379423617
Which seemed to support the idea that PD loss rates would start years before symptoms are noticed. One application of that information is the ability to detect PD early, before symptoms are noticed.
I'm interested in this in part because my wife is concerned that some stress she put me through about a year before my symptoms started appearing caused me to get PD. So she's feeling guilty even though I've told her there is nothing definitive that says emotional trauma causes PD. But since there is nothing that says it doesn't, she's not convinced.
But if the above is true, even if emotional trauma can cause PD, one year wouldn't likely be enough time to lose enough neuron activity for symptoms to show up. Which would mean I had PD long before the trauma happened. At worst, the trauma might have accelerated the time frame.
But then, it is possible such things could trigger a rate-loss spike too, though I've read nothing to suggest such.
Update:
"While emotional or a psychological trauma can precipitate the initial symptoms or aggravate existing symptoms, this is not the actual cause of the disorder."
http://www.doctorslounge.com/neurology/diseases/parkinson.htm
As I've read on MJF site and other places, by the time you start seeing symptoms, around 80% of dopamine neurons have ceased functioning.
Give the rate of neuron loss after diagnosis, it would seem logical that the rate of neuron loss started some years prior to experiencing symptoms. The one article I did find that appeared to relate studied rate progression after PD diagnosis:
http://www.pdf.org/en/science_news/release/pr_1379423617
Which seemed to support the idea that PD loss rates would start years before symptoms are noticed. One application of that information is the ability to detect PD early, before symptoms are noticed.
I'm interested in this in part because my wife is concerned that some stress she put me through about a year before my symptoms started appearing caused me to get PD. So she's feeling guilty even though I've told her there is nothing definitive that says emotional trauma causes PD. But since there is nothing that says it doesn't, she's not convinced.
But if the above is true, even if emotional trauma can cause PD, one year wouldn't likely be enough time to lose enough neuron activity for symptoms to show up. Which would mean I had PD long before the trauma happened. At worst, the trauma might have accelerated the time frame.
But then, it is possible such things could trigger a rate-loss spike too, though I've read nothing to suggest such.
Update:
"While emotional or a psychological trauma can precipitate the initial symptoms or aggravate existing symptoms, this is not the actual cause of the disorder."
http://www.doctorslounge.com/neurology/diseases/parkinson.htm
I was under HUGE stress when my symptoms appeared (not good stress), and I know I was also in that situation when I have had my bouts with cancer, and strokes. Learning to manage stress is ongoing -- but like you, while it may be a precipapator, I don't think its a "cause". Prayers for your wife's peace of mind.
Terrapin: Interesting study and numbers. At what point in life does it suggest the attrition begins? Birth, or some time in teen years? Assuming an average of 10% (which would change to a higher rate each decade assuming same rate of loss), first decade that would amount to a loss of 45,000. Assuming the 20s are the first decade of loss, by age 70 under normal aging loss a person would be around 50% loss of neurons. At the age I was at, 51, around 30% loss. Which means PD would have added around an additional 50% of loss to get me to 80% to start noticing tremors.
Point being, obviously, this is a slow process that started some years before symptoms showed up.
Annie: Yes, stress is well documented in increasing PD symptoms. One article I read (I don't know how accurate it is) said dopamine relaxes muscles, while another chemical contracts them. The dopamine levels get higher or lower than the other neurotransmitter in order to control muscle movement. Low dopamine levels keep the other more substantially higher regularly, creating constant muscle contractions (distonia) and the difficulty in controlling muscle movement (tremors, bradykinesia).
Stress kicks in adrenaline, which temporarily lowers dopamine levels. For a normal person, they probably won't experience any of that as they have enough buffer of dopamine. In PD, however, we're often already in the negative, so further lowering of dopamine increases the symptoms more.
But like you say, that only addresses why stress worsens PD symptoms, but has no bearing on causing PD in the first place.
Thanks all, for the info.
You guys are SO great in your "shares", caring, and researched information. I appreciate you all beyond words.
(1) A Jan. 2014 article states, "...The main challenge for the medical profession lies in diagnosing the disease at an early stage, since it first takes root in the body 20 to 30 years before the first symptoms manifest themselves, which usually happens only at the later stages." (Source: http://www.nwpf.org/stay-informed/news/2014/01/russian-doctors-develop-new-tests-for-parkinsons/ )
(2) 10 years earlier, in 2004, there was this: "...The loss of brain cells that leads to Parkinson''s disease starts an estimated 13 years before the diagnosis, according to research that will be presented at the American Academy of Neurology 56th Annual Meeting in San Francisco, Calif., April 24 May 1, 2004." (Source: https://www.aan.com/PressRoom/Home/PressRelease/197 )
(3) Here's a 2010 article connecting REM sleep disorder with PD and as many as 50 years before presentation of initial symptoms:
http://io9.com/5599244/a-sleep-disorder-can-reveal-you-have-parkinsons---50-years-before-you-develop-the-disease
(4) This final link is for a very informative, 15-page article that, in my opinion, is well worth the time it takes to read it. Some info. has been challenged by recent clinical trials, e.g., the effectiveness of CoQ10, which doesn't appear to help ease symptoms once one has PD. That being said, there's LOTS of other excellent info. in this article, though. Among many other things, it mentions a study in which constipation "documented in medical records as much as 20-years before disease onset was associated with a significantly increased risk..." Source: http://www.lef.org/protocols/neurological/parkinsons_disease_01.htm
I'm sure a Google search will turn up many other articles, but hopefully this sheds some light on the issue.
I told my wife tonight about the info you've all shared. She had convinced herself that she gave me PD. It took a bit for the reality to sink in, but I think she finally began to realize it can't be true. She's been living with this guilt ever since I started showing obvious symptoms toward the end of 2012, that it may take her a while to adjust her feelings to the fact she isn't guilty.